Atrazine and glyphosate in the hot seat

Sep 23, 2011

The environmental group Save the Frogs has successfully convinced the Environmental Protection Agency (EPA) to reconsider its policy on atrazine, also known as Atrex, despite the mandatory scheduled review that is supposed to take place in 2013.

Atrazine has been vital to the farm economy for more than 50 years and has been instrumental in increasing corn, sorghum and sugar-cane production. According to EPA, farming without atrazine would cost corn growers as much as $28 per acre in alternative herbicide costs and reduced yields. The total negative impact on corn, sorghum and sugar-cane for growers in the U.S. would exceed $2 billion if atrazine were not available, according to Syngenta Corp., the original producer of the product.

The Save the Frogs petition includes over 10,000 signatures, select statements from the public, and two brief summaries of published literature, one by Dr. Jason Rohr and one by Dr. Tyrone Hayes that is co-authored by 39 other scientists, according to the Federal Register.

In conjunction with the Save the Frog petition, EPA received nearly 50,000 emails from supporters of the Center for Biological Diversity and the Natural Resources Defense Council requesting that EPA “immediately take steps to phase out atrazine use in the United States.”

The group, along with Hayes, a professor at the University of California- Berkeley, claims that atrazine affects the sexual development of frogs. But EPA and independent researchers have rejected their claims in the past.

Hayes is well known to EPA scientists who reviewed four of his studies during EPA’s 2002 and 2003 examination of atrazine and found these studies and others he conducted to be too flawed and inconsistent to be considered, according to Anne E.

Lindsay, who was deputy director of the EPA’s Office of Pesticide Programs at the time.

Hayes participated in another study released in a March 2010 report, and EPA will likely take his work into consideration again during the upcoming atrazine review. But questions continue popping up relating to his studies. For example, Yale University Professor David Skelly, who was appointed by EPA to serve on a reviewing panel for Hayes’ latest study, has questioned whether or not the findings can be repeated in a natural habitat.

The Triazine Network, made up of farmers and farming groups, sent a letter, cosigned by over 120 groups, to EPA. In it, it claims the unscheduled and rushed re-review departs from the normal regulatory process. “Pesticides like atrazine are subject to regular review. In fact, atrazine was re-registered in 2006 and not scheduled for re-review until 2013. In October 2009, EPA scheduled an unprec edented

four Scientific Advisory Panels (SAPs) within 11 months. Since 2000, EPA reviews have included more than 16 opportunities for public comment, including six SAP meetings convened under the Federal Insecticide, Fungicide and Rodenticide Act,” according to the Triazine Network.

In a status update in April of 2010, EPA wrote: EPA concluded in 2007 that atrazine does not adversely affect amphibian gonadal development based on a review of laboratory and field studies, including studies submitted by the registrant and studies published in the scientific literature. At this time, EPA believes that no additional testing is warranted to address this issue.

According to Ann Bryan, senior manager of external communications at Syngenta, atrazine passes the most stringent, up-to-date safety requirements in the world.

According to Bryan, atrazine’s safety has been established in more than 6,000 scientific studies over the past 50 years. One example was a large-scale, two-country study audited by EPA, using 3,200 frogs that showed atrazine had no effect on growth, development, survival or sexual differentiation.

Federal Registercomments must be received on or before Nov. 14, 2011. Glyphosate Along with atrazine coming under fire, glyphosate is also being scrutinized by EPA.

Researchers from the U.S. Geological Survey (USGS) report they have found significant levels of glyphosate, commonly known as Roundup, in air and water samples taken in Mississippi and Iowa.

What effects, if any, its presence could have on streams is unknown, but EPA is currently reviewing the registration for glyphosate and the latest findings by USGS likely will figure into that review. USDA has submitted the data it gathered in Mississippi and Iowa to EPA.

Glyphosate appears in streams throughout the growing season in Iowa and Mississippi, but is generally not observed during other times of the year. The study hints at the possibility of glyphosate polluting the water through other means than runoff.

In the recent studies, glyphosate was detected in surface waters, rain and air in areas where it is heavily used in the basin. Research on the transport of glyphosate was conducted as part of the USGS National Water-Quality Assessment program.

“Though glyphosate is the most widely used herbicide in the world, we know very little about its long term effects to the environment,” says Paul Capel, USGS chemist and an author on this study.

Glyphosate is far from a newcomer to controversy. First registered for use in the U.S. in 1974, the Monsanto Corporation’s herbicide has been a “frequent flyer” for the media. Most recently, a retired plant

pathologist from Purdue University launched a war against glyphosate with his claim that it is the cause of higher levels of certain plant diseases, animal diseases, human diseases, and decreased mineral nutrition in plants. His colleagues quickly distanced themselves. “In our opinion, the doomsday scenario painted by [Capel] is greatly exaggerated,” the Purdue Extension Weed Science department commented in their April 9, 2010, newsletter.

All pesticides sold or distributed in the U.S. must be registered with EPA. Glyphosate was re-registered in September 1993 after an EPA review concluding that its use in accordance with label directions would “not pose unreasonable risks or adverse effects to humans or the environment,” according to Monsanto.— Traci Eatherton, WLJ Editor