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EWG's Tap Water Database — 2021 UPDATE

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Atrazine

California American Water Company - Parkway

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.

MORE ABOUT THIS CONTAMINANT

 

69

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2014N/A00N/A
2015ND340ND
2016N/A00N/A
2017ND10ND
2018ND340ND
2019N/A00N/A

ppb = parts per billion

State and national drinking water standards and health guidelines

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
2015-04-091225-014-1025ND
2015-04-131225-013-1140ND
2015-04-131225-011-1030ND
2015-04-131225-002-1115ND
2015-04-131225-008-1040ND
2015-04-141225-023-1120ND
2015-04-141225-025-1140ND
2015-04-141225-016-0955ND
2015-04-141225-017-1010ND
2015-04-141225-021-1040ND
2015-04-141225-022-1100ND
2015-04-231225-018-0925ND
2015-04-231225-024-1020ND
2015-04-231225-006-0830ND
2015-04-231225-026-0950ND
2015-04-231225-015-0910ND
2015-04-281225-003-1005ND
2015-07-151225-021-1040ND
2015-07-151225-023-1135ND
2015-07-151225-015-0840ND
2015-07-151225-022-1110ND
2015-07-151225-014-1030ND
2015-07-151225-025-1225ND
2015-07-151225-002-0940ND
2015-07-201225-013-0845ND
2015-07-201225-003-1030ND
2015-07-201225-006-0950ND
2015-07-201225-008-0930ND
2015-07-201225-024-1150ND
2015-07-221225-011-1045ND
2015-07-221225-026-1000ND
2015-07-221225-018-0925ND
2015-07-291225-016-1015ND
2015-07-291225-017-0935ND
2017-12-191225-012-1300ND
2018-03-191225-012-1345ND
2018-05-011225-015-0845ND
2018-05-011225-022-0955ND
2018-05-011225-008-1200ND
2018-05-011225-021-0900ND
2018-05-011225-025-0810ND
2018-05-011225-003-1118ND
2018-05-011225-023-0955ND
2018-05-021225-006-0837ND
2018-05-021225-002-1143ND
2018-05-021225-017-1155ND
2018-05-031225-014-1125ND
2018-05-031225-026-1040ND
2018-05-031225-024-1015ND
2018-05-031225-013-0850ND
2018-05-241225-018-1050ND
2018-05-241225-011-1010ND
2018-07-301225-016-0810ND
2018-08-089590-002-1100ND
2018-08-099590-017-0835ND
2018-08-099590-016-0930ND
2018-08-099590-006-1140ND
2018-08-149590-022-0910ND
2018-08-149590-021-1005ND
2018-08-149590-023-0830ND
2018-08-149590-015-1020ND
2018-08-149590-013-1145ND
2018-08-149590-011-0900ND
2018-08-149590-025-0740ND
2018-08-149590-008-1050ND
2018-08-159590-018-1210ND
2018-08-159590-024-1250ND
2018-08-159590-026-1255ND
2018-10-089590-016-0935ND