Isopropalin is a herbicide. Introduced in 1969, it is a preëmergent selective dinitroaniline to control annual grasses and broadleaf weeds. Brought by DowElanco in 1972 to the US and Australia, it is now considered obsolete.[1] In 1974, American farmers used 250000lbs of isopropalin.[2]
Paarlan was a 69% isopropalin emulsifiable concentrate[3] approved for use on tobacco.[4] It required soil incorporation due to low solubility, ultraviolet light degradation and high volatilisation, and it may have been registered for white potatoes and tomatoes.[5] Dow marketed Paarlan to southern culture, with a video advert claiming it "is just as much a part of tobacco country as ham and biscuits are part of breakfast."[6]
Rats fed diets with large amounts of isopropalin had reduced hemoglobin concentrations, lowered hematocrits, and altered organ weights at the higher doses tested.[7]