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Chloroform

Status: No national drinking water standard exists

 

Chloroform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Chloroform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Read More.

In addition to tap water disinfection, chloroform pollution in the environment also comes from industrial discharges from pulp and paper mills, and from urban wastewater effluent. Human studies show that chloroform damages the kidneys, liver and central nervous system. In animals, chloroform causes infertility, birth defects and cancer.

Click here to read more about disinfection byproducts.

2015:

FOUND
FOUND ABOVE HEALTH GUIDELINES

44

states detected

18,482

utilities detected

213 million

people served

44

states over health guideline

17,820

utilities over health guideline

206 million

people served over health guideline

Health concerns for chloroform

Cancer

Harm to fetal growth and development

State and national drinking water standards and health guidelines

Health Guideline 0.4 ppb

The health guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

ppb = parts per billion.

EPA Maximum Contaminant
Level Goal (MCLG)70.0 ppb

A non-enforceable federal health guideline. For cancer-causing chemicals, these health goals are typically set to zero.

ppb = parts per billion.

States reporting chloroform in drinking water

UTILITIES REPORTING ABOVE HEALTH GUIDELINES UTILITIES WITH CONTAMINATION
State UtilitiesPeople Served UtilitiesPeople Served
California75531,267,30182234,136,827
Texas2,14122,913,6202,22623,358,241
New York95018,171,70897618,758,030
Illinois1,21812,515,9411,22012,524,518
Ohio9699,951,08398710,012,105
Pennsylvania9929,777,7001,0159,840,072
Massachusetts2798,857,9232888,973,580
Georgia5747,892,8686168,005,955
North Carolina6897,463,0126897,463,012
Virginia4836,326,6844946,336,264
Tennessee2855,284,8002905,409,265
Washington5315,115,7375895,376,915
New Jersey2355,006,3322825,223,287
Missouri5844,428,5076184,561,288
Alabama2404,161,8132564,271,739
Minnesota5203,882,1545453,954,922
Louisiana6853,836,4406963,888,903
Wisconsin3663,481,7504053,711,920
South Carolina2813,399,1412863,455,512
Colorado4013,379,3054063,390,149
Oklahoma7313,305,5807363,315,907
Arkansas5242,900,6735473,034,317
Maryland1402,675,1461452,973,428
Connecticut1822,605,3251932,639,840
Nevada392,390,401442,432,639
Iowa5432,357,0875442,382,293
Kansas5592,118,2775652,176,679
Indiana992,042,3761002,050,376
New Mexico1241,175,0431701,468,912
West Virginia3531,406,6853591,453,891
Delaware89819,08095875,846
Mississippi207873,698207873,698
District Of Columbia4664,5724664,572
New Hampshire104555,790108614,170
North Dakota262594,052263609,479
Alaska131577,687132578,434
Montana156438,406160517,345
Rhode Island30452,37731490,377
Vermont155419,648159423,364
Wyoming116304,732116304,732
Hawaii18119,70221217,721
Maine62194,67863194,788
Kentucky8126,5018126,501
Michigan335,378335,378
South Dakota31,21331,213
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Utilities with the highest amounts of chloroform, 2015

ALL UTILITIES
LARGE UTILITIES
UtilityLocationTestsAverage levelPeople served
Winebrook Hills Water DistrictNewcomb, NY4 of 4191.0 ppb250
Mccurtain County Rural Water District #6 (kiamichi)Smithville, OK2 of 2191.0 ppb2,000
Thorne Bay, City ofThorne Bay, AK3 of 3181.3 ppb775
Vixen Water System EastWest Monroe, LA2 of 2168.0 ppb486
Vixen Water System WestWest Monroe, LA6 of 6160.8 ppb288
Fairview Union Water System*Campti, LA5 of 5157.3 ppb2,205
Hidden Oaks Subdivision WsMonroe, LA4 of 4153.8 ppb315
Asher Utility Dev AuthorityAsher, OK3 of 3149.3 ppb375
Weleetka Public Utilities AuthorityWeleetka, OK5 of 5149.0 ppb1,014
Boswell Public Works AuthorityBoswell, OK4 of 4149.0 ppb932
Wanette Public Works AuthorityWanette, OK4 of 4147.5 ppb402
Westwind Mobile Home ParkLake Oswego, CA1 of 1145.8 ppb104
Loring Development AuthorityLimestone, ME4 of 4144.8 ppb215
Csp - Big Basin State ParkFelton, CA8 of 8143.3 ppb3,029
Kiamichi Baptist AssemblyTalihina, OK4 of 4142.3 ppb50
Orient Water CompanyTonasket, WA3 of 3140.7 ppb100
Pecan Lake Subdivision WsMonroe, LA4 of 4138.5 ppb57
City Of MontagueMontague, CA1 of 1138.0 ppb1,495
Hudson Gaars Mill Water SystemSikes, LA2 of 2134.5 ppb660
Lakewood Water SystemLufkin, TX5 of 5134.5 ppb52
Hcwsd-unionvale-kenwood Public Water SystemCadiz, OH3 of 3133.2 ppb504
Osage County Rural Water District # 5Barnsdall, OK7 of 7132.0 ppb561
Lake Jackson Water AssociationGreenville, MS7 of 7131.5 ppb681
Montgomery County Rural Water District 13Sedan, KS4 of 4131.0 ppb160
Oklahoma Veterans CenterTalihina, OK4 of 4128.6 ppb175
Buckland Water SystemBuckland, AK4 of 4125.3 ppb417
Severy, City ofSevery, KS2 of 2125.0 ppb241
Coffey*Coffey, MO2 of 2124.5 ppb85
Milford, City ofMilford, KS4 of 4124.3 ppb594
Deering Utility SystemDeering, AK1 of 1123.0 ppb150

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

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UtilityLocationTestsAverage levelPeople served
Central Elmore Water Authority*Wetumpka, AL1 of 199.8 ppb32,877
Walnut Creek SUD*Springtown, TX17 of 1784.6 ppb18,528
Claremore*Claremore, OK16 of 1682.9 ppb15,873
Washington Water Authority WWAFarmington, AR16 of 1674.1 ppb15,734
Benton - Washington Regional Public Water Authority*Rogers, AR7 of 772.5 ppb77,085
Mt Werner WD*Steamboat Springs, CO7 of 770.2 ppb16,980
Duncan Public Utilities Authority*Duncan, OK16 of 1669.7 ppb23,000
South Granville Water and Sewer AuthorityButner, NC17 of 1769.4 ppb19,219
Fort Carson Army BaseFort Carson, CO12 of 1267.9 ppb42,000
Ardmore*Ardmore, OK16 of 1666.1 ppb24,283
Monroeville Municipal Authority*Monroeville, PA64 of 6464.7 ppb48,500
East Longmeadow DPW Water DepartmentEast Longmeadow, MA16 of 1664.2 ppb15,554
Buchanan County PSA*Vansant, VA16 of 1663.3 ppb18,689
US Air Force AcademyUsaf Academy, CO4 of 462.6 ppb16,876
James Fork Regional Water District*Greenwood, AR17 of 1762.2 ppb11,380
Barrow County Water System*Winder, GA8 of 861.3 ppb13,260
Centerton WaterworksCenterton, AR16 of 1660.1 ppb13,235
City of Paris*Paris, TX17 of 1759.8 ppb30,993
Bella Vista POA*Bella Vista, AR16 of 1659.3 ppb26,461
Marshall County Water Corp*Madill, OK17 of 1758.1 ppb14,717
Poplar BluffPoplar Bluff, MO17 of 1757.8 ppb17,000
Youngstown City Public Water System*Youngstown, OH33 of 3357.2 ppb148,000
El Dorado ID - Main*Placerville, CA33 of 3356.8 ppb112,000
Monroe Water System*Monroe, WA12 of 1256.3 ppb18,513
Texarkana Water Utilities*Texarkana, AR17 of 1756.3 ppb32,097
Neenah WaterworksNeenah, WI16 of 1656.2 ppb25,892
Harrisburg*Harrisburg, NC16 of 1656.0 ppb14,633
Left Hand WD*Niwot, CO10 of 1056.0 ppb18,778
City of Bloomington Utilities*Bloomington, IN1 of 156.0 ppb63,580
City of Walhalla*Walhalla, SC16 of 1655.3 ppb15,415

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

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