Know Your Environment. Protect Your Health.

Atrazine

Utrwd Regional Water Treatment Plant

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.

 

29

Samples

0

Samples exceeding legal limit (MCL)

8

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20180.1000 ppb43ND - 0.200 ppb
20190.120 ppb550.1000 ppb - 0.200 ppb
20200.180 ppb550.1000 ppb - 0.300 ppb
20210.0800 ppb52ND - 0.200 ppb
20220.0800 ppb53ND - 0.200 ppb
20230.0600 ppb53ND - 0.1000 ppb

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
2018-02-13Q1805957001ND
2018-06-05Q18223190010.200 ppb
2018-09-13Q18365700030.1000 ppb
2018-09-25Q18382560010.1000 ppb
2019-03-07Q19099100070.1000 ppb
2019-06-24Q19395740010.1000 ppb
2019-09-26Q19693620010.1000 ppb
2019-10-02Q19711120010.200 ppb
2019-12-18Q19808080010.1000 ppb
2020-03-09Q20084480010.200 ppb
2020-05-20Q20200890010.200 ppb
2020-08-18Q20328590010.1000 ppb
2020-08-18Q20328590060.300 ppb
2020-11-04Q20427530010.1000 ppb
2021-02-23Q21045960010.200 ppb
2021-06-22Q2116334001ND
2021-09-27Q2126305001ND
2021-09-27Q21263050020.200 ppb
2021-11-12Q2131799001ND
2022-01-25Q22024360010.1000 ppb
2022-06-21Q2217160002ND
2022-09-15Q22276730070.200 ppb
2022-09-15Q22276730080.1000 ppb
2022-11-22Q2235058001ND
2023-03-07Q23089010020.1000 ppb
2023-06-13Q23224870010.1000 ppb
2023-08-02Q2331445005ND
2023-08-02Q2331445006ND
2023-11-10Q23483070010.1000 ppb