by Sarah Scott, Support Staff

Photo credit: tpmartins' photostream on flickr.com
Photo credit: tpmartins’ photostream on flickr.com

Atrazine, one of the family of triazine herbicides, has been widely used to control broadleaf and grassy weeds in agriculture and lawns. First approved for use in 1959, it is widely used in corn growing; over 75% of corn crops nationwide are treated with atrazine every year. Swiss-based Syngenta, one of the manufacturers of atrazine, touts that it is an economical form of weed control that prevents crop damage, and that it also has positive environmental effects because farmers can spray atrazine instead of tilling the soil to reduce weeds, thus preventing soil erosion and reducing carbon dioxide gas from tractors.

However, the use of atrazine is not without controversy. In 2005, atrazine was banned in the European Union; this was part of a larger ban on chemicals that have a high tendency to leach into water. Atrazine does not degrade quickly in the environment – it persists for months in soil and can last for a year or more in water. As it degrades, it forms other toxic chemicals.

There are concerns that atrazine contamination of drinking water may be linked to low birth weights, menstrual problems and cancers in people. High doses of herbicides including atrazine are linked to frog deformities and intersex frogs, specifically male frogs that develop female organs. Atrazine is a restricted-use pesticide in the U.S. (only certified people can apply it), and it is not labeled for use within fifty feet of a well or sinkhole, and within sixty-six feet of any point where any field surface water runs off into streams or rivers. Interestingly, there are no restrictions on other points along streams, and drainage ditches are sometimes excluded from these regulations.

The Environmental Protection Agency (EPA) has set a limit of 3 ppb (parts per billion) for atrazine in drinking water, but does not require timely notification of residents when this limit is exceeded. The EPA has limited monitoring resources; of thirty monitoring sites around the state, most are sampled only once every five years, consisting of one sample taken before atrazine application and two afterwards. The problem is that this monitoring may not occur when atrazine levels are likely to be highest, such as after a heavy rain that increases levels in streams through run-off.

Since drinking water systems may only test for atrazine levels yearly, the EPA requires that the manufacturers of atrazine test more frequently. However, a recent study shows that utilities are not getting the information they need from these companies. Recently it was revealed that atrazine levels in Piqua, OH were measured by Syngenta at 59 ppb in April 2005, yet local authorities were not notified. The EPA commented that this level of exposure was safe and that Syngenta was not required to release this information.

There are also concerns about long-term, low level exposure to the chemical, especially for pregnant women. Atrazine levels may be mostly “safe” but at certain developmentally-important times during pregnancy, fetuses may be at higher risk for birth defects. In a recent study by Purdue University, levels at 0.1 ppb were linked to low birth weights.

Recently, Holiday Shores Sanitary District in Madison County, IL and forty-two other water districts, sued atrazine-makers Syngenta and Growmark to cover the costs of removing atrazine from drinking water. Water utilities commonly face the problem of atrazine removal—most water utilities do not have adequate filtering systems. EPA recommends a charcoal filter; most utilities are using sand filters as charcoal upgrades are cost-prohibitive. The lawsuit contains six counts:

  1. trespass onto the property of the water district;
  2. nuisance to the property of the water district;
  3. negligence;
  4. strict liability;
  5. violation of the Illinois Environmental Protection Act; and
  6. violation of the Illinois Water Pollutant Discharge Act.

The lawsuit will not affect whether atrazine continues to be manufactured and used—that decree would have to come from Congress. Prairie Rivers Network is watching this lawsuit with interest; given the burden atrazine causes for water treatment systems, we expect future regulations will further restrict the use of this harmful pesticide.

To learn more about atrazine, you can read a recent New York Times article

To see the specific details of the lawsuit, click here.