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National Drinking Water Database


National Drinking Water Database - Chemical Contaminants

Chlorite


Status: Regulated - EPA has established a maximum legal limit in tapwater for this contaminant.

Chlorite is a disinfection byproduct resulting from water treatment with chlorine dioxide, or from the use of chlorine dioxide as a bleaching agent for cellulose, paper pulp, flour and oils. [read more]

 
Detected
Found above
health guidelines
Found above
legal limit
States
22
7
5
Water utilities
113
23
7
People Served
3,957,125
405,670
184,594

Health Concerns for Chlorite:


Chlorite Exposure by State

Water utilities in 22 states have reported detecting Chlorite in treated tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies.

StateWater Suppliers with Chlorite contaminationWater suppliers reporting Chlorite above health-based limits
SystemsPopulationSystemsPopulation
North Carolina5172,9763160,545
Kentucky7133,396397,401
California7509,750153,550
Missouri2196,939634,795
Iowa12134,923630,956
Massachusetts9433,553116,348
Illinois10130,930312,075
Arizona3616,00000
Virginia9536,06600
Alabama3524,01000
Florida2233,20300
Arkansas785,89400
New Jersey283,99400
New York380,57800
Washington165,00000
Wyoming258,67200
Nebraska121,60000
Ohio115,64100
Minnesota211,55100
New Mexico410,53400
Maine11,87000
Oregon14500
Total1133,957,12523405,670

The Most Polluted Communities

113 water utilities reported detecting Chlorite in tap water since 2004, according to EWG's analysis of water quality data supplied by state water agencies

Ranked by highest average Chlorite level

RankSystem Population Served Positive test results of total reported tests Average Level
(Range)
1Brunswick County Water System
Leland, NC
72,94750 of 50735.47 ppb
(376.67 to 1016.67 ppb)
2Paducah Water Works
Paducah, KY
47,00025 of 25626.41 ppb
(20 to 909.5 ppb)
3Rend Lake Inter-City Water System
Benton, IL
2,92838 of 38582.5 ppb
(108.33 to 993.33 ppb)
4Lamoni Municipal Utilities
Lamoni, IA
2,55464 of 66581.92 ppb
(0 to 1033.33 ppb)
5Carlinville
Carlinville, IL
5,68513 of 13578.21 ppb
(350 to 980 ppb)
6Cameron
Cameron, MO
9,78847 of 47570.21 ppb
(283.33 to 803.33 ppb)
7Kinkaid Area Water System
Murphysboro, IL
113 of 13550.57 ppb
(0.75 to 776.67 ppb)
8City of Escondido
Escondido, CA
140,0001 of 1550 ppb
(550 ppb)
9Osceola Water Works
Osceola, IA
4,65930 of 31548.92 ppb
(0 to 970 ppb)
10Hamilton
Hamilton, MO
1,75047 of 47545.18 ppb
(50 to 910 ppb)

Health Based Limits for Chlorite

StandardDescriptionLevel
Maximum Contaminant Limit Goal (MCLG)A non-enforceable health goal that is set at a level at which no known or anticipated adverse effect on the health of persons occurs and which allows an adequate margin of safety. Source: U.S. Environmental Protection Agency.800 ppb
Lifetime health-based limit, non-cancer riskConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for a lifetime of exposure. The Lifetime health-based limit (or Health Advisory, HA) is based on exposure for a a 70-kg adult consuming 2 liters of water per day. Source: U.S. Environmental Protection Agency.800 ppb
Children's health-based limit for 1-day exposureConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic health effects for up to one day of exposure. The One-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.840 ppb
Children's health-based limit for 10-day exposureConcentration of a chemical in drinking water that is not expected to cause any adverse, noncarcinogenic effects for up to ten days of exposure. The Ten-Day health-based limit (or Health Advisory, HA) is typically set to protect a 10-kg child consuming 1 liter of water per day. Source: U.S. Environmental Protection Agency.840 ppb
Maximum Contaminant Limit (MCL)The enforceable standard which defines the highest level of a contaminant that is allowed in drinking water. MCLs are set as close to health-based limits (Maximum Contaminant Level Goals, or MCLGs) as feasible using the best available analytical and treatment technologies and taking cost into consideration. Source: U.S. Environmental Protection Agency.1000 ppb
Drinking Water Equivalent LevelA lifetime exposure concentration protective of adverse, noncarcinogenic health effects, that assumes all of the exposure to a contaminant is from drinking water. Source: U.S. Environmental Protection Agency.1000 ppb

Testing Summary for Chlorite

Are tests routinely required for Chlorite by federal law?Yes
Water suppliers reporting tests for Chlorite (2004-2009):161 of 47,576
Average testing rate for water supplier reporting tests (2004-2009):4.6 per year

Violation Summary for Chlorite

Data from the U.S. Environmental Protection Agency includes the following violations of federal standards for Chlorite since 2004

Maximum Contaminant Level Exceedance Violations18
Monitoring Violations0
Reporting Violations0

Cancer

Type of concern: Reference:
Mutagen - limited evidence EPA Water Disinfection By-Products Carcinogenicity



Government, industry, academic studies and classifications

government/industry list/academic study appears on list as classification(s)
EPA Water Disinfection By-Products CarcinogenicityCHLORITE•Low to moderate concern for potential carcinogenicity



references

government/industry list/academic study reference
EPA Water Disinfection By-Products CarcinogenicityEPA (U.S. Environmental Protection Agency). 2006. EPA Water Disinfection By-Products with Carcinogenicity Estimates. Last updated: 10 April 2006.

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