On January 24th 2020 WSSC Water announced that they will resume testing its drinking water for the presence of Per- and Polyfluoroalkyl (PFAS) substances at its Potomac and Patuxent Water Filtration Plants. These plants provide drinking water to 1.8 million residents in Montgomery and Prince George’s counties.
This announcement follows the release of a study by the Environmental Working Group that reported WSSC Water’s PFAS levels to be 17.8 parts per trillion (ppt). The study only tested one location within WSSC Water’s service area. Though the level found is well below the U.S. Environmental Protection Agency’s (EPA) health advisory level of 70 ppt, that level is screening level for groundwater contamination, not a health based maximum contaminant level (MCL) for drinking water.
If you recall in February 2019 the EPA announced their Per- and Polyfluoroalkyl Substances (PFAS) Action Plan, taking the first steps in the process to create a maximum contaminant level (MCL) for PFOS and PFOA to regulate these chemicals under the Safe Drinking Water Act. The current guidance provides interim recommendations for screening levels, and preliminary remediation goals (PRGs) to inform final cleanup levels for PFOA and/or PFOS contamination of groundwater that is a current or potential source of drinking water.
There are currently no federal PFAS drinking water standards despite widespread drinking water contamination, ubiquitous population-level exposure, and toxicological and epidemiological evidence of adverse health effects. Communities across the U.S. are discovering drinking water contaminated by PFAS and determining appropriate actions. While there are currently no federal or Maryland state regulations mandating the monitoring or treatment of PFAS, WSSC Water’s PFAS testing program will resume in the next few weeks and results will be posted on its website: www.wsscwater.com/pfas.
WSSC Water conducted extensive water quality testing for six PFAS compounds, from July 2013 through March 2014 and again from April 2015 through October 2017, and reported that all the results of the PFAS were below the EPA detection limits. WSSC Water plans to reach out to the Environmental Working Group study authors to determine their PFAS sampling and testing protocols to better understand why their results differ from WSSC findings. Scientific knowledge of PFAS, including analytical methods, are constantly evolving and now can yield lower detection limits than in the past. The difference in findings may simply be a lower detection limit.
PFOA and PFOS are synthetic fluorinated organic chemicals belonging to a large group commonly referred to as per- and poly-fluoroalkyl substances or PFAS. Manufacturers have produced PFAS for a variety of industries and products, including surface treatments for soil/stain/water resistance; surface treatments of textiles; paper; metals; and for specialized applications, such as fire suppression for hydrocarbon fires, and have been widely used on military bases. PFOA and PFOS are resistant to metabolic and environmental degradation; and therefore, are highly persistent in the environment and can bioaccumulate in humans.
Studies indicate that high concentrations of PFOA and PFOS can cause reproductive and developmental, liver and kidney, and immunological effects in laboratory animals. Both chemicals have caused tumors in animal studies. The most consistent findings from human studies are increased cholesterol levels among exposed populations, with more limited findings related to cancer, thyroid hormone effects, other reproductive and developmental impacts in humans, infant birth weights and adverse effects on the immune system.
Drinking water can be a source of exposure in communities where these chemicals have contaminated water supplies. Such contamination is typically associated with a specific facility, for example: an industrial facility where PFAS were produced or used to manufacture other products, or locations where firefighting foam was used such as oil refineries, airfields or other training facilities for firefighters. Manufacture of these substances did take place in West Virginia, and these substances were widely used.
PFAS include a large number of important chemicals that can be used in some food packaging and can make things grease- and stain-resistant. They were used in firefighting foams and in a wide range of manufacturing practices. Unfortunately, some of these substances don’t break down over time. That means they build up in the environment and in our bodies. The result is that according to the CDC more than 95% of the U.S. population has measurable levels of PFOA and PFOS in their blood; and babies are born with PFOA in their blood.
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