Toxin Explained
A toxin is a naturally occurring poison produced by metabolic activities of living cells or organisms.[1] They occur especially as proteins, often conjugated. The term was first used by organic chemist Ludwig Brieger (1849–1919)[2] and is derived from the word "toxic".
Toxins can be small molecules, peptides, or proteins that are capable of causing disease on contact with or absorption by body tissues interacting with biological macromolecules such as enzymes or cellular receptors. They vary greatly in their toxicity, ranging from usually minor (such as a bee sting) to potentially fatal even at extremely low doses (such as botulinum toxin).[3] [4]
Terminology
Toxins are often distinguished from other chemical agents strictly based on their biological origin.[5]
Less strict understandings embrace naturally occurring inorganic toxins, such as arsenic.[6] [7] [8] Other understandings embrace synthetic analogs of naturally occurring organic poisons as toxins,[9] and may[10] or may not[11] embrace naturally occurring inorganic poisons. It is important to confirm usage if a common understanding is critical.
Toxins are a subset of toxicants. The term toxicant is preferred when the poison is man-made and therefore artificial.[12] The human and scientific genetic assembly of a natural-based toxin should be considered a toxin as it is identical to its natural counterpart.[13] The debate is one of linguistic semantics.
The word toxin does not specify method of delivery (as opposed to venom, a toxin delivered via a bite, sting, etc.). Poison is a related but broader term that encompasses both toxins and toxicants; poisons may enter the body through any means - typically inhalation, ingestion, or skin absorption. Toxin, toxicant, and poison are often used interchangeably despite these subtle differences in definition. The term toxungen has also been proposed to refer to toxins that are delivered onto the body surface of another organism without an accompanying wound.[14]
A rather informal terminology of individual toxins relates them to the anatomical location where their effects are most notable:
On a broader scale, toxins may be classified as either exotoxins, excreted by an organism, or endotoxins, which are released mainly when bacteria are lysed.
Biological
The term "biotoxin" is sometimes used to explicitly confirm the biological origin as opposed to environmental or anthropogenic origins.[15] Biotoxins can be classified by their mechanism of delivery as poisons (passively transferred via ingestion, inhalation, or absorption across the skin), toxungens (actively transferred to the target's surface by spitting, spraying, or smearing), or venoms (delivered through a wound generated by a bite, sting, or other such action).[14] They can also be classified by their source, such as fungal biotoxins, microbial toxins, plant biotoxins, or animal biotoxins.[16]
Toxins produced by microorganisms are important virulence determinants responsible for microbial pathogenicity and/or evasion of the host immune response.[17]
Biotoxins vary greatly in purpose and mechanism, and can be highly complex (the venom of the cone snail can contain over 100 unique peptides, which target specific nerve channels or receptors).[18]
Biotoxins in nature have two primary functions:
- Predation, such as in the spider, snake, scorpion, jellyfish, and wasp
- Defense as in the bee, ant, termite, honey bee, wasp, poison dart frog and plants producing toxins
- The toxins used as defense in species among the poison dart frog can also be used for medicinal purposes
Some of the more well known types of biotoxins include:
- Cyanotoxins, produced by cyanobacteria
- Dinotoxins, produced by dinoflagellates
- Necrotoxins cause necrosis (i.e., death) in the cells they encounter.[19] Necrotoxins spread through the bloodstream. In humans, skin and muscle tissues are most sensitive to necrotoxins. Organisms that possess necrotoxins include:
- Neurotoxins primarily affect the nervous systems of animals. The group neurotoxins generally consists of ion channel toxins that disrupt ion channel conductance. Organisms that possess neurotoxins include:
- Myotoxins are small, basic peptides found in snake and lizard venoms, They cause muscle tissue damage by a non-enzymatic receptor based mechanism. Organisms that possess myotoxins include:
- Cytotoxins are toxic at the level of individual cells, either in a non-specific fashion or only in certain types of living cells:
Weaponry
Many living organisms employ toxins offensively or defensively. A relatively small number of toxins are known to have the potential to cause widespread sickness or casualties. They are often inexpensive and easily available, and in some cases it is possible to refine them outside the laboratory.[20] As biotoxins act quickly, and are highly toxic even at low doses, they can be more efficient than chemical agents. Due to these factors, it is vital to raise awareness of the clinical symptoms of biotoxin poisoning, and to develop effective countermeasures including rapid investigation, response, and treatment.[21] [22]
Environmental
See also: Environmental toxicology. The term "environmental toxin" can sometimes explicitly include synthetic contaminants[23] such as industrial pollutants and other artificially made toxic substances. As this contradicts most formal definitions of the term "toxin", it is important to confirm what the researcher means when encountering the term outside of microbiological contexts.
Environmental toxins from food chains that may be dangerous to human health include:
Research
In general, when scientists determine the amount of a substance that may be hazardous for humans, animals and/or the environment they determine the amount of the substance likely to trigger effects and if possible establish a safe level. In Europe, the European Food Safety Authority produced risk assessments for more than 4,000 substances in over 1,600 scientific opinions and they provide open access summaries of human health, animal health and ecological hazard assessments in their OpenFoodTox[34] database.[35] [36] The OpenFoodTox database can be used to screen potential new foods for toxicity.[37]
The Toxicology and Environmental Health Information Program (TEHIP)[38] at the United States National Library of Medicine (NLM) maintains a comprehensive toxicology and environmental health web site that includes access to toxins-related resources produced by TEHIP and by other government agencies and organizations.[39] This web site includes links to databases, bibliographies, tutorials, and other scientific and consumer-oriented resources. TEHIP also is responsible for the Toxicology Data Network (TOXNET),[40] an integrated system of toxicology and environmental health databases that are available free of charge on the web.
TOXMAP is a Geographic Information System (GIS) that is part of TOXNET.[41] TOXMAP uses maps of the United States to help users visually explore data from the United States Environmental Protection Agency's (EPA) Toxics Release Inventory and Superfund Basic Research Programs.
See also
External links
Notes and References
- Web site: toxin – Definition from the Merriam-Webster Online Dictionary . 13 December 2008.
- Book: Brade, Helmut. Endotoxin in Health and Disease. 1999. CRC Press. 41299257. 9780824719449.
- Book: Gupta, PK. Illustrated Toxicology with Study Questions. 2018. Elsevier Inc.. 978-0-12-813213-5.
- Web site: 2021-06-01 . Diagnosis and Treatment Botulism . 2022-04-12 . CDC . en-us . live . https://web.archive.org/web/20220412162744/https://www.cdc.gov/botulism/testing-treatment.html . 2022-04-12 .
- Are Some Fungal Volatile Organic Compounds (VOCs) Mycotoxins?. Joan W . Bennett. Arati A . Inamdar . Toxins . Basel . 2015 . 7. 9 . 3785–3804 . 10.3390/toxins7093785 . free . 26402705 . 4591661 .
- Web site: Arsenic in Food: FAQ . Brenda . Goodman . WebMD . 20 May 2022.
- Web site: Arsenic in your food - Our findings show a real need for federal standards for this toxin . Consumer Reports. 2012 .
- Keeping arsenic out of rice . Carolyn . Beans . Proceedings of the National Academy of Sciences . 2021 . 118 . 33 . 10.1073/pnas.2113071118. 34380741 . 8379988 . 2021PNAS..11813071B . 236989837 . free .
- Web site: U.S. Code . 20 May 2022. the term "toxin" means the toxic material or product of plants, animals, microorganisms ...or a recombinant or synthesized molecule....
- Web site: Module 1: Introduction to Toxicology . Agency for Toxic Substances and Disease Registry . 20 May 2022. arsenic, a toxic metal, may occur as a natural contaminant ... or ... as a by-product of industrial activities. If the second case is true, such toxic substances are referred to as toxicants, rather than toxins..
- Web site: The Biological Weapons Convention – An overview . 30 June 1997. 20 May 2022 . Jozef . Goldblat . "The Convention applies to all natural or artificially created toxins, "whatever their origin or method of production" (Article I). It thus covers toxins produced biologically, as well as those produced by chemical synthesis".
- Web site: Difference Between Toxin and Toxicant (With Table). 31 October 2021.
- Genetic assembly and selective toxicity of diphtheria-toxin-related polypeptide hormone fusion proteins . 1987. 2847744. Murphy. J. R.. Bishai. W.. Williams. D.. Bacha. P.. Borowski. M.. Parker. K.. Boyd. J.. Waters. C.. Strom. T. B.. Biochemical Society Symposium. 53. 9–23.
- 10.1111/brv.12062 . Poisons, toxungens, and venoms: Redefining and classifying toxic biological secretions and the organisms that employ them . 2014 . Nelsen . David R. . Nisani . Zia . Cooper . Allen M. . Fox . Gerad A. . Gren . Eric C. K. . Corbit . Aaron G. . Hayes . William K. . Biological Reviews . 89 . 2 . 450–465 . 24102715 . 207101679 .
- Web site: biotoxin – Definition from the Merriam-Webster Online Dictionary . 13 December 2008.
- Web site: Biotoxins: What are Biotoxins? . 2023-07-06 . www.biosciences-labs.bham.ac.uk.
- Book: Proft T . 2009 . Microbial Toxins: Current Research and Future Trends . Caister Academic Press . 978-1-904455-44-8.
- Robinson . Samuel D . Norton . Raymond S . Conotoxin Gene Superfamilies . Marine Drugs . 12 . 12 . 6058–6101 . 17 December 2014 . 10.3390/md12126058 . 25522317 . 4278219. free .
- Book: . 2012 . Saunders/Elsevier . Philadelphia, PA . 978-1-4160-6257-8 . 1236 . 32nd.
- Janik . Edyta . Ceremuga . Michal . Saluk-Bijak . Joanna . Bijak . Michal . 2019-03-08 . Biological Toxins as the Potential Tools for Bioterrorism . International Journal of Molecular Sciences . 20 . 5 . 1181 . 10.3390/ijms20051181 . 1422-0067 . 6429496 . 30857127. free .
- Web site: Editorial . Team . Toxins: Venom within Living Cells or Organisms . 2021-07-17 . Unrevealed Files . 24 May 2021 . en-US.
- Płusa. Tadeusz. September 2015. [Toxins as a biological weapon]]. Polski Merkuriusz Lekarski. 39. 231. 131–133. 1426-9686. 26449572.
- Grigg J . Environmental toxins; their impact on children's health . Archives of Disease in Childhood . 89 . 3 . 244–50 . March 2004 . 14977703 . 1719840 . 10.1136/adc.2002.022202 .
- Vale C, Alfonso A, Vieytes MR, Romarís XM, Arévalo F, Botana AM, Botana LM . In vitro and in vivo evaluation of paralytic shellfish poisoning toxin potency and the influence of the pH of extraction . Analytical Chemistry . 80 . 5 . 1770–6 . March 2008 . 18232710 . 10.1021/ac7022266 .
- Oikawa H, Fujita T, Saito K, Satomi M, Yano Y. Difference in the level of paralytic shellfish poisoning toxin accumulation between the crabs Telmessus acutidens and Charybdis japonica collected in Onahama, Fukushima Prefecture . Fisheries Science . 73 . 2 . 395–403 . 2008 . 10.1111/j.1444-2906.2007.01347.x. 22926782 .
- Abouabdellah R, Taleb H, Bennouna A, Erler K, Chafik A, Moukrim A . Paralytic shellfish poisoning toxin profile of mussels Perna perna from southern Atlantic coasts of Morocco . Toxicon . 51 . 5 . 780–6 . April 2008 . 18237757 . 10.1016/j.toxicon.2007.12.004 .
- Wang L, Liang XF, Zhang WB, Mai KS, Huang Y, Shen D . Amnesic shellfish poisoning toxin stimulates the transcription of CYP1A possibly through AHR and ARNT in the liver of red sea bream Pagrus major . Marine Pollution Bulletin . 58 . 11 . 1643–8 . November 2009 . 19665739 . 10.1016/j.marpolbul.2009.07.004 . 2009MarPB..58.1643W .
- Wang L, Vaquero E, Leão JM, Gogo-Martínez A, Rodríguez Vázquez JA . Optimization of conditions for the liquid chromatographic-electrospray lonization-mass spectrometric analysis of amnesic shellfish poisoning toxins . . 53 . 1 . S231–35 . 2001 . 10.1007/BF02490333. 97937094 .
- Mouratidou T, Kaniou-Grigoriadou I, Samara C, Kouimtzis T . Detection of the marine toxin okadaic acid in mussels during a diarrhetic shellfish poisoning (DSP) episode in Thermaikos Gulf, Greece, using biological, chemical and immunological methods . The Science of the Total Environment . 366 . 2–3 . 894–904 . August 2006 . 16815531 . 10.1016/j.scitotenv.2005.03.002 . 2006ScTEn.366..894M .
- Doucet E, Ross NN, Quilliam MA . Enzymatic hydrolysis of esterified diarrhetic shellfish poisoning toxins and pectenotoxins . Analytical and Bioanalytical Chemistry . 389 . 1 . 335–42 . September 2007 . 17661021 . 10.1007/s00216-007-1489-3 . 21971745 .
- Poli MA, Musser SM, Dickey RW, Eilers PP, Hall S . Neurotoxic shellfish poisoning and brevetoxin metabolites: a case study from Florida . Toxicon . 38 . 7 . 981–93 . July 2000 . 10728835 . 10.1016/S0041-0101(99)00191-9 .
- Morohashi A, Satake M, Murata K, Naoki H, Kaspar HF, Yasumoto T. Brevetoxin B3, a new brevetoxin nalog isolated from the greenshell mussel perna canaliculus involved in neurotoxic shellfish poisoning in new zealand . . 36 . 49 . 8995–98 . 1995 . 10.1016/0040-4039(95)01969-O.
- Morohashi A, Satake M, Naoki H, Kaspar HF, Oshima Y, Yasumoto T . Brevetoxin B4 isolated from greenshell mussels Perna canaliculus, the major toxin involved in neurotoxic shellfish poisoning in New Zealand . Natural Toxins . 7 . 2 . 45–8 . 1999 . 10495465 . 10.1002/(SICI)1522-7189(199903/04)7:2<45::AID-NT34>3.0.CO;2-H .
- Web site: Chemical hazards data - OpenFoodTox. European Food Safety Authority. en. 2019-10-27.
- Dorne JL, Richardson J, Kass G, Georgiadis N, Monguidi M, Pasinato L, Cappe S, Verhagen H, Robinson T . OpenFoodTox: EFSA's open source toxicological database on chemical hazards in food and feed. . EFSA Journal . January 2017 . 15 . 1 . e15011 . 10.2903/j.efsa.2017.e15011 . 32625280 . 7009813 . free .
- Reilly L, Serafimova R, Partosch F, Gundert-Remy U, Cortiñas Abrahantes J, Dorne JM, Kass GE . Testing the thresholds of toxicological concern values using a new database for food-related substances . Toxicology Letters . 314 . 117–123 . October 2019 . 31325634 . 10.1016/j.toxlet.2019.07.019 . free .
- Pearce JM, Khaksari M, Denkenberger D . Preliminary Automated Determination of Edibility of Alternative Foods: Non-Targeted Screening for Toxins in Red Maple Leaf Concentrate . Plants . 8 . 5 . 110 . April 2019 . 31027336 . 6571818 . 10.3390/plants8050110 . free .
- Web site: Environmental Health and Toxicology Information. National Library of Medicine. 29 September 2010. 1 September 2018. https://web.archive.org/web/20180901172235/https://sis.nlm.nih.gov/enviro.html. dead.
- Fonger GC, Stroup D, Thomas PL, Wexler P . TOXNET: A computerized collection of toxicological and environmental health information . Toxicology and Industrial Health . 16 . 1 . 4–6 . January 2000 . 10798381 . 10.1177/074823370001600101 . 34029729 .
- Web site: TOXNET . toxnet.nlm.nih.gov . 29 September 2010 . https://web.archive.org/web/20190514171418/https://toxnet.nlm.nih.gov/ . 14 May 2019 . dead .
- Hochstein C, Szczur M . TOXMAP: a GIS-based gateway to environmental health resources . Medical Reference Services Quarterly . 25 . 3 . 13–31 . 2006-07-24 . 16893844 . 2703818 . 10.1300/J115v25n03_02 .