PFAST Network researchers with community members at a PFAS public forum in Wilmington (photo by Manal Khan)
NC PFAST Network News June 2019
FROM THE DIRECTOR
Dear NC PFAS Testing Network Colleagues,
This has been a very busy month for the Network. All of our research teams have been conducting field work, laboratory experiments, and presenting at local and national conferences. We are finalizing the latest Quarterly Report due to the Legislature on July 1, 2019. We appreciate each team’s effort in providing us monthly progress reports in a timely manner so we can highlight your activities.
One recent highlight was a PFAS public forum organized by the North Carolina Coastal Federation and hosted by the UNC-Wilmington on May 31, 2019. I want to sincerely thank Tracy Skrabal and her team from the Coastal Federation, and Professor Ralph Mead and his team from UNCW for helping organize this successful event. Thanks also to Professors Knappe (NCSU), MacDonald-Gibson (UNC-CH), Stapleton (Duke), Mead (UNC-W), and DeWitt (ECU) for presenting research aims and preliminary results for Teams 1-5, respectively, and to Drs. Gray (UNC-CH), Hoppin (NCSU), and Weintraub (Duke) for Team 6’s help with public engagement. For those who were unable to attend, you can check out all the presentations here.
Professor Knappe also recently organized a Regional PFAS Information Exchange Meeting with participation from the PFAST Network, EPA, DHHS and DEQ. The meeting included updates and discussion about ongoing PFAS research and government activities in North Carolina, and strategies for each organization to leverage its unique strengths and mandates and work together to address the issue of PFAS in the state in a more comprehensive and collaborative manner. One topic of significant discussion was risk communications and making sure the state’s residents are able to easily access and understand PFAS-related technical and scientific data and related guidance.
The PFAST Network held an Executive Advisory Committee (EAC) meeting this past week focusing on the topic of communicating PFAS testing results from Team 1’s water sampling to the public in a timely and accessible manner. Specifically, we discussed what the PFAST Network’s internal process should be in terms of reporting validated analytical results to each local site whose water was tested. Recent thoughtful discussions with DEQ and DHHS informed some of the updated EAC recommendations and strategic direction that will be used by the Network in coming weeks and months in reporting PFAS testing results to each site. This will build on the experience of communicating the first testing results indicating high PFAS levels that were shared recently with the town of Maysville. In that case, the PFAST Network, DEQ and DHHS were all able to work with the Town to support its responses to the high PFAS detection report. Read more about this process here and under ‘Happenings’ section further down this newsletter.
Finally, the PMT would like to remind remaining teams to please look out for and respond to PMT requests for scheduling site visits in the next few weeks. Although we are using these visits to see how things are going, we also hope you will use this as an opportunity to discuss your needs with us so we can help in any way possible. Please also remember that we have an internal Science Meeting scheduled for Friday, August 9th, 2019 starting at 9 AM in Chapel Hill. Additional details and agenda will be shared closer to the date and we hope each team will be able to present on preliminary data.
Everyone please keep sharing upcoming events with us so we can share this information with the full Network. Thank you all for your hard work and continued collaboration. Have a great July!
Best Wishes, Jason Surratt, PhD
Professor of Environmental Sciences and Engineering
Gillings School of Global Public Health
NOTE: We have added as many PFAST Network researchers (PIs, post-docs, other scientists and students) to this listserv as we could. Feel free to forward this to anyone we missed and let us know if someone should be added.
Quarter 4 Network Report to NC Legislature – due July 1st July Monthly Progress Report - due July 29th
Quarter 4 Financial Report – Aug 5th
PFAST Network Science Meeting – Aug 9th
Meet a Network Scientist
VIVEK PULIKKAL, UNC-C (Team 3) Can you provide background information about yourself? I have a Bachelors in Civil Engineering from Cochin University of Science and Technology and a Masters in Environmental Engineering from IIT Guwahati. Currently, I’m pursuing my Ph.D. in Infrastructure and Environmental Systems at UNC Charlotte. My main area of interest is drinking water treatment.
How did you get involved in the PFAST Network? What are you doing? As part of my Ph.D. dissertation research, I am working on the electrochemical degradation of PFAS compounds. My Ph.D. advisor, Dr. Mei Sun, is part of the PFAST Network and is one of the key persons on the ‘PFAS removal testing team’. She was the one who introduced me to the PFAST Network.
Currently, I’m working on the electrochemical mineralization of two legacy PFASs, PFOA, and PFOS. This project is funded by the Water Resources Research Institute (WRRI) and the USGS. These PFAS compounds are recalcitrant to conventional drinking water treatments and there is no known natural degradation. Hence, through our research, we are aiming to use electric current to break down these compounds to harmless inorganic end products.
Which people in your field have been most influential to you and your career? Dr. Mei Sun, my Ph.D. advisor, has been the most influential person in my career. Her support and guidance have been invaluable to my research. I have been working with her for the past 3 years and it has been a great experience.
What major future research questions do you hope to address (PFAS related or otherwise)? Currently, legacy PFAS compounds are replaced by alternative PFAS compounds like GenX. But we don’t have proper degradation techniques for these compounds. I’m interested in exploring the possibility of using electrochemical degradation as a viable treatment for these replacement compounds. The impact of dissolved organic matter on the efficiency of electrochemical degradation is also of interest to me.
PFAS Article Highlight
Interspecies differences in perfluoroalkyl substances (PFAS) toxicokinetics and application to health-based criteria Daniella M. Pizzurro, Mara Seeley, Laura E. Kerper, Barbara D. Beck Regulatory Toxicology and Pharmacology, 106 (2019) 239-50 https://doi.org/10.1016/j.yrtph.2019.05.008
The authors present a summary of their analysis of published toxicokinetic data on the ADME (absorption, distribution, metabolism, and excretion) properties of five environmentally relevant PFAS (PFOA, PFOS, PFBA, PFBS, and PFHxS) in mammalian species and discuss how such data can help inform human health risk assessment. They selected these PFAS based on variable chain lengths, a broad range of half-life values, and availability of toxicokinetic data in animals or humans. They assessed data from 70 studies identified through comprehensive reviews conducted by the ATSDR and the US EPA as well as through PubMed searches (Jan.2009 – May.2018). Specifically, they evaluated species- and gender-specific target organ distribution and relative PFAS levels, biological half-lives, and patterns of placental and lactational transfer.
In general, the data supports that PFOA, PFOS, and PFBS preferentially distribute to the liver in most mammalian species, and that PFBA and PFHxS appear to preferentially distribute in serum (and to a lesser extent liver) in animals. The only broad human tissue distribution study, in which PFAS levels were measured in tissues of 20 cadavers, suggests that while PFOA preferentially distributes to liver, PFOS, PFHxS, PFBS, and PFBA may preferentially distribute to kidney in humans (Perez et al., 2013). The authors also concluded based on available data that PFOA and PFOS do not readily cross the mature blood brain barrier (BBB), but there are indications from rat studies that that PFAS can cross the undeveloped fetal and newborn pup BBB.
Substantial differences were observed in PFAS elimination rates between humans, monkeys and rats, with much longer half-lives found in humans for the 5 PFAS evaluated (PFHxS > PFOS > PFOA > PFBS > PFBA and humans > monkeys > rodents). Urinary excretion of PFOA and PFHxS is greater for female rats and urinary excretion of PFBA is greater in female rats and mice.
While additional studies are needed, observed similarities in placental and lactational transfer of PFAS coupled with differences in ratios of offspring to maternal blood concentrations of PFOA and PFOS highlight the importance of considering toxicokinetic differences between species for risk assessment purposes. Data suggest that the developing human fetus would be exposed to lower serum PFOA, PFOS, and PFHxS than would the rat fetus. However, the newborn breastfed human infant would be exposed to higher serum PFOA concentrations than the newborn rat.
Regulators are faced with the very difficult challenge of deriving health-protective goals for PFAS contaminants. While legacy PFAS like PFOA and PFOS have been more extensively studied, additional data are needed for emerging PFAS with varying chain lengths and functional groups. Scientists and regulators must determine whether (or not) data for one substance can be applied to the evaluation of other PFAS. Toxicokinetic data are important for extrapolating health effects and effect levels observed in laboratory animals to humans. Accounting for interspecies differences (uncertainty factors) in chemical-specific parameters such as half-life and volume of distribution in the development of PBPK (Physiologically Based Pharmacokinetic) models is important for calculating human equivalent doses and enhances the risk assessment process by reducing some of the uncertainty surrounding health-based criteria. Furthermore, toxicokinetics can help determine whether observed associations are caused by a chemical exposure or can be explained by reverse causation (where the health condition causes an increased body burden of chemical, as opposed to the chemical causing the health effect).
WORKING WITH TOWN OF MAYSVILLE
Earlier this summer researchers from the PFAST Network detected high levels of PFAS in the raw water sample taken for testing from the well which was used as the Town’s source of water. Of the 55 PFAS compounds tested for, the Network found the combination of PFOA and PFOS compounds at a level of 103 parts per trillion (ppt) and PFHxS compound was detected at a level of approximately 100 ppt. After independent testing confirmed these results and discussions with state environmental and health agencies, Maysville switched to the Jones County water supply (which was confirmed to have no high PFAS levels detected). Town of Maysville shared testing activities and other updates with the public here. Additionally, Network scientists Detlef Knappe and Lee Ferguson (Team 1) whose labs had originally tested the Maysville water were able to virtually attend a special town hall session focusing on this issue and talk with local officials and concerned citizens. Specific concerns included the potential sources of the PFAS contamination (which may be a type of aqueous film forming firefighting foam) and practical remediation methods. Check out a local media report of the meeting here.
UPCOMING LOCAL CONFERENCE (Aug 12th-15th):SETAC/Environmental Risk Assessment of PFAS
This SETAC North America Focused Topic Meeting will synthesize recent advances in chemistry, environmental fate and exposure, human and ecological toxicity, and risk characterization of PFAS. The objective of the meeting is to review new and emerging information on PFASs and to formulate a roadmap for a risk assessment approach for PFAS. More information can be found here.
UPCOMING WORKSHOP (Sep 24th-26th): 16th Annual EPA Drinking Water Workshop
This free annual workshop will be held in Ohio in partnership with the Association of State Drinking Water Administrators to provide in-depth information and training on various solutions and strategies for handling small drinking water system challenges. The technical sessions will include topics such as: contaminants of emerging concern, risk management and crisis communication, and disinfection residuals and byproducts. More information can be found here.
UPCOMING WORKSHOP (Sep 26th-27th): Identifying Opportunities to Understand, Control, and Prevent Exposure to PFAS
This upcoming workshop of the National Academy of Sciences’ Environmental Health Matters Initiative will explore human exposure to PFAS, discuss options for controlling PFAS exposures, and consider innovative approaches for preventing PFAS exposures. The ultimate goal is to explore opportunities for partners across public, private and other sectors to advance the understanding about the extent of human exposure to PFAS and to reduce or prevent PFAS exposure. More upcoming information will be found here.
NC Policy Watch: DEQ finds 20 types of PFAS in compost headed for gardens, farms and playgrounds (May 29)
NC Department of Environmental Quality (DEQ) sampled compost produced at the McGill facility in Sampson County and detected 20 types of PFAS compounds from the 33 PFAS sampled for, with concentrations as high as 54.8 parts per trillion (ppt). McGill receives a variety of materials that are turned into compost including peanut shells, swine waste and sludge from municipal wastewater treatment plants making it difficult to pinpoint the contamination source. NC’s compost rules up for review this year don’t require compost facilities to test for PFAS, but these rules are currently open for public comments. Find the public comments link and read more here.
PBS Newshour: FDA food testing finds contamination by PFAS and other ‘forever chemicals’ (Jun 3)
The Food and Drug Administration (FDA)’s first broad testing of food for PFAS compounds found substantial levels in some grocery store meats and seafood and off-the-shelf chocolate cake. PFAS levels in nearly half of the meat and fish tested were double or more the one currently existing federal advisory level, and the level in the chocolate cake was more than 250 times this nonbinding health advisory level of 70 parts per trillion (ppt) for the sum of PFOA and PFOS compounds. PFOS turned up at levels ranging from 134-865 ppt in a variety of meat products and prepared chocolate cake tested at 17,640 ppt for a PFAS called PFPeA. Read more here. RELATED: Read the full FDA statement and findings here.
Intercept: Teflon Toxin Safety Level Should Be 700 Times Lower Than Current EPA Guideline (Jun 18)
According to the nation’s top toxicologist, new data suggests the safety threshold in drinking water for a PFAS called PFOA may be as low as 0.1 parts per trillion (ppt). Linda Birnbaum, director of the National Institute for Environmental Health Sciences, cited this number at a recent PFAS conference based on results from research on rats done by the agency which showed rats developing pancreatic tumors at very low exposures to PFOA. Federal agencies are prioritizing other PFAS research to further understand health effects on humans. Read more here.
Star News: PFAS levels spike in the Cape Fear; could be tied to drought (Jun 21)
Water drawn from the Cape Fear River in early June shows the highest levels of PFAS levels since last September, according to the latest test results from Cape Fear Public Utility Authority (CFPUA). Analysis of raw water sampled by CFPUA showed total PFAS levels at 262 parts per trillion (ppt) and the levels in finished, treated water from the Sweeney plan at 119 ppt. CFPUA states the majority of the PFAS compounds detected are ones identified as originating from Chemours’ Fayetteville Works facility, and low river flows in the region may be raising PFAS concentrations in the water. Read more here.
Publications and Other Research
Food and Chemical Toxicology (May 2019): Do conventional cooking methods alter concentrations of per- and polyfluoroalkyl substances (PFASs) in seafood?
Matthew Taylor, Sandra Nilsson, Jennifer Bräunig, Karl Bowles, Victoria Cole, Natalie Moltschaniwskyj, and Jochen Mueller https://doi.org/10.1016/j.fct.2019.03.032
Environmental Science: Processes and Impacts (May 2019): The concept of essential use for determining when uses of PFASs can be phased out
Ian Cousins, Gretta Goldenman, Dorte Herzke, Rainer Lohmann, Mark Miller, Carla Ng, Sharyle Patton, Martin Scheringer, Xenia Trier, Lena Vierke, Zhanyun Wang, and Jamie DeWitt https://doi.org/10.1039/C9EM00163H Chemosphere (Jul 2019): Temporal trends and sediment–water partitioning of per- and polyfluoroalkyl substances (PFAS) in lake sediment
Dauren Mussabek, Lutz Ahrens, and Kenneth M. https://doi.org/10.1016/j.chemosphere.2019.04.074
Environmental Working Group Data Analysis Finds 475+ Potential Industrial Sources of PFAS Across America Government data analysis and interactive map compiled by the non-profit identifies industrial facilities across America that are known to and suspected of discharging PFAS chemicals into the environment. Data has been collected from EPA’s Chemical Data Reporting Rule, EPA’s Enforcement and Compliance History Online and a survey by New York Department of Environmental Conservation. There are currently no restrictions on industrial PFAS discharges under either the federal Clean Water Act or the federal Clean Air Act. https://www.ewg.org/news-and-analysis/2019/06/pfas-nation-toxic-discharges-suspected-almost-500-industrial-facilities