Herbicides: Feminization of male frogs in the wild TYRONE HAYES, KELLY HASTON, MABLE TSUI, ANHTHU HOANG, CATHRYN HAEFFELE & AARON VONK Laboratory for Integrative Studies in Amphibian Biology, Museum of Vertebrate Zoology, and Department of Integrative Biology, University of California, Berkeley, California 94720-3140, USA e-mail: tyrone@socrates.berkeley.edu Atrazine is the most commonly used herbicide in the United States and probably in the world. Here we investigate the effects of exposure to water-borne atrazine contamination on wild leopard frogs (Rana pipiens) in different regions of the United States and find that 10–92% of males show gonadal abnormalities such as retarded development and hermaphroditism. These results are supported by laboratory observations, which together highlight concerns over the biological effects of environmental atrazine on amphibians. Nature 419, 895 - 896 (2002) Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.