Controversial frog researcher Tyrone Hayes is the subject of a fifteen-minute documentary by the late Jonathan Demme. Part of a pilot series on Amazon called “The New Yorker Presents,” the short is available to stream for free. Dr. Hayes is an integrative biologist who made his name investigating the effects of the agrochemical atrazine, primarily used in cornfields, on frogs. The film, WHAT’S MOTIVATING HAYES, premiered in 2016. Atrazine use is currently under review by the Environmental Protection Agency, which is headed under the Trump Administration by Scott Pruitt.

Dr. Hayes–originally with funding from the chemical manufacturing company Syngenta–found in 2000 that the herbicide atrazine affects the sexual development of frogs; Syngenta, which makes atrazine, subsequently disputed Hayes’s findings and launched a campaign to discredit him. This was the subject of a 2014 New Yorker article by Rachel Aviv.


As estimated in 2014, over 60 million pounds of atrazine per year are used for agriculture in the United States. It is banned as a pesticide by the European Union. A preliminary ecological risk (not human health risk) assessment for the herbicide, submitted to the EPA in 2016, concluded that “there is potential chronic risk to fish, amphibians, and aquatic invertebrates […] risk concerns for mammals, birds, reptiles, plants and plant communities.” Atrazine runoff can leak into the water supply and when it is sprayed on crops it can evaporate into the air. “When you’re exposed to it developmentally, and you’re exposed to it over time, just like any other estrogenic chemical then you’re increasing your likelihood of getting for example, breast cancer or prostate cancer early in life,” Hayes says in the film.

Atrazine is being assessed for human health risk. At the federal level, three parts per billion (ppb) of atrazine is allowed in treated tap water. But in California, based on a 1999 study of increased breast cancer rates in rats with atrazine exposure, the legal maximum is set at one ppb. The EPA is due to make a decision about atrazine use in 2017.

WHAT’S MOTIVATING HAYES is produced by Alex Gibney’s company Jigsaw Productions in collaboration with Condé Nast Entertainment. Season One of “The New Yorker Presents” is available to stream on Amazon. Dr. Tyrone Hayes is a researcher at UC Berkeley. From August 4 through 24, a tribute series to director Jonathan Demme featuring THE SILENCE OF THE LAMBS, PHILADELPHIA, and a range of his other film work will be presented at BAM.