Particulates Explained

Particulates or atmospheric particulate matter (see below for other names) are microscopic particles of solid or liquid matter suspended in the air. The term aerosol commonly refers to the particulate/air mixture, as opposed to the particulate matter alone.^[1] Sources of particulate matter can be natural or anthropogenic.^[2] They have impacts on climate and precipitation that adversely affect human health, in ways additional to direct inhalation.

Types of atmospheric particles include suspended particulate matter; thoracic and respirable particles;^[3] inhalable coarse particles, designated PM, which are coarse particles with a diameter of 10 micrometers (μm) or less; fine particles, designated PM, with a diameter of 2.5 μm or less;^[4] ultrafine particles, with a diameter of 100 nm or less; and soot.

Airborne particulate matter is a Group 1 carcinogen.^[5] Particulates are the most harmful form (other than ultra-fines) of air pollution^[6] as they can penetrate deep into the lungs and brain from blood streams, causing health problems such as heart disease, lung disease, cancer and preterm birth.^[7] There is no safe level of particulates. Worldwide, exposure to PM contributed to 4.1 million deaths from heart disease, stroke, lung cancer, chronic lung disease, and respiratory infections in 2016.^[8] Overall, ambient particulate matter is one of the leading risk factor for premature death globally.^[9]

Sources

Human activities generate significant amounts of particulates. For example:

• Burning of fossil fuels (e.g., aircraft),^{[10] [11]} joss paper,^{[12] [13] [14]} waste,^[15] firecrackers^[16] and biomass including wood^[17] and crop residue.
• Construction (including activities of building rehabilitation/ refurbishment or demolition).^{[18] [19] [20] [21]}
• Renovation.^{[22] [23]}
• Roadworks, diesel exhausts of the heavy equipments used, emission from the production of building materials, etc.^{[24] [25] [26] [27]}
• Dusty materials that are not cleaned up or properly covered (e.g., in construction sites, landfills and ceramics production facilities; ashes left from burning or wildfires).^{[28] [29] [30]}
• Metalworking (e.g., welding).^[31]
• Woodworking.^{[32] [33]}
• Glass reprocessing.
• Industries.
• Cooking (frying, boiling, grilling).^[34]
• Agricultural activities (e.g., ploughing and soil tilling).^[35]
• Power plants.^[36]
• Waste incineration.^{[37] [38]}
• Road dust from tyre and road wear^[39] and road dust from unpaved road.^[40]
• Wet cooling towers in cooling systems.
• Various industrial processes such as mining,^{[41] [42]} smelting^[43] and oil refining.^[44]
• Disasters^[45] (both natural or caused by humans, e.g., wildfires, earthquakes, wars,^{[46] [47]} and September 11 attacks, etc.).
• Microplastics (gaining attention as a type of airborne PM).^{[48] [49]}

Human-made (anthropogenic) aerosols account for about 10 percent of the total mass of aerosols in the atmosphere as estimated in 2010. The remaining 90 percent comes from natural sources such as volcanoes, dust storms, forest and grassland fires, living vegetation and sea spray, emitting particulates such as volcanic ash, desert dust, soot and sea salt.^[50]

Domestic combustion and wood smoke

In the United Kingdom domestic combustion is the largest single source of PM and PM annually, with domestic wood burning in both closed stoves and open fires responsible for 38% of PM in 2019.^{[51] [52] [53]} To tackle the problem some new laws were introduced since 2021. In some towns and cities in New South Wales wood smoke may be responsible for 60% of fine particle air pollution in the winter.^[54]

There are a few ways to reduce wood smoke, e.g., buying the right wood heater and maintaining it well,^[55] choosing the right firewood^[56] and burning it the right way.^[57] There are also regulations in some countries where people can report smoke pollution to the local council.^[58]

Composition

The composition and toxicity of aerosols, including particles, depends on their source and atmospheric chemistry and varies widely.Wind-blown mineral dust^[59] tends to be made of mineral oxides and other material blown from the Earth's crust; this particulate is light-absorbing.^[60] Sea salt^[61] is considered the second-largest contributor in the global aerosol budget, and consists mainly of sodium chloride originated from sea spray; other constituents of atmospheric sea salt reflect the composition of sea water, and thus include magnesium, sulfate, calcium, potassium, and others. In addition, sea spray aerosols may contain organic compounds like fatty acids and sugars, which influence their chemistry.^[62]

Some secondary particles derive from the oxidation of primary gases such as sulfur and nitrogen oxides into sulfuric acid (liquid) and nitric acid (gaseous) or from biogenic emissions. The precursors for these aerosols—i.e. the gases from which they originate—may have an anthropogenic origin (from biomass and fossil fuel combustion) as well as a natural biogenic origin. In the presence of ammonia, secondary aerosols often take the form of ammonium salts; i.e. ammonium sulfate and ammonium nitrate (both can be dry or in aqueous solution); in the absence of ammonia, secondary compounds take an acidic form as sulfuric acid (liquid aerosol droplets) and nitric acid (atmospheric gas), all of which probably contribute to the health effects of particulates.^[63]

Secondary sulfate and nitrate aerosols are strong light-scatterers.^[64] This is mainly because the presence of sulfate and nitrate causes the aerosols to increase to a size that scatters light effectively.

Organic matter (OM) found in aerosols can be either primary or secondary, the latter part deriving from the oxidation of volatile organic compounds (VOCs); organic material in the atmosphere may either be biogenic or anthropogenic. Organic matter influences the atmospheric radiation field by both scattering and absorption. Some aerosols are predicted to include strongly light-absorbing material and are thought to yield large positive radiative forcing. Some secondary organic aerosols (SOAs) resulting from combustion products of internal combustion engines, have been identified as a danger to health.^[65] Particulate toxicity has been found to vary by region and source contribution which affects the particles chemical composition.

The chemical composition of the aerosol directly affects how it interacts with solar radiation. The chemical constituents within the aerosol change the overall refractive index. The refractive index will determine how much light is scattered and absorbed.

The composition of particulate matter that generally causes visual effects, haze, consists of sulfur dioxide, nitrogen oxides, carbon monoxide, mineral dust, and organic matter. The particles are hygroscopic due to the presence of sulfur, and SO is converted to sulfate when high humidity and low temperatures are present. This causes reduced visibility and red-orange-yellow colors.^[66]

Size distribution

Human-produced aerosols such as particle pollution tend to have a smaller radius than aerosol particles of natural origin (such as windblown dust). The false-color maps in the map of distribution of aerosol particles on the right show where there are natural aerosols, human pollution, or a mixture of both, monthly.

Smaller aerosols in the North

The size distribution time series shows that in the planet's most southerly latitudes, nearly all the aerosols are large, but in the high northern latitudes, smaller aerosols are very abundant. Most of the Southern Hemisphere is covered by the ocean, where the largest source of aerosols is natural sea salt from dried sea spray. Because the land is concentrated in the Northern Hemisphere, the amount of small aerosols from fires and human activities is greater there than in the Southern Hemisphere. Overland, patches of large-radius aerosols appear over deserts and arid regions, most prominently, the Sahara Desert in North Africa and the Arabian Peninsula, where dust storms are common. Places where human-triggered or natural fire activity is common (land-clearing fires in the Amazon from August–October, for example, or lightning-triggered fires in the forests of northern Canada in Northern Hemisphere summer) are dominated by smaller aerosols. Human-produced (fossil fuel) pollution is largely responsible for the areas of small aerosols over developed areas such as the eastern United States and Europe, especially in their summer.

Satellite measurements of aerosols, called aerosol optical thickness, are based on the fact that the particles change the way the atmosphere reflects and absorbs visible and infrared light. As shown in this page, an optical thickness of less than 0.1 (palest yellow) indicates a crystal clear sky with maximum visibility, whereas a value of 1 (reddish-brown) indicates very hazy conditions.

Deposition processes

See main article: Deposition (aerosol physics).

See also: Global distillation. In general, the smaller and lighter a particle is, the longer it will stay in the air. Larger particles (greater than 10 micrometers in diameter) tend to settle to the ground by gravity in a matter of hours. The smallest particles (less than 1 micrometer) can stay in the atmosphere for weeks and are mostly removed by precipitation. There are evidence that aerosols can "travel across the ocean". For example, in September 2017 wildfires burning across the western United States and Canada, and the smoke was found to have arrived over the United Kingdom and northern France in three days, as shown by satellite images.^[67] Diesel particulate matter is highest near the source of emission.^[68] Any information regarding DPM and the atmosphere, flora, height, and distance from major sources is useful to determine health effects.

Control

Technologies

See main article: Dust collector.

See also: Dust collection system. Particulate matter emissions are highly regulated in most industrialized countries. Due to environmental concerns, most industries are required to operate some kind of dust collection system.^[69] These systems include inertial collectors (cyclonic separators), fabric filter collectors (baghouses), electrostatic filters used in facemasks,^[70] wet scrubbers, and electrostatic precipitators.

Cyclonic separators are useful for removing large, coarse particles and are often employed as a first step or "pre-cleaner" to other more efficient collectors. Well-designed cyclonic separators can be very efficient in removing even fine particulates,^[71] and may be operated continuously without requiring frequent shutdowns for maintenance.

Fabric filters or baghouses are the most commonly employed in general industry.^[72] They work by forcing dust-laden air through a bag-shaped fabric filter leaving the particulate to collect on the outer surface of the bag and allowing the now clean air to pass through to either be exhausted into the atmosphere or in some cases recirculated into the facility. Common fabrics include polyester and fiberglass and common fabric coatings include PTFE (commonly known as Teflon). The excess dust buildup is then cleaned from the bags and removed from the collector.

Wet scrubbers pass the dirty air through a scrubbing solution (usually a mixture of water and other compounds) allowing the particulate to attach to the liquid molecules.^[73] Electrostatic precipitators electrically charge the dirty air as it passes through. The now charged air then passes through large electrostatic plates which attract the charged particle in the airstream collecting them and leaving the now clean air to be exhausted or recirculated.^[74]

Measures

For general building construction, some places that have acknowledged the possible health risks of construction dust for decades legally require the relevant contractor to adopt effective dust control measures, although inspections, fines and imprisonments are rare in recent years (for example, two prosecutions with a total fines of HKD$6000 in Hong Kong in the year 2021).^{[75] [76]}

Some of the mandatory dust control measures include^{[77] [78] [79]} load, unload, handle, transfer, store or dispose of cement or dry pulverized fuel ash in a completely enclosed system or facility, and fit any vent or exhaust with an effective fabric filter or equivalent air pollution control system or equipment, enclose the scaffolding of the building with dust screens, use impervious sheeting to enclose both material hoist and debris chute, wet debris with water before it is dumped into a debris chute, have water sprayed on the facade surface before and during grinding work, use grinder equipped with vacuum cleaner for facade grinding work, spray water continuously on the surface for any pneumatic or power-driven drilling, cutting, polishing or other mechanical breaking operation that causes dust emission, unless there is the operation of an effective dust extraction and filtering device, provide hoarding of not less than 2.4 m in height along the whole length of the site boundary, have hard paving on open area and wash every vehicle that leaves the construction sites. Use of automatic sprinkler equipment, automatic carwash equipment and installation of video surveillance system for the pollution control facilities and retain the videos for one month for future inspections.

Besides removing particulates from the source of pollution, they may also be cleaned in the open air (e.g. smog tower, moss wall, and water truck),^[80] while other control measures employ the use of barriers.^[81]

Measurement

See main article: Air pollution measurement.

Particulates have been measured in increasingly sophisticated ways since air pollution was first systematically studied in the early 20th century. The earliest methods included relatively crude Ringelmann charts, which were grey-shaded cards against which emissions from smokestacks could be visually compared, and deposit gauges, which collected the soot deposited in a particular location so it could be weighed. Automated, modern methods of measuring particulates include optical photodetectors, tapered element oscillating microbalances, and Aethalometers.^[82] Besides measuring the total mass of particles per unit volume of air (particle mass concentration), sometimes it is more useful to measure the total number of particles per unit volume of air (particle number concentration). This can be done by using a condensation particle counter (CPC).^{[83] [84]}

To measure the atomic composition of particulate samples, techniques such as X-ray spectrometry can be used.^[85]

Climate effects

Atmospheric aerosols affect the climate of the Earth by changing the amount of incoming solar radiation and outgoing terrestrial longwave radiation retained in the Earth's system. This occurs through several distinct mechanisms which are split into direct, indirect^{[86] [87]} and semi-direct aerosol effects. The aerosol climate effects are the biggest source of uncertainty in future climate predictions. The Intergovernmental Panel on Climate Change (IPCC) stated in 2001:^[88]

While the radiative forcing due to greenhouse gases may be determined to a reasonably high degree of accuracy... the uncertainties relating to aerosol radiative forcings remain large, and rely to a large extent on the estimates from global modeling studies that are difficult to verify at the present time.

Aerosol radiative

Direct

The direct aerosol effect consists of any direct interaction of radiation with atmospheric aerosols, such as absorption or scattering. It affects both short and longwave radiation to produce a net negative radiative forcing.^[89] The magnitude of the resultant radiative forcing due to the direct effect of an aerosol is dependent on the albedo of the underlying surface, as this affects the net amount of radiation absorbed or scattered to space. For example, if a highly scattering aerosol is above a surface of low albedo it has a greater radiative forcing than if it was above a surface of high albedo. The converse is true of absorbing aerosol, with the greatest radiative forcing arising from a highly absorbing aerosol over a surface of high albedo. The direct aerosol effect is a first-order effect and is therefore classified as a radiative forcing by the IPCC.^[90] The interaction of an aerosol with radiation is quantified by the single-scattering albedo (SSA), the ratio of scattering alone to scattering plus absorption (extinction) of radiation by a particle. The SSA tends to unity if scattering dominates, with relatively little absorption, and decreases as absorption increases, becoming zero for infinite absorption. For example, the sea-salt aerosol has an SSA of 1, as a sea-salt particle only scatters, whereas soot has an SSA of 0.23, showing that it is a major atmospheric aerosol absorber.

Indirect

The Indirect aerosol effect consists of any change to the Earth's radiative budget due to the modification of clouds by atmospheric aerosols and consists of several distinct effects. Cloud droplets form onto pre-existing aerosol particles, known as cloud condensation nuclei (CCN). Droplets condensing around human-produced aerosols such as found in particulate pollution tend to be smaller and more numerous than those forming around aerosol particles of natural origin (such as windblown dust).^[50]

For any given meteorological conditions, an increase in CCN leads to an increase in the number of cloud droplets. This leads to more scattering of shortwave radiation i.e. an increase in the albedo of the cloud, known as the cloud albedo effect, First indirect effect or Twomey effect. Evidence supporting the cloud albedo effect has been observed from the effects of ship exhaust plumes^[91] and biomass burning^[92] on cloud albedo compared to ambient clouds. The Cloud albedo aerosol effect is a first order effect and therefore classified as a radiative forcing by the IPCC.

An increase in cloud droplet number due to the introduction of aerosol acts to reduce the cloud droplet size, as the same amount of water is divided into more droplets. This has the effect of suppressing precipitation, increasing the cloud lifetime, known as the cloud lifetime aerosol effect, second indirect effect or Albrecht effect. This has been observed as the suppression of drizzle in ship exhaust plume compared to ambient clouds,^[93] and inhibited precipitation in biomass burning plumes.^[94] This cloud lifetime effect is classified as a climate feedback (rather than a radiative forcing) by the IPCC due to the interdependence between it and the hydrological cycle. However, it has previously been classified as a negative radiative forcing.^[95]

Semi-direct

The Semi-direct effect concerns any radiative effect caused by absorbing atmospheric aerosol such as soot, apart from direct scattering and absorption, which is classified as the direct effect. It encompasses many individual mechanisms, and in general is more poorly defined and understood than the direct and indirect aerosol effects. For instance, if absorbing aerosols are present in a layer aloft in the atmosphere, they can heat surrounding air which inhibits the condensation of water vapour, resulting in less cloud formation.^[96] Additionally, heating a layer of the atmosphere relative to the surface results in a more stable atmosphere due to the inhibition of atmospheric convection. This inhibits the convective uplift of moisture,^[97] which in turn reduces cloud formation. The heating of the atmosphere aloft also leads to a cooling of the surface, resulting in less evaporation of surface water. The effects described here all lead to a reduction in cloud cover i.e. an increase in planetary albedo. The semi-direct effect classified as a climate feedback) by the IPCC due to the interdependence between it and the hydrological cycle. However, it has previously been classified as a negative radiative forcing.^[95]

Specific aerosol roles

Sulfate

See also: Global dimming and Stratospheric aerosol injection. Sulfate aerosols are mostly inorganic sulfur compounds like (SO₄^2-),HSO₄^- and H₂SO₄^-,^[98] which are mainly produced when sulfur dioxide reacts with water vapor to form gaseous sulfuric acid and various salts (often through an oxidation reaction in the clouds), which are then thought to experience hygroscopic growth and coagulation and then shrink through evaporation.^[99] Some of them are biogenic (typically produced via atmospheric chemical reactions with dimethyl sulfide from mostly marine plankton^[100]) or geological via volcanoes or weather-driven from wildfires and other natural combustion events,^[101] but in the recent decades anthropogenic sulfate aerosols produced through combustion of fossil fuels with a high sulfur content, primarily coal and certain less-refined fuels, like aviation and bunker fuel, had dominated.^[102] By 1990, global human-caused emissions of sulfur into the atmosphere became "at least as large" as all natural emissions of sulfur-containing compounds combined, and were at least 10 times more numerous than the natural aerosols in the most polluted regions of Europe and North America,^[103] where they accounted for 25% or more of all air pollution. This led to acid rain,^{[104] [105]} and also contributed to heart and lung conditions ^[106] and even the risk of preterm birth and low birth weight.^[107] Sulfate pollution also has a complex relationship with NOx pollution and ozone, reducing the also harmful ground-level ozone, yet capable of damaging the stratospheric ozone layer as well.^[108] Once the problem became clear, the efforts to remove this pollution through flue-gas desulfurization measures and other pollution controls were largely successful,^[109] reducing their prevalence by 53% and causing healthcare savings valued at $50 billion annually in the United States alone.^{[110] [111]} Yet, around the same time, research had shown that sulfate aerosols were affecting both the visible light received by the Earth and its surface temperature,^[112] and as the so-called global dimming) began to reverse in the 1990s in line with the reduced anthropogenic sulfate pollution,^{[113] [114]} climate change accelerated.^[115] As of 2021, state-of-the-art CMIP6 models estimate that total cooling from the currently present aerosols is between 0.1C-change to 0.7C-change;^[116] the IPCC Sixth Assessment Report uses the best estimate of 0.5C-change,^[117] with the uncertainty mainly caused by contradictory research on the impacts of aerosols of clouds.^{[118] [119] [120] [121] [122] [123]} Some are certain that they cool the planet, though, and this led to solar geoengineering proposals known as stratospheric aerosol injection, which seeks to replicate and enhance the cooling from sulfate pollution while minimizing the negative effects on health through deploying in the stratosphere, where only a fraction of the current sulfur pollution would be needed to avoid multiple degrees of warming,^[124] but the assessment of costs and benefits remains incomplete,^[125] even with hundreds of studies into the subject completed by the early 2020s.^[126]

Black carbon

Black carbon (BC), or carbon black, or elemental carbon (EC), often called soot, is composed of pure carbon clusters, skeleton balls and fullerenes, and is one of the most important absorbing aerosol species in the atmosphere. It should be distinguished from organic carbon (OC): clustered or aggregated organic molecules on their own or permeating an EC buckyball. Black carbon from fossil fuels is estimated by the IPCC in the Fourth Assessment Report of the IPCC, 4AR, to contribute a global mean radiative forcing of +0.2 W/m² (was +0.1 W/m² in the Second Assessment Report of the IPCC, SAR), with a range +0.1 to +0.4 W/m². A study published in 2013 however, states that "the best estimate for the industrial-era (1750 to 2005) direct radiative forcing of atmospheric black carbon is +0.71 W/m² with 90% uncertainty bounds of (+0.08, +1.27) W/m²" with "total direct forcing by all-black carbon sources, without subtracting the preindustrial background, is estimated as +0.88 (+0.17, +1.48) W/m²".^[127]

Instances

See also: Haze. Volcanoes are a large natural source of aerosol and have been linked to changes in the Earth's climate often with consequences for the human population. Eruptions linked to changes in climate include the 1600 eruption of Huaynaputina which was linked to the Russian famine of 1601–1603,^{[128] [129] [130]} leading to the deaths of two million, and the 1991 eruption of Mount Pinatubo which caused a global cooling of approximately 0.5 °C lasting several years.^{[131] [132]} Research tracking the effect of light-scattering aerosols in the stratosphere during 2000 and 2010 and comparing its pattern to volcanic activity show a close correlation. Simulations of the effect of anthropogenic particles showed little influence at present levels.^{[133] [134]}

Aerosols are also thought to affect weather and climate on a regional scale. The failure of the Indian monsoon has been linked to the suppression of evaporation of water from the Indian Ocean due to the semi-direct effect of anthropogenic aerosol.^[135]

Recent studies of the Sahel drought^[136] and major increases since 1967 in rainfall in Australia over the Northern Territory, Kimberley, Pilbara and around the Nullarbor Plain have led some scientists to conclude that the aerosol haze over South and East Asia has been steadily shifting tropical rainfall in both hemispheres southward.^[137]

Health effects

See also: Health effects of wood dust and Health and environmental impact of the coal industry.

Size, shape, and solubility matter

Size

Particle size is the main determinant of where in the respiratory tract it will come to rest when inhaled. Larger particles are generally filtered in the nose and throat via cilia and mucus, but particulate matter smaller than about 10 micrometers can settle in the bronchi and lungs and cause health problems. The 10-micrometer size does not represent a strict boundary between respirable and non-respirable particles but has been agreed upon for monitoring of airborne PM by most regulatory agencies. Because of their small size, particles on the order of 10 micrometers or less (coarse particulate matter, PM) can penetrate the deepest part of the lungs such as the bronchioles or alveoli.^[138] When asthmatics are exposed to these conditions it can trigger bronchoconstriction.^[139]

Similarly, fine particulate matter (PM) tends to penetrate into the gas exchange regions of the lung (alveoli), and very small particles (ultrafine particulate matter PM) may pass through the lungs to affect other organs. Penetration of particles is not wholly dependent on their size; shape and chemical composition also play a part. To avoid this complication, simple nomenclature is used to indicate the different degrees of relative penetration of a PM particle into the cardiovascular system. Inhalable particles penetrate no further than the bronchi as they are filtered out by the cilia. Thoracic particles can penetrate right into terminal bronchioles.

In analogy, the inhalable dust fraction is the fraction of dust entering the nose and mouth which may be deposited anywhere in the respiratory tract. The thoracic fraction is the fraction that enters the thorax and is deposited within the lung's airways. The respirable fraction is what is deposited in the gas exchange regions (alveoli).^[140]

The smallest particles, nanoparticles, which are less than 180 nanometers in size, may be even more damaging to the cardiovascular system.^{[141] [142]} Nanoparticles can pass through cell membranes and migrate into other organs, including the brain. Particles emitted from modern diesel engines (commonly referred to as Diesel Particulate Matter, or DPM) are typically in the size range of 100 nanometers (0.1 micrometers). These soot particles also carry carcinogens like benzopyrenes adsorbed on their surface.

Particulate mass is not a proper measure of the health hazard. A particle of 10 μm diameter has approximately the same mass as 1 million particles of 100 nm diameter, but is much less hazardous, as it is unlikely to enter the alveoli. Legislative limits for engine emissions based on mass are therefore not protective. Proposals for new regulations exist in some countries, with suggestions to limit the particle surface area or the particle count (numerical quantity) / particle number concentration (PNC) instead.^{[143] [144]}

Solubility

The site and extent of absorption of inhaled gases and vapors are determined by their solubility in water. Absorption is also dependent upon air flow rates and the partial pressure of the gases in the inspired air. The fate of a specific contaminant is dependent upon the form in which it exists (aerosol or particulate). Inhalation also depends upon the breathing rate of the subject.^[145]

Shape

Another complexity not entirely documented is how the shape of PM can affect health, except for the needle-like shape of asbestos fibres which can lodge in the lungs. Geometrically angular shapes have more surface area than rounder shapes, which in turn affects the binding capacity of the particle to other, possibly more dangerous substances. The table below lists the colours and shapes of some common atmospheric particulates:^[146]

Type of particulate	Color	Shape
Portland cement	Gray	Irregular
Smolder smoke	White	Spherical
Soot	Black	Fractal aggregate
Water droplets	White	Spherical
Loess	Yellow Brown	Irregular
Lokon volcanic ash	Dark Brown	Irregular
Sahara sand (Libya)	Brown	Irregular

Composition, quantity, and duration are important

Composition of particles can vary greatly depending on their sources and how they are produced. For example, dust emitted from the burning of living and dead vegetation would be different from those emitted from the burning of joss paper or construction wastes. Particles emitted from fuel combustion are not the same as those emitted from waste combustion. The particulate matter generated from the fire of a recycling yard^[147] or a ship full of scrap metal^{[148] [149]} may contain more toxic substances than other types of burning.

Different types of building refurbishment activities produce different kinds of dust too. The composition of PM generated from cutting or mixing concrete made with Portland Cement would be different from those generated from cutting or mixing concrete made with different types of slag (e.g. GGBFS, EAF slag^[150]), fly ash or even EAF dust (EAFD),^[151] while EFAD, slag and fly ash are likely to be more toxic as they contain heavy metals. Besides slag cement that is sold and used as an environmental friendly product,^{[152] [153] [154]} fake (adulterated) cement, where different types of slag, fly ash or other unknown substances are added, is also very common in some places^{[155] [156]} due to the much lower production cost.^[157] To address to the quality^[158] and toxicity problems, some places are starting to ban the use of EAF slag in cement used in buildings.^[159] Composition of welding fumes varies a lot as well and it depends on the metals in the material being welded, the composition of the coatings, electrode, etc., and hence a lot of health problems (e.g., lead poisoning, metal Fume Fever, cancers, nausea, irritation, kidney and liver damage, central nervous system problems, asthma, pneumonia, etc.) can be resulted from the different types of toxic emissions.^[160]

Studies have found that blood lead levels of people in China are highly correlated to ambient PM concentration as well as top soil lead content, indicating that air and soil (e.g., by the inhalation of resuspended soil particles, consuming of contaminated crops or water, etc.) are important sources of lead exposure.^{[161] [162]}

Besides composition, quantity and duration of exposure are also important, since they would affect the triggering and severity of a disease. Particles that get into indoor would directly affect indoor air quality. Possible secondary contamination, similar to third-hand smoke, is also of concern.^{[163] [164]}

In a nutshell, while background concentration is important, only "improvement in air quality" or "decrease in ambient concentration of PM" do not necessarily mean better health. The health impact mainly depends on the toxicity (or source^[165]) of the particulate matter a person is exposed to, the amount he is exposed to and for how long, and also the size, shape, and solubility of the PM.

Since construction and refurbishment projects are prominent sources of particulate matter, it implicates that such projects, which are very common in some places,^{[166] [167]} should be avoided in health facilities that already commenced and under operation as far as possible. For inevitable projects, better plannings and mitigation measures regarding PM emission should be introduced. Use of power tools, heavy equipments, diesel fuels and potentially toxic building materials (e.g. concrete, metals, solder, paint, etc.) should be strictly monitored to ensure that patients who are there seeking for disease treatments or chances to survive are not adversely affected.

Health problems

The effects of inhaling particulate matter that have been widely studied in humans and animals include COVID-19,^{[168] [169] [170] [171] [172]} asthma, lung cancer, respiratory diseases like silicosis,^{[173] [174]} cardiovascular disease, premature delivery, birth defects, low birth weight, developmental disorders,^{[175] [176] [177] [178]} neurodegenerative disorders^{[179] [180]} mental disorders,^{[181] [182] [183]} and premature death. Outdoor fine particulates with diameter less than 2.5 microns accounts for 4.2 million annual deaths worldwide, and more than 103 million disability-adjusted life-years lost, making it the fifth leading risk factor for death. Air pollution has also been linked to a range of other psychosocial problems.^[182] Particulates may cause tissue damage by entering organs directly, or indirectly by systemic inflammation. Adverse effects may occur even at exposure levels lower than published air quality standards deemed safe.^{[184] [185]}

Anthropogenic fine particulates as main hazard

See also: Harvard Six Cities study. Increased levels of fine particles in the air as a result of anthropogenic particulate air pollution "is consistently and independently related to the most serious effects, including lung cancer^[186] and other cardiopulmonary mortality".^[187] The association between a large number of deaths^[188] and other health problems and particulate pollution was first demonstrated in the early 1970s^[189] and has been reproduced many times since. PM pollution is estimated to cause 22,000–52,000 deaths per year in the United States (from 2000)^[190] contributed to ~370,000 premature deaths in Europe during 2005.^[191] and 3.22 million deaths globally in 2010 per the global burden of disease collaboration.^[192] A study by the European Environment Agency estimates that 307,000 people have died prematurely in 2019 due to fine particle pollution in the 27 EU member states.^[193]

A study in 2000 conducted in the U.S. explored how fine particulate matter may be more harmful than coarse particulate matter. The study was based on six different cities. They found that deaths and hospital visits that were caused by particulate matter in the air were primarily due to fine particulate matter.^[194] Similarly, a 1987 study of American air pollution data found that fine particles and sulfates, as opposed to coarser particles, most consistently and significantly correlated to total annual mortality rates in standard metropolitan statistical areas.^[195]

A study published in 2022 in GeoHealth concluded that eliminating energy-related fossil fuel emissions in the United States would prevent 46,900–59,400 premature deaths each year and provide $537–$678 billion in benefits from avoided PM-related illness and death.^[196]

Infertility, pregnancy, fetuses and birth defects

Higher rates of infertility have been correlated with exposure to particulates.^[197] Maternal PM exposure during pregnancy is also associated with high blood pressure in children.^[198]

Inhalation of PM – PM is associated with elevated risk of adverse pregnancy outcomes, such as low birth weight.^[199] Exposure to PM has been associated with greater reductions in birth weight than exposure to PM.^[200] PM exposure can cause inflammation, oxidative stress, endocrine disruption, and impaired oxygen transport access to the placenta,^[201] all of which are mechanisms for heightening the risk of low birth weight.^[202] Overall epidemiologic and toxicological evidence suggests that a causal relationship exists between long-term exposures to PM and developmental outcomes (i.e. low birth weight). Studies investigating the significance of trimester-specific exposure have proven to be inconclusive,^[203] and results of international studies have been inconsistent in drawing associations of prenatal particulate matter exposure and low birth weight. As perinatal outcomes have been associated with lifelong health^{[204] [205]} and exposure to particulate matter is widespread, this issue is of critical public health importance.

Cardiovascular and respiratory disease

See also: Chronic cough. PM leads to high plaque deposits in arteries, causing vascular inflammation and atherosclerosis – a hardening of the arteries that reduces elasticity, which can lead to heart attacks and other cardiovascular problems.^[206] A 2014 meta analysis reported that long term exposure to particulate matter is linked to coronary events. The study included 11 cohorts participating in the European Study of Cohorts for Air Pollution Effects (ESCAPE) with 100,166 participants, followed for an average of 11.5 years. An increase in estimated annual exposure to PM 2.5 of just 5 μg/m was linked with a 13% increased risk of heart attacks.^[207] Not only affecting human cells and tissues, PM also impacts bacteria which cause disease in humans.^[208] Biofilm formation, antibiotic tolerance, and colonisation of both Staphylococcus aureus and Streptococcus pneumoniae was altered by black carbon exposure.

The largest US study on acute health effects of coarse particle pollution between 2.5 and 10 micrometers in diameter was published 2008 and found an association with hospital admissions for cardiovascular diseases but no evidence of an association with the number of hospital admissions for respiratory diseases.^[209] After taking into account fine particle levels (PM and less), the association with coarse particles remained but was no longer statistically significant, which means the effect is due to the subsection of fine particles.

The Mongolian government agency recorded a 45% increase in the rate of respiratory illness in the past five years (reported in 2011).^[210] Bronchial asthma, chronic obstructive pulmonary disease, and interstitial pneumonia were the most common ailments treated by area hospitals. Levels of premature death, chronic bronchitis, and cardiovascular disease are increasing at a rapid rate.

Cognitive hazards and mental health

See also: Manganism and Substance-induced psychosis. The effects of air pollution and particulate matter on cognitive performance has become an active area of research.^[211]

Air pollution may increase the risk of developmental disorders (e.g., autism),^{[175] [176] [177] [178]} neurodegenerative disorders,^{[179] [180]} mental disorders,^{[181] [182] [183]} and suicide,^{[181] [183] [212]} although studies on the link between depression and some air pollutants are not consistent.^[213] At least one study has identified "the abundant presence in the human brain of magnetite nanoparticles that match precisely the high-temperature magnetite nanospheres, formed by combustion and/or friction-derived heating, which are prolific in urban, airborne particulate matter (PM)."^[214]

Particulates also appear to have a role in the pathogenesis of Alzheimer's disease and premature brain aging. There is increasing evidence to suggest a correlation between PM exposure and the prevalence of neurodegenerative diseases such as Alzheimer's. Several epidemiological studies have suggested a link between PM exposure and cognitive decline, particularly in the development of neurodegenerative diseases such as Alzheimer's.

Using geospatial analytical techniques, "NIEHS-funded researchers were able to confirm a strong association between cases of Parkinson's disease and fine particulate matter (known as PM) across the U.S. In the study, regions of the country with a high rate of Parkinson's disease were associated generally with higher levels of PM, of which sources include motor vehicles, wildfires, and power plants."^[215] While the exact mechanisms behind the link between PM exposure and cognitive decline are not fully understood, research suggests that the fine particles may be able to enter the brain through the olfactory nerve and cause inflammation and oxidative stress, which can damage brain cells and contribute to the development of neurodegenerative diseases.^[216]

Increased death

The World Health Organization (WHO) estimated in 2005 that "... fine particulate air pollution (PM(2.5)), causes about 3% of mortality from cardiopulmonary disease, about 5% of mortality from cancer of the trachea, bronchus, and lung, and about 1% of mortality from acute respiratory infections in children under 5 years, worldwide."^[217] A 2011 study concluded that traffic exhaust is the single most serious preventable cause of heart attack in the general public, the cause of 7.4% of all attacks.^[218]

Particulate matter studies in Bangkok, Thailand from 2008 indicated a 1.9% increased risk of dying from cardiovascular disease, and 1.0% risk of all disease for every 10 micrograms per cubic meter. Levels averaged 65 in 1996, 68 in 2002, and 52 in 2004. Decreasing levels may be attributed to conversions of diesel to natural gas combustion as well as improved regulations.^[219]

Racial disparities

There have been many studies linking race to increased proximity to particulate matter, and thus susceptibility to adverse health effects of long term exposure. A U.S. study showed that "the proportions of Black residents in a tract was linked to higher asthma rates".^[220] Many scholars link this disproportionality to racial housing segregation and their respective inequalities in "toxic exposures". This reality is made worse by the finding that "health care occurs in the context of broader historic and contemporary social and economic inequality and persistent racial and ethnic discrimination in many sectors of American life".^[221] Residential proximity to particulate emitting facilities increases exposure to PM 2.5 which is linked to increased morbidity and mortality rates.^[222] Multiple studies confirm the burden of PM emissions is higher among non-White and poverty ridden populations, though some say that income does not drive these differences.^[223] This correlation between race and housing related health repercussions stems from a longstanding environmental justice problem linked to the practice of historic redlining. An example of these factors contextualized is an area of Southeastern Louisiana, colloquially dubbed 'Cancer Alley' for its high concentration of cancer related deaths due to neighboring chemical plants.^[224] Cancer Alley being a majority African American community, with the neighborhood nearest to the plant being 90% Black, perpetuates the scientific narrative that Black populations are located disproportionately closer to areas of high PM output than White populations. A 2020 article relates the long-term health effects of living in high PM concentrations to increased risk, spread, and mortality rates from the SARS-CoV-2 or COVID-19, and faults a history of racism for this outcome.

Wildfire smoke risk

In regions where wildfires are persistent the risk of particulate exposure increased. Smoke from wildfires may impact sensitive groups such as the elderly, children, pregnant women, and people with lung, and cardiovascular disease.^[225] It was found that in the 2008 wildfire season in California, the particulate matter was much more toxic to human lungs, as increased neutrophil infiltrate, cell influx and edema was observed versus particulate matter from ambient air.^[226] Furthermore, particulate matter from wildfires have been linked to be a triggering factor of acute coronary events such as ischemic heart disease.^[227] Wildfires also have been associated with increased emergency department visits due to particulate matter exposure, as well as an increased risk of asthma related events.^{[228] [229]} A link between PM from wildfires and increased risk of hospitalizations for cardiopulmonary diseases has been discovered.^[230] Evidence also suggest wildfire smoke reduces mental performance.^[231]

Energy industry knowledge and response to adverse health effects

Major energy companies understood at least since the 1960s that use of their products causes widespread adverse health effects and death but continued aggressive political lobbying in the United States and elsewhere against clean air regulation and launched major corporate propaganda campaigns to sow doubt regarding the causative link between the burning of fossil fuels and major risks to human life. Internal company memoranda reveal that energy industry scientists and executives knew that air pollutants created by fossil fuels lodge deep in human lung tissue, and cause birth defects in children of oil industry workers. The industry memos acknowledge that automobiles "are by far the greatest sources of air pollution" and also that air pollution causes adverse health effects and lodges toxins, including carcinogens, "deep into the lungs which would otherwise be removed in the throat".^[232]

In response to mounting public concern, the industry eventually created the Global Climate Coalition, an industry lobby group, to derail governments' attempts to regulate air pollution and to create confusion in the public mind about the necessity of such regulation. Similar lobbying and corporate public relations efforts were undertaken by the American Petroleum Institute, a trade association of the oil and gas industry, and the climate change denier private think tank, The Heartland Institute. "The response from fossil-fuel interests has been from the same playbook – first they know, then they scheme, then they deny and then they delay. They've fallen back on delay, subtle forms of propaganda and the undermining of regulation," said Geoffrey Supran, a Harvard University researcher of the history of fossil-fuel companies and climate change. These efforts have been compared, by policy analysts such as Carroll Muffett of the Center for International Environmental Law, to the tobacco industry strategy of lobbying and corporate propaganda campaigns to create doubt regarding the causal connection between cigarette smoking and cancer and to forestall its regulation. In addition, industry-funded advocates, when appointed to senior government positions in the United States, have revised scientific findings showing the deadly effects of air pollution and have rolled back its regulation.^{[232] [233] [234]}

Effects on vegetation

Particulate matter can clog stomatal openings of plants and interfere with photosynthesis functions.^[235] In this manner, high particulate matter concentrations in the atmosphere can lead to growth stunting or mortality in some plant species.

Regulation

Most governments have created regulations both for the emissions allowed from certain types of pollution sources (motor vehicles, industrial emissions etc.) and for the ambient concentration of particulates. The IARC and WHO designate particulates a Group 1 carcinogen. Particulates are the deadliest form of air pollution due to their ability to penetrate deep into the lungs and blood streams unfiltered, causing respiratory diseases, heart attacks, and premature death.^[236] In 2013, the ESCAPE study involving 312,944 people in nine European countries revealed that there was no safe level of particulates and that for every increase of 10 μg/m in PM, the lung cancer rate rose 22%. For PM there was a 36% increase in lung cancer per 10 μg/m.^[186] In a 2014 meta-analysis of 18 studies globally including the ESCAPE data, for every increase of 10 μg/m in PM, the lung cancer rate rose 9%.^[237]

Limits / standards set by governments

Country/ Region	PM		PM		No. of exceedances allowed per year
	Yearly avg.	Daily avg. (24-hour)	Yearly avg.	Daily avg (24-hour)
Australia ^[238]	8	25	25	50
China ^[239]	35	75	70	150
European Union ^[240]	25		40	50	PM: None; PM: 35
Hong Kong ^[241]	35	75	50	100	PM: 9; PM: 9
Japan ^[242] ^[243]	15	35		100
South Korea ^[244] ^[245]	15	35	50	100
Taiwan ^[246] ^[247]	15	35	50	100
United States ^[248]	9	35		150	PM: Not applicable; PM: 1
World Health Organization ^[249]	5	15	15	45	3-4

Canada

In Canada the standard for particulate matter is set nationally by the federal-provincial Canadian Council of Ministers of the Environment (CCME). Jurisdictions (provinces and territories) may set more stringent standards. The CCME standard for particulate matter 2.5 (PM) as of 2015 is 28 μg/m (calculated using the 3-year average of the annual 98th percentile of the daily 24-hr average concentrations) and 10 μg/m³ (3-year average of annual mean). PM standards will increase in stringency in 2020.^[250]

European Union

The European Union has established the European emission standards, which include limits for particulates in the air:^[240]

European Air Quality Index	Good	Fair	Moderate	Poor	Very poor	Extremely poor
Particles less than 2.5μm (PM)	0–10 μg/m	10–20 μg/m	20–25 μg/m	25–50 μg/m	50–75 μg/m	75–800 μg/m
Particles less than 10μm (PM)	0–20 μg/m	20–40 μg/m	40–50 μg/m	50–100 μg/m	100–150 μg/m	150–1200 μg/m

United Kingdom

To mitigate the problem of wood burning, starting from May 2021, traditional house coal (bituminous coal) and wet wood, two of the most polluting fuels, can no longer be sold. Wood sold in volumes of less than 2m³ must be certified as 'Ready to Burn', which means it has a moisture content of 20% or less. Manufactured solid fuels must also be certified as 'Ready to Burn' to ensure they meet sulphur and smoke emission limits.^[251] Starting from January 2022, all new wood burning stoves have to meet new EcoDesign standards (Ecodesign stoves produce 450 times more toxic air pollution than gas central heating. Older stoves, which are now banned from sale, produce 3,700 times more).^[252]

In 2023, the amount of smoke that burners in "smoke control areas" - most England's towns and cities - can emit per hour is reduced from 5g to 3g. Violation will result in an on-the-spot fine of up to £300. Those who do not comply may even get a criminal record.^[253]

United States

The United States Environmental Protection Agency (EPA) has set standards for PM and PM concentrations.^[248] (See National Ambient Air Quality Standards.)

California

In October 2008, the Department of Toxic Substances Control (DTSC), within the California Environmental Protection Agency, announced its intent to request information regarding analytical test methods, fate and transport in the environment, and other relevant information from manufacturers of carbon nanotubes.^[254] DTSC is exercising its authority under the California Health and Safety Code, Chapter 699, sections 57018–57020.^[255] These sections were added as a result of the adoption of Assembly Bill AB 289 (2006). They are intended to make information on the fate and transport, detection and analysis, and other information on chemicals more available. The law places the responsibility to provide this information to the department on those who manufacture or import the chemicals.

On 22 January 2009, a formal information request letter was sent to manufacturers who produce or import carbon nanotubes in California, or who may export carbon nanotubes into the State.^[256] This letter constitutes the first formal implementation of the authorities placed into statute by AB 289 and is directed to manufacturers of carbon nanotubes, both industry, and academia within the State, and to manufacturers outside California who export carbon nanotubes to California. This request for information must be met by the manufacturers within one year. DTSC is waiting for the upcoming 22 January 2010 deadline for responses to the data call-in.

The California Nano Industry Network and DTSC hosted a full-day symposium on 16 November 2009 in Sacramento, California. This symposium provided an opportunity to hear from nanotechnology industry experts and discuss future regulatory considerations in California.^[257]

DTSC is expanding the Specific Chemical Information Call-in to members of the nanometal oxides, the latest information can be found on their website.^[258]

Colorado

Key points in the Colorado Plan include reducing emission levels and solutions by sector. Agriculture, transportation, green electricity, and renewable energy research are the main concepts and goals in this plan. Political programs such as mandatory vehicle emissions testing and the prohibition of smoking indoors are actions taken by local government to create public awareness and participation in cleaner air. The location of Denver next to the Rocky Mountains and wide expanse of plains makes the metro area of Colorado's capital city a likely place for smog and visible air pollution.

Affected areas

To analyse the air pollution trend, 480 cities around the world (Ukraine excluded) was mapped by air experts to calculate the average PM level of the first nine months of 2019 against that of 2022.^[259] Average levels of PM were measured using aqicn.org's World Air Quality Index data, and a formula developed by AirNow was used to convert the PM figure into micrograms per cubic meter of air values.

Among the 70 capital cities investigated, Baghdad, Iraq is the worst performing one, with PM levels going up +31.6 . Ulan Bator (Ulaanbaatar), the capital city of Mongolia, is performing the best, with PM levels dropping by -23.4 . Previously it was as one of the most polluted capital cities in the world. An air quality improvement plan in 2017 appears to be showing positive results.

Out of the 480 cities, Dammam in Saudi Arabia is performing the worst with PM levels going up +111.1 . The city is a significant center for the Saudi oil industry and home to both the largest airport in the world and the largest port in the Persian Gulf. It is currently the most polluted city surveyed.

In Europe, the worst performing cities are located in Spain. They are Salamanca and Palma, with PM levels increase by +5.1  and +3.7  respectively. The best performing city is Skopje, the capital city of North Macedonia, with PM levels dropping by -12.4 . It was once the most polluted capital city in Europe and still has a long way to go to achieve clean air.

In the U.S., Salt Lake City, Utah and Miami, Florida are the two cities with the highest PM level increases (+1.8 ). Salt Lake City suffers from a weather event known as 'inversion'. Located in a valley, cooler, polluted air is trapped close to ground level under the warmer air above when inversion occurs. On the other hand, Omaha, Nebraska is performing the best and has a decrease of -1.1  in PM levels.

The cleanest city in this report is Zürich, Switzerland with PM levels of just 0.5 , placed first in both 2019 and 2022. The second cleanest city is Perth, with 1.7  and PM levels dropping by -6.2  since 2019. Of the top ten cleanest cities, five are from Australia. They are Hobart, Wollongong, Launceston, Sydney and Perth. Honolulu is the only U.S. city in the top ten list, ranking tenth with levels of 4 , with a tiny increase since 2019.

Almost all of the top ten most polluted cities are in the Middle East and Asia. The worst is Dammam in Saudi Arabia with a PM level of 155 . Lahore in Pakistan is the second worst with 98.1 . The third is Dubai, home to the world's tallest building. In the bottom ten are three cities from India, Muzaffarnagar, Delhi and New Delhi. Here is a list of the 30 most polluted cities by PM, Jan to Sep 2022:

City	Country / Region	1st 9 months average PM
		2022	2019
		155	43.9
		98.1	64.6
		97.7	47.5
		60.5	29
		55.3	48.7
		53.9	60.5
		51.6	59.8
		51.1	13.5
		50.1	54.2
		48	43.4
		47.9	53.5
		47	46.7
		46.6	56.9
		46.4	54.1
		46.2	40.4
		45.7	53.3
		44.9	39.7
		43.5	40.6
		42.9	48.3
		42	30
		41.8	18.2
		40.2	44.7
		36.6	40
		36.4	41.4
		36.3	46.4
		36.1	45.9
		36	44.9
		35.9	39.2
		35.9	7.1
		35.5	42.9

There are limits to the above survey. For example, not every city in the world is covered, and that the number of monitoring stations for each city would not be the same. The data is for reference only.

Australia

PM₁₀ pollution in coal mining areas in Australia such as the Latrobe Valley in Victoria and the Hunter Region in New South Wales significantly increased during 2004 to 2014. Although the increase did not significantly add to non-attainment statistics the rate of increase has risen each year during 2010 to 2014.^[260]

China

Some cities in Northern China and South Asia have had concentrations above 200 μg/m.^[261] The PM levels in Chinese cities were extreme between 2010 - 2014, reaching an all-time high in Beijing on 12 January 2013, of 993 μg/m, but has been improving thanks to clean air actions.^{[262] [263]}

To monitor the air quality of south China, the U.S. Consulate Guangzhou set a PM_2.5 and PM₁₀ monitor on Shamian Island in Guangzhou and displays readings on its official website and social platforms.^[264]

Europe

Italy

South Korea

As of 2017, South Korea has the worst air pollution among the developed nations in the OECD (Organization for Economic Cooperation and Development).^[265] According to a study conducted by NASA and NIER, 52% of PM measured in Olympic Park, Seoul in May and June 2016 came from local emissions. The rest was trans-boundary pollution coming from China's Shandong Province (22%), North Korea (9%), Beijing (7%), url=https://english.hani.co.kr/arti/english_edition/e_international/803654.html | title=NASA and NIER study finds that 48% of particulate matter comes from outside S. Korea}} In December 2017, the environmental ministers from South Korea and China signed the China-Korea Environmental Cooperation Plan (2018–22), a five-year plan to jointly solve issues in the air, water, soil and waste. An environmental cooperation centre was also launched in 2018 to aid cooperation.^[266]

Thailand

Air quality of Thailand is getting worse in 2023, which is described as a "post-COVID back-to-normal situation". In addition to the capital Bangkok, air quality in Chiang Mai, a popular tourist destination, is also deteriorating. Chiang Mai was listed as the most polluted city in a live ranking by a Swiss air quality company on 27 March 2023. The ranking includes data from about 100 world cities for which measured PM data is available.^{[267] [268]}

Ulaanbaatar

Mongolia's capital city Ulaanbaatar has an annual average mean temperature of about 0 °C, making it the world's coldest capital city. About 40% of the population lives in apartments, 80% of which are supplied with central heating systems from three combined heat and power plants. In 2007, the power plants consumed almost 3.4 million tons of coal. The pollution control technology is in poor condition.

The other 60% of the population reside in shantytowns (Ger districts), which have developed due to the country's new market economy and the very cold winter seasons. The poor in these districts cook and heat their wood houses with indoor stoves fueled by wood or coal. The resulting air pollution is characterized by raised sulfur dioxide and nitrogen oxide levels and very high concentrations of airborne particles and particulate matter (PM).Annual seasonal average particulate matter concentrations have been recorded as high as 279 μg/m (micrograms per cubic meter). The World Health Organization's recommended annual mean PM level is 20 μg/m,^[269] which means that Ulaanbaatar's PM annual mean levels are 14 times higher than recommended.

During the winter months, in particular, the air pollution obscures the air, affecting the visibility in the city to such an extent that airplanes on some occasions are prevented from landing at the airport.^[270]

In addition to stack emissions, another source unaccounted for in the emission inventory is fly ash from ash ponds, the final disposal place for fly ash that has been collected in settling tanks. Ash ponds are continually eroded by wind during the winter.^[271]

United States

From the "State of Air 2022" report compiled by the American Lung Association using data from the U.S. Environmental Protection Agency from 2018 to 2020,^[272] California cities are the most polluted cities (by PM) in the U.S. while the East Coast is cleaner.

However, another study has come up with a very different conclusion. According to Forbes, a travel insurance comparison site InsureMyTrip conducted a survey of 50 U.S. cities in 2020 and ranked them by cleanliness with criteria like hand sanitizer demand, cleanliness of restaurants, quantity of recycling collectors, satisfaction of garbage disposal, electric vehicle market share and pollution.^[273] On their top ten cleanest cities list, seven are from California, including Long Beach (No. 1), San Diego (No. 2), Sacramento (No. 3), San Jose (No. 6), Oakland (No. 7), Bakersfield (No. 9), and San Francisco (No. 10). The discrepancies maybe due to the differences in data choice, calculation methods, definitions of "cleanliness" and a large variation of air quality across the same state, etc. This again shows that one need to be very careful when drawing conclusions from the many air quality rankings available on the internet.

In mid-2023, air quality in eastern U.S. lowered significantly as particulates from Canada's wildfires blew down. According to NASA, some of the fires were ignited by lightning.^{[274] [275]}

See also

• Air filter
• Air quality index ｜ Air quality law
• ASTDR
• Bioaerosol
• Carbon black
• CCN (Cloud condensation nuclei)
• Chip formation
• Cleanroom
• Contamination control
• Criteria air contaminants
• Dust
• Exposure assessment ｜ Exposure science
• Fertilizer ｜ Pesticides
• Fog ｜ Pea soup fog
• Fugitive dust
• Heavy industry
• List of least polluted cities by particulate matter concentration
• List of most polluted cities by particulate matter concentration
• Metal swarf ｜ Sawdust
• NIEHS
• Non-exhaust emissions
• Occupational dust exposure
• Respirator
• Recycling
• Scrubber
• Suspended solids

Health effects:

• Health effects of coal ash
• Health effects of pesticides
• Health impact of asbestos
• Health impacts of sawdust

Health-related:

• Asthmagen
• Atherosclerosis
• Chronic obstructive pulmonary disease
• Exercise-induced bronchoconstriction
• Pneumoconiosis
• Pulmonary emphysema
• Pulmonary fibrosis

Other names

• atmospheric aerosol particles
• particulate matter (PM)
• suspended particulate matter (SPM)

Further reading

Control

• Web site: Best Practices for Indoor Air Quality when Remodeling Your Home . US EPA. 7 January 2015 .
• Web site: Examples of how to manage dust in the workplace . EPA Victoria.

Health

• News: Air pollution particles found on foetal side of placentas – study. TheGuardian.com. 17 September 2019. Carrington. Damian.
• Liu XQ, Huang J, Song C, Zhang TL, Liu YP, Yu L . Neurodevelopmental toxicity induced by PM Exposure and its possible role in Neurodegenerative and mental disorders . Hum Exp Toxicol . 42 . 9603271231191436 . 2023 . 37537902 . 10.1177/09603271231191436 . 2023HETox..4291436L . 260485784 . .
• InsideEPA.com, Study Links Air Toxics To Heart Disease In Mice Amid EPA Controversy
• G Invernizzi et al., Particulate matter from tobacco versus diesel car exhaust: an educational perspective. Tobacco Control 13, S.219–221 (2004)
• Toxicologic and epidemiologic clues from the characterization of the 1952 London smog fine particulate matter in archival autopsy lung tissues. 2003. 12842775. Hunt. A.. Abraham. J. L.. Judson. B.. Berry. C. L.. Environmental Health Perspectives. 111. 9. 1209–1214. 10.1289/ehp.6114. 1241576.

More

• Web site: Particulate Pollution Course . US EPA. 12 September 2014 .
• Voiland, Adam. "Aerosols: Tiny Particles, Big Impact." NASA, 2 November 2010, Aerosols: Tiny Particles, Big Impact
• The Intergovernmental Panel on Climate Change (the principal international scientific body on climate change) chapter on atmospheric aerosols and their radiative effects
• Preining, Othmar and E. James Davis (eds.), "History of Aerosol Science," Österreichische Akademie der Wissenschaften, (Pbk.)
• Jelonek Z, Drobniak A, Mastalerz M, Jelonek I . Environmental implications of the quality of charcoal briquettes and lump charcoal used for grilling . Sci Total Environ . 747 . 141267 . December 2020 . 32777507 . 10.1016/j.scitotenv.2020.141267. 2020ScTEn.74741267J . 221100463 .
• Hinds, William C., Aerosol Technology: Properties, Behavior, and Measurement of Airborne Particles, Wiley-Interscience,
• Zangari, Shelby et al., Air quality changes in New York City during the COVID-19 pandemic. Science of the Total Environment 742 (2020)
• NARSTO (2004) Particulate Matter Science for Policy Makers: A NARSTO Assessment. P. McMurry, M. Shepherd, and J. Vickery, eds. Cambridge University Press, Cambridge, England. .
• Web site: 70 years since the great London smog 1952, air quality in a modern context. 5 December 2022.
• Web site: A Major Source of Air Pollution: Farms - The Earth Institute.
• Web site: Hong Kong's illegal barbecue site something to chew on South China Morning Post. 4 December 2021 .
• Outdoor charcoal grilling: Particulate and gas-phase emissions, organic speciation and ecotoxicological assessment - ScienceDirect. Atmospheric Environment . 15 September 2022 . 285 . 119240 . 10.1016/j.atmosenv.2022.119240 . Alves . Célia A. . Evtyugina . Margarita . Vicente . Estela . Vicente . Ana . Gonçalves . Cátia . Neto . Ana Isabel . Nunes . Teresa . Kováts . Nora . 249860528 .
• Aerosol optical depth regime over megacities of the world . 2022 . 10.5194/acp-22-15703-2022 . free . Papachristopoulou . Kyriakoula . Raptis . Ioannis-Panagiotis . Gkikas . Antonis . Fountoulakis . Ilias . Masoom . Akriti . Kazadzis . Stelios . Atmospheric Chemistry and Physics . 22 . 24 . 15703–15727 . 2022ACP....2215703P .
• Air pollution helps wildfires create their own lightning. 2021 . 10.1126/science.abj6782 . Ogasa . Nikk . Science . 236389007 .
• Web site: The Weight of Numbers: Air Pollution and PM . Undark Magazine . 2019-09-27.
• JEFF CHARLTON Pandemic planning: a review of respirator and mask protection levels.

External links

Control

• Control of dust from construction and demolition activities
• Controlling construction dust with on-tool extraction (4 page PDF with photos)
• Beware of dust - Hilti Canada | Dust control - Hilti Hong Kong
• What is Local Exhaust Ventilation (LEV)?
• Welding fume: protect your workers
• Environmental Toolbox Training Kit from the Hong Kong Construction Association with many illustrated useful tips on particle pollution control. Archived from original on 3 July 2023.

Others

• NASA's Earth Minute: My Name is Aerosol
• SARS-CoV-2 Aerosol Mechanisms, The Aerosol Society
• Current global map of PM distribution | Current global map of PM and PM distribution | Current global map of PM, PM and PM distribution
• Current global map of the aerosol optical thickness of organic matter in green light
• Real time air quality | About
• Air quality map | About
• Pollution Facts by Air Quality Life Index
• Health Effects of Air Pollutants. EPD HK. *Archived from original on 5 January 2014.
• Sources of Respirable and Fine Suspended Particulates. EPD HK. *Archived from original on 21 September 2024.
• Precision Environmental Health's role in preventing disease

Notes and References

1. Book: Seinfeld J, Pandis S . Atmospheric Chemistry and Physics: From Air Pollution to Climate Change . 2nd . . 1998 . Hoboken, New Jersey . 978-0-471-17816-3 . 97 . registration .
2. Plainiotis S, Pericleous KA, Fisher BE, Shier L . January 2010 . Application of Lagrangian particle dispersion models to air quality assessment in the Trans-Manche region of Nord-Pas-de-Calais (France) and Kent (Great Britain) . International Journal of Environment and Pollution . 40 . 1/2/3 . 160–74 . 10.1504/IJEP.2010.030891 .
3. Brown JS, Gordon T, Price O, Asgharian B . Thoracic and respirable particle definitions for human health risk assessment . Particle and Fibre Toxicology . 10 . 12 . April 2013 . 23575443 . 3640939 . 10.1186/1743-8977-10-12 . free .
4. Web site: US EPA . OAR . Particulate Matter (PM) Basics . US EPA . 5 October 2019 . 19 April 2016.
5. Web site: EHP – Outdoor Particulate Matter Exposure and Lung Cancer: A Systematic Review and Meta-Analysis. ehp.niehs.nih.gov. 2016-12-29. https://web.archive.org/web/20160529064001/http://ehp.niehs.nih.gov/1408092/. 29 May 2016. dead.
6. News: Wasley . Andrew . Heal . Alexandra . Harvey . Fiona . Lainio . Mie . Revealed: UK government failing to tackle rise of serious air pollutant . The Guardian . 13 June 2019 .
7. Thangavel . Prakash . Park . Duckshin . Lee . Young-Chul . 2022-06-19 . Recent Insights into Particulate Matter (PM2.5)-Mediated Toxicity in Humans: An Overview . International Journal of Environmental Research and Public Health . en . 19 . 12 . 7511 . 10.3390/ijerph19127511 . free . 35742761 . 9223652 . 1660-4601.
8. Web site: STATE OF GLOBAL AIR/2018 A SPECIAL REPORT ON GLOBAL EXPOSURE TO AIR POLLUTION AND ITS DISEASE BURDEN. Health Effects Institute. 2018.
9. News: The Weight of Numbers: Air Pollution and PM_2.5. Undark. 6 September 2018.
10. Omidvarborna . Recent studies on soot modeling for diesel combustion . Renewable and Sustainable Energy Reviews . 48 . 635–647 . 10.1016/j.rser.2015.04.019 . etal. 2015 . 2015RSERv..48..635O .
11. Web site: Air quality, EASA Eco.
12. Lin C, Huang RJ, Duan J, Zhong H, Xu W, Wu Y, Zhang R . Large contribution from worship activities to the atmospheric soot particles in northwest China . Environ Pollut . 299 . 118907 . April 2022 . 35091017 . 10.1016/j.envpol.2022.118907 . 2022EPoll.29918907L . 246355499 .
13. Heavy metals emissions from joss paper burning rituals and the air quality around a specific incinerator. 2021 . 10.1016/j.matpr.2020.08.686 . Giang . Lam Van . Thanh . Tran . Hien . Truong Thanh . Tan . Lam Van . Thi Bich Phuong . Tran . Huu Loc . Ho . Materials Today: Proceedings . 38 . 2751–2757 . 226353498 .
14. Shen H, Tsai CM, Yuan CS, Jen YH, Ie IR . How incense and joss paper burning during the worship activities influences ambient mercury concentrations in indoor and outdoor environments of an Asian temple? . Chemosphere . 167 . 530–540 . January 2017 . 27764746 . 10.1016/j.chemosphere.2016.09.159 . 2017Chmsp.167..530S .
15. Potential Risks of Open Waste Burning at the Household Level: A Case Study of Semarang, Indonesia . Ramadan . Bimastyaji Surya . Rosmalina . Raden Tina . Syafrudin . Munawir . Khair . Hafizhul . Rachman . Indriyani . Matsumoto . Toru . Aerosol and Air Quality Research . Taiwan Association for Aerosol Research . 23 . 5 . 2023 . 1680-8584 . 10.4209/aaqr.220412 . 220412. 257202752 .
16. Shah R, Limaye S, Ujagare D, Madas S, Salvi S . Personal exposures to particulate matter <2.5 μm in mass median aerodynamic diameter (PM) pollution during the burning of six most commonly used firecrackers in India . Lung India . 36 . 4 . 324–329 . 2019 . 31290418 . 6625239 . 10.4103/lungindia.lungindia_440_18 . free .
17. Roy . Rajarshi . Schooff . Brian . Li . Xiaolong . Montgomery . Scott . Tuttle . Jacob . Wendt . Jost O. L. . Dickson . Kingsley . Iverson . Brian . Fry . Andrew . Ash aerosol particle size distribution, composition, and deposition behavior while co-firing coal and steam-exploded biomass in a 1.5 MWth combustor . Fuel Processing Technology . 1 May 2023 . 243 . 107674 . 10.1016/j.fuproc.2023.107674. 256529257 .
18. Ambient exposure to coarse and fine particle emissions from building demolition. 2016. 10.1016/j.atmosenv.2016.04.029. Azarmi. Farhad. Kumar. Prashant. Atmospheric Environment. 137. 62–79. 2016AtmEn.137...62A.
19. Web site: Emissions of air pollutants in the UK – Particulate matter (PM and PM).
20. Web site: Building works responsible for 18% of UK large particle pollution.
21. Web site: Delhi's deadly dust: how construction sites are choking the city.
22. Web site: Particulate matter emissions from activities of building refurbishment.
23. Web site: 一家三口中鉛毒 疑含鉛船用油漆髹浴室門所致 衛生署提家中裝修注意事項 (14:05) . 明報新聞網 - 即時新聞 instant news . Jun 2024 . zh-hant.
24. Web site: SF Concrete Plant That Was Focus of NBC Bay Area Investigative Report, Ordered to Shut Down. 11 March 2022.
25. Scoop, pollution at Yau Tong Cement batching plant. HK. TVB.
26. Orirental Daily News once again revealed that the Yau Tong Concrete Plant violated regulations and emitted a large amount of smoke and dust, up to 40 meters . HK. Oriental Daily News.
27. Kholodov A, Zakharenko A, Drozd V, Chernyshev V, Kirichenko K, Seryodkin I, Karabtsov A, Olesik S, Khvost E, Vakhnyuk I, Chaika V, Stratidakis A, Vinceti M, Sarigiannis D, Hayes AW, Tsatsakis A, Golokhvast K . Identification of cement in atmospheric particulate matter using the hybrid method of laser diffraction analysis and Raman spectroscopy . Heliyon . 6 . 2 . e03299 . February 2020 . 32128461 . 7042420 . 10.1016/j.heliyon.2020.e03299 . free . 2020Heliy...603299K .
28. Web site: Cut down construction dust.
29. Web site: Proper Covering of Dusty Material on Dump Trucks . www.epd.gov.hk.
30. Web site: Dusty Material - an overview | ScienceDirect Topics. www.sciencedirect.com.
31. Kim JY, Chen JC, Boyce PD, Christiani DC . Exposure to welding fumes is associated with acute systemic inflammatory responses . Occup Environ Med . 62 . 3 . 157–63 . March 2005 . 15723880 . 1740976 . 10.1136/oem.2004.014795 .
32. Bruschweiler ED, Danuser B, Huynh CK, Wild P, Schupfer P, Vernez D, Boiteux P, Hopf NB . Generation of polycyclic aromatic hydrocarbons (PAHs) during woodworking operations . Front Oncol . 2 . 148 . 2012 . 23087908 . 3475003 . 10.3389/fonc.2012.00148 . free .
33. Web site: Woodworking health topics - Inhaling wood dust.
34. Patel . Sameer . Sankhyan . Sumit . Boedicker . Erin K. . DeCarlo . Peter F. . Farmer . Delphine K. . Goldstein . Allen H. . Katz . Erin F. . Nazaroff . William W . Tian . Yilin . Vanhanen . Joonas . Vance . Marina E. . June 16, 2020 . Indoor Particulate Matter during HOMEChem: Concentrations, Size Distributions, and Exposures . live . Environmental Science & Technology . en . 54 . 12 . 7107–7116 . 2020EnST...54.7107P . 10.1021/acs.est.0c00740 . 0013-936X . 32391692 . https://web.archive.org/web/20230428153441/https://pubs.acs.org/doi/10.1021/acs.est.0c00740 . April 28, 2023 . April 11, 2024.
35. Web site: Dust advice for businesses - EPA Victoria.
36. Henneman L, Choirat C, Dedoussi I, Dominici F, Roberts J, Zigler C . Mortality risk from United States coal electricity generation . Science . 382 . 6673 . 941–946 . November 2023 . 37995235 . 10870829 . 10.1126/science.adf4915 . 2023Sci...382..941H .
37. Lin Y, Zou J, Yang W, Li CQ . A Review of Recent Advances in Research on PM_2.5in China . Int J Environ Res Public Health . 15 . 3 . March 2018 . 438 . 29498704 . 5876983 . 10.3390/ijerph15030438 . free .
38. Sharma R, Sharma M, Sharma R, Sharma V . The impact of incinerators on human health and environment . Rev Environ Health . 28 . 1 . 67–72 . 2013 . 23612530 . 10.1515/reveh-2012-0035 . 21271240 .
39. Book: 10.1787/4a4dc6ca-en . Non-exhaust Particulate Emissions from Road Transport . 2020 . OECD . 978-92-64-88885-2 . 136987659 .
40. Khan RK, Strand MA . Road dust and its effect on human health: a literature review . Epidemiol Health . 40 . e2018013 . 2018 . 29642653 . 5968206 . 10.4178/epih.e2018013 .
41. Respirable nano-particulate generations and their pathogenesis in mining workplaces: a review. 2021. 10.1007/s40789-021-00412-w. Fan. Long. Liu. Shimin. International Journal of Coal Science & Technology. 8. 2. 179–198. 233890096.
42. Particulates from mining operations: A review of sources, effects and regulations. 2005. 10.1016/j.mineng.2005.06.017. Petavratzi. E.. Kingman. S.. Lowndes. I.. Minerals Engineering. 18. 12. 1183–1199. 2005MiEng..18.1183P.
43. Jeong H, Choi JY, Ra K . Potentially toxic elements pollution in road deposited sediments around the active smelting industry of Korea . Sci Rep . 11 . 1 . 7238 . March 2021 . 33790361 . 8012626 . 10.1038/s41598-021-86698-x .
44. News: Harmful soot unchecked as Big Oil battles EPA over testing. Reuters. 6 January 2022. McLaughlin. Tim.
45. Book: 7121041. Chandrappa. R.. Chandra Kulshrestha. U.. Sustainable Air Pollution Management. Air Pollution and Disasters. Environmental Science and Engineering. 2016. 325–343. 10.1007/978-3-319-21596-9_8. 978-3-319-21595-2.
46. Web site: Sand, Dust and Particulates Public Health.
47. WarImpact on Air Quality in Ukraine. 2022. 10.3390/su142113832. free. Zalakeviciute. Rasa. Mejia. Danilo. Alvarez. Hermel. Bermeo. Xavier. Bonilla-Bedoya. Santiago. Rybarczyk. Yves. Lamb. Brian. Sustainability. 14. 21. 13832.
48. Xie Y, Li Y, Feng Y, Cheng W, Wang Y . Inhalable microplastics prevails in air: Exploring the size detection limit . Environ Int . 162 . 107151 . April 2022 . 35228011 . 10.1016/j.envint.2022.107151 . 2022EnInt.16207151X .
49. Liu C, Li J, Zhang Y, Wang L, Deng J, Gao Y, Yu L, Zhang J, Sun H . Widespread distribution of PET and PC microplastics in dust in urban China and their estimated human exposure . Environ Int . 128 . 116–124 . July 2019 . 31039519 . 10.1016/j.envint.2019.04.024 . 2019EnInt.128..116L .
50. Web site: Aerosols and Climate Change . Hardin M, Kahn R . 2 November 2010 .
51. Web site: Emissions of air pollutants. 22 February 2023 .
52. Hawkes N . Air pollution in UK: the public health problem that won't go away . BMJ . 350 . h2757 . May 2015 . 26001592 . 10.1136/bmj.h2757 . 40717317 .
53. Web site: Carrington. Damian. 2021-02-16. Wood burning at home now biggest cause of UK particle pollution. 2022-02-13. The Guardian. en.
54. Web site: Wood burning heaters and your health - Fact sheets.
55. Web site: How to choose and maintain a wood heater - EPA Victoria.
56. Web site: How to choose the right wood for your wood heater - EPA Victoria.
57. Web site: How to light and maintain your wood heater fire - EPA Victoria.
58. Web site: Smoke and the law - EPA Victoria.
59. Web site: Primary and Secondary Sources of Aerosols: Soil dust . Climate Change 2001: Working Group 1 . UNEP . 2001 . 6 February 2008 . https://web.archive.org/web/20080228174319/http://www.grida.no/climate/ipcc_tar/wg1/168.htm#5221 . 28 February 2008 . dead .
60. Perraud V, Bruns EA, Ezell MJ, Johnson SN, Yu Y, Alexander ML, Zelenyuk A, Imre D, Chang WL, Dabdub D, Pankow JF, Finlayson-Pitts BJ . 6 . Nonequilibrium atmospheric secondary organic aerosol formation and growth . Proceedings of the National Academy of Sciences of the United States of America . 109 . 8 . 2836–41 . February 2012 . 22308444 . 3286997 . 10.1073/pnas.1119909109 . 2012PNAS..109.2836P . free .
61. Web site: Primary and Secondary Sources of Aerosols: Sea salt . Climate Change 2001: Working Group 1 . UNEP . 2001 . 6 February 2008 . https://web.archive.org/web/20080228174324/http://www.grida.no/climate/ipcc_tar/wg1/169.htm#5222 . 28 February 2008 . dead .
62. Sea Spray Aerosol: Where Marine Biology Meets Atmospheric Chemistry. 2018. 6311946. Schiffer. J. M.. Mael. L. E.. Prather. K. A.. Amaro. R. E.. Grassian. V. H.. ACS Central Science. 4. 12. 1617–1623. 10.1021/acscentsci.8b00674. 30648145.
63. Int Panis LL . The Effect of Changing Background Emissions on External Cost Estimates for Secondary Particulates . Open Environmental Sciences . 2 . 47–53 . 2008 . 10.2174/1876325100802010047. free .
64. Web site: Primary and Secondary Sources of Aerosols: Primary biogenic aerosols . Climate Change 2001: Working Group 1 . UNEP . 2001 . 6 February 2008 . https://web.archive.org/web/20080228174330/http://www.grida.no/climate/ipcc_tar/wg1/172.htm#5226 . 28 February 2008 . dead .
65. News: Scientists Find New Dangers in Tiny but Pervasive Particles in Air Pollution . 19 February 2012 . The New York Times . 18 February 2012 . Felicity . Barringer.
66. Web site: Mongolia: Air Pollution in Ulaanbaatar – Initial Assessment of Current Situations and Effects of Abatement Measures. The World Bank. 2010. https://web.archive.org/web/20160919230954/http://documents.worldbank.org/curated/en/866561468274261208/pdf/529700REPLACEM1paper0FINAL002110110.pdf. dead. 2016-09-19.
67. Web site: An American Aerosol in Paris. 15 September 2017.
68. Book: http://papers.sae.org/2013-01-2741/. Behaviour Study of Particulate Matter and Chemical Composition with Different Combustion Strategies. 2016-06-17. 10.4271/2013-01-2741. SAE Technical Paper Series. 1. 2013. Goswami A, Barman J, Rajput K, Lakhlani HN .
69. Web site: Effect Of Particulate Matter On Plants Climate, Ecosystem and Human Health. April 2014. 3 February 2016. www.ijates.com .
70. Web site: What are PM filters and why are they effective? . Puraka Masks .
71. Effect of Inlet Air Volumetric Flow Rate on the Performance of a Two-Stage Cyclone Separator. 2018. 6644756. Chen. J.. Jiang. Z. A.. Chen. J.. ACS Omega. 3. 10. 13219–13226. 10.1021/acsomega.8b02043. 31458040.
72. Web site: The Encyclopedia of Dust Collection . Dominick DalSanto. February 2011 .
73. Web site: Monitoring by Control Technique - Wet Scrubber For Particulate Matter. 25 May 2016.
74. Web site: Monitoring by Control Technique - Electrostatic Precipitators. 24 May 2016.
75. Web site: Enforcement Activities and Statistics under the Air Pollution Control Ordinance and the Ozone Layer Protection Ordinance 2021.
76. Web site: Construction contractor fined for carrying out building demolition work in Shek O without appropriate dust control measures.
77. Web site: Pollution Problems & Practical Solutions.
78. Web site: Delhi Govt To Impose Fines On Violation Of Anti-Dust Norms. 6 October 2022.
79. Web site: Management Regulations for Construction Project Air Pollution Control Facilities.
80. Web site: Revised GRAP to deal with adverse air quality scenario.
81. Web site: Achievements in environmental pollution control on construction activities, 2004.
82. Web site: Particulate Matter in the United Kingdom Summary . Air Quality Expert Group . Defra . 28 June 2023 . 2005.
83. Web site: Condensation particle counters . Center for Atmospheric Science . University of Manchester . 5 July 2023.
84. Web site: Particle Numbers and Concentrations Network- Defra, UK. Food and Rural Affairs (Defra) webmaster@defra gsi gov uk. Department for Environment. uk-air.defra.gov.uk.
85. Gilfrich. J. Burkhalter. P. Birks. L. X-ray spectrometry for particulate air pollution—a quantitative comparison of techniques. . Anal Chem . 1973 . 45 . 12 . 2002–9 . 4762375 . 10.1021/ac60334a033 .
86. Haywood . James . Boucher . Olivier . Estimates of the direct and indirect radiative forcing due to tropospheric aerosols: A review . Reviews of Geophysics . November 2000 . 38 . 4 . 513–543 . 10.1029/1999RG000078 . 2000RvGeo..38..513H . 129107853 .
87. Twomey S . 1977. The influence of pollution on the shortwave albedo of clouds. Journal of the Atmospheric Sciences. 34. 7. 1149–1152. 10.1175/1520-0469(1977)034<1149:TIOPOT>2.0.CO;2. 1977JAtS...34.1149T . free.
88. Web site: 6.7.8 Discussion of Uncertainties. https://web.archive.org/web/20020228024246/http://www.grida.no/climate/ipcc_tar/wg1/237.htm#678. dead. 28 February 2002. IPCC Third Assessment Report – Climate Change 2001. 14 July 2012.
89. Charlson RJ, Schwartz SE, Hales JM, Cess RD, Coakley JA, Hansen JE, Hofmann DJ . Climate forcing by anthropogenic aerosols . Science . 255 . 5043 . 423–30 . January 1992 . 17842894 . 10.1126/science.255.5043.423 . 26740611 . 1992Sci...255..423C .
90. Book: Forster P, Ramaswamy V, Artaxo P, Berntsen T, Betts R, Fahey DW, Haywood J . Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change in Climate Change 2007: The Physical Science Basis . Solomon S, Qin D, Manning M, Chen Z, Marquis M, Averyt KB, Tignor M, Miller HL . 129–234. Cambridge University Press. Cambridge, United Kingdom and New York, NY, US. http://elib.dlr.de/51416/ . Changes in Atmospheric Constituents and in Radiative Forcing . etal. October 2007.
91. Ackerman AS, Toon OB, Taylor JP, Johnson DW, Hobbs PV, Ferek RJ . 2000. Effects of Aerosols on Cloud Albedo: Evaluation of Twomey's Parameterization of Cloud Susceptibility Using Measurements of Ship Tracks. Journal of the Atmospheric Sciences. 57. 16 . 2684–2695 . 10.1175/1520-0469(2000)057<2684:EOAOCA>2.0.CO;2. 2000JAtS...57.2684A .
92. Kaufman YJ, Fraser RS . 1997. The Effect of Smoke Particles on Clouds and Climate Forcing. Science. 277 . 5332 . 1636–1639 . 10.1126/science.277.5332.1636.
93. Ferek RJ, Garrett T, Hobbs PV, Strader S, Johnson D, Taylor JP, Nielsen K, Ackerman AS, Kogan Y, Liu Q, Albrecht BA . 2000 . Drizzle Suppression in Ship Tracks . Journal of the Atmospheric Sciences . 57 . 16 . 2707–2728 . 10.1175/1520-0469(2000)057<2707:DSIST>2.0.CO;2 . 2000JAtS...57.2707F . etal . 10945/46780 . 40273867 .
94. Rosenfeld D . 1999. TRMM observed first direct evidence of smoke from forest fires inhibiting rainfall. Geophysical Research Letters. 26 . 20 . 3105–3108. 10.1029/1999GL006066 . 1999GeoRL..26.3105R. free.
95. Hansen J, Sato M, Ruedy R . 1997. Radiative forcing and climate response. Journal of Geophysical Research . 102 . D6 . 6831–6864 . 10.1029/96JD03436 . 1997JGR...102.6831H. free .
96. Ackerman AS, Toon OB, Stevens DE, Heymsfield AJ, Ramanathan V, Welton EJ . Reduction of tropical cloudiness by soot . Science . 288 . 5468 . 1042–7 . May 2000 . 10807573 . 10.1126/science.288.5468.1042 . 2000Sci...288.1042A .
97. Koren I, Kaufman YJ, Remer LA, Martins JV . Measurement of the effect of Amazon smoke on inhibition of cloud formation . Science . 303 . 5662 . 1342–5 . February 2004 . 14988557 . 10.1126/science.1089424 . 37347993 . 2004Sci...303.1342K .
98. Riva . Matthieu . Chen . Yuzhi . Zhang . Yue . Lei . Ziying . Olson . Nicole E. . Boyer . Hallie C. . Narayan . Shweta . Yee . Lindsay D. . Green . Hilary S. . Cui . Tianqu . Zhang . Zhenfa . Baumann . Karsten . Fort . Mike . Edgerton . Eric . Budisulistiorini . Sri H. . 2019-08-06 . Increasing Isoprene Epoxydiol-to-Inorganic Sulfate Aerosol Ratio Results in Extensive Conversion of Inorganic Sulfate to Organosulfur Forms: Implications for Aerosol Physicochemical Properties . Environmental Science & Technology . en . 53 . 15 . 8682–8694 . 10.1021/acs.est.9b01019 . 0013-936X . 6823602 . 31335134. 2019EnST...53.8682R .
99. Seinfeld, John H.; Pandis, Spyros N (1998). Atmospheric Chemistry and Physics — From Air Pollution to Climate Change. John Wiley and Sons, Inc.
100. Charlson . Robert J. . Wigley . Tom M. L. . 1994 . Sulfate Aerosol and Climatic Change . Scientific American . 270 . 2 . 48–57 . 10.1038/scientificamerican0294-48 . 24942590 . 1994SciAm.270b..48C . 0036-8733.
101. Legras . Bernard . Duchamp . Clair . Sellitto . Pasquale . Podglajen . Aurélien . Carboni . Elisa . Siddans . Richard . Grooß . Jens-Uwe . Khaykin . Sergey . Ploeger . Felix . 23 November 2022 . The evolution and dynamics of the Hunga Tonga plume in the stratosphere . Atmospheric Chemistry and Physics . English . 22 . 22 . 14957–14970 . 10.5194/acp-22-14957-2022. 253875202 . free .
102. Web site: Allen . Bob . 2015-04-06 . Atmospheric Aerosols: What Are They, and Why Are They So Important? . 2023-04-17 . NASA.
103. IPCC, 1990: Chapter 1: Greenhouse Gases and Aerosols [R.T. Watson, H. Rodhe, H. Oeschger and U. Siegenthaler]. In: Climate Change: The IPCC Scientific Assessment [J.T.Houghton, G.J.Jenkins and J.J.Ephraums (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 31–34,
104. Web site: Effects of Acid Rain - Surface Waters and Aquatic Animals. dead. https://web.archive.org/web/20090514121649/http://www.epa.gov/acidrain/effects/surface_water.html. 14 May 2009. US EPA.
105. 10.1126/science.272.5259.244. Long-Term Effects of Acid Rain: Response and Recovery of a Forest Ecosystem. 1996. Likens. G. E.. Driscoll. C. T.. Buso. D. C.. Science. 272. 5259. 244. 1996Sci...272..244L . 178546205. February 9, 2013. December 24, 2012. https://web.archive.org/web/20121224203613/http://www.esf.edu/efb/mitchell/Class%20Readings/Sci.272.244.246.pdf. live.
106. http://www.epa.gov/acidrain/effects/health.html Effects of Acid Rain – Human Health
107. Wang . X. . Ding . H. . Ryan . L. . Xu . X. . 2707126 . 1 May 1997 . Association between air pollution and low birth weight: a community-based study . Environmental Health Perspectives . 105 . 5 . 514–20 . 0091-6765 . 1469882 . 9222137 . 10.1289/ehp.97105514.
108. Effect of sulfate aerosol on tropospheric NOx and ozone budgets: Model simulations and TOPSE evidence . Tie . X. . 2003 . J. Geophys. Res. . 108 . D4 . 8364 . 10.1029/2001JD001508 . 2003JGRD..108.8364T . etal . free .
109. https://www.sciencedaily.com/releases/1998/09/980928072644.htm Clean Air Act Reduces Acid Rain In Eastern United States
110. Web site: 2007-03-17 . 2007-03-17 . https://web.archive.org/web/20070317212933/http://www.epa.gov/airtrends/econ-emissions.html . Air Emissions Trends – Continued Progress Through 2005 . . 8 July 2014.
111. Web site: Moses. Elizabeth. Cardenas . Beatriz. Seddon. Jessica. 25 February 2020. The Most Successful Air Pollution Treaty You've Never Heard Of . en.
112. Stanhill, G. . S. Cohen. Global dimming: a review of the evidence for a widespread and significant reduction in global radiation with discussion of its probable causes and possible agricultural consequences . Agricultural and Forest Meteorology. 107. 2001. 4 . 10.1016/S0168-1923(00)00241-0. 255–278 . 2001AgFM..107..255S.
113. News: Global 'Sunscreen' Has Likely Thinned, Report NASA Scientists. NASA. 15 March 2007. 28 June 2023. 22 December 2018. https://web.archive.org/web/20181222142212/https://www.nasa.gov/centers/goddard/news/topstory/2007/aerosol_dimming.html. dead.
114. News: 2017. A bright sun today? It's down to the atmosphere. The Guardian. 2017-05-19. 2017-05-20. https://web.archive.org/web/20170520010323/https://www.theguardian.com/news/2017/mar/21/a-bright-sun-today-its-down-to-the-atmosphere. live.
115. Seneviratne . S.I. . Zhang . X. . Adnan . M. . Badi . W. . Dereczynski . C. . Di Luca . A. . Ghosh . S. . Iskandar . I. . Kossin . J. . Lewis . S. . Otto . F. . Pinto . I. . Satoh . M. . Vicente-Serrano . S. M. . Wehner . M. . Zhou . B. . Masson-Delmotte . V. . Zhai . P. . Piran . A. . Connors . S.L. . Péan . C. . Berger . S. . Caud . N. . Chen . Y. . Goldfarb . L. . Weather and Climate Extreme Events in a Changing Climate . Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change . 2021 . 2021 . 1238 . 10.1017/9781009157896.007. 2021AGUFM.U13B..05K .
116. Gillett . Nathan P. . Kirchmeier-Young . Megan . Ribes . Aurélien . Shiogama . Hideo . Hegerl . Gabriele C. . Knutti . Reto . Gastineau . Guillaume . John . Jasmin G. . Li . Lijuan . Nazarenko . Larissa . Rosenbloom . Nan . Seland . Øyvind . Wu . Tongwen . Yukimoto . Seiji . Ziehn . Tilo . Constraining human contributions to observed warming since the pre-industrial period . 18 January 2021 . Nature Climate Change . 11. 3 . 207–212. 10.1038/s41558-020-00965-9 . 2021NatCC..11..207G . 231670652 .
117. IPCC, 2021: Summary for Policymakers. In: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Masson-Delmotte, V., P. Zhai, A. Pirani, S.L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. Matthews, T.K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, and B. Zhou (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 3–32, .
118. News: Andrew . Tawana . Behind the Forecast: How clouds affect temperatures . 4 January 2023 . Science Behind the Forecast . LOUISVILLE, Ky. (WAVE) . 27 September 2019 . en.
119. McCoy . Daniel T. . Field . Paul . Gordon . Hamish . Elsaesser . Gregory S. . Grosvenor . Daniel P. . 6 April 2020 . Untangling causality in midlatitude aerosol–cloud adjustments . Atmospheric Chemistry and Physics . 20 . 7 . 4085–4103 . 10.5194/acp-20-4085-2020 . 2020ACP....20.4085M . free .
120. Rosenfeld . Daniel . Zhu . Yannian . Wang . Minghuai . Zheng . Youtong . Goren . Tom . Yu . Shaocai . 2019 . Aerosol-driven droplet concentrations dominate coverage and water of oceanic low level clouds . Science . 363. 6427. eaav0566. 10.1126/science.aav0566 . 30655446 . 58612273 . free .
121. Glassmeier . Franziska . Hoffmann . Fabian . Johnson . Jill S. . Yamaguchi . Takanobu . Carslaw . Ken S. . Feingold . Graham . 29 January 2021 . Aerosol-cloud-climate cooling overestimated by ship-track data . Science . 371 . 6528 . 485–489 . 10.1126/science.abd3980 . 33510021 . 2021Sci...371..485G . free .
122. Manshausen . Peter . Watson-Parris . Duncan . Christensen . Matthew W. . Jalkanen . Jukka-Pekka . Stier . Philip Stier . 7 March 2018 . Invisible ship tracks show large cloud sensitivity to aerosol . Nature . 610 . 7930 . 101–106 . 10.1038/s41586-022-05122-0 . 36198778 . 9534750 . free .
123. Jongebloed . U. A. . Schauer . A. J. . Cole-Dai . J. . Larrick . C. G. . Wood . R. . Fischer . T. P. . Carn . S. A. . Salimi . S. . Edouard . S. R. . Zhai . S. . Geng . L. . Alexander . B. . Underestimated Passive Volcanic Sulfur Degassing Implies Overestimated Anthropogenic Aerosol Forcing . 2 January 2023 . Geophysical Research Letters . 50 . 1 . e2022GL102061 . 10.1029/2022GL102061 . 2023GeoRL..5002061J . 255571342 .
124. Visioni . Daniele . Slessarev . Eric . MacMartin . Douglas G . Mahowald . Natalie M . Goodale . Christine L . Christine Goodale . Xia . Lili . 1 September 2020 . What goes up must come down: impacts of deposition in a sulfate geoengineering scenario . Environmental Research Letters . 15 . 9 . 094063 . 2020ERL....15i4063V . 10.1088/1748-9326/ab94eb . 1748-9326 . free.
125. Web site: Costs and benefits of geo-engineering in the Stratosphere . Andrew Charlton-Perez . Eleanor Highwood . amp . 17 February 2009 . 14 January 2017 . https://web.archive.org/web/20170114032949/http://www.met.reading.ac.uk/pg-research/downloads/2009/pgr-charlton.pdf . dead .
126. Trisos . Christopher H. . Geden . Oliver . Seneviratne . Sonia I. . Sugiyama . Masahiro . van Aalst . Maarten . Bala . Govindasamy . Mach . Katharine J. . Ginzburg . Veronika . de Coninck . Heleen . Patt . Anthony . Cross-Working Group Box SRM: Solar Radiation Modification . Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change . 2021 . 2021 . 1238 . 10.1017/9781009157896.007. 2021AGUFM.U13B..05K .
127. Bond . T. C. . Bounding the role of black carbon in the climate system: A scientific assessment . 10.1002/jgrd.50171 . 118 . 11 . Journal of Geophysical Research: Atmospheres . 5380–5552. 2013 . 2013JGRD..118.5380B. free .
128. http://www.geologytimes.com/Research/1600_Eruption_Caused_Global_Disruption.asp "1600 Eruption Caused Global Disruption"
129. https://web.archive.org/web/20131219035432/http://www.nbcnews.com/id/24467948/ Andrea Thompson, "Volcano in 1600 caused global disruption"
130. http://www.sciencecentric.com/news/article.php?q=08042402 "The 1600 eruption of Huaynaputina in Peru caused global disruption"
131. McCormick . M. Patrick . Thomason . Larry W. . Trepte . Charles R. . Atmospheric effects of the Mt Pinatubo eruption . Nature . February 1995 . 373 . 6513 . 399–404 . 10.1038/373399a0 . 1995Natur.373..399M . 46437912 .
132. Stowe LL, Carey RM, Pellegrino PP . 1992 . Monitoring the Mt. Pinatubo aerosol layer with NOAA/11 AVHRR data . Geophysical Research Letters . 19 . 2. 159–162 . 10.1029/91GL02958 . 1992GeoRL..19..159S. Submitted manuscript .
133. Perkins . Sid . Earth Not So Hot Thanks to Volcanoes . Science . 4 March 2013 . 10.1126/article.26322 . 31 January 2024 .
134. Neely III RR, Toon OB, Solomon S, Vernier JP, Alvarez C, English JM, Rosenlof KH, Mills MJ, Bardeen CG, Daniel JS, Thayer JP . Recent anthropogenic increases in SO2 from Asia have minimal impact on stratospheric aerosol. Geophysical Research Letters. 40. 5. 999–1004. 10.1002/grl.50263. moderate volcanic eruptions, rather than anthropogenic influences, are the primary source of the observed increases in stratospheric aerosol.. 2013GeoRL..40..999N . 2013. 1721.1/85851. 54922537. free.
135. Chung CE, Ramanathan V . 2006 . Weakening of North Indian SST Gradients and the Monsoon Rainfall in India and the Sahel . Journal of Climate . 19 . 10. 2036–2045 . 10.1175/JCLI3820.1 . 2006JCli...19.2036C . 10435613 .
136. Web site: Pollutants and Their Effect on the Water and Radiation Budgets. https://web.archive.org/web/20081216221948/http://apollo.eas.gatech.edu/EAS6792/presentations/aerosol_effects.ppt. dead. 16 December 2008.
137. Web site: Australian rainfall and Asian aerosols. https://web.archive.org/web/20120616044758/http://www.csiro.au/files/files/pbg2.pdf. dead. 16 June 2012.
138. Region 4: Laboratory and Field Operations – PM 2.5 (2008).PM 2.5 Objectives and History. U.S. Environmental Protection Agency.
139. Balmes . John R. . Fine . Jonathan M. . Sheppard . Dean . Symptomatic Bronchoconstriction after Short-Term Inhalation of Sulfur Dioxide . American Review of Respiratory Disease . November 1987 . 136 . 5 . 1117–1121 . 10.1164/ajrccm/136.5.1117 . 3674573 .
140. Nieuwenhuijsen, M.J. (2003). Exposure Assessment in Occupational and Environmental Epidemiology. London: Oxford University Press.
141. News: Pollution Particles Lead to Higher Heart Attack Risk . Bloomberg L.P. . 17 January 2008 . dead . https://web.archive.org/web/20110629014447/http://www.bloomberg.com/apps/news?pid=washingtonstory&sid=aBt.yLf.YfOo . 29 June 2011 . The pollutants, abundant in urban areas, are less than 0.18 micrometers in size and cause four times more artery buildup than particles four times larger, said Jesus Araujo, director of environmental cardiology at University of California, Los Angeles..
142. Araujo . Jesus A. . etal . Ambient Particulate Pollutants in the Ultrafine Range Promote Early Atherosclerosis and Systemic Oxidative Stress . Circulation Research . January 17, 2008 . 102 . 5 . 589–596 . 10.1161/CIRCRESAHA.107.164970 . 18202315 . 3014059 .
143. Hennig . Frauke . Quass . Ulrich . Hellack . Bryan . Küpper . Miriam . Kuhlbusch . Thomas A. J. . Stafoggia . Massimo . Hoffmann . Barbara . February 2018 . Ultrafine and Fine Particle Number and Surface Area Concentrations and Daily Cause-Specific Mortality in the Ruhr Area, Germany, 2009–2014 . Environmental Health Perspectives . en . 126 . 2 . 027008 . 10.1289/EHP2054 . 0091-6765 . 6066351 . 29467106.
144. Ultrafine particles and PM in the air of cities around the world: Are they representative of each other?. 2019 . 10.1016/j.envint.2019.05.021 . De Jesus . Alma Lorelei . Rahman . Md Mahmudur . Mazaheri . Mandana . Thompson . Helen . Knibbs . Luke D. . Jeong . Cheol . Evans . Greg . Nei . Wei . Ding . Aijun . Qiao . Liping . Li . Li . Portin . Harri . Niemi . Jarkko V. . Timonen . Hilkka . Luoma . Krista . Petäjä . Tuukka . Kulmala . Markku . Kowalski . Michal . Peters . Annette . Cyrys . Josef . Ferrero . Luca . Manigrasso . Maurizio . Avino . Pasquale . Buonano . Giorgio . Reche . Cristina . Querol . Xavier . Beddows . David . Harrison . Roy M. . Sowlat . Mohammad H. . Sioutas . Constantinos . Environment International . 129 . 118–135 . 31125731 . 164216753 . 1 .
145. Lippmann, M., Cohen, B.S., Schlesinger, R.S. (2003). Environmental Health Science. New York: Oxford University Press.
146. Web site: Scattering Matrix for Typical Urban Anthropogenic Origin Cement Dust and Discrimination of Representative Atmospheric Particulates.
147. Web site: The dangers of a scrap yard fire in your community. 10 October 2022.
148. Web site: Cargo boat fire put out in Hong Kong's Victoria Harbour after burning for 15 hours and sending fumes across city. 3 June 2021.
149. Web site: Stench from burning metal-waste ship blows across HK.
150. Web site: Electric Arc Furnace (EAF) Slag. 3 June 2021 .
151. Use of hazardous electric arc furnace dust in the construction industry: A cleaner production approach. 2022 . 10.1016/j.jclepro.2022.134282 . Nair . Abhilash T. . Mathew . Aneesh . a r . Archana . Akbar . M Abdul . Journal of Cleaner Production . 377 . 134282 . 2022JCPro.37734282N . 252553231 .
152. Web site: Sustainability.
153. Web site: Hong Kong Housing Authority Sustainability Report 2012/13. https://web.archive.org/web/20230628093414/https://www.epd.gov.hk/epd/english/how_help/tools_epr/files/hd_er2012e.pdf . 28 June 2023 .
154. Web site: Hong Kong Housing Authority - Environmental Report 2020/21. https://web.archive.org/web/20230628093525/https://www.housingauthority.gov.hk/mini-site/haer2021/en/environmental-performance-planning.html . 28 June 2023 .
155. Web site: Cement industry news from Global Cement. https://web.archive.org/web/20221203120609/https://www.globalcement.com/news/itemlist/tag/Fake. 3 December 2022.
156. Web site: 黑水泥厂"围城" 打假队一年揪出13家 . City "besieged" with dishonest cement factories, anti-counterfeiting teams found 13 of them in one year . Chinese.
157. Web site: Growing Importance of Slag Cement in the Global Cement Industry. 6 July 2022.
158. Web site: 房市新制大調查 爐渣屋掰 2021年起禁用爐渣 . 10 December 2020 . A look into the property market new regulations. No more slag house. Slag will be banned from 2021 . Chinese.
159. Web site: 新版預售屋契約禁用「煉鋼爐碴」 建商違規將挨罰 . 8 May 2019 . The new version of the pre-sale house contract prohibits "steelmaking furnace slag" and builders will be fined for violations . Chinese.
160. Web site: Welding - Fumes And Gases, OSH Answers. 10 February 2023 .
161. Li Y, Chen J, Bu S, Wang S, Geng X, Guan G, Zhao Q, Ao L, Qu W, Zheng Y, Jin Y, Tang J . Blood lead levels and their associated risk factors in Chinese adults from 1980 to 2018 . Ecotoxicol Environ Saf . 218 . 112294 . May 2021 . 33984660 . 10.1016/j.ecoenv.2021.112294 . 2021EcoES.21812294L .
162. Han Z, Guo X, Zhang B, Liao J, Nie L . Blood lead levels of children in urban and suburban areas in China (1997-2015): Temporal and spatial variations and influencing factors . Sci Total Environ . 625 . 1659–1666 . June 2018 . 29996461 . 10.1016/j.scitotenv.2017.12.315 . 2018ScTEn.625.1659H . 51617692 .
163. Experimental study to quantify airborne particle deposition onto and resuspension from clothing using a fluorescent-tracking method. 2022 . 8620412 . Ren . J. . Tang . M. . Novoselac . A. . Building and Environment . 209 . 108580 . 10.1016/j.buildenv.2021.108580 . 34848915 . 2022BuEnv.20908580R .
164. Web site: 地盤工滿身泥衣鞋入茶餐廳 網民批成身水泥累慘清潔工：做死阿姐 . 香港01 . 20 Jul 2023 . zh . 14 Aug 2023.
165. The effects of particulate matter sources on daily mortality: a case-crossover study of Barcelona, Spain. 2011. 21846610. Ostro. B.. Tobias. A.. Querol. X.. Alastuey. A.. Amato. F.. Pey. J.. Pérez. N.. Sunyer. J.. Environmental Health Perspectives. 119. 12. 1781–1787. 10.1289/ehp.1103618. 3261985.
166. Web site: 10-year Hospital Development Plan.
167. Web site: Architectural Services Department - Capital Projects Under Construction.
168. Relation between PM pollution and Covid-19 mortality in Western Europe for the 2020–2022 period. 2022 . 9310379 . Renard . J. B. . Surcin . J. . Annesi-Maesano . I. . Delaunay . G. . Poincelet . E. . Dixsaut . G. . The Science of the Total Environment . 848 . 157579 . 10.1016/j.scitotenv.2022.157579 . 35901896 . 2022ScTEn.84857579R .
169. Assessing the impact of long-term exposure to nine outdoor air pollutants on COVID-19 spatial spread and related mortality in 107 Italian provinces. 2022 . 10.1038/s41598-022-17215-x . Perone . Gaetano . Scientific Reports . 12 . 1 . 13317 . 35922645 . 9349267 . 2022NatSR..1213317P .
170. 10.1038/s41370-021-00366-w. free. SARS-CoV-2 test positivity rate in Reno, Nevada: Association with PM during the 2020 wildfire smoke events in the western United States . 2021 . Kiser . Daniel . Elhanan . Gai . Metcalf . William J. . Schnieder . Brendan . Grzymski . Joseph J. . Journal of Exposure Science & Environmental Epidemiology . 31 . 5 . 797–803 . 34257389 . 8276229 .
171. 10.1038/s41598-021-85751-z . free. A global association between Covid-19 cases and airborne particulate matter at regional level . 2021 . Solimini . Angelo . Filipponi . F. . Fegatelli . D. Alunni . Caputo . B. . De Marco . C. M. . Spagnoli . A. . Vestri . A. R. . Scientific Reports . 11 . 1 . 6256 . 33737616 . 7973572 .
172. Web site: With metals and maybe even coronavirus, wildfire smoke is more dangerous than you think. . 22 July 2021 .
173. Web site: Silicosis, OSH Answers Fact Sheets. 13 June 2023.
174. Centers for Disease Control and Prevention. Preventing Silicosis and Deaths From Sandblasting. 1992. 10.26616/NIOSHPUB92102.
175. Flores-Pajot . Marie-Claire . Ofner . Marianna . Do . Minh T. . Lavigne . Eric . Villeneuve . Paul J. . Childhood autism spectrum disorders and exposure to nitrogen dioxide, and particulate matter air pollution: A review and meta-analysis . Environmental Research . November 2016 . 151 . 763–776 . 10.1016/j.envres.2016.07.030 . 27609410 . 2016ER....151..763F .
176. Chun . HeeKyoung . Leung . Cheryl . Wen . Shi Wu . McDonald . Judy . Shin . Hwashin H. . Maternal exposure to air pollution and risk of autism in children: A systematic review and meta-analysis . Environmental Pollution . January 2020 . 256 . 113307 . 10.1016/j.envpol.2019.113307 . 31733973 . free . 2020EPoll.25613307C .
177. Lam . Juleen . Sutton . Patrice . Kalkbrenner . Amy . Windham . Gayle . Halladay . Alycia . Koustas . Erica . Lawler . Cindy . Davidson . Lisette . Daniels . Natalyn . Newschaffer . Craig . Woodruff . Tracey . A Systematic Review and Meta-Analysis of Multiple Airborne Pollutants and Autism Spectrum Disorder . PLOS ONE . 21 September 2016 . 11 . 9 . e0161851 . 10.1371/journal.pone.0161851 . 27653281 . 5031428 . 2016PLoSO..1161851L . free .
178. Weisskopf . Marc G. . Kioumourtzoglou . Marianthi-Anna . Roberts . Andrea L. . Air Pollution and Autism Spectrum Disorders: Causal or Confounded? . Current Environmental Health Reports . December 2015 . 2 . 4 . 430–439 . 10.1007/s40572-015-0073-9 . 26399256 . 4737505 .
179. Fu . Pengfei . Yung . Ken Kin Lam . Air Pollution and Alzheimer's Disease: A Systematic Review and Meta-Analysis . Journal of Alzheimer's Disease . 15 September 2020 . 77 . 2 . 701–714 . 10.3233/JAD-200483 . 32741830 . 220942039 .
180. Tsai . Tsung-Lin . Lin . Yu-Ting . Hwang . Bing-Fang . Nakayama . Shoji F. . Tsai . Chon-Haw . Sun . Xian-Liang . Ma . Chaochen . Jung . Chau-Ren . Fine particulate matter is a potential determinant of Alzheimer's disease: A systemic review and meta-analysis . Environmental Research . October 2019 . 177 . 108638 . 10.1016/j.envres.2019.108638 . 31421449 . 2019ER....17708638T . 201057595 .
181. Braithwaite . Isobel . Zhang . Shuo . Kirkbride . James B. . Osborn . David P. J. . Hayes . Joseph F. . Air Pollution (Particulate Matter) Exposure and Associations with Depression, Anxiety, Bipolar, Psychosis and Suicide Risk: A Systematic Review and Meta-Analysis . Environmental Health Perspectives . December 2019 . 127 . 12 . 126002 . 10.1289/EHP4595 . 31850801 . 6957283 .
182. Lu . Jackson G . Air pollution: A systematic review of its psychological, economic, and social effects . Current Opinion in Psychology . April 2020 . 32 . 52–65 . 10.1016/j.copsyc.2019.06.024 . 31557706 . 199147061 .
183. Liu . Qisijing . Wang . Wanzhou . Gu . Xuelin . Deng . Furong . Wang . Xueqin . Lin . Hualiang . Guo . Xinbiao . Wu . Shaowei . Association between particulate matter air pollution and risk of depression and suicide: a systematic review and meta-analysis . Environmental Science and Pollution Research . February 2021 . 28 . 8 . 9029–9049 . 10.1007/s11356-021-12357-3 . 33481201 . 2021ESPR...28.9029L . 231677095 .
184. Schraufnagel . Dean E. . Balmes . John R. . Cowl . Clayton T. . De Matteis . Sara . Jung . Soon-Hee . Mortimer . Kevin . Perez-Padilla . Rogelio . Rice . Mary B. . Riojas-Rodriguez . Horacio . Sood . Akshay . Thurston . George D. . To . Teresa . Vanker . Anessa . Wuebbles . Donald J. . Air Pollution and Noncommunicable Diseases . Chest . February 2019 . 155 . 2 . 409–416 . 10.1016/j.chest.2018.10.042 . 30419235 . 6904855 .
185. News: Carrington . Damian . McMullan . Lydia . Blight . Garry . Roberts . Simon . Hulley-Jones . Frank . Revealed: air pollution may be damaging 'every organ in the body' . The Guardian . 17 May 2019 .
186. 6 . Raaschou-Nielsen . Ole . Andersen . Zorana J . Beelen . Rob . Samoli . Evangelia . Stafoggia . Massimo . Weinmayr . Gudrun . Hoffmann . Barbara . Fischer . Paul . Nieuwenhuijsen . Mark J . Brunekreef . Bert . Xun . Wei W . Katsouyanni . Klea . Dimakopoulou . Konstantina . Sommar . Johan . Forsberg . Bertil . Modig . Lars . Oudin . Anna . Oftedal . Bente . Schwarze . Per E . Nafstad . Per . De Faire . Ulf . Pedersen . Nancy L . Östenson . Claes-Göran . Fratiglioni . Laura . Penell . Johanna . Korek . Michal . Pershagen . Göran . Eriksen . Kirsten T . Sørensen . Mette . Tjønneland . Anne . Ellermann . Thomas . Eeftens . Marloes . Peeters . Petra H . Meliefste . Kees . Wang . Meng . Bueno-de-Mesquita . Bas . Key . Timothy J . de Hoogh . Kees . Concin . Hans . Nagel . Gabriele . Vilier . Alice . Grioni . Sara . Krogh . Vittorio . Tsai . Ming-Yi . Ricceri . Fulvio . Sacerdote . Carlotta . Galassi . Claudia . Migliore . Enrica . Ranzi . Andrea . Cesaroni . Giulia . Badaloni . Chiara . Forastiere . Francesco . Tamayo . Ibon . Amiano . Pilar . Dorronsoro . Miren . Trichopoulou . Antonia . Bamia . Christina . Vineis . Paolo . Hoek . Gerard . Air pollution and lung cancer incidence in 17 European cohorts: prospective analyses from the European Study of Cohorts for Air Pollution Effects (ESCAPE) . The Lancet Oncology . August 2013 . 14 . 9 . 813–822 . 10.1016/S1470-2045(13)70279-1 . 23849838 .
187. Cohen AJ, Ross Anderson H, Ostro B, Pandey KD, Krzyzanowski M, Künzli N, Gutschmidt K, Pope A, Romieu I, Samet JM, Smith K . 6 . The global burden of disease due to outdoor air pollution . Journal of Toxicology and Environmental Health. Part A . 68 . 13–14 . 1301–7 . 2005 . 16024504 . 10.1080/15287390590936166 . 2005JTEHA..68.1301C . 23814778 .
188. Web site: Air Pollution & Cardiovascular Disease . https://web.archive.org/web/20110514110919/http://www.niehs.nih.gov/health/impacts/cardiovascular/ . dead . 2011-05-14 . National Institute of Environmental Health Sciences.
189. Lave . Lester B.. Lester Lave. Seskin . Eugene P. . An Analysis of the Association between U.S. Mortality and Air Pollution . Journal of the American Statistical Association . June 1973 . 68 . 342 . 284–290 . 0162-1459 . 1537-274X . 10.1080/01621459.1973.10482421 .
190. Mokdad AH, Marks JS, Stroup DF, Gerberding JL . Actual causes of death in the United States, 2000 . JAMA . 291 . 10 . 1238–45 . March 2004 . 15010446 . 10.1001/jama.291.10.1238 . 14589790 .
191. Book: 10.2800/165 . 2009 . European Environment Agency . Spatial assessment of PM and ozone concentrations in Europe (2005) . Publications Office . 978-92-9167-988-1 .
192. Lim SS, Vos T, Flaxman AD, Danaei G, Shibuya K, Adair-Rohani H, Amann M, Anderson HR, Andrews KG, Aryee M, Atkinson C, Bacchus LJ, Bahalim AN, Balakrishnan K, Balmes J, Barker-Collo S, Baxter A, Bell ML, Blore JD, Blyth F, Bonner C, Borges G, Bourne R, Boussinesq M, Brauer M, Brooks P, Bruce NG, Brunekreef B, Bryan-Hancock C, Bucello C, Buchbinder R, Bull F, Burnett RT, Byers TE, Calabria B, Carapetis J, Carnahan E, Chafe Z, Charlson F, Chen H, Chen JS, Cheng AT, Child JC, Cohen A, Colson KE, Cowie BC, Darby S, Darling S, Davis A, Degenhardt L, Dentener F, Des Jarlais DC, Devries K, Dherani M, Ding EL, Dorsey ER, Driscoll T, Edmond K, Ali SE, Engell RE, Erwin PJ, Fahimi S, Falder G, Farzadfar F, Ferrari A, Finucane MM, Flaxman S, Fowkes FG, Freedman G, Freeman MK, Gakidou E, Ghosh S, Giovannucci E, Gmel G, Graham K, Grainger R, Grant B, Gunnell D, Gutierrez HR, Hall W, Hoek HW, Hogan A, Hosgood HD, Hoy D, Hu H, Hubbell BJ, Hutchings SJ, Ibeanusi SE, Jacklyn GL, Jasrasaria R, Jonas JB, Kan H, Kanis JA, Kassebaum N, Kawakami N, Khang YH, Khatibzadeh S, Khoo JP, Kok C, Laden F, Lalloo R, Lan Q, Lathlean T, Leasher JL, Leigh J, Li Y, Lin JK, Lipshultz SE, London S, Lozano R, Lu Y, Mak J, Malekzadeh R, Mallinger L, Marcenes W, March L, Marks R, Martin R, McGale P, McGrath J, Mehta S, Mensah GA, Merriman TR, Micha R, Michaud C, Mishra V, Mohd Hanafiah K, Mokdad AA, Morawska L, Mozaffarian D, Murphy T, Naghavi M, Neal B, Nelson PK, Nolla JM, Norman R, Olives C, Omer SB, Orchard J, Osborne R, Ostro B, Page A, Pandey KD, Parry CD, Passmore E, Patra J, Pearce N, Pelizzari PM, Petzold M, Phillips MR, Pope D, Pope CA, Powles J, Rao M, Razavi H, Rehfuess EA, Rehm JT, Ritz B, Rivara FP, Roberts T, Robinson C, Rodriguez-Portales JA, Romieu I, Room R, Rosenfeld LC, Roy A, Rushton L, Salomon JA, Sampson U, Sanchez-Riera L, Sanman E, Sapkota A, Seedat S, Shi P, Shield K, Shivakoti R, Singh GM, Sleet DA, Smith E, Smith KR, Stapelberg NJ, Steenland K, Stöckl H, Stovner LJ, Straif K, Straney L, Thurston GD, Tran JH, Van Dingenen R, van Donkelaar A, Veerman JL, Vijayakumar L, Weintraub R, Weissman MM, White RA, Whiteford H, Wiersma ST, Wilkinson JD, Williams HC, Williams W, Wilson N, Woolf AD, Yip P, Zielinski JM, Lopez AD, Murray CJ, Ezzati M, AlMazroa MA, Memish ZA . 6 . A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010 . Lancet . 380 . 9859 . 2224–60 . December 2012 . 23245609 . 4156511 . 10.1016/s0140-6736(12)61766-8 .
193. Web site: 2021-12-24 . Air pollution in Europe: These are the worst-hit cities to live in . 2022-04-01 . euronews . en.
194. Laden . F . Neas . L M . Dockery . D W . Schwartz . J . Association of fine particulate matter from different sources with daily mortality in six U.S. cities. . Environmental Health Perspectives . October 2000 . 108 . 10 . 941–947 . 10.1289/ehp.00108941 . 11049813 . 1240126 .
195. Ozkaynak . Haluk . Thurston . George D. . Associations Between 1980 U.S. Mortality Rates and Alternative Measures of Airborne Particle Concentration . Risk Analysis . December 1987 . 7 . 4 . 449–461 . 10.1111/j.1539-6924.1987.tb00482.x . 3444932 . 1987RiskA...7..449O .
196. Mailloux . Nicholas A. . Abel . David W. . Holloway . Tracey . Patz . Jonathan A. . Nationwide and Regional PM-Related Air Quality Health Benefits From the Removal of Energy-Related Emissions in the United States . GeoHealth . 6 . 5 . 16 May 2022 . e2022GH000603 . 10.1029/2022GH000603 . 35599962 . 9109601 . 2022GHeal...6..603M .
197. News: Carrington . Damian . Air pollution significantly raises risk of infertility, study finds . The Guardian . 17 February 2021 .
198. Zhang M, Mueller NT, Wang H, Hong X, Appel LJ, Wang X . Maternal Exposure to Ambient Particulate Matter ≤2.5 μm During Pregnancy and the Risk for High Blood Pressure in Childhood . Hypertension . 72 . 1 . 194–201 . July 2018 . 29760154 . 6002908 . 10.1161/HYPERTENSIONAHA.117.10944 .
199. Sapkota A, Chelikowsky AP, Nachman KE, Cohen AJ, Ritz B . 2012-12-01. Exposure to particulate matter and adverse birth outcomes: a comprehensive review and meta-analysis. Air Quality, Atmosphere & Health . 5. 4. 369–381. 10.1007/s11869-010-0106-3. 2012AQAH....5..369S . 95781433 .
200. Web site: 2009 Final Report: Integrated Science Assessment for Particulate Matter . US EPA National Center for Environmental Assessment, Research Triangle Park Nc, Environmental Media Assessment Group . Sacks J . 2017-03-31.
201. Erickson AC, Arbour L . The shared pathoetiological effects of particulate air pollution and the social environment on fetal-placental development . Journal of Environmental and Public Health . 2014 . 901017 . 2014-11-26 . 25574176 . 4276595 . 10.1155/2014/901017 . free .
202. Lee PC, Talbott EO, Roberts JM, Catov JM, Bilonick RA, Stone RA, Sharma RK, Ritz B . 6 . Ambient air pollution exposure and blood pressure changes during pregnancy . Environmental Research . 117 . 46–53 . August 2012 . 22835955 . 3656658 . 10.1016/j.envres.2012.05.011 . 2012ER....117...46L .
203. Woodruff TJ, Parker JD, Darrow LA, Slama R, Bell ML, Choi H, Glinianaia S, Hoggatt KJ, Karr CJ, Lobdell DT, Wilhelm M . 6 . Methodological issues in studies of air pollution and reproductive health . Environmental Research . 109 . 3 . 311–320 . April 2009 . 19215915 . 6615486 . 10.1016/j.envres.2008.12.012 . 2009ER....109..311W .
204. Byrne CD, Phillips DI . Fetal origins of adult disease: epidemiology and mechanisms . Journal of Clinical Pathology . 53 . 11 . 822–8 . November 2000 . 11127263 . 1731115 . 10.1136/jcp.53.11.822 .
205. Barker DJ . The fetal and infant origins of adult disease . BMJ . 301 . 6761 . 1111 . November 1990 . 2252919 . 1664286 . 10.1136/bmj.301.6761.1111 .
206. Pope CA, Burnett RT, Thun MJ, Calle EE, Krewski D, Ito K, Thurston GD . Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution . JAMA . 287 . 9 . 1132–41 . March 2002 . 11879110 . 4037163 . 10.1001/jama.287.9.1132 . C. Arden Pope .
207. http://www.medical-reference.net/2014/01/new-study-linked-pm-with-heart-attack.html EU's PM Limit Festering: New Study Linked PM with Heart Attack
208. Hussey SJ, Purves J, Allcock N, Fernandes VE, Monks PS, Ketley JM, Andrew PW, Morrissey JA . 6 . Air pollution alters Staphylococcus aureus and Streptococcus pneumoniae biofilms, antibiotic tolerance and colonisation . Environmental Microbiology . 19 . 5 . 1868–1880 . May 2017 . 28195384 . 6849702 . 10.1111/1462-2920.13686 . 2017EnvMi..19.1868H .
209. Web site: National Study Examines Health Risks of Coarse Particle Pollution. www.newswise.com.
210. Web site: Mongolia: Ulaanbaatar Air Pollution Linked to Public Health Crisis.
211. News: Matthews . Dylan . How humans could live two years longer . Vox . 27 December 2021 .
212. Web site: Symons . Angela . 2022-12-15 . Suicide rates rise as air quality worsens, study finds . 2022-12-19 . euronews . en.
213. Fan . Shu-Jun . Heinrich . Joachim . Bloom . Michael S. . Zhao . Tian-Yu . Shi . Tong-Xing . Feng . Wen-Ru . Sun . Yi . Shen . Ji-Chuan . Yang . Zhi-Cong . Yang . Bo-Yi . Dong . Guang-Hui . Ambient air pollution and depression: A systematic review with meta-analysis up to 2019 . Science of the Total Environment . January 2020 . 701 . 134721 . 10.1016/j.scitotenv.2019.134721 . 31715478 . 2020ScTEn.70134721F . 207944384 . 26 January 2022 . 31 March 2022 . https://web.archive.org/web/20220331123210/https://push-zb.helmholtz-muenchen.de/frontdoor.php?source_opus=57348 . dead .
214. Maher . Barbara A. . Ahmed . Imad A. M. . Karloukovski . Vassil . MacLaren . Donald A. . Foulds . Penelope G. . Allsop . David . Mann . David M. A. . Torres-Jardón . Ricardo . Calderon-Garciduenas . Lilian . Magnetite pollution nanoparticles in the human brain . Proceedings of the National Academy of Sciences . 27 September 2016 . 113 . 39 . 10797–10801 . 10.1073/pnas.1605941113 . 27601646 . 5047173 . 2016PNAS..11310797M . free .
215. Web site: Parkinson's Disease .
216. Olfactory cell cultures to investigate health effects of air pollution exposure: Implications for neurodegeneration. K. M.. Kanninen. R.. Lampinen. L. M.. Rantanen. L.. Odendaal. P.. Jalava. S.. Chew. A. R.. White. 1 June 2020. Neurochemistry International. 136. 104729. ScienceDirect. 10.1016/j.neuint.2020.104729. 32201281 . 214585295 .
217. Cohen AJ, Ross Anderson H, Ostro B, Pandey KD, Krzyzanowski M, Künzli N, Gutschmidt K, Pope A, Romieu I, Samet JM, Smith K . 6 . The global burden of disease due to outdoor air pollution . Journal of Toxicology and Environmental Health. Part A . 68 . 13–14 . 1301–7 . 2005 . 16024504 . 10.1080/15287390590936166 . 2005JTEHA..68.1301C . 23814778 .
218. Nawrot TS, Perez L, Künzli N, Munters E, Nemery B . Public health importance of triggers of myocardial infarction: a comparative risk assessment . Lancet . 377 . 9767 . 732–40 . February 2011 . 21353301 . 10.1016/S0140-6736(10)62296-9 . 20168936 . "Taking into account the OR and the prevalences of exposure, the highest PAF was estimated for traffic exposure (7.4%)... ":"... [O]dds ratios and frequencies of each trigger were used to compute population-attributable fractions (PAFs), which estimate the proportion of cases that could be avoided if a risk factor were removed. PAFs depend not only on the risk factor strength at the individual level but also on its frequency in the community. ... [T]he exposure prevalence for triggers in the relevant control time window ranged from 0.04% for cocaine use to 100% for air pollution. ... Taking into account the OR and the prevalences of exposure, the highest PAF was estimated for traffic exposure (7.4%) ...
219. Web site: Resources and Information.. https://web.archive.org/web/20081217174016/http://www.baq2008.org/system/files/sw16_Vajanapoom+presentation.pdf. dead. 17 December 2008. ww16.baq2008.org.
220. Smiley . Kevin T. . Racial and Environmental Inequalities in Spatial Patterns in Asthma Prevalence in the US South . Southeastern Geographer . 2019 . 59 . 4 . 389–402 . 10.1353/sgo.2019.0031 . . 210244838 .
221. Erratum: Eur. Phys. J. C.22, 695–705 (2002) – DOI 10.1007/s100520100827 Published online: 7 December 2001 . The European Physical Journal C . August 2002 . 24 . 4 . 665–666 . 10.1007/s10052-002-0987-x . 2002EPJC...24..665. . 195313204 .
222. Mikati . Ihab . Benson . Adam F. . Luben . Thomas J. . Sacks . Jason D. . Richmond-Bryant . Jennifer . Disparities in Distribution of Particulate Matter Emission Sources by Race and Poverty Status . American Journal of Public Health . 1 April 2018 . 108 . 4 . 480–485 . 10.2105/AJPH.2017.304297 . 29470121 . 5844406 .
223. Urban Air Pollution and Health Inequities: A Workshop Report . Environmental Health Perspectives . 1 June 2001 . 109 . s3 . 357–374 . 10.1289/ehp.01109s3357 .
224. News: Jervis . Rick . Gomez . Alan . Racism turned their neighborhood into 'Cancer Alley.' Now they're dying from COVID-19 . USA Today . 12 October 2020 .
225. Web site: US EPA. OAR. 2018-11-12. How Smoke from Fires Can Affect Your Health. 2020-11-26. US EPA .
226. Wegesser TC, Pinkerton KE, Last JA . California wildfires of 2008: coarse and fine particulate matter toxicity . Environmental Health Perspectives . 117 . 6 . 893–7 . June 2009 . 19590679 . 2702402 . 10.1289/ehp.0800166 .
227. Haikerwal A, Akram M, Del Monaco A, Smith K, Sim MR, Meyer M, Tonkin AM, Abramson MJ, Dennekamp M . 6 . Impact of Fine Particulate Matter (PM) Exposure During Wildfires on Cardiovascular Health Outcomes . Journal of the American Heart Association . 4 . 7 . e001653 . July 2015 . 26178402 . 4608063 . 10.1161/JAHA.114.001653 .
228. Reid CE, Considine EM, Watson GL, Telesca D, Pfister GG, Jerrett M . Associations between respiratory health and ozone and fine particulate matter during a wildfire event . Environment International . 129 . 291–298 . August 2019 . 31146163 . 10.1016/j.envint.2019.04.033 . free . 2019EnInt.129..291R .
229. Haikerwal A, Akram M, Sim MR, Meyer M, Abramson MJ, Dennekamp M . Fine particulate matter (PM) exposure during a prolonged wildfire period and emergency department visits for asthma . Respirology . 21 . 1 . 88–94 . January 2016 . 26346113 . 10.1111/resp.12613 . 22910313 . free .
230. DeFlorio-Barker S, Crooks J, Reyes J, Rappold AG . Cardiopulmonary Effects of Fine Particulate Matter Exposure among Older Adults, during Wildfire and Non-Wildfire Periods, in the United States 2008-2010 . Environmental Health Perspectives . 127 . 3 . 37006 . March 2019 . 30875246 . 6768318 . 10.1289/EHP3860 .
231. News: What is 'smoke brain'? How air pollution can harm our cognition and mental health. Toronto Star . June 27, 2023 . Kevin . Jiang .
232. The Guardian, 18 March 2021 "Oil Firms Knew Decades Ago Fossil Fuels Posed Grave Health Risks, Riles Reveal; Exclusive: Documents Seen by Guardian Show Companies Fought Clean-Air Rules Despite Being Aware of Harm Caused by Air Pollution"
233. The Guardian "75 Ways Trump Made America Dirtier and the Planet Warmer: In the Past Four Years, Trump has Shredded Environmental Protections for American Lands, Animals and People"
234. Union of Concerned Scientists, 27 April 2020 "Oil Industry Ghostwrites Trump's Deadly Anti-Environmental Policies"
235. Web site: Hogan CM . 2010. Abiotic factor. Encyclopedia of Earth. Emily Monosson and C. Cleveland. National Council for Science and the Environment.
236. Web site: US EPA . OAR . 26 April 2016 . Health and Environmental Effects of Particulate Matter (PM) . 5 October 2019 . US EPA.
237. Hamra GB, Guha N, Cohen A, Laden F, Raaschou-Nielsen O, Samet JM, Vineis P, Forastiere F, Saldiva P, Yorifuji T, Loomis D . 6 . Outdoor particulate matter exposure and lung cancer: a systematic review and meta-analysis . Environmental Health Perspectives . 122 . 9 . 906–11 . September 2014 . 24911630 . 4154221 . 10.1289/ehp.1408092 .
238. Web site: Department of the Environment . National Environment Protection (Ambient Air Quality) Measure . Federal Register of Legislation . 25 February 2016 . 16 November 2018.
239. Web site: Ambient air quality standards . 30 April 2013 . 30 April 2013 . https://web.archive.org/web/20130430003715/http://kjs.mep.gov.cn/hjbhbz/bzwb/dqhjbh/dqhjzlbz/201203/W020120410330232398521.pdf . live .
240. Web site: Air Quality Standards – Environment – European Commission . Ec.europa.eu . 1 February 2015.
241. Web site: Air Quality Objectives. Environmental Protection Department, Hong Kong. 19 December 2012. 27 July 2013.
242. Web site: 微小粒子状物質（PM）対策｜東京都環境局 大気・騒音・振動・悪臭対策 . Kankyo.metro.tokyo.jp . 1 February 2015 . https://web.archive.org/web/20150228230336/http://www.kankyo.metro.tokyo.jp/air/air_pollution/PM2.5/index.html . 28 February 2015 . dead.
243. Web site: Air Quality Standards .
244. Web site: Home . airkorea.or.kr.
245. Web site: 미세먼지 환경기준 선진국 수준 강화...'나쁨' 4배 늘 듯.
246. Web site: 細懸浮微粒管制. Environmental Protection Administration, ROC . 16 November 2015.
247. Web site: FEATURE: Air pollution reason for concern: groups - Taipei Times. 5 February 2014. www.taipeitimes.com.
248. Web site: Pm Naaqs Us Epa . Epa.gov . 1 February 2015.
249. Web site: WHO global air quality guidelines . WHO.
250. Web site: Canadian Ambient Air Quality Standards (CAAQS) for Fine Particulate Matter (PM) and Ozone. 11 December 2016. 20 December 2016. https://web.archive.org/web/20161220231843/http://www.ccme.ca/files/current_priorities/aqms_elements/caaqs_and_azmf.pdf. dead.
251. Web site: Burn better: Making changes for cleaner air.
252. Web site: Guidance for wood burning in London.
253. Web site: Log burners: What are the new rules and are they going to be banned?. Independent.co.uk. 6 February 2023.
254. Web site: Nanotechnology web page . Department of Toxic Substances Control . 2008 . dead . https://web.archive.org/web/20100101100532/http://www.dtsc.ca.gov/TechnologyDevelopment/Nanotechnology/index.cfm . 1 January 2010 .
255. Web site: Chemical Information Call-In web page . Department of Toxic Substances Control . 2008 . 28 December 2009 . https://web.archive.org/web/20100318011017/http://www.dtsc.ca.gov/PollutionPrevention/Chemical_Call_In.cfm . 18 March 2010 . dead .
256. Web site: Contact List for CNT January 22 & 26 2009 Document. 28 December 2009. https://web.archive.org/web/20170131163500/http://www.dtsc.ca.gov/TechnologyDevelopment/Nanotechnology/upload/AB289_CNT_Contact_List.pdf. 31 January 2017. dead.
257. Web site: Archived DTSC Nanotechnology Symposia . Department of Toxic Substances Control . dead . https://web.archive.org/web/20100101164727/http://www.dtsc.ca.gov/TechnologyDevelopment/Nanotechnology/ArchivedSymposium.cfm . 1 January 2010 .
258. http://www.dtsc.ca.gov/TechnologyDevelopment/Nanotechnology/index.cfm Chemical Information Call-in: Nanomaterials
259. Web site: Mapped: New Survey Shows Air Pollution Changes In Cities Around The World. Forbes.
260. News: Oliver Milman. Call for action on pollution as emissions linked to respiratory illnesses double. 3 April 2015. The Guardian. 1 April 2015. emissions of a key pollutant linked to respiratory illness have doubled over the past five years.
261. Li . Jie . Du . Huiyun . Wang . Zifa . Sun . Yele . Yang . Wenyi . Li . Jianjun . Tang . Xiao . Fu . Pingqing . 2017-04-01 . Rapid formation of a severe regional winter haze episode over a mega-city cluster on the North China Plain . Environmental Pollution . en . 223 . 605–615 . 10.1016/j.envpol.2017.01.063 . 28159396 . 2017EPoll.223..605L . 0269-7491.
262. Zhong . Junting . Zhang . Xiaoye . Gui . Ke . Liao . Jie . Fei . Ye . Jiang . Lipeng . Guo . Lifeng . Liu . Liangke . Che . Huizheng . Wang . Yaqiang . Wang . Deying . Zhou . Zijiang . 2022-07-12 . Reconstructing 6-hourly PM datasets from 1960 to 2020 in China . Earth System Science Data . English . 14 . 7 . 3197–3211 . 10.5194/essd-14-3197-2022 . 2022ESSD...14.3197Z . 250512127 . 1866-3508 . free .
263. Web site: China: annual PM levels Beijing 2022 . 2023-04-01 . Statista . en.
264. Web site: U.S. Consulate Air Quality Monitor and StateAir. https://web.archive.org/web/20110701120727/http://guangzhou.usembassy-china.org.cn/guangzhou-air-quality-monitor.html. dead. 2011-07-01. Consulate General of the United States of America Guangzhou, China. U.S. Department of State. n.d.. 24 December 2014.
265. Web site: Armed With NASA Data, South Korea Confronts Its Choking Smog. NPR.
266. Web site: China, South Korea build environment cooperation. 26 June 2018.
267. Web site: Air pollution chokes Thailand as campaigners call for stricter laws.
268. Web site: Air pollution hospitalises 200,000 in one week as fumes, emissions and smoke descend on Thailand. 13 March 2023.
269. Web site: Ambient (outdoor) air pollution. www.who.int.
270. Web site: Aviation Pollution.
271. Web site: Chapter 1 - Fly Ash - An Engineering Material - Fly Ash Facts for Highway Engineers - Recycling - Sustainability - Pavements - Federal Highway Administration. Federal Highway Administration (FHWA).
272. Web site: City Rankings, State of the Air, American Lung Association.
273. Web site: The Dirtiest And Cleanest Cities In America (The Worst Will Surprise You). Forbes.
274. Web site: An N95 Mask Is Your Best Defense Against Wildfire Smoke | Time . 7 June 2023 .
275. 17 September 2023 . Sulfur isotope-based source apportionment and control mechanisms of PM sulfate in Seoul, South Korea during winter and early spring (2017–2020) . Science of the Total Environment. 10.1016/j.scitotenv.2023.167112. Lee. Giyoon. Ahn. Jinho. Park. Seung-Myung. Moon. Jonghan. Park. Rokjin. Sim. Min Sub. Choi. Hanna. Park. Jinsoo. Ahn. Joon-Young. 905. 37717778. 262046328.