Major Pesticide Classes and Selected Examples

Pesticide ClassExamplesToxicityComment, Uses
OrganochlorinesDDT, endrin, aldrin, chlordane, lindane• High toxicity• Many organochlorines now banned in the United States
• Lindane has been banned in California, elsewhere used for control of lice and scabies
• DDT and other organochlorines have long metabolic disposition and are stored in fatty tissues and can persist in the environment
OrganophosphatesParathion, chlorpyrifos, dichlorvos, acephate, methyl-parathion, malathion, phorate• Most OPs are highly toxic• Parathion is banned for use in the United States
• Malathion is considered relatively less toxic than other OPs• Chlorpyrifos is no longer approved for residential use
• Most others are used for insect control in both agricultural and home settings
• Malathion is an approved treatment of head lice
N-Methyl carbamatesAldicarb, carbaryl, carbofuran, pirimicarb, propoxur• Aldicarb and carbaryl are both highly toxic• Insect control in agricultural and home settings
• Other carbamates have a relatively moderate toxicity
Pyrethrins and pyrethroidsPermethrin, cyano-pyrethroids: deltamethrin, cypermethrin, fenvalerate• Permethrin has relatively low toxicity• Permethrin is a common pediculicide
• Other pyrethroids have moderate toxicity• Most other pyrethroids are commonly used to control insects, often used in home and garden
NeonicotinoidsImidacloprid• Relatively newer class of insecticides• Selective affinity toward insect nicotinic acetylcholine receptors compared with mammalian nicotinic acetylcholine receptors
• Have relatively lower toxicity than OPs and carbamates• Often used as spot-on flea control for domestic animals
N-Phenylpyrazole insecticidesFipronil• Relatively newer class of insecticides• Often used as spot-on flea control for domestic animals
• Yard treatments for insect control
Phosphonate herbicidesGlyphosate• Because of primary mechanism of action, has relatively low toxicity from active ingredient.• Acts on plant cell wall
• Toxicity often due to the accompanying organic solvent• Commercially available in many products
Chlorophenoxy herbicides2,4-D, 2,4,5-T• Moderate toxicity• Weed control
Dipyridyl herbicidesParaquat, diquat• Highly toxic• Infrequently used
• Paraquat toxicity often requires lung transplant
Long-acting anticoagulantsBrodifacoum (superwarfarins)• Rodenticides
• Longer-acting than warfarin
• Recently eliminated packaging as loose pellets
  • 2,4,5-T, 2,4,5-trichlorophenoxy acetic acid.