Pesticides

Used to get rid of pests of all kinds. If it is toxic to other life forms, it may be toxic to us. –Also may be toxic to other organism that we don’t want them to harm. Must be used with care –~20,000/year in US receive emergency medical care from perceived or actual exposure –~30/year die from above

Pesticides Most important are insecticides, herbicides, and fungicides Persistent pesticides remain in environment and spread. –Most recent research has been for short-lived pesticides –Most persistent ones have been removed from use. Like DDT

DDT Hailed as “miraculous” in 1945 by Sir Winston Churchill –Saved millions of lives Malaria – mosquitoes Yellow fever – mosquitoes Typhus – body lice Fleas – bubonic plague Banned in the late 1960’s in developed countries –Still being used in underdeveloped countries Still saving millions of lives/year – imported foods?

Organochlorine insecticides

Bioaccumulation + bioconcentration = biomagnification ppm in water More soluble in fats than in water

Organophosphate and Carbamate Insecticides Non-persistant – break down quickly in the environment. –Don’t bioaccumulate More immediately toxic to humans and mammals Examples: –Malathion – will soon be restricted –Diazinone – no longer available

Pyrethrin, an natural insecticide Most – unstable in sunlight

H23 – C , 29, 30, 63, 64, 66, 69, 70, 72, 87, 88