Know Your Environment. Protect Your Health.

Atrazine

Clarence Cannon Wholesale Water Commission

Atrazine is a herbicide commonly detected in drinking water that comes from cornfield and other agricultural runoff. It is a hormone disrupter that harms the male and female reproductive systems of people and wildlife. Read More.

Federal laws allow up to 3 parts per billion of atrazine in treated tap water. Water suppliers average atrazine measurements collected over a year, which means that the reported values underestimate intense spikes of elevated exposures during the periods in late spring and early summer when atrazine is applied in large amounts on farm fields.

Human epidemiological studies suggest that federal standards for atrazine are insufficient to protect public health. In 1999 the California Office of Environmental Health Hazard Assessment set a public health goal of 0.15 parts per billion for atrazine in drinking water, based on a study finding increased rates of breast cancer in rats exposed to the chemical. California’s legal maximum for atrazine in tap water is 1 ppb.

Click here to read more about atrazine.

 

23

Samples

0

Samples exceeding legal limit (MCL)

9

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.500 ppb43ND - 0.990 ppb
20190.125 ppb42ND - 0.250 ppb
20200.0600 ppb41ND - 0.240 ppb
20210.548 ppb42ND - 1.74 ppb
20220.0625 ppb41ND - 0.250 ppb
2023ND30ND

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.1 ppb

The EWG Health Guideline of 0.1 ppb for atrazine was defined by EWG based on epidemiological studies of human exposure to atrazine in drinking water.. This health guideline protects against harm to the developing fetus, harm to the reproductive system and hormone disruption.

EPA Maximum Contaminant
Level (MCL): 3 ppb

The legal limit for atrazine, established in 1991, was based on a toxicity study in laboratory animals conducted in the 1980s. This limit does not fully protect against harm to the reproductive system, harm to the developing fetus, and hormone disruption.

ppb = parts per billion

All test results

Date Lab ID Result
2018-02-19AD148290.990 ppb
2018-05-14AD20834ND
2018-08-06AD315920.330 ppb
2018-11-21AD361150.680 ppb
2019-03-04AD39917ND
2019-05-28AD478010.250 ppb
2019-08-20AD54390ND
2019-11-18AD584150.250 ppb
2020-02-202001419ND
2020-05-262008846ND
2020-08-242013072ND
2020-11-1820179680.240 ppb
2021-02-232100616ND
2021-05-2521108881.74 ppb
2021-08-252115230ND
2021-11-2221194540.450 ppb
2022-02-222201910ND
2022-05-242211507ND
2022-09-072216191ND
2022-12-0622211090.250 ppb
2023-03-072300531ND
2023-05-252308078ND
2023-08-272313254ND