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CONTAMINANT

9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS)

FOUND

Exceeding guidelines

STATES DETECTED

9

serves

130,000

utilities detected

42

states detected

1

serves

10,218

utilities detected

1

Overview

9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) is a member of a group of perfluorinated chemicals used in many consumer products. 9Cl-PF3ONS 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 9Cl-PF3ONS 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
9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) from your water?

Try these filter technologies:

Activated Carbon, 

Reverse Osmosis, 

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9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) around the Country

UTILITIES REPORTING ABOVE HEALTH GUIDELINES UTILITIES WITH CONTAMINATION
State Utilities People Served Utilities People Served
Massachusetts00432,707
Oklahoma00632,470
Alabama110,218527,909
New York001721,176
Louisiana0048,793
Michigan0013,883
Colorado0022,127
California002525
Wisconsin001500

Utilities with the highest amounts of 9Cl-PF3ONS, 2019-2024

ALL UTILITIES
LARGE UTILITIES
Utility Location Tests Average level People served
Lincoln, City ofLincoln, AL1 of 1211.7 ppt10,218
Ponca City Mun Water*Ponca City, OK1 of 31.13 ppt27,155
Kay County Rural Water District #3Ponca City, OK1 of 31.13 ppt1,000
Osage County Rural Water System & Solid Waste District #3 (braden)*Ponca City, OK1 of 31.13 ppt700
Mccord Rural Water District #3Ponca City, OK1 of 31.13 ppt1,800
Kay County Rural Water District #1Ponca City, OK1 of 31.13 ppt1,765
Kay County Rural Water District #2Marland, OK1 of 31.13 ppt50
Bells Pond Mobile Park NorthHudson, NY1 of 20.950 ppt150
Parkspace La LLC - (tp #1)Elburn, LA1 of 20.925 ppt162
Quail Ridge Estates Water SystemLake Charles, LA1 of 20.925 ppt1,119
Salem Water SystemFarmerville, LA1 of 20.925 ppt753
Hillcrest Village Mobile Home ParkWheat Ridge, CO1 of 30.900 ppt1,505
Ariton Water WorksAriton, AL1 of 60.667 ppt1,263
Red Creek North SaWalworth, NY1 of 50.620 ppt36
Red Creek Village*Walworth, NY1 of 50.620 ppt535
Satsuma Water WorksSatsuma, AL1 of 120.358 ppt7,248
Three Lakes Sanitary DistrictThree Lakes, WI1 of 20.330 ppt500
Port Allen Water SystemPort Allen, LA1 of 70.250 ppt6,759
Castlewood Domestic Water SystemRoseville, CA1 of 140.243 ppt524
Sfpuc-pleasanton Wells*Burlingame, CA1 of 140.243 ppt1
Taconic Mobile Home Park LLCThomaston, NY1 of 70.243 ppt40
Carmel Water District 6-shell ValleyMahopac, NY1 of 40.241 ppt324
Taconic ShoresCopake, NY1 of 40.232 ppt950
Carmel Water District 3Mahopac, NY1 of 80.115 ppt1,600
Grove Hill Water WorksGrove Hill, AL1 of 250.108 ppt5,280
Ardmore Water SystemArdmore, AL1 of 280.0930 ppt3,900
Macey Lane Water DistrictPlattsburgh, NY1 of 150.0850 ppt135
Southeast Beekmantown Water DistrictPlattsburgh, NY1 of 150.0850 ppt400
Greater Plattsburgh Water District*Plattsburgh, NY1 of 150.0850 ppt12,039
Morrisonville Water DistrictPlattsburgh, NY1 of 150.0850 ppt1,300
Candlewood Park Water DistrictNorth Salem, NY1 of 110.0840 ppt125
PortlandPortland, MI1 of 130.0770 ppt3,883
Valkill East Mobile Home ParkWappingers Falls, NY1 of 110.0720 ppt300
RiverbridgeBrewster, MA1 of 150.0700 ppt1,330
Ormsby Mobile Home ParkPeru, NY1 of 120.0580 ppt76
Maple Grove West Mobile Home ParkNorwich, NY1 of 150.0520 ppt416
Eads, Town ofEads, CO1 of 80.0380 ppt622
North Castle Water District #5Armonk, NY1 of 520.0210 ppt225
North Castle Water District #4*Armonk, NY1 of 520.0210 ppt2,525
Westborough Water DepartmentWestborough, MA1 of 650.0180 ppt18,272
Groveland Water DepartmentGroveland, MA1 of 490.00800 ppt6,605
Devens Massdevelopment*Devens, MA1 of 4980.00200 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 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) , but it likely has the contaminant in its water supply.

UtilityLocationTestsAverage levelPeople served
Lincoln, City ofLincoln, AL1 of 1211.7 ppt10,218
Ponca City Mun Water*Ponca City, OK1 of 31.13 ppt27,155
Greater Plattsburgh Water District*Plattsburgh, NY1 of 150.0850 ppt12,039
Westborough Water DepartmentWestborough, MA1 of 650.0180 ppt18,272

* 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 9-chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS) , but it likely has the contaminant in its water supply.

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