Pesticide Atrazine can turn male frogs into females

An atrazine-induced female frog (a genetic male) is shown (bottom) copulating with an unexposed male sibling. This union produced viable eggs and larvae that survived to metamorphosis and adulthood. Yet, because both animals were genetic males, the offspring were all males. (Tyrone Hayes photo)Atrazine, one of the world's most widely used pesticides, wreaks havoc with the sex lives of adult male frogs, emasculating three-quarters of them and turning one in 10 into females, according to a new study by University of California, Berkeley, biologists.

The 75 per cent that are chemically castrated are essentially "dead" because of their inability to reproduce in the wild, reports UC Berkeley's Tyrone B. Hayes, professor of integrative biology.