Photo: Kochia, southwest Montana. © 2020 Delena Norris-Tull
Atrazine (one of the Triazines)
Summaries of the research and commentary by Dr. Delena Norris-Tull, Professor Emerita of Science Education, University of Montana Western, October 2020, updated November 2024.
In a 2018 visit to the NRCS Laramie County Field Office, Cheyenne Wyoming, I interviewed Jim Cochran, District Manager, and Jim Pike, District Conservationist. Jim Cochran told me, “Wyoming and Montana agencies are more reluctant to push the landowners than they used to be, because of the new concerns about herbicides.”
Jim Pike said, “We were bolder when we had less information about the chemicals we were using. Now we’re more reluctant to push landowners to control their weeds. Now it’s hard to find a well without atrazine. Atrazine was used a lot in this area in the 1970s.”
John Samson, from the Wyoming Department of Transportation, told me, “Kochia has become resistant to the triazines [a broad spectrum, Group 5 herbicide]. We used to use triazines but we no longer use them due to the damage they did to some crops on alkaline soils.
Atrazine was invented in 1958. It has been one of the most commonly used herbicides in the US and Australia for decades. It is used to treat broadleaf weeds in grass crops, such as corn and sugar cane. It is also used to treat weeds in lawns and in golf course greens.
In some areas of the US, atrazine has been found in drinking water at levels above what was considered safe. Studies have indicated it is an endocrine disrupter, and thus can alter the natural hormonal system. Sheley, et al., 2011, describe research that suggests that atrazine has played a role in “global declines in amphibian populations.”
The European Union banned atrazine in 2004. However, the US EPA has reviewed the research on the safety of atrazine several times since 2001, and has deemed it not to be a safety issue, with the current level of restrictions on its use. The US National Cancer Institute has also concluded that atrazine does not pose a cancer risk. The main company that produces it, Syngenta, settled a class action lawsuit in 2012 related to contaminated water supplies. The company did not admit any guilt. In surface water in a few watersheds in Missouri and Nebraska, atrazine remains at unacceptably high levels.
Within this website, refer to the section, Impacts on the Environment & Health, for research summaries on the toxic effects of atrazine on fish and amphibians.
Reference:
The following sections provide information on some of the most widely used modern herbicides:
Next Sections on Herbicides:
Atrazine (one of the Triazines)
Summaries of the research and commentary by Dr. Delena Norris-Tull, Professor Emerita of Science Education, University of Montana Western, October 2020, updated November 2024.
In a 2018 visit to the NRCS Laramie County Field Office, Cheyenne Wyoming, I interviewed Jim Cochran, District Manager, and Jim Pike, District Conservationist. Jim Cochran told me, “Wyoming and Montana agencies are more reluctant to push the landowners than they used to be, because of the new concerns about herbicides.”
Jim Pike said, “We were bolder when we had less information about the chemicals we were using. Now we’re more reluctant to push landowners to control their weeds. Now it’s hard to find a well without atrazine. Atrazine was used a lot in this area in the 1970s.”
John Samson, from the Wyoming Department of Transportation, told me, “Kochia has become resistant to the triazines [a broad spectrum, Group 5 herbicide]. We used to use triazines but we no longer use them due to the damage they did to some crops on alkaline soils.
Atrazine was invented in 1958. It has been one of the most commonly used herbicides in the US and Australia for decades. It is used to treat broadleaf weeds in grass crops, such as corn and sugar cane. It is also used to treat weeds in lawns and in golf course greens.
In some areas of the US, atrazine has been found in drinking water at levels above what was considered safe. Studies have indicated it is an endocrine disrupter, and thus can alter the natural hormonal system. Sheley, et al., 2011, describe research that suggests that atrazine has played a role in “global declines in amphibian populations.”
The European Union banned atrazine in 2004. However, the US EPA has reviewed the research on the safety of atrazine several times since 2001, and has deemed it not to be a safety issue, with the current level of restrictions on its use. The US National Cancer Institute has also concluded that atrazine does not pose a cancer risk. The main company that produces it, Syngenta, settled a class action lawsuit in 2012 related to contaminated water supplies. The company did not admit any guilt. In surface water in a few watersheds in Missouri and Nebraska, atrazine remains at unacceptably high levels.
Within this website, refer to the section, Impacts on the Environment & Health, for research summaries on the toxic effects of atrazine on fish and amphibians.
Reference:
- Sheley, R.L., James, J.J., Rinella, M. J., Blumenthal, D., & DiTomaso, J.M. (2011). Invasive plant management on anticipated conservation benefits: A scientific assessment. In D.D. Briske (Ed.) Conservation benefits of rangeland practices: Assessment, recommendation, and knowledge gaps. (pp. 293-336). USDA Natural Resources Conservation Service.
The following sections provide information on some of the most widely used modern herbicides:
Next Sections on Herbicides: