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PFAS - An Emerging Concern

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PFAS - An Emerging Concern

Monday, Sep 10, 2018

What are PFAS Compounds?

Per- and polyfluoroalkyl substances (PFASs), including PFOS and PFOA, are synthetic compounds that have very strong chemical bonds and do not degrade readily.  They have been used for more than 50 years in products such as paper and packaging, stain resistant fabrics, non-stick cookware, aqueous film forming foam (AFFF), cleaning products, leathers and metal plating.  They were widely used because of their ability to resist adhesion, heat, stains, grease and water.

In terms of chemical composition, PFAS are formed from fluorinated carbon chains that are both hydrophobic and lipophobic in nature.  The carbon-fluorine bond formed in these chemicals is extremely strong and stable, thus reducing breakdown and degradation.

How prevalent is PFAS in the environment?

Because they are stable chemicals and move freely in the environment, PFAS have been found around the world in both the environment and in human blood.   They are classified as emerging contaminants and were included in EPA’s Third Unregulated Contaminant Monitoring Rule (UCMR 3), which monitored contaminants between 2013 and 2015.  The UCMR 3 list contained six perfluorinated compounds that were analyzed in 4,920 Public Water Systems (PWSs).


What regulations have been enacted?

PFAS compounds are not currently regulated at the federal level.   However, the EPA has issued lifetime health advisory limits of 0.07 µg/L for PFOA and PFOS combined in drinking water.   Several states also have current or proposed rules with equal or lower limits.


What are the options available for testing samples for PFASs?

TestAmerica offers PFAS testing at three locations; Sacramento, Denver and Burlington.  Our methods utilize LC/MS/MS technology to achieve reporting limits as low as 0.02 ug/L in water samples and 0.2 µg/kg in soils.  We use EPA Method 537 for drinking water samples, and 537 Modified for other complex matrices (groundwater, soil, tissues, sediment, foam, etc.).

TestAmerica offers a Total Oxidizable Precursor (TOP) Assay preparatory technique in conjunction with the 537 Modified, allowing for a measurement of PFAS risk from precursors.  TOP Assay is a pretreatment oxidation process that mimics the aerobic transformation of PFAS precursors to perfluoroalkyl acids (PFAAs).  The process involves the analysis of both a pre and a post oxidation aliquot of the field sample, providing results for PFAS precursors and PFAS analytes.

To learn more about PFAS and the TOP Assay procedure, please visit our PFAS webpage or contact TestAmerica’s PFAS expert, Karla Buechler.


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