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CONTAMINANT

4:2 Fluorotelomer sulfonate (4:2 FTS)

STATES DETECTED

4

serves

222,000

utilities detected

16

states detected

0

serves

0

utilities detected

0

Overview

4:2 Fluorotelomer sulfonate (4:2 FTS) is a member of a class of chemicals called per- and polyfluoroalkyl substances or PFAS. These chemicals were used in the production of non-stick, stain repellent and chemically inert coatings. 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 4:2 fluorotelomer sulfonate (4:2 FTS) was defined by EWG 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
4:2 Fluorotelomer sulfonate (4:2 FTS) from your water?

Try these filter technologies:

Activated Carbon, 

Reverse Osmosis, 

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4:2 Fluorotelomer sulfonate (4:2 FTS) around the Country

UTILITIES WITH CONTAMINATION
State Utilities People Served
Iowa299,834
New York1192,107
Rhode Island225,500
Utah14,106

Utilities with the highest amounts of 4:2 fluorotelomer sulfonate (4:2 FTS), 2021-2023

ALL UTILITIES
LARGE UTILITIES
Utility Location Tests Average level People served
Shady Harbor Fire DistrictWestwood, RI8 of 101.04 ppt300
Woods At Kings Pond Condo W.s.Croton Falls, NY2 of 20.992 ppt96
Bells Pond Mobile Park NorthHudson, NY1 of 20.950 ppt150
Sioux City Water Supply*Sioux City, IA4 of 80.875 ppt85,791
City of South Sioux CitySouth Sioux City, NE4 of 80.875 ppt14,043
Adirondack Airport CommunitySaranac Lake, NY2 of 70.829 ppt90
Scotia Village Water WorksScotia, NY1 of 210.510 ppt12,800
North Kingstown*North Kingstown, RI4 of 130.337 ppt25,200
Charlton Water District (glenville)Charlton, NY1 of 190.268 ppt2,000
Glenville Water District #11*, NY1 of 190.268 ppt63,776
Taconic Mobile Home Park LLCThomaston, NY1 of 70.243 ppt40
Taconic ShoresCopake, NY1 of 40.232 ppt950
Wilton Water & Sewer AuthorityGansevoort, NY2 of 50.210 ppt9,375
Sands PointPort Washington, NY2 of 300.160 ppt2,800
Pomona Country ClubSuffern, NY1 of 130.0900 ppt30
Twin Creeks Special Service DistrictPayson, UT1 of 390.01000 ppt4,106

* 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 4:2 Fluorotelomer sulfonate (4:2 FTS), but it likely has the contaminant in its water supply.

UtilityLocationTestsAverage levelPeople served
Sioux City Water Supply*Sioux City, IA4 of 80.875 ppt85,791
City of South Sioux CitySouth Sioux City, NE4 of 80.875 ppt14,043
Scotia Village Water WorksScotia, NY1 of 210.510 ppt12,800
North Kingstown*North Kingstown, RI4 of 130.337 ppt25,200
Glenville Water District #11*, NY1 of 190.268 ppt63,776

* 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 4:2 Fluorotelomer sulfonate (4:2 FTS), but it likely has the contaminant in its water supply.

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