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EWG's Tap Water Database — 2019 UPDATE

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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.

2015-2017:

FOUND
FOUND ABOVE HEALTH GUIDELINES

48

states detected

24,132

utilities detected

223 million

people served

48

states over health guideline

22,003

utilities over health guideline

213 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

EWG Health Guideline 0.4 ppb

The EWG 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

States reporting chloroform in drinking water

UTILITIES REPORTING ABOVE HEALTH GUIDELINES UTILITIES WITH CONTAMINATION
State UtilitiesPeople Served UtilitiesPeople Served
California91730,581,0981,07033,905,483
Texas2,40423,998,4952,77625,010,676
New York1,33018,960,0801,39019,860,301
Illinois1,46912,602,5751,49812,687,640
Pennsylvania1,22910,185,0651,30410,302,009
Ohio9849,892,4921,0739,993,782
Georgia7388,844,1929179,128,373
North Carolina8627,493,8088797,538,961
Virginia6716,562,6737366,623,304
Massachusetts2926,233,7823246,469,249
Tennessee3285,602,3603325,860,827
Washington7094,825,8578815,521,647
New Jersey1855,011,7632145,127,269
Louisiana8284,739,2918994,909,235
Missouri6844,523,8417834,837,107
Alabama2824,409,4633324,756,622
Minnesota6103,922,1096694,112,685
Wisconsin5153,653,3715753,910,416
South Carolina3313,626,0023413,751,964
Colorado5113,702,9005443,749,124
Oklahoma6523,332,1526923,421,090
Arkansas5442,890,9355803,049,202
Connecticut2072,604,8772362,659,292
Iowa7322,439,5417512,531,934
Nevada492,427,199682,487,041
Utah1592,130,0081952,341,710
Indiana1392,217,2901382,308,807
Kansas6722,004,6947112,119,188
Mississippi5271,957,7715291,995,963
New Mexico1441,181,0192281,591,839
West Virginia3811,447,2033911,506,406
Maryland2761,307,6232841,383,665
Nebraska931,166,8341161,280,183
Delaware126892,894135938,702
New Hampshire191715,759232763,405
North Dakota280674,627286692,772
District Of Columbia4664,5724664,572
Rhode Island33588,56838612,877
Alaska170606,213173607,294
Montana205459,712222562,111
Vermont214440,877237461,878
Hawaii27135,92634424,674
Wyoming153311,525161321,418
Maine104290,259115304,031
Arizona4141,2454141,245
Kentucky10204,6858109,034
Idaho139,3311671,577
Michigan1041,416840,707
South Dakota52,77331,213
MORE
LESS

Filtering technologies that reduce chloroform

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Activated Carbon

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Reverse Osmosis

Utilities with the highest amounts of chloroform, 2015-2017

ALL UTILITIES
LARGE UTILITIES
UtilityLocationTestsAverage levelPeople served
Asher Utility Dev AuthorityAsher, OK11 of 11219.3 ppb375
Boswell Public Works AuthorityBoswell, OK18 of 18218.1 ppb932
Vixen Water System WestChatham, LA40 of 40202.4 ppb288
Thorne Bay, City ofThorne Bay, AK11 of 11194.5 ppb470
Hudson Gaars Mill Water SystemSikes, LA30 of 30185.5 ppb660
Wanette Public Works AuthorityWanette, OK11 of 11173.5 ppb402
Vixen Water System EastChatham, LA32 of 32169.7 ppb486
Fairview Union Water System*Campti, LA48 of 48167.1 ppb2,205
City of NomeNome, TX23 of 23165.9 ppb753
Osage County Rural Water District # 5Barnsdall, OK23 of 23161.5 ppb561
Osage County Rural Water District # 20 (hulah)Bartlesville, OK11 of 11160.5 ppb350
The Trails S/dChapel Hill, NC1 of 2158.0 ppb246
Stringtown Public Works AuthorityStringtown, OK20 of 20156.5 ppb1,105
Lakewood Water SystemLufkin, TX15 of 15154.9 ppb42
Severy, City ofSevery, KS12 of 12154.8 ppb241
Beechwood Water Supply CorporationHemphill, TX20 of 20154.8 ppb1,143
Sandy Point 480 Water SystemCampti, LA40 of 40150.4 ppb675
Winebrook Hills Water DistrictNewcomb, NY12 of 12145.8 ppb250
Orient Water CompanyTonasket, WA11 of 12142.3 ppb100
Csp - Big Basin State ParkFelton, CA24 of 24142.0 ppb3,029
Grayhorse Rural Water DistrictFairfax, OK12 of 12139.4 ppb100
Barnsdall*Barnsdall, OK22 of 22137.7 ppb1,243
Weleetka Public Utilities AuthorityWeleetka, OK21 of 21135.0 ppb998
Leflore County Rural Water District #3Whitesboro, OK30 of 30123.9 ppb1,643
Truelight Redevelopment GroupAnguilla, MS22 of 22122.1 ppb92
Okmulgee County Rural Water District #6 (hectorville)Mounds, OK23 of 23121.2 ppb8,370
Warren County Water SystemWarrenton, GA24 of 24120.3 ppb300
Elmdale, City ofElmdale, KS1 of 1120.0 ppb53
PittsburgPittsburg, OK12 of 12118.6 ppb280
Vanderheyden Hall Inc.Wynantskill, NY1 of 1118.0 ppb280
Ryan Utilities AuthorityRyan, OK23 of 23115.3 ppb800
Anthony Harbor SubdivisionLufkin, TX15 of 15113.7 ppb109
Seminole County Rural Water District #1Wewoka, OK12 of 12113.6 ppb387
Latimer County Rural Water District #3Wister, OK5 of 5112.3 ppb175
Cloverhill 3 - Consecutive To Md0100015Frederick, MD2 of 2111.8 ppb888
Carthage, Town ofCarthage, NC24 of 24111.3 ppb2,767
Lake City Water Association-westYazoo City, MS1 of 1111.0 ppb950
East Columbia Water SystemColumbia, LA16 of 16108.4 ppb2,640
Central Yazoo #4-bentonYazoo City, MS1 of 1107.0 ppb1,083
Elk City, City ofElk City, KS13 of 13106.7 ppb314
Okmulgee County Rural Water District #1Schulter, OK23 of 23106.6 ppb1,890
Sa#16 Sumner Hill-water SystemMadera, CA12 of 12106.6 ppb128
Mccurtain County Rural Water District #6 (kiamichi)Smithville, OK18 of 18105.8 ppb600
Talihina PWA*Talihina, OK24 of 24103.7 ppb1,297
Rye, Town ofRye, CO3 of 3103.6 ppb244
Otoe-missouria TribeRed Rock, OK13 of 14101.5 ppb250
Cleveland Municipal AuthorityCleveland, OK35 of 35101.2 ppb3,262
Atoka County Rural Water District #1 (wardville)Kiowa, OK12 of 12100.8 ppb125
Choctaw County Rural Water System & Solid Waste Management District #6*Boswell, OK17 of 21100.0 ppb850
Mccurtain Municipal AuthorityMccurtain, OK24 of 2499.7 ppb560

* 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.

UtilityLocationTestsAverage levelPeople served
Union CityUnion City, GA4 of 477.3 ppb18,636
Walnut Creek SUD*Springtown, TX51 of 5176.6 ppb23,807
Duncan Public Utilities Authority*Duncan, OK48 of 4972.5 ppb23,000
Claremore*Claremore, OK53 of 5372.0 ppb15,873
East ProvidenceEast Providence, RI12 of 1268.6 ppb48,688
South Granville Water and Sewer AuthorityButner, NC51 of 5164.7 ppb19,219
Washington Water Authority WWAFarmington, AR48 of 4862.1 ppb15,734
East Longmeadow DPW Water DepartmentEast Longmeadow, MA48 of 4861.4 ppb16,162
Okmulgee*Okmulgee, OK49 of 4961.4 ppb13,495
Buchanan County PSA*Vansant, VA48 of 4860.4 ppb19,205
Southwest Ouachita Waterworks Inc.West Monroe, LA40 of 4259.5 ppb10,092
Eatonton Putnam Water & Sewer AuthorityEatonton, GA24 of 2456.7 ppb12,561
Harrisburg*Harrisburg, NC48 of 4856.4 ppb14,633
Floyd Water District*Rome, NY12 of 1256.3 ppb34,560
El Dorado ID - Main*Placerville, CA98 of 10155.3 ppb112,000
James Fork Regional Water District*Greenwood, AR51 of 5155.1 ppb11,380
Barrow County Water System*Winder, GA28 of 2854.4 ppb14,043
Quantico Marine Base-Mainside*Quantico, VA48 of 4854.0 ppb14,525
City of Conover*Conover, NC48 of 4854.0 ppb14,554
US Air Force AcademyUsaf Academy, CO28 of 2853.6 ppb16,876
Valdosta*Valdosta, GA49 of 4953.5 ppb51,769
City of Troy Public Utilities*Troy, NY4 of 453.4 ppb117,581
Guilderland Town WDGuilderland, NY48 of 4853.3 ppb30,000
City of Paris*Paris, TX51 of 5153.0 ppb25,498
Assumption Parish Waterworks District 1*Napoleonville, LA96 of 9653.0 ppb22,862
East Greenbush General WD*Rensselaer, NY40 of 4052.8 ppb10,200
Lincoln Water CommissionLincoln, RI44 of 4852.3 ppb21,137
Watertown City*Watertown, NY145 of 14752.2 ppb29,406
Warren City PWS*Cortland, OH48 of 4852.1 ppb46,832
College Utilities Corporation*Fairbanks, AK48 of 4851.9 ppb27,000
Tri County Joint Municipal Authority*Fredericktown, PA48 of 4851.8 ppb10,100
Wvaw - Weston*Weston, WV36 of 3651.8 ppb13,026
Newark Village*Shortsville, NY24 of 2451.2 ppb20,762
Mohawk Correctional Facility*Rome, NY12 of 1251.2 ppb34,775
Laconia Water Works*Belmont, NH35 of 3551.1 ppb15,500
Halfmoon Water District (Troy)*Halfmoon, NY60 of 6050.9 ppb14,599
Bella Vista POABella Vista, AR48 of 4850.9 ppb26,461
Exeter Water DepartmentExeter, NH42 of 4250.9 ppb11,000
Lamar County Water Supply District*Paris, TX48 of 4850.6 ppb22,269
City of Walhalla*Walhalla, SC48 of 4850.6 ppb15,740
Rogers County Rural Water District # 3 Lake PlantClaremore, OK25 of 2550.5 ppb10,470
Monroeville Municipal Authority*Monroeville, PA101 of 10150.3 ppb48,500
City Corporation*Russellville, AR48 of 4850.1 ppb28,616
Galion CityGalion, OH48 of 4850.1 ppb10,175
Jackson County Water & Sewer Authority*Jefferson, GA48 of 4849.6 ppb19,191
CCWD Ebbetts Pass Improvement District*San Andreas, CA49 of 4949.4 ppb14,340
Richmond County Water System*Rockingham, NC52 of 5249.4 ppb25,410
Bedford Regional Water Authority (brwa)Bedford, VA43 of 4349.2 ppb30,133
Dartmouth Water DivisionDartmouth, MA54 of 5449.1 ppb24,081
Pickens Water Treatment Plant*Pickens, SC36 of 3648.4 ppb10,871

* 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.