Know Your Environment. Protect Your Health.

CONTAMINANT

Cyanide

STATES DETECTED

39

serves

34 million

utilities detected

2,190

states detected

0

serves

0

utilities detected

0

Overview

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.

State, National, and Health Guidelines for Drinking Water

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

National Standard Exists

Health Concerns:

  • Harm to the brain and nervous system

  • Harm to the thyroid

  • Harm to the central nervous system

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Cyanide from your water?

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Reverse Osmosis

Ion Exchange

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Cyanide around the Country

UTILITIES WITH CONTAMINATION
State Utilities People Served
Texas1,08118,856,637
Florida682,578,668
Ohio1502,139,749
Utah1371,849,627
New York1121,264,964
New Jersey861,160,667
Arizona91,081,984
Oregon15781,473
Virginia11756,797
Indiana44421,045
Delaware17383,109
Mississippi50369,260
Minnesota44228,306
Illinois8225,167
Alaska8223,645
Iowa142199,115
California29175,339
West Virginia43108,363
New Mexico15108,214
Tennessee3101,287
Louisiana687,277
Massachusetts780,571
Oklahoma279,708
Rhode Island573,527
Alabama1057,765
North Carolina2145,061
Washington1040,306
Michigan1130,666
Arkansas1823,893
Georgia821,271
Missouri69,773
Wisconsin33,525
Kentucky13,490
Colorado12,817
Vermont1485
Maine4363
Maryland1325
Nebraska2265
Connecticut150

Utilities with the highest amounts of cyanide, 2021-2023

ALL UTILITIES
LARGE UTILITIES
Utility Location Tests Average level People served
Sinclairville VillageSinclairville, NY1 of 3237.0 ppb772
Aaseby CourtThief River Falls, MN2 of 5234.0 ppb50
Geneva Water District #8Geneva, NY1 of 3200.0 ppb580
Geneva City*Geneva, NY1 of 3200.0 ppb13,914
RidgecrestPflugerville, TX1 of 1180.0 ppb1,968
Fort Bend County Municipal Utility District 41Houston, TX1 of 1170.0 ppb4,317
Harris County Municipal Utility District 6 Carriage Lane*Houston, TX1 of 1170.0 ppb3,936
Northwest Harris County Municipal Utility District 6Houston, TX1 of 1170.0 ppb2,133
Harris County Municipal Utility District 468Houston, TX1 of 1170.0 ppb7,683
City of Byers*Byers, TX1 of 1169.0 ppb496
Dean Dale Special Utility District*Wichita Falls, TX1 of 1169.0 ppb3,747
City of Clyde*Clyde, TX4 of 4168.5 ppb3,811
City of Cottonwood ShoresCottonwood Shores, TX3 of 3160.0 ppb1,725
StrandquistStrandquist, MN2 of 5156.0 ppb68
Harris County Municipal Utility District 196*Houston, TX2 of 2155.0 ppb6,543
Ponderosa Community Club Inc.Leavenworth, WA2 of 2151.0 ppb1,170
City of Freeport Slaughter RoadFreeport, TX1 of 1150.0 ppb40
Verdel, Village ofLynch, NE1 of 1149.0 ppb30
City of MidlandMidland, TX1 of 1146.0 ppb142,344
City of Bowie*Bowie, TX3 of 3143.0 ppb5,219
Amon G Carter Lake Water Supply CorporationBowie, TX3 of 3143.0 ppb750
City of BrenhamBrenham, TX1 of 1140.0 ppb19,048
Country Estates Mobile Home ParkPinewood, MN1 of 2140.0 ppb90
Harris County Municipal Utility District 162Houston, TX1 of 1140.0 ppb2,661
Harris County Municipal Utility District 5Houston, TX1 of 1140.0 ppb5,487
Harris County Municipal Utility District 276*Houston, TX1 of 1140.0 ppb4,926
City of ShoreacresShoreacres, TX1 of 1140.0 ppb1,493
City of CleburneCleburne, TX3 of 3139.3 ppb30,573
Browns Pool and ParkSan Angelo, TX1 of 1139.0 ppb50
City of CrosbytonCrosbyton, TX1 of 1138.0 ppb1,741
Northwest Harris County Municipal Utility District 21*Houston, TX3 of 3136.7 ppb1,638
Swenson Water Supply CorporationAspermont, TX1 of 1135.0 ppb32
Tri Try WaterAspermont, TX1 of 1135.0 ppb49
City of Aspermont*Aspermont, TX1 of 1135.0 ppb858
Harris County MUD 53Houston, TX2 of 2135.0 ppb17,856
American Legion Mia Post 231Pottsboro, TX3 of 3132.0 ppb141
Rra Preston Shores Water System*Wichita Falls, TX3 of 3132.0 ppb2,163
City of AthensAthens, TX1 of 1131.0 ppb17,934
Addicks Utility DistrictHouston, TX1 of 1130.0 ppb7,017
Harris County Municipal Utility District 400 - West*Houston, TX1 of 1130.0 ppb5,172
Harmony Estates Mobile Home ParkSouth Charleston, OH1 of 1127.0 ppb507
Paradise Point SubdivisionAustin, TX2 of 3126.7 ppb528
West Harris County Municipal Utility District 15*Houston, TX2 of 2125.0 ppb834
Rocky Point EstatesPflugerville, TX3 of 3124.3 ppb441
Thompson Heights Water SystemDenison, TX3 of 3124.3 ppb396
City of Denison*Denison, TX3 of 3124.3 ppb22,682
Munson Point Property Owners AssociationDenison, TX3 of 3124.3 ppb72
Oak Ridge South Gale Water Supply CorporationDenison, TX3 of 3124.3 ppb3,033
Northern Hills Water ServiceKaty, TX3 of 3124.3 ppb255
Flat Water Supply CorporationFlat, TX3 of 3123.3 ppb180

* 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
Geneva City*Geneva, NY1 of 3200.0 ppb13,914
City of MidlandMidland, TX1 of 1146.0 ppb142,344
City of BrenhamBrenham, TX1 of 1140.0 ppb19,048
City of CleburneCleburne, TX3 of 3139.3 ppb30,573
Harris County MUD 53Houston, TX2 of 2135.0 ppb17,856
City of AthensAthens, TX1 of 1131.0 ppb17,934
City of Denison*Denison, TX3 of 3124.3 ppb22,682
City of Gatesville*Gatesville, TX3 of 3123.3 ppb16,135
City of Odessa*Odessa, TX3 of 3116.5 ppb123,334
Ector County Utility DistrictOdessa, TX3 of 3116.5 ppb15,300
City of Mesquite*Mesquite, TX1 of 1113.5 ppb152,020
Harris County Utility District 6Houston, TX1 of 1110.0 ppb11,262
Lakeway MUD*Lakeway, TX3 of 3110.0 ppb10,512
City of GrovesGroves, TX3 of 3110.0 ppb16,452
City of LockhartLockhart, TX1 of 1110.0 ppb14,742
City of The Colony*The Colony, TX3 of 3107.6 ppb44,927
City of Midlothian*Midlothian, TX5 of 6105.0 ppb21,450
Mountain Peak SUD*Midlothian, TX5 of 6105.0 ppb16,008
Harris County MUD 102Houston, TX6 of 6103.3 ppb10,212
City of Waco*Waco, TX2 of 3100.0 ppb143,355
City of South HoustonSouth Houston, TX5 of 5100.0 ppb17,397
Harris County Municipal Utility District 285Houston, TX1 of 1100.0 ppb13,158
Harris County Municipal Utility District 49Houston, TX1 of 1100.0 ppb10,722
City of CoppellCoppell, TX8 of 995.5 ppb41,540
City of Glenn HeightsGlenn Heights, TX8 of 995.5 ppb18,090
City of IrvingIrving, TX8 of 995.5 ppb240,420
City of Red OakRed Oak, TX8 of 995.5 ppb10,934
City of DuncanvilleDuncanville, TX8 of 995.5 ppb39,500
City of Balch SpringsBalch Springs, TX8 of 995.5 ppb27,431
Dallas Water Utility*Dallas, TX8 of 995.5 ppb1,321,740
Town of AddisonAddison, TX8 of 995.5 ppb16,661
City of CarrolltonCarrollton, TX8 of 995.5 ppb136,170
City of Farmers BranchFarmers Branch, TX8 of 995.5 ppb35,991
City of Lancaster*Lancaster, TX8 of 995.5 ppb39,040
City of Cedar HillCedar Hill, TX8 of 995.5 ppb48,870
City of DeSotoDesoto, TX8 of 995.5 ppb54,060
City of Seagoville*Seagoville, TX8 of 995.5 ppb17,800
City of Mansfield*Mansfield, TX3 of 395.4 ppb77,040
Lubbock Public Water System*Lubbock, TX5 of 593.2 ppb275,041
MokenaMokena, IL1 of 193.0 ppb19,887
City of Abilene*Abilene, TX18 of 1893.0 ppb125,182
City of Beaumont Water Utility Department*Beaumont, TX3 of 490.0 ppb115,282
City of Weatherford*Weatherford, TX3 of 389.2 ppb32,209
City of BonhamBonham, TX3 of 389.2 ppb10,386
City of Port ArthurPort Arthur, TX2 of 386.7 ppb53,818
City of Georgetown*Georgetown, TX25 of 2786.3 ppb133,743
City of Mabank*Mabank, TX2 of 385.6 ppb11,349
Harris County MUD 165Houston, TX4 of 584.0 ppb30,483
City of Rosenberg*Rosenberg, TX5 of 584.0 ppb42,158
West Travis County Regional WS*Austin, TX2 of 383.3 ppb28,215

* 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.

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