Atrazine is the second most commonly used herbicide in the United States. Tyrone B. Hayes, an American biologist and professor of Integrative Biology at University of California, has warned about atrazine for years, purporting the herbicide is responsible for feminizing amphibians. Syngenta, manufacturers of Atrazine, ran a smear campaign against Hayes, attempting to discredit his reputation. Recently, the Environmental Protection Agency (EPA) released a 500-page draft report on the environmental reverberations of atrazine, vindicating Hayes’s research.
“Anyone who cares about wildlife, people and the environment should be deeply troubled by this finding,” said Nathan Donley, a scientist with the Center for Biological Diversity. “When the government’s own scientists say there’s enough atrazine in streams and rivers right now to kill frogs and other imperiled wildlife, we should be worried. How many animals have to die before we do what Europe did 12 years ago and ban atrazine?”
This isn’t the first time the EPA has reviewed atrazine but it is the first time the agency deemed the herbicide as a risk to birds, mammals, frogs and plants it was not intended to destroy. Since the chemical was first reviewed in 2003, a body of evidence has surfaced demonstrating that atrazine is now widespread in the environment and could endanger plants and wildlife.
At the forefront of this research is Tyron Hayse, who has been publishing studies on the adverse effects of atrazine for years. He has argued the chemical acts as an endocrine disruptor, which hinders the sexual development of amphibians, such as frogs. After his first study of atrazine was published, which was originally funded by Syngenta, Hayes said the company launched a campaign against him, trying to destroy his professional reputation.
“I’ve known all along that atrazine posed a risk to wildlife,” Hayes told Take Part. “I worked with these guys, I sat in a room with these guys, and they acknowledged that atrazine is bad. My science, my students—the work that we did was so solid that they had to go after me with personal attacks.”
The report, published Thursday by the EPA concluded, “This risk assessment concludes that aquatic plant communities are impacted in many areas where atrazine use is heaviest, and there is potential chronic risk to fish, amphibians, and aquatic invertebrates in these same locations.” What is ironic is that the EPA cited the work of Hayes, along with other researchers, about the impact atrazine can have on the sexual development of amphibians, including producing “gonadal malformations” that Hayes documented.
The demise of herbicides
It is not known what will be done in the wake of the assessment. Atrazine was first approved in 1958 but has provoked concerns about its environmental impact for years. As a result, the herbicide has been banned from Europe. The long-term adverse health effects of the herbicide include reproductive, developmental and hormonal problems.
In response to a draft of the report, Timothy Pastoor, a toxicologist and former principal scientist at Syngenta, said in an email to Take Part that Syngenta, “continues to support and defend the use of this important herbicide. Atrazine has been the backbone of corn weed control in the U.S. for more than 50 years. Extensive scientific research and numerous regulatory reviews have continuously proven the benefits and safety of this active ingredient.”