Genetic toxicology of folpet and captan

Abstract

Folpet and captan are fungicides whose genotoxicity depends on their chemical reaction with thiols. Multiple mutagenicity tests have been conducted on these compounds due to their positive activity in vitro and their association with gastrointestinal tumors in mice. A review of the collective data shows that these compounds have in vitro mutagenic activity but are not genotoxic in vivo. This dichotomy is primarily due to the rapid degradation of folpet and captan in the presence of thiol-rich matrices typically found in vivo. Genotoxicity has not been found in the duodenum, the mouse tumor target tissue. It is concluded that folpet like captan presents an unlikely risk of genotoxic effects in humans.

Keywords::

• Captan
• duodenum
• folpet
• genetic toxicology
• mutagenicity

Acknowledgements

We gratefully acknowledge the assistance of Cheryl Putnam with the preparation of the manuscript.

Declaration of interest

Makhteshim Agan of North America, Inc., a registrant of folpet and captan, employs Dr. Singh. Drs. Cohen, Gordon, and Arce have served as consultants for Makhteshim Agan of North America, Inc. The contents of this review reflect solely the view of the authors.

Notes

¹ The reported LD₅₀ (2850 mg/kg) from a local source was unusually low and mathematical errors were present that made data interpretation difficult.