February 2003
Atrazine IRED Outlines Monitoring Program
On January 31, the EPA released the atrazine Interim Reregistration Eligibility Decision (IRED) and announced an innovative and aggressive program to protect vulnerable community drinking water systems from contamination by atrazine. The announcement by the Agency involves intensive, targeted monitoring of raw water entering certain community water systems in areas of atrazine use. "After the most extensive analysis ever conducted on atrazine, EPA has designed a protective, early alert system to implement rigorous monitoring and fine-tuned safeguards to protect drinking water in the communities where atrazine is used," said Stephen L. Johnson, EPA's Assistant Administrator for the Office of Prevention, Pesticides, and Toxic Substances. "For the most vulnerable watersheds, if the testing shows higher levels of atrazine than we consider acceptable, use of the product will be prohibited in that area."
Under this approach the main registrant of atrazine, Syngenta, is required to conduct a specialized testing program in vulnerable watersheds on a weekly basis to monitor "raw" drinking water during high-use periods for this pesticide. If the Agency's regulatory safety standards are exceeded in raw drinking water, atrazine use is canceled in that geographic area. This more stringent approach requiring weekly monitoring of "raw" drinking water during certain times of the year augments monitoring conducted under the Safe Drinking Water Act (SDWA) of "finished" drinking water. For all other areas where atrazine might be used, monitoring of finished drinking water for atrazine is routinely required under the SDWA. For these systems, detections approaching the Maximum Contaminant Level for atrazine will trigger additional monitoring and regulatory oversight.
In the IRED, the Agency has concluded that atrazine may continue to be used, provided all the precautions and the new specific measures are implemented to reduce risks to drinking water. These new measures will help ensure the continued protection of drinking water. The Agency has concluded that risks associated with exposures from food are not of concern. Exposure from residential uses and exposure to workers are low and have been addressed by changes in product use conditions. The Agency is continuing to evaluate the potential effects of atrazine on amphibians, which continue to be the subject of additional research and analysis. EPA intends to submit the issue of atrazine effects on amphibians for independent scientific peer review by the FIFRA Scientific Advisory Panel in June, and the Agency anticipates completion of an amended IRED, including consideration of effects on amphibians, by October 31, 2003. (EPA Pesticide Program Update, 2/3/03).
