Common weed killer gives male frogs sex change
Last Updated: Thursday, December 3, 2009 | 8:14 PM ET
CBC News
http://www.cbc.ca/canada/ottawa/story/2009/12/03/ottawa-frogs-sex-change-atrazine.htmlA popular weed killer sprayed on cornfields across North America turns male frogs into females even at low levels, Ottawa biologists have found.
Vance Trudeau, a University of Ottawa biologist, and his PhD student Valérie Langlois raised leopard frog tadpoles over a spring and summer in outdoor tanks containing the herbicide atrazine. The low levels of the herbicide were only 12.5 per cent higher (1.8 micrograms per litre) than the maximum levels (1.6 micrograms per litre) found in the Raisin River in Cornwall, Ont., where the tadpoles were captured.
The study, published in the Nov. 19 issue of the journal Environmental Health Perspectives, found that 20 per cent more frogs were female after being exposed to atrazine, compared with frogs that weren't exposed to the herbicide. In addition, many male frogs exposed to atrazine had formed egg cells in their testicles.
