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Toxic Torts and Environmental Law

PFAS in the water and soil: Why should you care?

By Debra A. Kaden, PhD, ATS

By Debra A. Kaden, PhD, ATS

Toxic Torts & Environmental Law - Spring 2020 Newsletter

The past year has seen an increased sensationalizing on the chemical perfluorooctanoic acid (PFOA) in the media following the airing of the “Erin Brockovich-” style movie “Dark Waters” (November 2019). PFOS are part of a larger family of man-made chemicals, per- and polyfluoroalkyl substances (PFAS), that are used to manufacture many everyday household products including Teflon/nonstick cookware, food packaging like pizza boxes, Scotchguard for shoes and fabrics, and firefighting foam.

The movie Dark Waters tells the story of a former corporate defense attorney, Rob Bilott(Mark Ruffalo), who takes on DuPont for their use of PFOA in Teflon. Bilott initially investigates a claim filed by a West Virginia farmer of dying cows in Parkersburg, a town with farms that Bilott had visited as a child visiting his grandmother. The claim eventually leads to DuPont’s reaching a $16.5 million settlement with the Environmental Protection Agency for violation of the Toxic Substances Control Act, and a subsequent class action suit of more than 3,500 plaintiffs in West Virginia that won a $671 million settlement from DuPont. The class action suit also resulted in a large study in West Virginia that reported traces of PFOA in drinking water.

At the Toxic Tort & Environmental Law 28th Annual Spring Conference in San Diego (April 2019), a panel of distinguished speakers addressed the area of PFAS. Moderator Debra A. Kaden, PhD, ATS (Ramboll) led panel members Antonia Calafat, PhD (Centers for Disease Control and Prevention [CDC], Atlanta, GA); Elizabeth (Betsy) Behl (Health and Ecological Criteria Division, US Environmental Protection Agency [EPA], Washington, DC); Sarah T. Hansel (Berezofsky Law Group, Cherry Hill, NJ); and Adam Baas (DLA Piper, San Francisco, CA) in a discussion of the current science, regulatory landscape, findings and litigation activity revolving around the use of PFAS and its family of chemicals. This article is based on presentations from this Meeting.

Over the past few years, attention to PFAS has increased due to the persistent and widespread detection of these chemicals in the environment and in people. This is duetoboththeincreasingsophisticationoftechnology todetecteventraceamounts of chemicals and the increasing public concerns. PFAS were first introduced in the 1930s for military use but was not in commercial products until the 1950’s when it was used for non-stick cookware. In the mid-1960s, the US Navy developed a highly efficient type of firefighting foam, “aqueous film forming foam” (AFFF), which was soon adopted at civilian locations such as municipal airports, refineries, fuel tank farms, and other industries. Since the early 2000s, many of the chemicals, including PFOS, perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and select PFAS have been phased out of production, with replacements being introduced. For example, PFOS in AFFF has been replaced with 6-carbon PFASs (presumably easier to degrade in the environment than the 8-carbon PFOS and PFOA) starting in 2002. Although PFOA and PFOS are no longer manufactured in the United States, they are still produced in other parts of the world and can be imported in consumer products.

Studies done by industry and government researchers show that PFAScanbefound in blood, and at much lower levels in urine, breast milk and in umbilical cord blood. PFAS stay in the human body for long periods of time, don’t break down and can accumulate. As a result, as people get exposed to PFAS from different sources over time, the level of PFAS in their bodies may remain far beyond the exposure period. The majority of the United States population has had some exposure to PFAS and would likely show some level of PFAS in their blood, especially PFOS and PFOA, if tested. However, this is not completely surprising as there are many chemicals, metals, and toxics at various levels that can be found in the blood and tissue of the US population (e.g., PCBs, etc.). Over the past 10-15 years, the concentrations of the PFAS family of chemicals in blood of the general population has decreased but PFOS or PFOA are still detected at trace concentrations in the blood of ~95% of the general population. Higher concentrations have been observed in occupationally exposed populations and where PFOA has been found in drinking water.

PFAS are a complex group of chemicals, and their persistence in the environment and in the body varies across specific chemicals, across species (including between animal models and people), and even across gender (in animal models). Some discordant results between PFAS epidemiology studies in people and toxicology studies in animals can be explained by species-related differences in cellular responses. Other inconsistencies between epidemiology and toxicology studies have also observed; and for some effects, animal evidence is lacking, and epidemiological evidence is limited. Regulatory determinations depend on the data in hand, even if there is conflicting evidence. Derivation of regulatory values is therefore not the same as conclusive evidence that exposure to a chemical or agent causes disease in people. To date, the majority of studies have addressed PFOA and PFOS uniquely, however, the class of chemicals includes thousands of different chemical species.

The CDC has an ongoing program known as the National Health and Nutrition Examination Study (NHANES). In addition to nutrition and health, this program studies some chemical exposures, including PFAS. Through questionnaires, environmental monitoring, personal monitoring (hand wipes, personal sampling, and other methods), and biomonitoring (assessment of internal dose of a chemical or its metabolites in human samples including blood or urine), information on exposures in a probability sample of the US population can be inferred. NHANES incorporated PFAS monitoring in a subset of participants starting in 1999. The findings are reported every 2 years, with results used to set reference ranges, track temporal trends, monitor interventions, assist with prioritization, and inform exposure or risk assessment. For PFAS, while most US adults and children show blood evidence, the phase-out of production of the chemical family is reflected in a steady decline of the biomarker in human blood in both adults and children. For example, from 1999 to 2014, blood PFOS concentrations have declined by more than 80%; during the same period, blood PFOA levels have declined by more than 60%. Similarly, concentrations of PFAS in the blood decline after intervention is implemented – for example, blood PFAS concentrations decreased in people exposed to PFAS in drinking water after a water filtration system was installed. However, the continuing presence of PFAS found in the blood of children born after manufacturing changes demonstrates the persistence of these chemicals in the environment. 

To regulate PFOA and PFOS based on current knowledge, EPA extensively reviews available scientific literature addressing multiple toxicological endpoints and modeled average blood serum values using a pharmacokinetic model (rat, mouse, and monkey) to derive candidate reference doses (RfDs) for these two chemicals. Data was modeled from multiple studies for potential effects on various health outcomes, including reproduction and developmental effects; effects on blood serum lipids and total cholesterol; liver and kidney effects; and the immune system effects. Under the EPA’s Cancer Guidelines, there is suggestive evidence for cancer potential for PFOA and PFOS. For both chemicals, multiple studies of both short-term and longerterm exposures and based on various adverse effects fall within a narrow range. EPA selected the RfD based on developmental effects in rodent studies to calculate a health advisory protective for the general population and sensitive lifestages. Toxicity values are being developed for GenX chemicals and PFBS, and then will be developed for other PFAS including PFNA and other PFAS (perfluorobutyrate [PFBA]; perfluorohexane sulfonic acid [PFHxS]; perfluorohexanoic acid [PFHxA]; perfluorodecanoic acid [PFDA]).

As part of their Action Plan for PFAS, in December 2019 EPA issued Interim Recommendations for Addressing Groundwater Contaminated with PFOA and PFOS, which provides cleanup guidance for federal cleanup programs (e.g., CERCLA and RCRA) that will be helpful to states and tribes. The guidance recommends using a screening level of 40 parts per trillion (ppt) separately or combined to determine if PFOA or PFOS is present at a site and may warrant further attention. The preliminary remediation goal is EPA’s PFOA and PFOS Lifetime Drinking Water Health Advisory level of 70 ppt, unless state, tribal, or other applicable or relevant and encompassing requirements are available or sufficiently protective. This guidance is meant to provide a clear and consistent roadmap for federal cleanup programs and protect drinking water resources in communities across the country. The EPA has committed to following through on the regulatory development process for listing certain PFAS as hazardous substances under CERCLA. To this end, an advanced notice of proposed rulemaking was published in the Federal Register soliciting input on adding PFAS to the Toxics Release Inventory toxic chemical list. A supplemental proposal was sent to the Office of Management and Budget (OMB) to ensure that certain persistent long-chain PFAS chemicals cannot be manufactured in or imported into the United States without notification and review under the TSCA.

On February 20, 2020, EPA issued preliminary determinations to regulate PFOA and PFOS in drinking water. This plan, if eventually finalized, would set maximum contaminant levels, or limits, in drinking water for the first time for PFAS chemicals that would apply to all water utilities across the country. 

On April 3-4, 2020, the 29th Annual Toxic Tort & Environmental Law Spring Conference will be held at the historic Hotel Del Coronado in Coronado, CA. A follow-up panel “PFAS: An ‘Emergent Contaminant’ Twenty Year Later” will present perspectives including federal- and state-specific environmental practices, in-house, and former regulatory panelists to compare and contrast recent developments, and discuss strategies and tactics for solutions to engage stakeholders and mitigate liability

Debra A. Kaden, PhD, ATS

Senior Practitioner - Ramboll’s Health Science

Debra A. Kaden, PhD, ATS is a senior practitioner in Ramboll’s Health Science practice. Dr. Kaden’s experience has been recognized by the Academy of Toxicological Science (ATS), and is active in multiple professional societies.

Debra Kaden brings over 30 years of experience in toxicology and environmental health sciences with particular emphasis in the area of air toxics and community exposure to air pollution. Debra’s expertise includes critical reviews of the toxicological effects on human health of many of the volatile organic compounds potentially associated with emissions from O&G development and mid-stream transport, including benzene, acrolein, and formaldehyde. She is skilled in evaluating the scientific literature relevant to assessing health impacts of industrial activities on communities. Her experience in the field of exposure sciences issues allows an appreciation of spatial and temporal influences on potential community exposures. Specialties: Toxicology, environmental health, and exposure sciences.

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