Perfluorooctane sulfonate (PFOS)
Status: No national drinking water standard exists
Perfluorooctane sulfonate (PFOS) is a member of a group of perfluorinated chemicals used in many consumer products. PFOS 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.
2013-2019:
28
states detected
928
utilities detected
28 million
people served
27
states over health guideline
646
utilities over health guideline
19 million
people served over health guideline
Health concerns for PFOS
Cancer
Harm to the immune system
Hormone disruption
Harm to fetal growth and child development
Harm to the liver
State and national drinking water standards and health guidelines
EWG Health Guideline 1 ppt
The EWG Health Guideline of 1 ppt for PFOS 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. This health guideline applies to the entire class of PFAS detected in water.
EPA Proposed Maximum Contaminant
Level (MCL) 4 ppt
The proposed legal limit for PFOS is 4 ppt, based on studies on people, including children, showing cancer risk.
ppt = parts per trillion
States reporting PFOS in drinking water
| UTILITIES REPORTING ABOVE HEALTH GUIDELINES | UTILITIES WITH CONTAMINATION | ||||||
|---|---|---|---|---|---|---|---|
| State | Utilities | People Served | Utilities | People Served | |||
| California | 84 | 5,484,489 | 121 | 8,175,377 | |||
| North Carolina | 113 | 2,142,515 | 230 | 5,590,825 | |||
| New Jersey | 164 | 3,223,441 | 202 | 3,603,498 | |||
| Florida | 26 | 3,179,461 | 26 | 3,179,461 | |||
| New York | 23 | 1,425,905 | 42 | 1,829,617 | |||
| Kentucky | 28 | 168,917 | 61 | 1,746,482 | |||
| Massachusetts | 21 | 360,184 | 27 | 563,453 | |||
| Ohio | 8 | 349,931 | 8 | 349,931 | |||
| Rhode Island | 13 | 208,405 | 19 | 337,851 | |||
| New Hampshire | 79 | 195,167 | 93 | 336,388 | |||
| Delaware | 2 | 307,000 | 2 | 307,000 | |||
| Alabama | 22 | 299,280 | 22 | 299,280 | |||
| Wisconsin | 1 | 53,000 | 6 | 291,297 | |||
| Arizona | 6 | 271,761 | 6 | 271,761 | |||
| Michigan | 9 | 241,162 | 9 | 241,162 | |||
| Pennsylvania | 7 | 215,484 | 7 | 215,484 | |||
| Texas | 17 | 178,168 | 15 | 176,965 | |||
| Alaska | 4 | 29,349 | 11 | 144,398 | |||
| Minnesota | 2 | 43,777 | 3 | 115,777 | |||
| Georgia | 3 | 75,208 | 3 | 75,208 | |||
| Colorado | 3 | 70,414 | 3 | 70,414 | |||
| Maine | 4 | 48,587 | 4 | 48,587 | |||
| Washington | 1 | 32,603 | 1 | 32,603 | |||
| Illinois | 2 | 26,598 | 2 | 26,598 | |||
| Indiana | 1 | 16,800 | 1 | 16,800 | |||
| West Virginia | 1 | 15,652 | 1 | 15,652 | |||
| South Carolina | 0 | 0 | 1 | 6,623 | |||
| Tennessee | 2 | 3,352 | 2 | 3,352 | |||
Filtering technologies that reduce PFOS
Activated Carbon
Reverse Osmosis
Utilities with the highest amounts of PFOS, 2013-2019
| Utility | Location | Tests | Average level | People served |
|---|---|---|---|---|
| Eielson - Air Force Base | Eielson Afb, AK | 2 of 4 | 762.5 ppt | 8,193 |
| Hoosick Falls | Hoosick Falls, NY | 12 of 27 | 356.5 ppt | 4,925 |
| Carle Place Water District | Carle Place, NY | 1 of 7 | 300.0 ppt | 9,005 |
| Pawling Village* | Pawling, NY | 4 of 16 | 270.8 ppt | 2,200 |
| Pawling Water District #1 | Pawling, NY | 4 of 16 | 270.8 ppt | 100 |
| Oatman Water Company | Scottsdale, AZ | 2 of 2 | 265.0 ppt | 280 |
| Horsham Water&sewer Authority | Horsham, PA | 123 of 180 | 208.8 ppt | 25,000 |
| Delilah Terrace Mobile Home Park | Pittsford, NJ | 5 of 5 | 208.0 ppt | 210 |
| Sussex County Hlth-the Homested | Newton Town, NJ | 4 of 4 | 170.0 ppt | 100 |
| Security Waster District | Colorado Springs, CO | 35 of 38 | 169.7 ppt | 19,000 |
| City of Stuart - Water Plant | Stuart, FL | 2 of 2 | 160.0 ppt | 19,000 |
| Issaquah Water System | Issaquah, WA | 3 of 9 | 158.8 ppt | 32,603 |
| Newburgh City | Newburgh, NY | 4 of 4 | 150.0 ppt | 28,000 |
| Oakdale* | Oakdale, MN | 56 of 119 | 115.8 ppt | 28,315 |
| Rome* | Rome, GA | 4 of 4 | 95.0 ppt | 45,586 |
| Wright-Patterson AFB Area A PWS | Wright Patterson Afb, OH | 4 of 8 | 85.0 ppt | 16,551 |
| Oakland Association Inc. | Oakland, RI | 3 of 3 | 81.5 ppt | 175 |
| Warminster Municipal Authority* | Warminster, PA | 10 of 38 | 72.8 ppt | 40,000 |
| Houlton Mobile Home Park | Houlton, ME | 1 of 1 | 70.6 ppt | 140 |
| Passaic Valley Water Commission-postbrook | Clifton, NJ | 24 of 24 | 54.3 ppt | 458 |
| New Lisbon Development Center | New Lisbon, NJ | 5 of 5 | 52.5 ppt | 2,014 |
| Hyannis Water System | Hyannis, MA | 28 of 44 | 50.6 ppt | 35,000 |
| Ocala Palms (consec.) | Ocala, FL | 2 of 2 | 50.5 ppt | 2,015 |
| City of Ocala* | Ocala, FL | 2 of 2 | 50.5 ppt | 57,665 |
| City of North Miami* | North Miami, FL | 3 of 3 | 50.3 ppt | 88,349 |
| Artesian Water Company* | Newark, DE | 5 of 61 | 49.9 ppt | 301,000 |
| FKAA J. Robert Dean Water Treatment Plant | Florida City, FL | 2 of 2 | 48.5 ppt | 86,000 |
| Warrington Twp Water&sew Dept | Warrington, PA | 3 of 17 | 48.4 ppt | 21,588 |
| Town Creek Water System | Town Creek, AL | 2 of 4 | 45.0 ppt | 1,635 |
| West Morgan-East Lawrence Water Authority* | Decatur, AL | 2 of 4 | 45.0 ppt | 30,000 |
| Montebello Land & Water Company | Montebello, CA | 32 of 34 | 42.6 ppt | 32,219 |
| United Water Pennsylvania | Harrisburg, PA | 1 of 9 | 40.3 ppt | 110,000 |
| Addison Water Works | Addision, AL | 4 of 8 | 40.0 ppt | 2,553 |
| V.A.W. Water System, Inc* | Holly Pond, AL | 4 of 8 | 40.0 ppt | 15,582 |
| Cal-water Service Company-oroville | Chico, CA | 15 of 17 | 39.3 ppt | 9,427 |
| Commerce-city, Water Department | San Jose, CA | 2 of 2 | 38.5 ppt | 3,828 |
| La Habra Heights County Water District* | La Habra Heights, CA | 15 of 15 | 36.6 ppt | 5,379 |
| Barrow Utilities & Elec. Co-op Inc. (bu* | Barrow, AK | 8 of 16 | 36.4 ppt | 4,850 |
| The Water Service | Barrow, AK | 8 of 16 | 36.4 ppt | 438 |
| Northeast Etowah County Water Co-op | Gadsden, AL | 3 of 4 | 35.0 ppt | 4,164 |
| Highland Water Authority | Gadsden, AL | 3 of 4 | 35.0 ppt | 3,852 |
| Gadsden Water Works and Sewer Board* | Gadsden, AL | 3 of 4 | 35.0 ppt | 44,637 |
| Whorton Bend Water Authority | Gadsden, AL | 3 of 4 | 35.0 ppt | 2,301 |
| Yorba Linda Water District | Yorba Linda, CA | 99 of 103 | 34.7 ppt | 77,513 |
| Widefield WSD* | Colorado Springs, CO | 6 of 17 | 34.6 ppt | 22,414 |
| Liberty Water Lpsco* | Avondale, AZ | 2 of 12 | 34.2 ppt | 50,045 |
| Sanford Water District | Sanford, ME | 2 of 16 | 33.8 ppt | 14,025 |
| Camp Pendleton (South) | Camp Pendleton, CA | 93 of 274 | 33.4 ppt | 39,400 |
| Liberty Utilities - Bellflower - Norwalk | Downey, CA | 14 of 22 | 33.1 ppt | 72,884 |
| Montebello-city, Water Department | El Monte, CA | 4 of 4 | 33.0 ppt | 6,962 |
* 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 Perfluorooctane sulfonate (PFOS), but it likely has the contaminant in its water supply.
| Utility | Location | Tests | Average level | People served |
|---|---|---|---|---|
| Horsham Water&sewer Authority | Horsham, PA | 123 of 180 | 208.8 ppt | 25,000 |
| Security Waster District | Colorado Springs, CO | 35 of 38 | 169.7 ppt | 19,000 |
| City of Stuart - Water Plant | Stuart, FL | 2 of 2 | 160.0 ppt | 19,000 |
| Issaquah Water System | Issaquah, WA | 3 of 9 | 158.8 ppt | 32,603 |
| Newburgh City | Newburgh, NY | 4 of 4 | 150.0 ppt | 28,000 |
| Oakdale* | Oakdale, MN | 56 of 119 | 115.8 ppt | 28,315 |
| Rome* | Rome, GA | 4 of 4 | 95.0 ppt | 45,586 |
| Wright-Patterson AFB Area A PWS | Wright Patterson Afb, OH | 4 of 8 | 85.0 ppt | 16,551 |
| Warminster Municipal Authority* | Warminster, PA | 10 of 38 | 72.8 ppt | 40,000 |
| Hyannis Water System | Hyannis, MA | 28 of 44 | 50.6 ppt | 35,000 |
| City of Ocala* | Ocala, FL | 2 of 2 | 50.5 ppt | 57,665 |
| City of North Miami* | North Miami, FL | 3 of 3 | 50.3 ppt | 88,349 |
| Artesian Water Company* | Newark, DE | 5 of 61 | 49.9 ppt | 301,000 |
| FKAA J. Robert Dean Water Treatment Plant | Florida City, FL | 2 of 2 | 48.5 ppt | 86,000 |
| Warrington Twp Water&sew Dept | Warrington, PA | 3 of 17 | 48.4 ppt | 21,588 |
| West Morgan-East Lawrence Water Authority* | Decatur, AL | 2 of 4 | 45.0 ppt | 30,000 |
| Montebello Land & Water Company | Montebello, CA | 32 of 34 | 42.6 ppt | 32,219 |
| United Water Pennsylvania | Harrisburg, PA | 1 of 9 | 40.3 ppt | 110,000 |
| V.A.W. Water System, Inc* | Holly Pond, AL | 4 of 8 | 40.0 ppt | 15,582 |
| Gadsden Water Works and Sewer Board* | Gadsden, AL | 3 of 4 | 35.0 ppt | 44,637 |
| Yorba Linda Water District | Yorba Linda, CA | 99 of 103 | 34.7 ppt | 77,513 |
| Widefield WSD* | Colorado Springs, CO | 6 of 17 | 34.6 ppt | 22,414 |
| Liberty Water Lpsco* | Avondale, AZ | 2 of 12 | 34.2 ppt | 50,045 |
| Sanford Water District | Sanford, ME | 2 of 16 | 33.8 ppt | 14,025 |
| Camp Pendleton (South) | Camp Pendleton, CA | 93 of 274 | 33.4 ppt | 39,400 |
| Liberty Utilities - Bellflower - Norwalk | Downey, CA | 14 of 22 | 33.1 ppt | 72,884 |
| Atlantic City Municipal Utilities Authority | Atlantic City, NJ | 5 of 7 | 32.9 ppt | 152,415 |
| City of Martinsburg* | Martinsburg, WV | 16 of 22 | 29.8 ppt | 15,652 |
| City of Miami Beach | Miami Beach, FL | 1 of 2 | 29.0 ppt | 92,307 |
| City of Anaheim | Anaheim, CA | 87 of 118 | 28.3 ppt | 450,000 |
| Hicksville WD | Hicksville, NY | 38 of 90 | 28.1 ppt | 48,000 |
| Downey Water Department | Downey, CA | 13 of 20 | 27.4 ppt | 111,930 |
| City of Pleasanton | Pleasanton, CA | 12 of 22 | 27.3 ppt | 73,067 |
| Freeport | Freeport, IL | 2 of 7 | 26.7 ppt | 25,648 |
| City of Livermore | Livermore, CA | 40 of 50 | 26.5 ppt | 27,000 |
| Dublin San Ramon Services District | Dublin, CA | 40 of 50 | 26.5 ppt | 75,924 |
| City of Garden Grove | Garden Grove, CA | 36 of 57 | 25.2 ppt | 170,883 |
| City of Lauderhill | Lauderhill, FL | 1 of 2 | 24.5 ppt | 55,000 |
| California American Water Company - Suburban | Sacramento, CA | 87 of 245 | 24.0 ppt | 111,768 |
| City of Greensboro* | Greensboro, NC | 5 of 10 | 23.5 ppt | 290,201 |
| Plainfield Township | Mcbain, MI | 3 of 5 | 22.7 ppt | 42,271 |
| Pico Rivera Water Department | Pico Rivera, CA | 39 of 54 | 22.5 ppt | 39,000 |
| City of Corona* | Corona, CA | 114 of 279 | 21.2 ppt | 155,896 |
| City of Lathrop | Lathrop, CA | 17 of 24 | 21.0 ppt | 12,427 |
| Bemidji | Bemidji, MN | 4 of 19 | 20.5 ppt | 15,462 |
| City of Tempe | Tempe, AZ | 6 of 24 | 19.7 ppt | 165,000 |
| Pico WD | Pico Rivera, CA | 11 of 16 | 19.6 ppt | 24,100 |
| Dyer Water Department | Dyer, IN | 1 of 4 | 19.6 ppt | 16,800 |
| Emerald Coast Utilities Authority* | Pensacola, FL | 5 of 52 | 19.2 ppt | 255,884 |
| City of Fountain | Fountain, CO | 4 of 12 | 18.3 ppt | 29,000 |
* 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 Perfluorooctane sulfonate (PFOS), but it likely has the contaminant in its water supply.