Induction of prophage lambda by chlorinated pesticides

Area of Science:

• Environmental Science
• Toxicology
• Genetics

Background:

• Chlorinated organic compounds are significant environmental carcinogens.
• Many are not detected as genotoxic by standard assays like the Salmonella assay.
• Rodent carcinogenicity data highlights the need for better detection methods.

Purpose of the Study:

• To evaluate the Microscreen phage-induction assay's sensitivity to chlorinated pesticides.
• To identify a short-term assay suitable for detecting genotoxic chlorinated carcinogens.
• To compare the Microscreen assay's performance with the Salmonella assay.

Main Methods:

• Utilized the Microscreen phage-induction assay with Escherichia coli.
• Tested ten chlorinated pesticides, including DDT, mirex, lindane, and toxaphene.
• Assessed prophage induction with and without metabolic activation (S9).

Main Results:

• Eight of ten tested pesticides induced prophage.
• The assay identified chlordane and lindane as genotoxic, unlike the Salmonella assay.
• Potency rankings were established for captan, dichlorvos, toxaphene, lindane, nitrofen, and chlordane.

Conclusions:

• The Microscreen phage-induction assay is a sensitive tool for detecting genotoxic chlorinated organics.
• It offers advantages over the Salmonella assay for certain environmental carcinogens.
• This assay aids in identifying environmental contaminants that pose genetic risks.