Longstanding debate about farmers’ use of atrazine in Wisconsin       

By: Dana Singer

WISCONSIN — Thousands of acres of land in the United States are used by farmers who follow regulations to sustain safe and efficient methods for crop growth. The efficiency and cost-effective method of using atrazine, an herbicide that prevents weed growth, has subsequently affected human health through drinking water contamination found in family water wells. Despite the federal and state restrictions in place for Wisconsin-native farmers who use atrazine, it continues to be the most frequently used and the most commonly detected herbicide in Wisconsin groundwater today.

Atrazine contamination in drinking water wells is mainly caused by runoff herbicide use on row crops. High enough levels of consumption can lead to adverse human health effects, which include reproductive and cardiovascular problems. Since human health risks persist, contaminated wells must be replaced, but not all wells are eligible for well replacement grants from the Department of Natural Resources (DNR) in Wisconsin. These grants are used to cover the finances of families using wells as their primary source of water.

“In the last 10 years, we have given Well Compensation grants to replace ten private water supply wells that were atrazine impacted,” Martin Nessman, Private Water Section Field Supervisor and Program Manager for the State of Wisconsin Well Compensation Program said. “This only represents wells that were impacted above a health standard where the well owner was financially eligible for a grant.”

Christopher Gellasch, Groundwater Testing

Groundwater Testing Performed by UW Madison Geology Department.

“I had my wells checked and replaced in 2008. Our township had a program where we could have all of our wells tested,” Diane Tomlinson, well owner from Poynette, Wisconsin said. “We had all three of the offered tests performed, and atrazine was found in our water supply.”

Data from DNR’s Atrazine Replacement history indicates that from 1990-2010, 33 wells were replaced in Wisconsin due to atrazine contamination. According to DNR standards, in order to be financially eligible, a person must own a contaminated private water supply that serves a residence or is used for watering livestock. This provides 75 percent eligibility costs up to a maximum grant of $9,000.

“The contamination came from groundwater runoff from another farm, but yes we were eligible for a grant because we use our water for residential purposes,” Tomlinson said.

This leads to the question of how farmers prepare for this issue and what measures the state and federal government have taken to prevent atrazine contamination. According to the Environmental Protection Agency (EPA), atrazine has been placed under government restriction since 1974 after Congress passed the Safe Drinking Water Act (SDWA).

Lake Mendota

Lake Mendota in Madison, WI.

“There’s two governments involved here – one is the federal government, which monitors the labels that tell where you can use it, when you can use it and how much you can use.” Rick Graham of Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP) said. “The state of Wisconsin has kind of modified the federal label for atrazine and then further restricted its use because we did find it in a lot of private drinking water wells.”

According to the DATCP, Atrazine use in Wisconsin has declined and farmers have followed regulations due to the 1985 placement of the “Atrazine Rule” that enforced even further limitations on atrazine use as well as set atrazine prohibition in specific areas of Wisconsin.

Graham said that in his experience he has seen fewer issues with finding farmers who do not follow laws in place by the EPA and the DATCP.

“Since we had our wells replaced, they have established atrazine free zones around us so we haven’t had any more problems,” Tomlinson said. “Our first well was 76 ft. deep and our new one is 200 ft. deep so atrazine is no longer a problem even though there are still other chemicals out there.”

On the other hand, the many studies conducted to prove adverse human health effects of atrazine has encouraged farmers to veer away from pesticide and herbicide use altogether.

Warren Porter – Environmental Toxicologist, Researcher and Zoology Professor at UW Madison.

UW Madison Zoology Professor

Warren Porter – Environmental Toxicologist, Researcher and Zoology Professor at UW Madison.

“Well for one, the EPA is extremely flawed,” Environmental Toxicologist Warren Porter said. “And from my research we found that atrazine reduces fertility in males from the groundwater they consume and suppresses immune functions and hormone levels as well. As long as present trends continue I do believe it could have generational effects, which isn’t a risk farmers should be willing to take.”

From his study, “Endocrine, Immune and Behavioral Effects of Aldibard, Atrazine and Nitrate Mixtures at Groundwater Concentrations,” Porter and his associates conclude that atrazine-contaminated groundwater aids in the altering of gene expression affecting sexual development, reproductive function and muscle function.

“Specific human health concerns should be closely monitored if current trends in pesticide use continue,” Porter said.

Although other methods do exist to serve the same function as atrazine, Wisconsin farmers still choose this as their primary method of weed elimination.

“Atrazine is very much more familiar. Since it’s been around since the 50s some of the growers out there, their fathers and possibly even grandfathers were using it, so they seem to understand the product; they’re comfortable with it,” Graham said. “There’s a comfort level there. Also it is a little bit cheaper. But there are certainly other alternatives.”

According to Graham, since the state of Wisconsin decided to establish atrazine prohibition areas where use of atrazine is completely prohibited, it is essential that farmers in these areas step away from their “comfort” zones and seek different methods to eliminate weed growth.

Paul D. Mitchell - Co-Director of UW Extension’s Nutrient and Pest Management Program (NPM) and Associate Professor in the Department of Agriculture and Applied Economics at UW Madison.

Paul D. Mitchell – Co-Director of UW Extension’s Nutrient and Pest Management Program (NPM) and Associate Professor in the Department of Agriculture and Applied Economics at UW Madison.

According to a report by Paul D. Mitchell, Co-Director of UW Extension’s Nutrient and Pest Management Program (NPM) and Associate Professor in the Department of Agriculture and Applied Economics at UW Madison, “[in order to] to counter the problem, government programs or extension services need to educate farmers to utilize more non-herbicide weed management tools, such as higher crop seed rates, using cover crops and precision fertilizer management and diverse crop rotations.”

In his research, Mitchell references the longstanding debate over whether atrazine should be banned completely, as it is in Europe, due to the local and national concerns about water contamination and possible cancer risk in humans as well as its toxic effect on freshwater invertebrates.

Mitchell’s study concludes that agricultural sustainability can only be achieved if there is diversity in both agro ecosystem and in the herbicide and non-herbicide tools used in weed control.

Even though restrictions and prohibitions have been placed on use of atrazine, it is still the most commonly detected herbicide in Wisconsin groundwater today, and it is unclear what the future holds and how the herbicide will further play a role in water contamination and its risk on both human health and environmental harm.

“I’m just glad that our well was accounted for, and hopefully atrazine free zones will turn Wisconsin into an atrazine free state!” Tomlinson said.