Chlorethoxyfos

Chlorethoxyfos (O,O-diethyl-O-(1,2,2,2-tetrachloroethyl)phosphorothioate) is an organophosphate acetylcholinesterase inhibitor used as an insecticide. It is registered for the control of corn rootworms, wireworms, cutworms, seed corn maggot, white grubs and symphylans on corn. The insecticide is sold under the trade name Fortress by E.I. du Pont de Nemours & Company.- Nausea- Diarrhoea Chlorethoxyfos (O,O-diethyl-O-(1,2,2,2-tetrachloroethyl)phosphorothioate) is an organophosphate acetylcholinesterase inhibitor used as an insecticide. It is registered for the control of corn rootworms, wireworms, cutworms, seed corn maggot, white grubs and symphylans on corn. The insecticide is sold under the trade name Fortress by E.I. du Pont de Nemours & Company. Annual domestic usage of chlorethoxyfos is estimated to range from 8,500 to 17,800 pounds of active ingredient for approximately 37,000 to 122,000 acres treated. Approximately 1% of all corn acreage is treated. Chlorethoxyfos has a O-alkyl phosphorothioate type of phosphorus group which makes it similar to compounds such as chlorpyriphos-methyl, coumaphos, diazinon, dichlofenthion, fenitrothion, fenthion, parathion, parathion-methyl, pyrazophos, pyrimiphos-methyl, sulfotep, temephos, and thionazin. The compound does not have EU regulatory approval for use as an insecticide as it can be harmful for the aquatic environment and is deemed very toxic for humans. Chlorethoxyfos was first registered in the United States in 1995 to use as an insecticide. It was registered only conditionally by the United States Environmental Protection Agency since additional studies were needed to refine the risk assessments of the Agency. The Agency decided to reassess chlorethoxyfos tolerance and to conduct an occupational risk assessment as a condition of registration of the compound. In 1999, the Agency published the revised risk assessment which forms the basis of the decisions on risk management for chlorethoxyfos. The primary target of organophosphorus insecticides, like chlorethoxyfos, in both insects and mammals is the nervous system, by inhibiting acetylcholinesterase (AChE). The function of acetylcholinesterase is to break down the neurotransmitter acetylcholine which is released at cholinergic nerve endings in response to nervous stimuli. Organophosphorus compounds inhibit acetylcholinesterase by forming a covalent bond between the compound and the active site of AChE. By inhibiting acetylcholinesterase, acetylcholine accumulates in the synaptic cleft, reaching toxic levels. Loss of AChE activity leads to excessive nervous stimulation, which results in neuromuscular paralysis and may even cause respiratory failure. The organophosphorus compound is really stable and hydrolysis from the active site is very slow, leading to long-term toxic effects.