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CONTAMINANT

11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)

FOUND

Exceeding guidelines

STATES DETECTED

8

serves

399,000

utilities detected

51

states detected

1

serves

10,218

utilities detected

1

Overview

11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) is a member of a group of perfluorinated chemicals used in many consumer products. 11Cl-PF3OUdS and other perfluorinated chemicals can cause serious health effects, including cancer, endocrine disruption, accelerated puberty, liver and immune system damage, and thyroid changes. These chemicals are persistent in the environment and they accumulate in people. Click here to read more about perfluorinated chemicals.

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 1 ppt

The EWG Health Guideline of 1 ppt for 11Cl-PF3OUdS was defined by EWG as based on studies by Phillipe Grandjean of Harvard University and many other independent researchers who found reduced effectiveness of vaccines and adverse impacts on mammary gland development from exposure to PFOA and PFOS, the two PFAS most widely detected in drinking water.

ppt = parts per trillion

National Standard Exists

Health Concerns:

  • Cancer

  • Harm to the immune system

  • Hormone disruption

  • Harm to fetal growth and child development

  • Harm to the liver

Want to remove
11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) from your water?

Try these filter technologies:

Activated Carbon, 

Reverse Osmosis, 

understand filter technology

11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS) around the Country

UTILITIES REPORTING ABOVE HEALTH GUIDELINES UTILITIES WITH CONTAMINATION
State Utilities People Served Utilities People Served
Massachusetts0020254,031
New York001648,266
New Jersey00146,585
Alabama110,218533,273
Louisiana0048,793
Michigan0026,304
Colorado0011,505
California002525

Utilities with the highest amounts of 11Cl-PF3OUdS, 2019-2024

ALL UTILITIES
LARGE UTILITIES
Utility Location Tests Average level People served
Lincoln, City ofLincoln, AL1 of 1211.7 ppt10,218
Ariton Water WorksAriton, AL2 of 61.80 ppt1,263
BronsonBronson, MI1 of 31.000 ppt2,421
Bells Pond Mobile Park NorthHudson, NY1 of 20.950 ppt150
Parkspace La LLC - (tp #1)Elburn, LA1 of 20.925 ppt162
Salem Water SystemFarmerville, LA1 of 20.925 ppt753
Quail Ridge Estates Water SystemLake Charles, LA1 of 20.925 ppt1,119
Hillcrest Village Mobile Home ParkWheat Ridge, CO1 of 30.867 ppt1,505
Red Creek Village*Walworth, NY1 of 50.640 ppt535
Red Creek North SaWalworth, NY1 of 50.640 ppt36
United Water CamdenCamden, NJ1 of 50.600 ppt46,585
Maillet Woods CondominiumsHopkinton, MA1 of 20.356 ppt75
Eurich HeightsWarwick, NY1 of 30.315 ppt130
Carver Municipal BuildingsCarver, MA1 of 30.281 ppt100
North Carver Water DistrictCarver, MA1 of 30.257 ppt100
Port Allen Water SystemPort Allen, LA1 of 70.250 ppt6,759
Taconic Mobile Home Park LLCThomaston, NY1 of 70.243 ppt40
Castlewood Domestic Water SystemRoseville, CA1 of 140.243 ppt524
Sfpuc-pleasanton Wells*Burlingame, CA1 of 140.243 ppt1
The Meeting House @ Stow CondoStow, MA1 of 40.239 ppt92
Taconic ShoresCopake, NY1 of 40.232 ppt950
Ormsby Mobile Home ParkPeru, NY1 of 120.118 ppt76
Guntersville Water Works and Sewer Board*Guntersville, AL1 of 170.118 ppt12,612
Pinewood On The Green CondosOxford, MA1 of 70.116 ppt50
Carmel Water District 3Mahopac, NY1 of 80.115 ppt1,600
Grove Hill Water WorksGrove Hill, AL1 of 250.108 ppt5,280
Bishops Landing CondominiumsStoughton, MA2 of 160.107 ppt64
Ardmore Water SystemArdmore, AL1 of 280.0860 ppt3,900
Candlewood Park Water DistrictNorth Salem, NY1 of 110.0840 ppt125
PortlandPortland, MI1 of 130.0770 ppt3,883
Sunset Ridge CondominiumsBolton, MA1 of 110.0710 ppt42
Rotterdam WD #5, NY2 of 290.0540 ppt28,000
Greater Plattsburgh Water District*Plattsburgh, NY1 of 150.0260 ppt12,039
Morrisonville Water DistrictPlattsburgh, NY1 of 150.0260 ppt1,300
Southeast Beekmantown Water DistrictPlattsburgh, NY1 of 150.0260 ppt400
Macey Lane Water DistrictPlattsburgh, NY1 of 150.0260 ppt135
Dartmouth Water DivisionDartmouth, MA1 of 90.0250 ppt24,272
New Bedford Department of Public Infrastructure*New Bedford, MA1 of 90.0250 ppt95,072
Acushnet Water DepartmentAcushnet, MA1 of 90.0250 ppt7,911
Enclave At BoxboroughBedford, MA1 of 290.0240 ppt100
Westborough Water DepartmentWestborough, MA1 of 650.0180 ppt18,272
North Castle Water District #5Armonk, NY1 of 520.0170 ppt225
North Castle Water District #4*Armonk, NY1 of 520.0170 ppt2,525
South Grafton Water DistrictSouth Grafton, MA1 of 410.0170 ppt3,242
Grafton Water District*Grafton, MA2 of 860.0150 ppt10,703
Dedham Westwood Water DistrictDedham, MA2 of 970.00900 ppt42,581
Groveland Water DepartmentGroveland, MA1 of 490.00800 ppt6,605
Pepperell DPW Water DivisionPepperell, MA1 of 1400.00500 ppt8,178
Littleton Water DepartmentLittleton, MA1 of 1360.00500 ppt9,182
Devens Massdevelopment*Devens, MA2 of 4980.00300 ppt6,500

* 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 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS), but it likely has the contaminant in its water supply.

UtilityLocationTestsAverage levelPeople served
Lincoln, City ofLincoln, AL1 of 1211.7 ppt10,218
United Water CamdenCamden, NJ1 of 50.600 ppt46,585
Guntersville Water Works and Sewer Board*Guntersville, AL1 of 170.118 ppt12,612
Rotterdam WD #5, NY2 of 290.0540 ppt28,000
Greater Plattsburgh Water District*Plattsburgh, NY1 of 150.0260 ppt12,039
Dartmouth Water DivisionDartmouth, MA1 of 90.0250 ppt24,272
New Bedford Department of Public Infrastructure*New Bedford, MA1 of 90.0250 ppt95,072
Westborough Water DepartmentWestborough, MA1 of 650.0180 ppt18,272
Grafton Water District*Grafton, MA2 of 860.0150 ppt10,703
Dedham Westwood Water DistrictDedham, MA2 of 970.00900 ppt42,581
Acton Water Supply DistrictActon, MA1 of 1980.00200 ppt20,890

* 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 11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS), but it likely has the contaminant in its water supply.

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