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EWG's Tap Water Database — 2021 UPDATE

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Atrazine

City of Watsonville

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

 

56

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
2015N/A00N/A
2016ND280ND
2017N/A00N/A
2018N/A00N/A
2019ND280ND

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
2016-03-159590-006-0930ND
2016-03-159590-009-1015ND
2016-03-159590-014-1120ND
2016-03-159590-015-1050ND
2016-03-159590-007-1145ND
2016-03-159590-010-0950ND
2016-03-159590-016-1120ND
2016-03-159590-013-0915ND
2016-03-159590-029-1050ND
2016-03-159590-011-1205ND
2016-03-159590-030-0830ND
2016-03-159590-012-1015ND
2016-06-149590-007-1045ND
2016-06-149590-010-0950ND
2016-06-149590-012-1220ND
2016-06-149590-013-0840ND
2016-06-149590-011-1315ND
2016-06-149590-009-1050ND
2016-06-149590-014-0850ND
2016-06-149590-015-1300ND
2016-06-149590-006-0910ND
2016-06-149590-016-1020ND
2016-06-149590-029-1000ND
2016-06-149590-030-1020ND
2016-06-149590-004-1210ND
2016-06-209590-005-1510ND
2016-09-139590-004-1400ND
2016-09-139590-005-1440ND
2019-04-309590-009-0820ND
2019-04-309590-016-0820ND
2019-04-309590-006-0750ND
2019-04-309590-015-0725ND
2019-04-309590-005-0915ND
2019-04-309590-007-1050ND
2019-04-309590-014-0750ND
2019-04-309590-029-0850ND
2019-04-309590-013-0720ND
2019-04-309590-010-0930ND
2019-04-309590-004-0830ND
2019-04-309590-012-1340ND
2019-04-309590-030-0730ND
2019-04-309590-011-1000ND
2019-08-219590-030-1020ND
2019-08-219590-029-0830ND
2019-08-219590-004-0820ND
2019-08-219590-016-0850ND
2019-08-219590-005-0910ND
2019-08-219590-015-0720ND
2019-08-219590-006-0730ND
2019-08-219590-014-0735ND
2019-08-219590-007-0815ND
2019-08-219590-013-0705ND
2019-08-219590-009-0755ND
2019-08-219590-012-0750ND
2019-08-219590-010-1000ND
2019-09-059590-011-1050ND