Sampling PFOAs and PFOS: What you should know

Poly- and Perfluoroalkyl substances (PFOA’s and PFOS’s) have been all over the news lately, but you may be asking yourself “why?”. Well, the United States Environmental Protection Agency(USEPA) Health Advisory Levels established in 2009 for Perfluorooctane Sulfonate (PFOS)and Perfluorooctanoic Acid (PFOA) went from 200 and 400 parts per trillion (ppt) to 70 ppt, both individually and combined, in 2014. This change can be attributed to an improved understanding of the chemicals toxicity, exposure pathways and health effects, and the need to better protect the public. Using the USEPA’s health advisory as requested by the New York State Department of Health (NYSDOH), the New York State Department of Environmental Conservation (NYSDEC) filed a Notice of Emergency Adoption and Proposed Rule Making to classify PFOA and PFOS as hazardous substances.  The emergency rule originally went into effect in April of 2016, and will become final March 3, 2017. With established regulatory levels and laboratory detection limits so low, cross contamination during sample collection has become a problem. Trace background levels both in the field and at the laboratory, like that from rain or some drinking water systems, are detectible in some samples and can cause inaccuracy problems. Therefore, sampling for these compounds is not your typical routine sampling event and analysis program.pfoa_8-2_ftoh-500x133

Staff collecting the samples need to not only be careful of what they wear, but their field equipment too. Lotions, cosmetics, sunscreen and insect repellents should not be worn that day, save synthetic or 100% natural fiber materials and N,N-Diethyl-meta-toluamide (DEET) products. Tyveks and weatherproof treated (Goretex) items should not be worn, but polyvinylchloride (PVC) and powderless nitrile gloves are okay. Ballpoint pens and loose-leaf paper should be used in lieu of sharpies and waterproof field books. Well washed clothes (at least six washings) without the use of fabric softener should be worn. Aluminum foil and post-it notes should not be used during the sampling process but duct tape can be. Lastly, prepackaged food products should be eaten away from the sampling areas and hands should be thoroughly washed after handling such packaging.

While disposable or dedicated stainless steel or high-density polyethylene (HDPE) equipment are ideal, items made with fluoropolymers are not to be used, there are always pieces that need to be decontaminated. Not only should proper decontamination procedures be followed, but it is important your source water and cleaning chemicals are PFAS free. Be sure to send your samples to a qualified laboratory and collect your quality assurance/quality control (QA/QC) samples, like field, equipment and trip blanks, as well as duplicate, matrix spike and matrix spike duplicate samples. Bottleware used during sampling should be HDPE or glass without Teflon lined caps. When sending samples to the lab, use wet/dry ice, not Blue (chemical) Ice.

If you or your business has any questions regarding PFOA and PFOS storage, handling, regulations, health concerns, past usage, or sampling please call Walden Environmental Engineering  at (516)624-7200.

Comments

Leave a Reply

Your email address will not be published.