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PFOS

PFASNo safe level (MCLG 0)
MCL4.0 ng/L
MCLG0.0 ng/L

Legal limit and health goal

MCL — Maximum Contaminant Level

The enforceable legal limit. Public water systems must keep levels at or below this number. Violation triggers a public notice requirement.

4.0 ng/L
MCLG — Maximum Contaminant Level Goal

The non-enforceable health goal set by the EPA. For known or probable carcinogens the MCLG is zero — no level of exposure is considered without risk.

0.0 ng/L

Representative sample reading

Illustrative value at approximately 50% of MCL

Health effects

Liver and thyroid harm, immune suppression, increased cancer risk. A persistent "forever chemical."

Filters verified to reduce PFOS

6 certified

ZeroWater

5-Stage Ready-Pour Pitcher

Pitcher$39.99
NSF/42NSF/53
Verified PartnerView product

Frizzlife

M800 Under-Sink Reverse Osmosis

Under-sink RO$399
NSF/58
Verified PartnerView product

AquaTru

Classic Countertop RO

Countertop RO$449
NSF/42NSF/53NSF/58NSF/401
Verified PartnerView product

Clearly Filtered

Affinity Filtered Water Pitcher

Pitcher$90
NSF/53NSF/58NSF/401
Verified PartnerView product

Waterdrop

G3P800 Under-Sink RO

Under-sink RO$549
NSF/53NSF/58NSF/401
Verified PartnerView product

LifeStraw

Home Water Filter Pitcher

Pitcher$59.99
NSF/53NSF/401
Verified PartnerView product

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Utilities currently reporting exceedances

No utilities in our current coverage are reporting an exceedance for this contaminant.