Environmental Working Group Releases Another Atrazine Report

The Environmental Working Group (EWG) recently released another report on atrazine in drinking water. In 1991, EPA established an atrazine drinking water standard of 3 ppb, typically based on an annual average of quarterly samples. This report focuses on the increases in atrazine concentration in runoff from spring rains and summarizes atrazine monitoring data in several Midwestern states. Since atrazine is the second most commonly used herbicide in the U.S., it continues to show up in drinking water. But one should carefully read this report, as EPA’s standard is based on an annual average of quarterly samples, and many systems have figured out appropriate treatment for the increased atrazine concentrations in the spring runoff in order to maintain compliance.