Tyrone Hayes. COURTESY OF TYRONE HAYES

Few academics can claim the notoriety of Dr. Tyrone Hayes, an endocrinologist at University of California, Berkeley. Hayes spoke at Victoria College last Monday, recounting a biotech company’s decade-long vendetta against his studies on the effects of a widely used herbicide.

Hayes’ ordeal began in 1997, when he was hired by a company now called Syngenta. When asked to study the effects of the herbicide atrazine on ecosystems, Hayes came upon some troubling evidence.

Allthough Hayes found a causal relationship between atrazine use and increased estrogen production in frogs, he says that Syngenta tried to suppress this conclusion. Endocrine disruption, an effect of atrazine that has also been noted in fish, birds, reptiles, and mammals — and which can cause a range of adverse impacts from infertility to cancer — wasn’t exactly the scientific result the company had sought from Hayes.

Hayes left Syngenta, but he didn’t stop studying atrazine. His first paper on the herbicide talked about the “chemical castration” of frogs, an incendiary term that critics have used against him.

“Chemical castration — the company hates that term,” says Hayes, grinning, “That’s why I put it in the title.”

His controlled study found that atrazine-treated male frogs could not produce enough testosterone to manufacture sperm or exhibit breeding behaviour. Consequently, out of all the mating incidences in the study, the atrazine-treated frogs failed to mate 85 per cent of the time.

Atrazine, Hayes found — in concentrations much lower than what is often measured in drinking water — stimulates the enzyme aromatase, which is responsible for turning testosterone into estrogen, causing hermaphroditism and birth defects in male frogs.

Hayes notes that, if atrazine works on aromatase in frogs, it likely does the same in humans.

“Our hormones are so close to frog hormones,” he says.

In female humans, the stimulation of aromatase is a notable cause of breast cancer. Hayes points out that Syngenta also manufactures a cancer drug, Letrozole, which blocks aromatase.

“That’s why I call [Syngenta] a ‘one-stop shop,’” says Hayes.

After Hayes stopped working for the company in 2000, Syngenta began a campaign to discredit him. The company actively pursued his downfall as a means of stopping his research against atrazine. Syngenta representatives followed Hayes to his lectures, tried to entice him to sue, and hired writers to publicly question Hayes’ methodology and character. He says that he and his family were explicitly threatened by the company.

“They say ‘it’s just some crazy guy at Berkeley and his frogs,’” he recalls, referring to accusations from Syngenta that his data on atrazine is irrelevant.

“I’m still crazy — the crazy part holds,” he continues. “But the science is not only good, it’s been replicated around the world.”

Hayes says that he told the US Environmental Protection Agency (EPA) about his findings, but they didn’t consider his evidence sufficient enough to ramp up regulations. The EPA considers the herbicide innocuous, despite data that say otherwise.

Chris Davison, a spokesperson for Syngenta Canada, called atrazine a “well-tested, safe, and beneficial product that is critical to agriculture.” Davison added that the weed-killer has “environmental and economic benefits” that are “well-documented.” 

Syngenta has written articles about the safety of atrazine as a public relations gesture to drive this point home, publishing the work in newspapers under the guise of independent authorship. 

Davison acknowledged in an email that “engaging experts to support [an organization’s] position” is “common practice.”

Hayes condemns practices like these for causing widespread bias in scientific research. He blames the “revolving door” phenomenon, a term referring to the tendency for corporate executives and government officials to swap positions, as a primary reason for the EPA’s reluctance to regulate atrazine. 

“The EPA’s evaluation of atrazine was conducted by this guy,” Hayes said, pointing to a photograph of Humboldt University endocrinologist Dr. Werner Kloas, “who works for Syngenta.” 

To release public policy from the grip of industrial interests, Hayes suggests that tax revenue from big business could fund independent research, helping scientific findings remain neutral. Currently, companies in the US fund their own research directly, and thus have ample opportunities to generate results that favour their products.

“I was taught that I should let the science speak for itself,” Hayes says. But when he realized that the EPA wasn’t listening, Hayes took it upon himself to speak for science.

“Those who have the privilege to know have the duty to act,” says Hayes, quoting Einstein. “We have an obligation, especially when the EPA is counting on us.”

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