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CONTAMINANT

Perchlorate

FOUND

Exceeding guidelines

STATES DETECTED

6

serves

18 million

utilities detected

508

states detected

3

serves

349,000

utilities detected

35

Overview

Perchlorate, a component of rocket fuel, occurs both naturally and as a synthetic chemical. Ingested perchlorate interferes with thyroid function. Exposure to perchlorate during pregnancy and childhood can impair cognitive development. learn more about this contaminant

According to the EPA, perchlorate likely contaminates the water of more than 16 million Americans. Perchlorate interferes with iodine uptake in the thyroid, which can result in reduced thyroid hormones and an impact on metabolism, physical development and cognitive development. Children and developing fetuses are the most at risk from perchlorate contamination.

Perchlorate is the only unregulated contaminant for which the EPA has attempted to set a federal drinking water standard since 1996. However, the agency has yet to propose a draft limit for this contaminant. Perchlorate in drinking water is regulated in Arizona, California, Massachusetts, New Jersey, New York and Texas. California set a public health goal of 1 part per billion for perchlorate in 2015.

Click here to read more about perchlorate.

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 1 ppb

The EWG Health Guideline of 1 ppb for perchlorate 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 hormone disruption.

ppb = parts per billion

National Standard Exists

Health Concerns:

  • Hormone disruption

  • Harm to fetal growth and child development

Want to remove
Perchlorate from your water?

Try these filter technologies:

Reverse Osmosis, 

Ion Exchange, 

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Perchlorate around the Country

UTILITIES REPORTING ABOVE HEALTH GUIDELINES UTILITIES WITH CONTAMINATION
State Utilities People Served Utilities People Served
California31260,63119610,914,164
Massachusetts125,3922732,678,934
Nevada0051,931,994
New York363,000301,135,999
District Of Columbia003847,323
Vermont00188

Utilities with the highest amounts of perchlorate, 2021-2023

ALL UTILITIES
LARGE UTILITIES
Utility Location Tests Average level People served
La Verne WDLa Verne, CA272 of 3516.50 ppb32,206
Murphy Hill Ws #02Aromas, CA1 of 14.90 ppb66
Tokay Park Water CompanySacramento, CA1 of 24.65 ppb653
Tierra Buena Mobile Home Park #1Zamora, CA11 of 114.45 ppb50
Page Avenue Mutual Water CompanyFullerton, CA12 of 124.41 ppb119
River Rd. Ws #25Gonzales, CA3 of 34.40 ppb65
Marygold Mutual Water CompanyBloomington, CA92 of 934.29 ppb3,055
Locust Valley Water DistrictLocust Valley, NY42 of 724.25 ppb7,500
Bradford Run RvAguanga, CA1 of 14.20 ppb75
East Orosi Community Services DistrictVisalia, CA2 of 23.80 ppb423
Calif State Polytechnical Univ - PomonaPomona, CA419 of 4883.50 ppb5,020
City of Loma LindaLoma Linda, CA25 of 2303.29 ppb24,791
Hynes Estates Mutual Water CompanyAnaheim, CA11 of 173.21 ppb139
Mariana Ranchos County Water DistrictApple Valley, CA2 of 23.15 ppb1,495
Santa Ynez Roblar Mobile Home ParkLa Canada, CA1 of 13.00 ppb25
Foothill ApartmentsPorterville, CA1 of 13.00 ppb41
San Martin County Water DistrictSan Martin, CA89 of 1012.82 ppb518
Box Springs Mutual Water CompanyMoreno Valley, CA1 of 12.80 ppb3,542
Burlington Water DepartmentBurlington, MA7 of 72.69 ppb25,392
Gleanings For The HungrySultana, CA38 of 1372.68 ppb31
Salinas Valley State PrisonSoledad, CA1 of 12.60 ppb2,930
Fairview Water Company LLCTehachapi, CA23 of 312.53 ppb240
Westbury WDWestbury, NY26 of 572.51 ppb20,500
Loma Linda Power Plant*Loma Linda, CA16 of 202.51 ppb419
City Of Orange CoveOrange Cove, CA1 of 32.50 ppb9,780
Apple Ave. Ws #03Greenfield, CA1 of 12.50 ppb60
Anza Mutual Water CompanyAnza, CA1 of 12.40 ppb224
Mobile Home EstatesSanta Rosa, CA1 of 12.30 ppb210
Bluffs WsSalinas, CA1 of 12.20 ppb120
Sullivan Mutual WaterMorgan Hill, CA1 of 12.20 ppb53
West San Martin Water Works Inc.San Martin, CA12 of 192.19 ppb773
Plainview WDPlainview, NY172 of 3232.14 ppb35,000
Westwood Community Services DistrictWestwood, CA1 of 12.10 ppb1,662
Home Gardens County Water DistrictCorona, CA390 of 9302.04 ppb3,095
City of Corona*Corona, CA390 of 9302.04 ppb168,751
City Of Industry Waterworks Systems*La Puente, CA25 of 351.99 ppb6,111
City of ColtonColton, CA109 of 2051.85 ppb46,525
Valencia Heights Water CompanyWest Covina, CA108 of 2491.71 ppb7,775
Lincoln Avenue Water CompanyAltadena, CA108 of 2961.69 ppb16,126
Ivanhoe Public Utility DistrictIvanhoe, CA2 of 41.68 ppb4,347
Suburban Water Systems - San Jose HillsCovina, CA118 of 2251.66 ppb168,843
Palm Ranch Irrigation DistrictQuartz Hill, CA21 of 371.62 ppb5,507
Las Flores Water CompanyAltadena, CA78 of 1731.62 ppb4,847
Newhall CWD-Newhall*Santa Clarita, CA18 of 451.54 ppb17,154
Golden State Water Company - West OrangeAnaheim, CA48 of 821.52 ppb113,106
Woodville Farm Labor CenterVisalia, CA1 of 21.50 ppb646
Yuima Municipal Water District Ida*Pauma Valley, CA52 of 1711.49 ppb769
Rubio Canon Land & Water AssociationAltadena, CA191 of 3101.45 ppb9,600
Golden State WC - PlacentiaAnaheim, CA8 of 171.44 ppb49,808
Cutler Public Utility DistrictCutler, CA1 of 21.40 ppb6,200

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

UtilityLocationTestsAverage levelPeople served
La Verne WDLa Verne, CA272 of 3516.50 ppb32,206
City of Loma LindaLoma Linda, CA25 of 2303.29 ppb24,791
Burlington Water DepartmentBurlington, MA7 of 72.69 ppb25,392
Westbury WDWestbury, NY26 of 572.51 ppb20,500
Plainview WDPlainview, NY172 of 3232.14 ppb35,000
City of Corona*Corona, CA390 of 9302.04 ppb168,751
City of ColtonColton, CA109 of 2051.85 ppb46,525
Lincoln Avenue Water CompanyAltadena, CA108 of 2961.69 ppb16,126
Suburban Water Systems - San Jose HillsCovina, CA118 of 2251.66 ppb168,843
Newhall CWD-Newhall*Santa Clarita, CA18 of 451.54 ppb17,154
Golden State Water Company - West OrangeAnaheim, CA48 of 821.52 ppb113,106
Golden State WC - PlacentiaAnaheim, CA8 of 171.44 ppb49,808
Hicksville WDHicksville, NY60 of 1231.38 ppb48,000
City of WestminsterWestminster, CA29 of 621.35 ppb95,256
Redlands City*Redlands, CA583 of 1,1461.29 ppb78,025
Rockville CentreRockville Centre, NY2 of 221.29 ppb24,700
Bethpage WDBethpage, NY64 of 1981.28 ppb33,000
City of Riverside*Riverside, CA91 of 1461.27 ppb300,488
Golden State Water Company (GSWC) - Florence/GrahamSanta Fe Springs, CA132 of 3501.18 ppb62,970
City of Garden GroveGarden Grove, CA42 of 941.17 ppb174,226
City of Newman Water DepartmentNewman, CA4 of 151.12 ppb12,351
City of AnaheimAnaheim, CA43 of 911.11 ppb341,245
Valley Water Company*La Canada Flintridge, CA45 of 1341.09 ppb10,070
Garden CityGarden City, NY12 of 471.03 ppb46,000
San Fernando Water DepartmentSan Fernando, CA48 of 831.00 ppb23,946
City of ExeterExeter, CA2 of 61.000 ppb11,169
California Domestic Water Company*Whittier, CA55 of 1620.897 ppb290,814
City of Buena ParkBuena Park, CA15 of 420.886 ppb81,998
Azusa Light and WaterAzusa, CA102 of 3470.877 ppb110,044
Glen Cove CityGlen Cove, NY18 of 410.861 ppb28,000
Jurupa Community Services District*Jurupa Valley, CA73 of 2150.855 ppb133,292
Las Vegas Valley Water District*Las Vegas, NV66 of 660.825 ppb1,539,277
North Las Vegas UtilitiesLas Vegas, NV66 of 660.825 ppb376,515
Boulder City*Boulder City, NV66 of 660.825 ppb15,000
Pomona Water DepartmentPomona, CA353 of 1,1960.808 ppb151,713
City of Santa AnaSanta Ana, CA23 of 770.795 ppb337,716
Franklin Square WDFranklin Square, NY10 of 330.787 ppb20,000
Citrus Heights Water District*Citrus Heights, CA2 of 50.780 ppb66,815
San Gabriel Valley Water Company - FontanaEl Monte, CA178 of 7220.752 ppb237,300
City of ChinoChino, CA61 of 2170.736 ppb84,560
Cal/Am Water Company - San MarinoRosemead, CA7 of 370.559 ppb47,731
City of FullertonFullerton, CA8 of 350.551 ppb141,874
Monte Vista Water District*Montclair, CA75 of 3950.546 ppb56,422
Pasadena Water and Power*Pasadena, CA86 of 4340.543 ppb170,950
City of AlhambraAlhambra, CA53 of 3310.510 ppb83,750
City of ParlierParlier, CA3 of 40.500 ppb14,576
Stoughton Water Department (MWRA)*Stoughton, MA19 of 190.493 ppb26,962
Swansea Water DistrictSwansea, MA20 of 200.466 ppb17,358
City of RiverbankRiverbank, CA1 of 130.462 ppb24,834
Ontario Municipal Utilities CompanyOntario, CA80 of 2910.454 ppb185,010

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

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