EWG's Tap Water Database — 2019 UPDATE



Status: National drinking water standard exists


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.




states detected


utilities detected

44 million

people served


states over health guideline


utilities over health guideline

16 million

people served over health guideline

Health concerns for atrazine

Harm to the developing fetus

Hormone disruption

Harm to the reproductive system

Changes in the nervous system

Changes in brain and behavior


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

States reporting atrazine in drinking water

State UtilitiesPeople Served UtilitiesPeople Served
North Carolina30226,93566920,565
District Of Columbia003648,882
New York56,60118635,260
South Carolina482,56811377,503
New Mexico1166239,674
Rhode Island00119,354
New Jersey0014,960

Filtering technologies that reduce atrazine

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Activated Carbon

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Reverse Osmosis

Utilities with the highest amounts of atrazine, 2015-2017

UtilityLocationTestsAverage levelPeople served
Elk County Rural Water District 2Howard, KS4 of 44.03 ppb206
Howard, City of*Howard, KS4 of 44.03 ppb642
Russell, City ofRussell, KS5 of 72.41 ppb4,484
Richmond, City ofRichmond, KS4 of 42.30 ppb457
Beloit, City of*Beloit, KS6 of 62.19 ppb3,792
Mitchell County Rural Water District 1Beloit, KS6 of 62.19 ppb345
Colby, City ofColby, KS9 of 92.14 ppb5,388
Udall, City ofUdall, KS1 of 22.05 ppb738
Carbondale, City of*Carbondale, KS4 of 41.88 ppb1,405
Hume PWSHume, MO2 of 31.87 ppb336
Parker, City ofParker, KS2 of 31.87 ppb273
Mound City, City ofMound City, KS2 of 31.87 ppb682
Linn County Rural Water District 1La Cygne, KS2 of 31.87 ppb1,200
Blue Mound, City ofBlue Mound, KS2 of 31.87 ppb275
Public Wholesale WSD 13*Mound City, KS2 of 31.87 ppb16,053
Linn County Rural Water District 2*Mound City, KS2 of 31.87 ppb1,960
Oswego, City of*Oswego, KS5 of 91.62 ppb1,781
Labette County Rural Water District 1cOswego, KS5 of 91.62 ppb285
Mitchell County Rural Water District 3*Beloit, KS4 of 41.53 ppb2,048
Tipton, City ofTipton, KS4 of 41.53 ppb207
Mitchell County Rural Water District 2*Glen Elder, KS4 of 41.53 ppb1,291
Hunter, City ofHunter, KS4 of 41.53 ppb56
Wakefield, City ofWakefield, KS1 of 11.50 ppb967
Lane, City ofLane, KS4 of 41.47 ppb222
Franklin County Rural Water District 6*Rantoul, KS4 of 41.47 ppb2,960
Concordia PWS*Concordia, MO12 of 141.47 ppb2,500
Emma PWS*Emma, MO12 of 141.47 ppb205
Maryville*Maryville, MO13 of 131.47 ppb11,972
Baxter Springs, City of*Baxter Springs, KS1 of 91.44 ppb4,073
CarthageCarthage, IL6 of 121.43 ppb2,725
Oakley, City ofOakley, KS4 of 41.41 ppb2,075
Atchison County Rural Water District 6Atchison, KS3 of 91.39 ppb670
City of Atchison*Atchison, KS3 of 91.39 ppb10,771
Atchison County Rural Water District 1Atchison, KS3 of 91.39 ppb490
Atchison County Rural Water District 3Atchison, KS3 of 91.39 ppb110
Garnett, City of*Garnett, KS7 of 111.34 ppb3,295
Anderson County Rural Water District 1Garnett, KS7 of 111.34 ppb37
West Warren-Viola U. D.Morrison, TN3 of 101.34 ppb15,954
Protection, City of*Protection, KS1 of 71.26 ppb527
Comanche County Rural Water District 1Protection, KS1 of 71.26 ppb57
Vandalia PWSVandalia, MO10 of 131.25 ppb2,529
Saline County Rural Water District 2Gypsum, KS1 of 11.20 ppb465
Riley, City ofRiley, KS2 of 41.16 ppb994
Napoleon City*Napoleon, OH24 of 281.14 ppb8,749
Florida VillageNapoleon, OH24 of 281.14 ppb350
Malinta Village*Malinta, OH24 of 281.14 ppb325
Liberty Center VillageLiberty Center, OH24 of 281.14 ppb1,180
Henry County Regional Water & Sewer District - Co. Rd. PNapoleon, OH24 of 281.14 ppb54
Henry County Regional Wsd- Sr 108Napoleon, OH24 of 281.14 ppb267
Lexington PWS*Lexington, MO8 of 131.09 ppb4,300

* This water utility supplies finished drinking water to at least one other water utility. The purchasing utility is not required to test for or report Atrazine, but it likely has the contaminant in its water supply.

UtilityLocationTestsAverage levelPeople served
Public Wholesale WSD 13*Mound City, KS2 of 31.87 ppb16,053
Maryville*Maryville, MO13 of 131.47 ppb11,972
City of Atchison*Atchison, KS3 of 91.39 ppb10,771
West Warren-Viola U. D.Morrison, TN3 of 101.34 ppb15,954
City of GardnerGardner, KS3 of 30.997 ppb20,667
Springfield Water System*Springfield, TN5 of 130.917 ppb38,305
City of Ottawa*Ottawa, KS3 of 30.883 ppb12,403
Leavenworth Water Department*Leavenworth, KS3 of 60.762 ppb36,000
Fort Leavenworth American Water Ent IncFort Leavenworth, KS1 of 10.760 ppb12,934
Public Wholesale WSD 5*Iola, KS7 of 100.681 ppb12,192
Newark City PWSNewark, OH5 of 170.674 ppb47,573
Hardin County Water District #1*Radcliff, KY2 of 80.600 ppb27,033
Murphysboro*Murphysboro, IL13 of 130.600 ppb11,915
City of Topeka*Topeka, KS35 of 370.585 ppb165,000
Thomas Hill PWSD 1*Moberly, MO7 of 120.548 ppb10,315
Indiana American Water - MuncieGreenwood, IN10 of 130.500 ppb65,708
Lewisburg Water System*Lewsiburg, TN3 of 40.486 ppb19,208
City of Olathe*Olathe, KS3 of 30.450 ppb133,062
City of Midlothian*Midlothian, TX8 of 90.428 ppb16,728
Del-Co Water Company Inc.*Delaware, OH21 of 220.428 ppb141,407
Speedway Water WorksSpeedway, IN7 of 90.400 ppb11,812
Aqua Ohio - TiffinTiffin, OH9 of 140.398 ppb17,963
Aqua Ohio - MarionMarion, OH6 of 120.398 ppb41,925
City of Parsons*Parsons, KS2 of 30.370 ppb10,174
Athens Utilities*Athens, AL2 of 120.367 ppb27,534
Piqua City PWSPiqua, OH8 of 180.365 ppb20,522
Sidney City PWSSidney, OH4 of 180.336 ppb21,229
Water District 1 of Johnson CountyKansas City, KS11 of 110.325 ppb331,900
City of Garden City*Garden City, KS1 of 40.325 ppb27,004
Hannibal*Hannibal, MO5 of 120.316 ppb17,916
Mattoon*Mattoon, IL4 of 120.313 ppb19,000
City of Beeville*Beeville, TX1 of 30.303 ppb15,039
Bedford City Utilities*Bedford, IN3 of 120.300 ppb14,000
City of Greenville*Greenville, TX3 of 30.300 ppb26,800
City of Dodge CityDodge City, KS13 of 280.297 ppb28,117
City of Rockport*Rockport, TX3 of 30.297 ppb26,450
City of PortlandPortland, TX3 of 30.297 ppb20,000
Fremont CityFremont, OH9 of 120.293 ppb16,677
Pennsylvania American Water Company - Indiana DIndiana, PA3 of 70.286 ppb24,877
Citizens Water - Indianapolis*Indianapolis, IN217 of 3850.279 ppb814,338
El Paso Water CompanyDerby, KS2 of 30.273 ppb23,234
City of Wichita*Wichita, KS2 of 30.273 ppb388,413
City of GarlandGarland, TX8 of 80.266 ppb236,786
City of MurphyMurphy, TX8 of 80.266 ppb19,850
City of WylieWylie, TX8 of 80.266 ppb41,043
East Fork SUDWylie, TX8 of 80.266 ppb13,596
City of RichardsonRichardson, TX8 of 80.266 ppb104,300
Town of ProsperProsper, TX8 of 80.266 ppb22,650
City of Frisco*Frisco, TX8 of 80.266 ppb159,000
City of AllenAllen, TX8 of 80.266 ppb93,528

* This water utility supplies finished drinking water to at least one other water utility. The purchasing utility is not required to test for or report Atrazine, but it likely has the contaminant in its water supply.