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EWG's Tap Water Database — 2019 UPDATE

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Cyanide

Status: National drinking water standard exists

 

Cyanide is a toxic chemical that causes central nervous system and thyroid toxicity. Water contamination is generally the result of metal mining and chemical industry waste, runoff from agriculture and road salts used for melting ice.

2015-2017:

FOUND
FOUND ABOVE HEALTH GUIDELINES

37

states detected

1,884

utilities detected

32 million

people served

0

states over health guideline

0

utilities over health guideline

0

people served over health guideline

Health concerns for cyanide

Harm to the brain and nervous system

Harm to the thyroid

Harm to the central nervous system

State and national drinking water standards and health guidelines

EWG Health Guideline 150 ppb

The EWG Health Guideline of 150 ppb for cyanide was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against harm to the brain and nervous system.

EPA Maximum Contaminant
Level (MCL) 200 ppb

The legal limit for cyanide, established in 1992, was based on a 1955 toxicity study conducted in laboratory animals. This limit does not include any additional consideration of children’s health.

ppb = parts per billion

States reporting cyanide in drinking water

UTILITIES WITH CONTAMINATION
State UtilitiesPeople Served
Texas1,11817,308,961
Florida933,567,607
Utah1571,957,546
Louisiana221,447,433
New York951,446,708
New Jersey231,286,628
Oklahoma6815,162
Missouri31789,805
District Of Columbia3648,882
Kentucky61589,657
Wisconsin11397,954
California17364,682
Mississippi44345,644
Virginia6216,042
Connecticut19177,729
West Virginia28113,589
North Carolina14106,975
Massachusetts6103,417
Ohio1183,969
Tennessee882,328
North Dakota380,555
Indiana2759,297
New Mexico544,155
Minnesota2530,160
Arkansas1429,203
Alabama327,576
Rhode Island312,700
Washington811,215
Colorado24,562
Illinois41,855
Vermont11,695
Nebraska61,530
Alaska31,311
Arizona21,299
Wyoming2980
Georgia185
Oregon135
Maine125
MORE
LESS

Filtering technologies that reduce cyanide

reverse osmosis icon

Reverse Osmosis

ion exchange icon

Ion Exchange

Utilities with the highest amounts of cyanide, 2015-2017

ALL UTILITIES
LARGE UTILITIES
UtilityLocationTestsAverage levelPeople served
Middletown Water UtilityMiddletown, IN1 of 1900.0 ppb2,050
Chesterfield Water DepartmentChesterfield, IN1 of 1800.0 ppb2,800
Elpine VillageBemidji, MN1 of 2380.0 ppb125
Rambo Water District #1 Inc.Rogers, AR5 of 7322.9 ppb90
StrandquistStrandquist, MN2 of 4230.0 ppb71
Aaseby CourtThief River Falls, MN2 of 4212.5 ppb50
FreebornFreeborn, MN1 of 2195.0 ppb297
Jackson, Village ofEmerson, NE1 of 2195.0 ppb250
New Harmony Water UtilityNew Harmony, IN1 of 3191.0 ppb1,633
Crab Orchard, Village of*Crab Orchard, NE1 of 2189.0 ppb48
Johnson County Rural Water District #1 West*Tecumseh, NE1 of 2189.0 ppb499
City of Anson*Anson, TX1 of 1184.0 ppb2,500
Whispering Pines ParkTampa, FL1 of 1180.0 ppb50
Harris County Municipal Utility District 419Houston, TX1 of 1180.0 ppb7,389
Fort Bend County Municipal Utility District 118Houston, TX1 of 1180.0 ppb3,960
Harris County MUD 489Houston, TX1 of 1180.0 ppb486
Harris County Municipal Utility District 418*Houston, TX1 of 1180.0 ppb0
Valley Municipal Utility District 2 Rancho ViejoBrownsville, TX3 of 3173.3 ppb2,500
Township 29 Water AssociationOak Harbor, WA1 of 1172.0 ppb38
Ashland Water and Sewer Department*Ashland, MA1 of 1172.0 ppb16,593
Silver Palm Mobile HomesMiami, FL1 of 1170.0 ppb250
Sienna Plantation Municipal Utility District 3Houston, TX2 of 2170.0 ppb7,029
Sienna Plantation Municipal Utility District 2Houston, TX2 of 2170.0 ppb4,785
Sienna Plantation Municipal Utility District 4Houston, TX2 of 2170.0 ppb474
Sienna Plantation Municipal Utility District 10Houston, TX2 of 2170.0 ppb4,992
Fort Bend County Municipal Utility District 142Houston, TX1 of 1170.0 ppb8,184
Sienna Plantation Municipal Utility District 1*Sugar Land, TX2 of 2170.0 ppb24
Klein Public Utility DistrictHouston, TX1 of 1170.0 ppb3,495
West Harris County Municipal Utility District 15*Houston, TX2 of 2165.0 ppb654
Harris County Municipal Utility District 383*Houston, TX1 of 1160.0 ppb4,062
Harris County Municipal Utility District 44Houston, TX1 of 1160.0 ppb2,304
Addicks Utility DistrictHouston, TX1 of 1160.0 ppb4,998
Harris County Municipal Utility District 70Houston, TX1 of 1160.0 ppb5,763
Corpus Christi Naval Air StationCorpus Christi, TX12 of 13153.1 ppb8,349
Violet Water Supply CorporationRobstown, TX12 of 13153.1 ppb2,622
City of Corpus Christi*Corpus Christi, TX12 of 13153.1 ppb325,733
South Texas Water Authority*Kingsville, TX12 of 13153.1 ppb0
Harris County Municipal Utility District 149Houston, TX1 of 1150.0 ppb3,675
Harris County Municipal Utility District 163Houston, TX1 of 1150.0 ppb5,628
Ricewood Municipal Utility DistrictHouston, TX1 of 1150.0 ppb4,986
Strawberry EstatesAustin, TX1 of 1149.0 ppb129
City of Baird*Baird, TX3 of 3148.7 ppb2,223
Lakeshore Sites WaterHaskell, TX1 of 1147.0 ppb100
City of Slaton*Slaton, TX1 of 1147.0 ppb6,077
Paint Creek Water Supply Corporation*Stamford, TX1 of 1147.0 ppb479
City of Big Spring*Big Spring, TX1 of 1145.0 ppb27,282
City of OdonnellOdonnell, TX1 of 1145.0 ppb800
Howard County Water Control and Improvement District 1*Coahoma, TX1 of 1145.0 ppb0
Fort Bend County Municipal Utility District 115 Riverstone*Sugar Land, TX1 of 1140.0 ppb1,434
Northwest Harris County Municipal Utility District 23Bellaire, TX1 of 1140.0 ppb3,528

* 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 Cyanide, but it likely has the contaminant in its water supply.

UtilityLocationTestsAverage levelPeople served
Ashland Water and Sewer Department*Ashland, MA1 of 1172.0 ppb16,593
City of Corpus Christi*Corpus Christi, TX12 of 13153.1 ppb325,733
City of Big Spring*Big Spring, TX1 of 1145.0 ppb27,282
City of HuttoHutto, TX1 of 1140.0 ppb16,638
City of Sweetwater*Sweetwater, TX3 of 3133.0 ppb11,760
Harris County FWSD 51*Houston, TX2 of 2130.0 ppb10,401
City of Abilene*Abilene, TX15 of 15129.8 ppb123,886
City of Waco*Waco, TX15 of 17122.4 ppb130,194
City of Odessa*Odessa, TX1 of 1122.0 ppb97,802
Ector County Utility DistrictOdessa, TX1 of 1122.0 ppb15,300
Harris County MUD 53Houston, TX2 of 2120.0 ppb16,164
Brownsville Public Utilities Board*Brownsville, TX6 of 6120.0 ppb176,362
Langham Creek Utility District*Houston, TX2 of 3116.7 ppb10,377
Town of ProsperProsper, TX7 of 8111.9 ppb22,650
City of FateFate, TX7 of 8111.9 ppb14,327
City of AllenAllen, TX7 of 8111.9 ppb93,528
City of MurphyMurphy, TX7 of 8111.9 ppb19,850
City of Frisco*Frisco, TX7 of 8111.9 ppb159,000
Town of Little Elm*Little Elm, TX7 of 8111.9 ppb31,355
City of Royse CityRoyse City, TX7 of 8111.9 ppb11,988
City of SachseSachse, TX7 of 8111.9 ppb23,681
City of McKinney*Mckinney, TX7 of 8111.9 ppb169,710
City of Forney*Forney, TX7 of 8111.9 ppb19,122
City of Rockwall*Rockwall, TX7 of 8111.9 ppb40,620
East Fork SUDWylie, TX7 of 8111.9 ppb13,596
City of RichardsonRichardson, TX7 of 8111.9 ppb104,300
City of Plano*Plano, TX7 of 8111.9 ppb277,720
City of GarlandGarland, TX7 of 8111.9 ppb236,786
City of Mesquite*Mesquite, TX7 of 8111.9 ppb143,484
City of Terrell*Terrell, TX7 of 8111.9 ppb24,744
City of WylieWylie, TX7 of 8111.9 ppb41,043
City of RowlettRowlett, TX7 of 8111.9 ppb58,407
City of LeanderLeander, TX3 of 3110.0 ppb43,764
City of KilleenKilleen, TX9 of 9101.1 ppb140,806
US Army South Fort HoodFort Hood, TX9 of 9101.1 ppb35,669
City of Harker HeightsHarker Heights, TX9 of 9101.1 ppb30,365
City of Copperas Cove*Copperas Cove, TX9 of 9101.1 ppb33,919
City of BeltonBelton, TX9 of 9101.1 ppb21,214
City of Snyder*Snyder, TX1 of 1100.0 ppb10,783
Harris County MUD 200 Cranbrook*Houston, TX3 of 3100.0 ppb14,697
City of Nederland*Nederland, TX2 of 396.7 ppb17,545
East Rio Hondo WSC*Rio Hondo, TX3 of 393.3 ppb21,726
Brookesmith Special Utility District*Brownwood, TX9 of 1292.5 ppb11,289
City of BrownwoodBrownwood, TX9 of 1292.5 ppb18,965
City of Georgetown*Georgetown, TX25 of 2792.2 ppb98,776
Lubbock Public Water System*Lubbock, TX4 of 591.6 ppb235,398
City of San JuanSan Juan, TX5 of 690.0 ppb30,000
City of Gatesville*Gatesville, TX2 of 386.7 ppb14,430
City of MidlandMidland, TX1 of 282.5 ppb132,950
City of Austin Water & Wastewater*Austin, TX8 of 982.2 ppb981,783

* 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 Cyanide, but it likely has the contaminant in its water supply.