Organophosphorous And Carbamates Insecticides
Organophosphor ous and
Carbamates
Insecticides
Reporters:
Bacanto, Kharen Mae B.
Mangga, Medelen V.
Paquit, Ruby F.
Organophosphorus insecticides • Organophosphorus insecticides are normally esters, amides, or thiol derivatives of phosphoric, phosphonic, phosphorothioic, or phosphonothioic acids. Most are only slightly soluble in water and have a high oil-to-water partition coefficient and low vapor pressure.
• Organophosphates
- are commonly used for small animals as flea and tick powders, sprays, foggers, shampoos and dips, flea collars, and formerly, as systemic insecticides.
• Examples: Malathion, dibrom, chlorpyrifos, temephos, diazinon and terbufos are organophosphates. Mode of Action
• Organophosphorus insecticides exert their acute effects in both insects and mammals by inhibiting acetylcholinesterase (AChE) in the nervous system with subsequent accumulation of toxic levels of acetylcholine
(ACh), which is a neurotransmitter. In many cases, the organophosphorylated enzyme is fairly stable, so that recovery from intoxication may be slow.
What is Acetylcholinesterase (
AChE)?
• An enzyme that breaks down the neurotransmitter acetylcholine at the synaptic clef (the space between two nerve cells) so the next nerve impulse can be transmitted across the synaptic gap.
Effects of Poisoning
• Chronic toxicity
• Repeated or prolonged exposure to organophosphates may result in the same effects as acute exposure including the delayed symptoms.
• Other effects repeatedly exposed include impaired memory and concentration, disorientation, severe depressions, irritability, confusion, headache, speech difficulties, delayed reaction times, nightmares, sleepwalking and drowsiness or insomnia.
• An influenza-like condition with headache, nausea, weakness, loss of appetite, and malaise.
• Low level exposure
• Even at relatively low levels organophosphates may be hazardous to human health. The pesticides act on a set of brain chemicals closely related to
those
Carbamates
Insecticides
Reporters:
Bacanto, Kharen Mae B.
Mangga, Medelen V.
Paquit, Ruby F.
Organophosphorus insecticides • Organophosphorus insecticides are normally esters, amides, or thiol derivatives of phosphoric, phosphonic, phosphorothioic, or phosphonothioic acids. Most are only slightly soluble in water and have a high oil-to-water partition coefficient and low vapor pressure.
• Organophosphates
- are commonly used for small animals as flea and tick powders, sprays, foggers, shampoos and dips, flea collars, and formerly, as systemic insecticides.
• Examples: Malathion, dibrom, chlorpyrifos, temephos, diazinon and terbufos are organophosphates. Mode of Action
• Organophosphorus insecticides exert their acute effects in both insects and mammals by inhibiting acetylcholinesterase (AChE) in the nervous system with subsequent accumulation of toxic levels of acetylcholine
(ACh), which is a neurotransmitter. In many cases, the organophosphorylated enzyme is fairly stable, so that recovery from intoxication may be slow.
What is Acetylcholinesterase (
AChE)?
• An enzyme that breaks down the neurotransmitter acetylcholine at the synaptic clef (the space between two nerve cells) so the next nerve impulse can be transmitted across the synaptic gap.
Effects of Poisoning
• Chronic toxicity
• Repeated or prolonged exposure to organophosphates may result in the same effects as acute exposure including the delayed symptoms.
• Other effects repeatedly exposed include impaired memory and concentration, disorientation, severe depressions, irritability, confusion, headache, speech difficulties, delayed reaction times, nightmares, sleepwalking and drowsiness or insomnia.
• An influenza-like condition with headache, nausea, weakness, loss of appetite, and malaise.
• Low level exposure
• Even at relatively low levels organophosphates may be hazardous to human health. The pesticides act on a set of brain chemicals closely related to
those