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Delayed neurotoxicity of phenylphosphonothioate esters
Science (New York, N.Y.)
|August 17, 1979
Summary
Single oral doses of five phenylphosphonothioate esters caused delayed neurotoxicity in hens. This neurotoxicity, characterized by nerve degeneration, may be a common trait among these types of insecticides.
Area of Science:
- Toxicology
- Neuroscience
- Environmental Science
Background:
- Phenylphosphonothioate esters are a class of chemical compounds used in insecticides.
- Delayed neurotoxicity is a potential adverse effect of certain organophosphorus compounds.
- Understanding the neurotoxic potential of these insecticides is crucial for risk assessment.
Purpose of the Study:
- To investigate the delayed neurotoxic effects of single oral doses of five different phenylphosphonothioate esters in hens.
- To establish the relative potency of these compounds in inducing neurotoxicity.
- To determine if delayed neurotoxicity is a general characteristic of phenylphosphonothioate insecticides.
Main Methods:
- Administration of a single oral dose of five phenylphosphonothioate esters (cyanofenphos, EPN, desbromoleptophos, leptophos, and EPBP) to hens.
- Histological examination of spinal cord and peripheral nerves to assess axonal and myelin degeneration.
- Comparative analysis of neurotoxicity potency among the tested compounds.
Main Results:
- All five tested phenylphosphonothioate esters induced delayed neurotoxicity in hens.
- The potency of these compounds in causing neurotoxicity, in descending order, was cyanofenphos, EPN, desbromoleptophos, leptophos, and EPBP.
- Histological findings revealed marked axonal and myelin degeneration in the spinal cord and peripheral nerves of affected hens.
Conclusions:
- Delayed neurotoxicity is a potential and likely general feature of phenylphosphonothioate insecticides.
- The study highlights the neurotoxic risks associated with exposure to this class of insecticides.
- Further research may be warranted to explore the mechanisms and broader implications of this neurotoxicity.
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