August 27, 2019
The conference room at the Marriott Ypsilanti at Eagle Crest in Ann Arbor, Mich., during the Environmental Research & Education Foundation’s (EREF) Summit on PFAS in Leachate was packed on August 14 and 15, with more than 250 attendees gathered for a day and a half of presentations related to the regulation and management of per- and polyfluoroalkyl substances (PFAS) in landfill leachate.
The topic of PFAS has risen to prominence recently due to detection of the class of compounds in the environment and a push for state regulatory agencies to evaluate (and potentially regulate) where PFAS are being detected. In addition to drinking water, wastewater treatment plants and landfills have fallen under scrutiny. The primary concern regarding PFAS has to do with suspected correlations between exposure to the compounds and their range of adverse health effects (e.g. complications with liver functioning).
The summit provided a variety of perspectives related to PFAS, including basic information regarding what products contain PFAS, a review of health implications based on published science, how prominent the compounds are in landfill leachate, as well as detection and treatment strategies.
A highlight of the meeting was the participation of Michigan’s Department of Energy’s Great Lakes & Environment Director Liesl Clark, who discussed why the state has been at the center of the PFAS discussions. Clark explained Michigan went looking for issues surrounding PFAS rather than waiting for issues to arise and citizens to be left searching for answers. She noted the importance of a science-driven regulatory system, ensuring that policies and practices have a firm foundation and solid reasoning for their implementation.
The event was information packed, and attendees were provided with a number of important takeaways:
PFAS chemicals are everywhere. They are in hundreds of consumer products (e.g. food packaging, clothing, carpet, firefighting foams, etc.), in the air we breathe and have even been detected at the North Pole. According to the Centers for Disease Control, PFAS compounds have been detected in the blood of nearly all of the world’s population.
It’s more than a tall drink of water. Due to the public perception that their water contains harmful chemicals, most agencies are focused on developing regulations or guidelines related to drinking water. However, this approach neglects other routes of exposure, including air and food. Some research suggests drinking water may not be the dominant source of exposure for humans when PFAS concentrations in drinking water are low.
It’s time to expand the focus beyond perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). While PFAS have been used in various products for about 50 years, very little is known about the treatment and management, as well as long-term health and environmental implications of these substances. In fact, there are thousands of PFAS compounds. Most scientific research has focused on the two most widely used compounds, PFOS and PFOA, which have been phased out of use in many places across the globe over the last two decades. In contrast, use of other PFAS compounds have presumably increased. However, there is still a tremendous amount we do not know about these other compounds, other than the number of carbons in the molecules can vary from four (C4) up to 10 (C10).
Science related to health implications is in its infancy. Half-lives in humans and the chemical potency vary based on the carbon length in PFAS compounds. Studies thus far suggest that PFOS and PFOA, which are C8 compounds, behave very differently in the environment and in the human body compared to short-chain PFAS (e.g. C4). As a result, scientific studies on PFOS and PFOA may not be translatable to other PFAS compounds, and one cannot assume that observations for PFOS and PFOA will result in the same results for other PFAS. The dominant PFAS detected in leachate are short-chain compounds. Interestingly, the limited toxicology studies that exist suggest that short-chain (e.g. C4) PFAS have shorter half-lives in the human body and animals than long chain (e.g. C8).
Not all testing methods are created equal. Methods of testing samples for PFAS require standardization in order to accurately determine the presence of these chemicals. A sample sent to multiple labs could return different results depending simply on how it was prepared and what testing was performed. The Liquid Chromatography/Tandem Mass Spectrometry (LC-MS/MS) methodology that includes Total Oxidizable Precursor (TOP) approach provides the most accurate approach. However, TOP characterizes total PFAS, which represents maximum release. Actual release may be less than this.
Additionally, when testing for PFAS, caution should be used. Research or tests that look at total fluorine include non-PFAS compounds; therefore, they are not necessarily an indicator that PFAS compounds are present.
In an effort to fill in the data gaps, in early 2019, EREF released a request for pre-proposals targeting PFAS research and received 115 pre-proposals on the topic. Funded projects will be decided in December.
Additionally, EREF will soon unveil a PFAS webpage that will serve as a resource for basic to detailed information including sources, sinks and health and environmental impacts. As more information and research becomes available, the page will be updated.
EREF is a 501(c)3 charity that funds and directs scientific research and educational initiatives for waste management practices to benefit industry participants and the communities they serve. For more complete information on EREF funded research, its scholarship program and how to donate to this great cause, visit erefdn.org.