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Heptachlor induced changes in fenitrothion metabolism
M Mestitzova1, J Kovac, K Durcek
1Research Institute of Industrial Hygiene and Occupational Medicine, Institute of Hygiene, Bratislava, Czechoslovakia.
Bulletin of Environmental Contamination and Toxicology
|August 31, 2013
Summary
Heptachlor pretreatment significantly speeds up fenitrothion metabolism in rats. This pesticide exposure enhances the conversion of fenitrothion to its toxic oxon analogue in blood and liver tissues.
Area of Science:
- Environmental toxicology
- Pesticide metabolism
- Organophosphate insecticides
Background:
- Organophosphate pesticides like fenitrothion are widely used but can pose risks.
- Heptachlor is a persistent organochlorine pesticide.
- Understanding pesticide interactions is crucial for risk assessment.
Purpose of the Study:
- To investigate the effect of chronic heptachlor exposure on fenitrothion metabolism in rats.
- To determine if heptachlor alters the rate of fenitrothion conversion to its oxon analogue.
Main Methods:
- Rats were pretreated with heptachlor in their diet for three months.
- The metabolism of fenitrothion was studied using radiolabeled P-fenitrothion.
- Oxon analogue levels in blood and liver were compared between pretreated and control groups.
Main Results:
- Heptachlor pretreatment significantly increased the metabolism rate of fenitrothion.
- The conversion of fenitrothion to its oxon analogue was both enhanced and accelerated in pretreated rats.
- Elevated oxon analogue levels were observed in the blood and liver of rats exposed to heptachlor.
Conclusions:
- Chronic exposure to heptachlor can significantly alter the metabolic pathways of fenitrothion.
- Heptachlor pretreatment enhances and accelerates the bioactivation of fenitrothion to its toxic oxon form.
- This interaction may increase the toxicity of fenitrothion in environments with co-existing heptachlor contamination.
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