Tyrone Hayes
Encyclopedia
Tyrone B. Hayes is a biologist
at University of California, Berkeley
. He is perhaps best known for his work on the effects of atrazine
on frogs, causing demasculinization in Northern Leopard Frog
s.
According to Hayes, "the induction of aromatase and estrogen production has been demonstrated ... in fish, frogs, alligators, birds, turtles, rats and human cells.", and further, "I believe that the preponderance of the evidence shows atrazine to be a risk to wildlife and humans. I would not want to be exposed to it, nor do I think it should be released into the environment." Syngenta has fought this research by quoting EPA findings regarding methodological problems in his research, which Hayes refutes. In 2007, the EPA's review of science literature concluded against claims made by Hayes and concluded its evaluation by stating: "At this time, EPA believes that no additional testing is warranted to address this issue."
by 15 water providers in Illinois seeking $350 million to clean drinking water of atrazine. A similar case involving six states is also occurring in federal court.
Biologist
A biologist is a scientist devoted to and producing results in biology through the study of life. Typically biologists study organisms and their relationship to their environment. Biologists involved in basic research attempt to discover underlying mechanisms that govern how organisms work...
at University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
. He is perhaps best known for his work on the effects of atrazine
Atrazine
Atrazine, 2-chloro-4--6--s-triazine, an organic compound consisting of an s-triazine-ring is a widely used herbicide. Its use is controversial due to widespread contamination in drinking water and its associations with birth defects and menstrual problems when consumed by humans at concentrations...
on frogs, causing demasculinization in Northern Leopard Frog
Northern Leopard Frog
The Northern Leopard Frog is a species of leopard frog from the true frog family, native to parts of Canada and United States. It is the state amphibian of Minnesota and Vermont.-Physical description:...
s.
Work on atrazine
In 2002, Nature published research by Hayes and colleagues showing that "developing male frogs exhibited female characteristics after exposure to atrazine ... at exposure levels deemed safe by the US Environmental Protection Agency (EPA).",. More recently, Hayes has been a co-author on work that details atrazine inducing mammary and prostate cancer in laboratory rodents and highlights atrazine as a potential cause of reproductive cancers in humans.According to Hayes, "the induction of aromatase and estrogen production has been demonstrated ... in fish, frogs, alligators, birds, turtles, rats and human cells.", and further, "I believe that the preponderance of the evidence shows atrazine to be a risk to wildlife and humans. I would not want to be exposed to it, nor do I think it should be released into the environment." Syngenta has fought this research by quoting EPA findings regarding methodological problems in his research, which Hayes refutes. In 2007, the EPA's review of science literature concluded against claims made by Hayes and concluded its evaluation by stating: "At this time, EPA believes that no additional testing is warranted to address this issue."
Class action lawsuit
Currently, the research that Hayes has published are being used as evidence in a class action lawsuit against SyngentaSyngenta
Syngenta AG is a large global Swiss agribusiness company which notably markets seeds and pesticides. Syngenta is involved in biotechnology and genomic research. The company is a leader in crop protection, and ranks third in total sales in the commercial agricultural seeds market. Sales in 2010 were...
by 15 water providers in Illinois seeking $350 million to clean drinking water of atrazine. A similar case involving six states is also occurring in federal court.