Drinking Water
Levels of atrazine in U.S. waters are well within the federal lifetime drinking water standard of 3 parts-per-billion — a level containing a 1,000-fold safety buffer.
In 2008, none of the 122 Community Water Systems monitored in 10 states exceeded the federal standards set for atrazine in drinking water or raw water.
  • EPA sets very conservative standards for chemicals in drinking water that are protective of human health. In the case of atrazine, EPA adopted a standard of 3 parts per billion (ppb) in drinking water. This standard is 1,000 times safer than a level shown to have no health effects in laboratory animals.
    To put this in perspective, a 150-pound adult could drink 21,000 gallons of water containing 3 ppb of atrazine every day for 70 years and still not reach levels shown to have no effects in lab studies.

  • In raw water, atrazine concentrations declined significantly between 1994 and 2006 at 103 frequently monitored sites. This is due in large part to farmers' use of best management practices such as buffer strips (plantings used to separate crops from waterways).
Expert View
"Risk assessments for cumulative exposures to triazine residues via drinking water based on currently registered uses of atrazine and simazine are not of concern."