Menu

EWG's Tap Water Database — 2019 UPDATE

Donate

Atrazine

City of Houston

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.

 

166

Samples

0

Samples exceeding legal limit (MCL)

72

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
20120.0766 ppb4111ND - 0.490 ppb
20130.244 ppb2321ND - 0.420 ppb
20140.181 ppb1410ND - 0.610 ppb
20150.0533 ppb3611ND - 0.250 ppb
20160.148 ppb2611ND - 0.770 ppb
20170.118 ppb2611ND - 0.910 ppb

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
2012-01-31AB79849ND
2012-01-31AB798520.110 ppb
2012-01-31AB79850ND
2012-01-31AB79847ND
2012-01-31AB79851ND
2012-02-01AB798440.230 ppb
2012-02-01AB798430.210 ppb
2012-02-01AB798460.1000 ppb
2012-02-01AB798450.490 ppb
2012-04-10AB86429ND
2012-04-10AB86427ND
2012-04-10AB86430ND
2012-04-10AB86428ND
2012-04-10AB86431ND
2012-05-23AB90945ND
2012-05-23AB90946ND
2012-05-23AB90939ND
2012-05-23AB90943ND
2012-05-23AB90942ND
2012-05-23AB90944ND
2012-06-11AB922170.410 ppb
2012-06-12AB92383ND
2012-06-12AB92386ND
2012-06-12AB92384ND
2012-07-24AB96072ND
2012-07-24AB96069ND
2012-07-24AB96067ND
2012-07-24AB96071ND
2012-07-24AB96070ND
2012-07-24AB96066ND
2012-07-24AB96068ND
2012-07-24AB96065ND
2012-11-08AC049260.330 ppb
2012-11-08AC049240.330 ppb
2012-11-08AC049280.320 ppb
2012-11-08AC049250.330 ppb
2012-11-19AC05465ND
2012-11-19AC05463ND
2012-11-19AC05461ND
2012-11-19AC05464ND
2012-11-19AC054620.280 ppb
2013-02-25AC116270.300 ppb
2013-02-25AC116240.300 ppb
2013-02-25AC116300.300 ppb
2013-02-25AC116280.290 ppb
2013-02-25AC116290.270 ppb
2013-02-26AC118490.250 ppb
2013-03-11AC129650.230 ppb
2013-03-11AC129680.220 ppb
2013-03-11AC129660.210 ppb
2013-03-11AC129690.210 ppb
2013-06-12AC221410.300 ppb
2013-06-12AC221400.270 ppb
2013-06-12AC221380.340 ppb
2013-06-13AC221460.420 ppb
2013-06-13AC221390.270 ppb
2013-08-08AC272770.260 ppb
2013-08-08AC272760.320 ppb
2013-08-08AC272780.260 ppb
2013-08-08AC272740.190 ppb
2013-08-08AC272750.250 ppb
2013-10-24AC33318ND
2013-12-16AC376950.160 ppb
2013-12-17AC37823ND
2014-02-03AC411280.130 ppb
2014-03-14AC471830.360 ppb
2014-03-14AC471840.360 ppb
2014-03-14AC471850.390 ppb
2014-04-16AC509280.120 ppb
2014-04-16AC509290.130 ppb
2014-04-17AC51177ND
2014-06-03AC558310.180 ppb
2014-06-03AC558260.610 ppb
2014-07-15AC597330.120 ppb
2014-07-15AC597290.130 ppb
2014-10-08AC69250ND
2014-12-18AC75488ND
2014-12-18AC75489ND
2015-03-04AC83061ND
2015-03-04AC830590.1000 ppb
2015-03-05AC83064ND
2015-03-05AC830650.1000 ppb
2015-03-24AC85944ND
2015-06-04AC94707ND
2015-06-04AC94705ND
2015-06-04AC94710ND
2015-06-04AC94709ND
2015-06-04AC947060.130 ppb
2015-06-04AC947080.190 ppb
2015-07-22AD00679ND
2015-07-22AD00678ND
2015-09-17AD076490.130 ppb
2015-09-17AD07648ND
2015-10-22AD11601ND
2015-10-22AD11600ND
2015-10-22AD11602ND
2015-10-22AD11596ND
2015-10-22AD11599ND
2015-10-22AD11598ND
2015-10-22AD11597ND
2015-11-12AD13457ND
2015-11-12AD13444ND
2015-11-12AD13456ND
2015-11-12AD13453ND
2015-11-12AD134430.250 ppb
2015-11-12AD13452ND
2015-11-12AD13455ND
2015-11-12AD134540.230 ppb
2015-11-16AD136990.220 ppb
2015-11-16AD137010.220 ppb
2015-11-16AD137000.210 ppb
2015-11-17AD139070.140 ppb
2015-12-08AD16048ND
2015-12-08AD16049ND
2016-03-03AD27014ND
2016-03-16AD292230.480 ppb
2016-03-16AD292220.440 ppb
2016-03-17AD294320.460 ppb
2016-03-17AD29430ND
2016-03-17AD29435ND
2016-03-17AD294330.420 ppb
2016-03-23AD30249ND
2016-03-23AD30250ND
2016-03-23AD302480.770 ppb
2016-03-23AD30251ND
2016-06-08AD39863ND
2016-06-08AD39861ND
2016-06-08AD398620.240 ppb
2016-06-08AD39860ND
2016-06-15AD408290.240 ppb
2016-06-16AD41041ND
2016-06-16AD41042ND
2016-09-20AD504590.220 ppb
2016-09-20AD504600.210 ppb
2016-09-21AD508890.150 ppb
2016-09-21AD50890ND
2016-10-06AD52704ND
2016-10-06AD527060.210 ppb
2016-10-06AD52705ND
2016-12-02AD60483ND
2017-01-26AD67327ND
2017-01-26AD67326ND
2017-02-28AD726140.260 ppb
2017-02-28AD726150.250 ppb
2017-03-01AD728830.310 ppb
2017-03-01AD728820.370 ppb
2017-03-02AD732830.330 ppb
2017-03-02AD732840.910 ppb
2017-03-28AD77273ND
2017-03-28AD772740.130 ppb
2017-04-27AD81596ND
2017-04-27AD81598ND
2017-04-27AD81597ND
2017-07-06AD88548ND
2017-07-06AD88549ND
2017-07-25AD906750.160 ppb
2017-07-26AD90935ND
2017-07-26AD90934ND
2017-09-11AD956330.120 ppb
2017-09-11AD95634ND
2017-09-26AD98128ND
2017-09-26AD981290.120 ppb
2017-09-26AD981300.110 ppb
2017-11-07AE03932ND
2017-11-07AE03938ND
2017-12-04AE06640ND