Experts Corner: An Update on PFAS
Media coverage has generated significant awareness of and questions about the risks of perfluoroalkyl substances, chemicals also known as PFAS.
Here, we provide answers to some of the questions surrounding PFAS, and summarize some common practices implemented to manage the risks associated with their legacy.
What are PFAS and what do they do?
PFAS— stands for perfluoroalkyl and polyfluoroalkyl substances, which is a group of chemicals, comprised of over 3,000 individual compounds. Two common examples are perfluorooctanesulfonate (PFOS) and perfluorooctanoic acid (PFOA).
For decades, a number of these compounds were used in range of industrial and consumer applications and processes like plating, material coating, lubrication, and vapor suppression. Because of their heat, water, and oil resistance, they were also used in cookware and food storage and packaging products, and to provide stain protection and fire retardancy in apparel, carpeting, and upholstery. PFAS were also a major component in aqueous film forming foam (AFFF), used to extinguish gasoline fires and other refined fuel fires.
What do we know about the health risks of PFAS?
After decades of use and disposal of of these chemicals, PFAS made their way into soil and groundwater. The main route of human exposure is via ingestion, upon which PFAS can be absorbed by and can accumulate in the human body.
Research to date suggests that exposure to PFAS may pose a number of potential health risks, including hypertension during pregnancy, low infant birth weights, increased blood cholesterol, and a higher risk of developing conditions as wide-ranging as liver disease, thyroid disease, asthma and possibly infertility.
PFAS are considered to be an “emerging contaminant,” such that the level of research into the health effects for these compounds has not caught up with many other environmental contaminants.
Some PFAS compounds, like PFOS and PFOA have been sufficiently studied for the United States Environmental Protection Agency (EPA) and other state agencies like the Michigan Department of Environmental Quality (MDEQ) to issue health advisories or standards for those compounds, while other PFAS compounds have not been adequately researched to develop health standards.
What Standards has the EPA Established for PFAS?
In 2009, the EPA issued the first in a series of informational announcements called health advisories, which include technical information, analytical methodologies and remediation technologies.
Note that, although helpful, EPA Health Advisories are recommended guidelines, not enforceable regulatory policies.
That first health advisory recommended a drinking water standard for PFOS and/or PFOA of 200 parts per trillion (ppt). A second health advisory, released in May 2016, established a lower recommended threshold for the concentration of PFAS in drinking water – 70 ppt for the sum of both PFOA and PFOS.
For reference, one part per trillion (ppt) is equal to one drop of water in the combined volume of 20 Olympic swimming pools.
What is Michigan doing?
In the absence of enforceable federal standards, several states including Michigan have moved forward with developing their own regulatory standards for PFAS.
In early January 2018 the MDEQ adopted the EPA recommendation of 70 ppt for PFOS and PFOA combined as an enforceable drinking water standard.
In June 2018, the MDEQ followed up with standards for releasing the chemicals into surface water and soil. For surface water and/or water discharging into surface water, as is commonly the case for waste water treatment plant effluent. The standards are 12 ppt for PFOS and 12,000 ppt for PFOA. The soil standards are 240 ppt for PFOS and 10,000 ppt for PFOA in soil.
Reconciling the Michigan drinking water and surface water standards presents a challenge, as the. standards published in June 2018 indicate that water considered safe to drink (PFAS detected but less than 70 ppt) when it comes out of a tap is not considered appropriate to send down the drain.
It is expected that as research evolves, alternate and possibly more restrictive standards may result.
The MDEQ has required that all 1,800 public water suppliers and all public waste water treatment plants complete PFAS testing by the end of the year. The widespread nature of this testing is expected to illustrate whether widespread PFAS impacts may be present in surface and groundwater across the state.
What are manufacturers doing?
Regulators, municipalities, and industry are responding to the potential threats and regulatory requirements associated with PFAS. Manufacturers, especially those generating industrial waste water are moving to reduce or eliminate PFAS from their waste streams
The first logical step, which many manufacturers have already taken, is to stop using PFOS and PFOA. This often requires an evaluation of materials and chemicals used in the production process and is frequently undertaken as part of an environmental compliance audit.
However, since many production chemicals may not be sufficiently characterized to guarantee that they do not contain those compounds, and because in some instances the production process itself can generate them, many manufacturers have opted to update their waste water treatment facilities to ensure that they can maintain both production and compliance in the face of evolving regulatory PFAS standards.
Updating storm water and spill response plans to eliminate or contain potential discharges of PFAS containing storm water runoff or process chemicals, also assists with managing those risks.
What are property owners and operators doing?
For properties with documented PFAS contamination, proper soil and groundwater investigation is critical to determine the extent of contamination and whether the contamination is stable or migrating. Doing so will identify pathways via which contamination may migrate and potential human and non-human receptors.
In many instances, eliminating contaminated groundwater as a drinking water source is the primary action required. This can be done by eliminating water supply wells, connecting a property to the municipal water supply, or installing a water treatment system. However, if significant contamination is present or a PFAS plume is migrating or venting to surface water, other active remediation methods or engineering controls may also be required.
In the case of a prospective purchaser, environmental due diligence activities including a Phase I Environmental Site Assessment (ESA) should identify potential PFAS uses or sources. If documented, Phase II sampling activities should be conducted to determine if they are present in soil and groundwater, and to develop a plan to manage or mitigate identified risks and quantify potential costs as part of the purchase decision.
As a leader in environmental risk assessment and regulatory compliance, PM Environmental is closely monitoring the evolving science and policy, and we are working with governmental regulators, municipal authorities and property owners to stay at the forefront of the complex, rapidly evolving PFAS landscape.