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Perfluorooctane sulfonate (PFOS)

Clearwater Water System

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.

 

10

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2010N/A00N/A
2011N/A00N/A
2012N/A00N/A
2013ND40ND
2014ND50ND
2015ND10ND

ppt = parts per trillion.

State and national drinking water standards and health guidelines

Health Guideline 1 ppt

The 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 PFCs most widely detected in drinking water. This health guideline applies to the entire class of PFCs detected in water.

ppt = parts per trillion.

All test results

Date Result
2013-12-11ND
2013-12-16ND
2013-12-16ND
2013-12-17ND
2014-03-18ND
2014-06-24ND
2014-06-24ND
2014-06-24ND
2014-09-24ND
2015-08-05ND