Pesticide biotransformations

Schlenk D (2005) Pesticide biotransformation in fish. In Mommsen TP, Moon TW (eds) Environmental toxicology, biochemistry and molecular biology of fishes, Chap 6, vol 6. Elsevier, San Diego, pp 171-190... 

V. Environmental factors that affect pesticide biotransformation... 

There are numerous chemicals utilized as pesticides around the world. However, few have been evaluated for the potential of biotransformation in fish. Several reviews of pesticide biotransformation in fish have been previously published16,39,60. 

Metals have been shown to dramatically alter CYP concentrations, but there have not been any studies examining the effects on pesticide biotransformation. In contrast, several studies have examined the effects of enzyme induction on pesticide biotransformation. Pre-exposure of channel catfish to the PCB mixture Aroclor 1254 failed to alter the biotransformation of chlorpyrifos or parathion81. As mentioned above, the fungicide propioconizole induced the activation of parathion to the oxon in fathead minnow53. 

Pesticide metabolism studies are, without question, very important components in the evaluation of the toxicological significance of pesticides to man. The rate, extent, mechanisms, and products of metabolism are inevitably linked to the expression of toxic action, and a clear definition of pesticide biotransformation is often a necessary prerequisite to understanding mechanisms of toxicity and to the formulation of approaches for assessment and management of potentially undesired toxic effects. 

Shaner, D. L., Tede, B. Designing Herbicide Tolerance Based on Metabolic Alteration The Challenges and the Future, in Pesticide Biotransformation in Plants and Microorganisms, Hall, J. C., Hoagland, R. E., Zablotowicz, R. M. (Eds.) ACS Symposium Series 777, American Chemical Society, Washington, DC, 2001. 

This review will focus on similarities and differences of pesticide metabolism by plants and prokaryotic organisms. Examples of pesticide biotransformations will be used to illustrate how these metabolic processes can affect efficacy, environmental fate, and persistence. 

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