The Minnesota House Agriculture Committee rejected three bills that would have banned or restricted use of the farm herbicide atrazine, reported Minnesota Public Radio on March 17. The news was met with a collective sigh of relief by many Minnesota farmers, who rely on atrazine as one of their main cornfield herbicides to kill weeds.
Atrazine, in use in the U.S. for about five decades, is inexpensive and very effective in relatively small amounts. One of the bills would have banned atrazine in certain parts of the state as early as next year and would have phased out the herbicide completely, statewide, by 2008.
Proponents of the anti-atrazine bills had argued traces of the pesticide found in state drinking water may cause sexual deformities in frogs and could pose a cancer risk to humans. The anti-atrazine bills failed, opponents said, because the science behind such claims is highly controversial and has yet to gain credibility.
Science Debunks Atrazine Fears
In 2002, University of California-Berkeley researcher Tyrone Hayes claimed exposure to very low levels of atrazine can disrupt hormones and cause aberrant sexual development in male African clawed frogs. Hayes followed that with a study finding atrazine appears to make leopard frogs–the most common native American frog–hermaphrodites in the wild.
While studies conducted by the U.S. Environmental Protection Agency (EPA) in 2003 also found that atrazine leads to sexual deformities in frogs, EPA currently says atrazine is safe and has questioned Hayes’ findings.
Steven Milloy, publisher of the environmental Web site junkscience.com, recently reported the flaws of the sexual deformities claims. Explained Milloy, “EPA staff prepared a ‘White Paper on Potential Developmental Effects of Atrazine on Amphibians,’ concluding in bureaucrat-ese that the Hayes-induced panic is unfounded: ‘the available data do not establish a concordance of information to indicate that atrazine will or will not cause adverse developmental effects in amphibians.'”
In November 2002, recalled Milloy, Hayes published more laboratory results claiming low concentrations of atrazine were linked to frog deformities.
“But Hayes’ results were contradicted by a basic law of toxicology: The higher the dose, the greater the rate or severity of toxic effects,” noted Milloy. “Hayes reported that frogs exposed to 0.1 ppb (part per billion) of atrazine had triple the deformities of frogs exposed to 25 ppb of atrazine. The EPA states in its White Paper: ‘[Hayes’] data did not show a clear dose-response relationship.'”
Milloy continued, “Summarizing Hayes’ and other atrazine studies, the EPA states: ‘none of the laboratory studies fully accounted for environmental and animal husbandry factors capable of influencing endpoints which the studies were attempting to measure. … [P]oor water quality (e.g., low dissolved oxygen, high ammonia) could have created environmental conditions unfavorable to optimum survival, growth and development.'”
Atrazine Levels Low
The February 21 St. Paul Pioneer Press reported Minnesota’s agriculture department found small amounts of atrazine in only four of 71 drinking water wells in the state’s agricultural region last year. The highest level was 1.52 ppb, below the current federal limit of 3 ppb for municipal drinking water.
“We have seen, over time, a statistically significant decrease in concentrations of atrazine in monitoring wells in those sandy areas,” Greg Buzicky, director of agronomy and plant protection for the Minnesota Department of Agriculture, told the Pioneer Press, referring to the agricultural areas of Minnesota where atrazine tends to be used.
Legislators Pointing Fingers
Both sides have accused the other of avoiding sensible debate in order to play politics with the issue.
A year ago, the European Union banned atrazine in its member states. However, Syngenta, the Swiss-based manufacturer of atrazine, vigorously backs its product’s safety and says it meets EPA requirements. The use of atrazine, Syngenta spokeswoman Sherry Ford told the Pioneer Press, is “a science issue that has made the leap into the political realm.”
Rep. Jean Wagenius (D-Minneapolis) tried to attach atrazine-testing language to an ethanol bill earlier this year. Since the bill would encourage corn production and atrazine use, she said the legislature shouldn’t pass it without more discussion about atrazine’s possible effects, reported the Pioneer Press.
The newspaper continued, “The chairman of the House Environment and Natural Resources Committee, however, wouldn’t let her introduce her amendment. Rep. Tom Hackbarth, R-Cedar, said it wasn’t appropriate because, among other things, her amendment didn’t pertain to the bill.”
Wagenius told the Pioneer Press that Hackbarth’s ruling was the first time in her 19 years on the committee that anything like that had happened to her.
“‘Groundwater is clearly within the jurisdiction of the environment committee,’ Wagenius insisted. ‘It seems they were very desperate not to talk about it.'”
Greg McConnell ([email protected]) is a Chicago-based freelance reporter and columnist.
For more information …
The Environmental Protection Agency report, White Paper on Potential Developmental Effects of Atrazine on Amphibians, is available online at http://www.epa.gov/scipoly/sap/2003/June/finaljune2002telconfreport.pdf.
