Perfluoroalkyl Substances

Background

The chemical structure of PFAS gives them unique properties, such as thermal stability and the ability to repel water and oil, making them useful in a wide variety of industrial and consumer products (fabric stain protectors, waterproofing of fabric, non-stick cookware, food packaging, lubricants, firefighting foams, particularly AFFF (Aqueous film-forming foams).

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are two of the best known and most studied PFAS’. During the manufacturing process of some PFAS, and the use of PFAS products PFOA and PFOS have been released to the air, water and soil throughout the world. PFOA and PFOS have been detected in many isolated parts of the word indicating that long-range transport of these chemicals are possible.

Other PFAS’ of environmental concern include Perfluorooctane sulfonamides, sulfonamido ethanols, Fluorotelomer sulfonates, and other forms of Perfluoro carboxylates and Perfluoro sulfonates.

EPA has found that there is suggestive evidence that PFOS and PFOA may cause cancer (EPA 2016d, 2016e). The World Health Organization’s International Agency for Research on Cancer has found that PFOA is possibly carcinogenic to humans (Group 2B) (IARC 2016). In May 2016, EPA established drinking water health advisories of 70 parts per trillion (0.07 micrograms per liter (µg/L)) for the combined concentrations of PFOS and PFOA. Above these levels, EPA recommends that drinking water systems take steps to assess contamination, inform consumers and limit exposure. The health advisory levels are based on the RfDs (EPA 2016b, 2016c).

ALS Testing Capabilities

The ALS Kelso, WA facility has offered PFAS analysis of water, soil, sediments, biosolids, and tissues matrices for over fifteen years. The laboratory holds DoD accreditation, as well as several state certifications for this analysis.

The ALS laboratory in Kelso, Washington utilizes two methods for the analysis of PFAS:

• In-house analytical method EPA 537-Modified utilizing isotope dilution for water, soil, sediment, and tissues by LC/MS/MS
• EPA Method 537 Rev 1.1 Determination of Selected Perfluorinated Alkyl Acids in Drinking Water by Solid Phase Extraction and Liquid Chromatography/Tandem Mass Spectroscopy (LC/MS/MS)

The Kelso facility offers PFAS analysis of water, soil, sediments, biosolids, and tissues matrices. The laboratory holds DoD accreditation, as well as several state certifications for this analysis.

The standard Method Reporting Limits at the Kelso laboratory are:

• Water: 5 ng/L
• Soil/Sediment: 1 ug/Kg
• Tissues: 0.25 ug/Kg

Sampling Requirements

Care must be taken to ensure samplers are not wearing clothing containing PFAS. Bottles must HDPE, with no Teflon lid. PTFE (Teflon) plus rubber should be avoided during sampling and storage (e.g. tubing, bailers). For further information please contact your local ALS Client Services Team.