Atrazine herbicide causes prostate inflammation in male rats and delays puberty

Aug 24, 2010

A new study shows that male rats prenatally exposed to low doses of atrazine, a widely used herbicide, are more likely to develop prostate inflammation and to go through puberty later than non-exposed animals. The research adds to a growing body of literature on atrazine, an herbicide predominantly used to control weeds and grasses in crops such as corn and sugar cane. Atrazine and its byproducts are known to be relatively persistent in the environment, potentially finding their way into water supplies.

The research, which is available online and will be featured on the cover of Reproductive Toxicology (Volume 30, Issue 4), found that the incidence of prostate inflammation went from 48 percent in the control group to 81 percent in the male offspring who were exposed to a mixture of atrazine and its breakdown products prenatally. The severity of the inflammation increased with the strength of the doses. Puberty was also delayed in the animals who received atrazine.

The doses of atrazine mixture given to the rats during the last five days of their pregnancy are close to the regulated levels in drinking water sources. The current maximum contamination level of atrazine allowed in drinking water is 3 parts per billion. The doses given to the animals were 0.09 (or 2.5 parts per million), 0.87, or 8.73 milligrams per kilogram body weight.

The research was led by Suzanne Fenton, Ph.D., and Jason Stanko, Ph.D., of the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health. Fenton began the work as a researcher at the United States (EPA), but completed the research at NIEHS, working closely with NIEHS pathologists. Both NIEHS and EPA provided financial support for the study.

"We didn't expect to see these kinds of effects at such low levels," Fenton said. She adds that this is the second paper to show low dose effects of atrazine metabolite mixtures. Fenton was the senior author on a 2007 paper which demonstrated low doses of the atrazine mix delayed mammary development in female siblings from the same litters used in this current study.

"It was noteworthy that the prostate inflammation decreased over time, suggesting the effects may not be permanent," said David Malarkey, D.V.M., Ph.D., an NIEHS pathologist and co-author on the paper.

Fenton points out that these findings may extend beyond atrazine alone, and may be relevant to other herbicides found in the same chlorotriazine family, including propazine and simazine. All three of the herbicides create the same set of breakdown products.

Fenton says more research is needed to understand the mechanism of action of the chlorotriazines and their metabolites on mammary and prostate tissue. "These tissues seem to be particularly sensitive to the effects of atrazine and its breakdown products," Fenton added. "The effects may be due to the stage of fetal development at the time the animals were exposed."

"We hope that this information will be useful to the EPA, as it completes its risk assessment of atrazine," said Linda Birnbaum, Ph.D., director of NIEHS and the National Toxicology Program.

Fenton will be presenting her research findings in September to the EPA, as part of its reassessment of atrazine. EPA announced in 2009 that it had begun a comprehensive new evaluation of atrazine to determine its effects on humans. At the end of this process, the agency will decide whether to revise its current risk assessment of atrazine and whether new restrictions are necessary to better protect public health.

Explore further: Noise from fireworks threatens young ears

More information: For more information about the EPA risk assessment, please visit http://www.epa.gov/pesticides/reregistration/atrazine/atrazine_update.htm.

Related Stories

Low-cost fibers remove trace atrazine from drinking water

Aug 23, 2004

A new generation of high surface-area porous materials for removing atrazine from water supplies has been developed by researchers at the University of Illinois at Urbana-Champaign. The low-cost and wear-resistant fibers ...

Pesticide atrazine can turn male frogs into females

Mar 01, 2010

Atrazine, one of the world's most widely used pesticides, wreaks havoc with the sex lives of adult male frogs, emasculating three-quarters of them and turning one in 10 into females, according to a new study by University ...

Recommended for you

Noise from fireworks threatens young ears

Jul 03, 2015

(HealthDay)—The Fourth of July weekend is a time for celebrations and beautiful fireworks displays. But, parents do need to take steps to protect their children's ears from loud fireworks, a hearing expert ...

Many new teen drivers 'crash' in simulated driving task

Jul 03, 2015

(HealthDay)—Around four in 10 newly licensed teen drivers "crashed" in a simulated driving test, suggesting that many adolescents lack the skills they need to stay safe on the road, according to a new study.

Insurer Aetna to buy Humana in $35B deal

Jul 03, 2015

Aetna will spend about $35 billion to buy rival Humana and become the latest health insurer bulking up on government business as the industry adjusts to the federal health care overhaul.

Feeling impulsive or frustrated? Take a nap

Jul 03, 2015

Taking a nap may be an effective strategy to counteract impulsive behavior and to boost tolerance for frustration, according to a University of Michigan study.

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

Caliban
1 / 5 (1) Aug 24, 2010
I don't believe it!
You mean to tell me that a widely-used agricultural poison poses a threat to animal life?
Get outta town!!!!

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.