September 27, 2017
Toxics Use Reduction Institute Science Advisory Board Meeting Minutes
September 27, 2017
Massachusetts Department of Environmental Protection – 2nd Floor, 1 Winter Street, Boston
1:00 PM
Members present: David Williams (Chair), Larry Boise (Vice-Chair), Denise Kmetzo, Christy Foran, Ken Weinberg, Robin Dodson, Amy Cannon, Chris Rioux, Hilary Hackbart
Program staff present: Liz Harriman (TURI), Heather Tenney (TURI), John Raschko (OTA), Mary Butow (TURI), Rich Bizzozero (OTA)
Others present: Patricia McCarthy (Coyne Legislative Services for ACC), Katherine Robertson (MCTA), Margaret Gorman (ACC), Jessica Bowman (ACC/Fluorocouncil), Steve Korzeniowski (Fluorocouncil), Wendy Heiger-Bernays (Boston University)
Pre-Meeting Presentation
Wendy Heiger-Bernays, Clinical Professor in Environmental Health from Boston University, presented “Per- and Poly-fluoroalkyl Substances (PFAS) Potential Relationships Between Endocrine Effects”. Wendy noted she will add the specific chemicals that are referenced on the slide and the Program can add this updated version to the guide page for the next meeting.
Welcome and Introductions
Program Updates
- TUR Planner Continuing Education Conference to be held, Thursday, November 16, 2017.
- There will be a webinar on nanomaterials featuring Molly Jacobs and Dr. Michael Ellenbecker at noon on December 7, 2017. TURI also released a nanomaterials fact sheet.
- TURI will be moving to Boott Mills in Lowell, in Jan/Feb 2018.
- Some publications were circulated:
- Artificial Turf Fact Sheet
- New TURI Publication: Toxics Use Reduction and Resource Conservation: Competitiveness Impacts for Massachusetts Businesses.
- OTA Resiliency Trainings - Ongoing
Approve May Meeting Minutes
The May minutes were approved as written.
Vote: 6 in favor, 3 abstaining.
PFAS Continued Discussion
At the January meeting, the Board voted to list PFOA/PFOS and their salts based on PBT endpoints. At the March meeting, we continued discussion of human health effects of PFOA/PFOS and introduced PFHxS and PFHxA. In May the Board continued review of the PFHxA (C5/C6 substance) and PFHxS (C6 substance) and received the first draft EHS Summaries for PFBA and PFBS (C4 substances). After the initial review of information for C6, we decided to pull together a table to look at effects across carbon chain lengths. The Program performed a literature search for the acronyms for 7 Substances (PFOA, PFOS, PFHxA, PFHxS, PFBA, PFBS, and PFNA) along with the terms, “2015”, “2016”, “2017”, “toxicity”. The results were separated by endpoint and circulated to the Board over the Summer. A table was then created that included relevant results from the literature search and in many cases information that was included in previously shared EHS summaries for the respective substances. It was noted that the currently assembled table was designed to be used as a tool, and not a final product.
A representative from ACC expressed concern about the non-comprehensive nature of the table and that it did not adequately distinguish between the “short” and “long” chain substances, specifically, distinguishing C6 carboxylic acids from C6 sulfonic acids. Future tables will put them in separate columns, to be clear that the substances have different characteristics. EHS summaries will be updated with the recent information, and other studies that are available.
Depending on the results of the review, the Board could recommend listing specific perfluorinated substances or a category or categories of perfluorinated substances.
Discussion proceeded to review the table by endpoint, and to look for trends and differences across the different chain lengths and carboxylic/sulfonic structures.
PBT: For persistence it was agreed that there was commonality across the table; extreme persistence is demonstrated. There is mixed evidence for bioaccumulation. Evidence on fish toxicity and bioaccumulation has generally shown it to be less of a concern than for mammals, i.e., aquatic toxicity is unlikely to be the driver for concern.
Industry noted information is available from Washington State Department of Ecology (Ecology) regarding concentrations in fish tissue and osprey eggs. Ecology has a Chemical Action Plan for PFAS. There was a request to add Perez 2013 data to table; and also a reminder that industry comments on the Perez 2013 study are on the LibGuide.
There was a suggestion that it would be useful to note the age of the organism in the bioaccumulation studies, where that information is available. There was a note that one study tested for and found a precursor of PFBS in fish.
A visitor asked for more information on references, specifically on bioaccumulation of PFBA and PFBS. It was noted that the references for all information in this table are in the EHS summaries. A visitor also suggested looking at a new 3M blood bank study by Olsen et al, 2017.
Endocrine: ACC noted that they will provide a review of available studies on PFHxA from SETAC in early November.
Gorrochategui was an “immortalized cell line”; Lee et al 2017 showed increasing potency with chain length, C9 was an exception. Li et al 2017 showed apoptosis. It was noted that Halsne et al may show more with regard to teratogenicity.
In each, with the possible exception of C9, we do see disruption in regulation of steroidogenesis and generally lipids but it may not necessarily be due to nuclear receptor binding. It may be enzymatic and happening more at the molecular level.
The Program noted in Zhang 2015a, results indicated that “PFOS may disrupt the secretion of hCG, progesterone and estradiol by human placental syncytiotrophoblasts via induction of apoptosis”. This is significant as the secretion of these hormones is important for the maintenance of pregnancy.
Thyroid:
Comments from the previous meeting were that thyroid effects were seen across chain lengths, but they were not consistently increased or decreased. The pre-meeting presentation was helpful to understand why effects are not consistent up or down. A member noted that they see effects across chain length, but see disparate effects. It was noted that Kim et al numbers overlap w/ high variability.
Immunotoxicity:
Broad spectrum of effects of suppression of immune response; asthma susceptibility. Dong 2013 shows an association between serum PFCs and asthma for PFOA, PFOS, PFHxS, PFBS, and PFNA but not PFHxA.
The Program noted a lack of clarity in the abstract for Rushing 2017 that implied rodent models were being applied to humans. Later in the paper, the author distinguishes the immune suppression effects of PFOA on rodents and humans.
Neurotoxicity:
Significant effects were noted for PFOS, some effects for PFHxS and few studies, but lesser effects (reversible) for PFBS. The half-life is longer for PFHxS than PFOS. The same effects are seen, in particular developmental/neonatal neurotoxicity (e.g., Lee and Viberg 2013).
Zhang 2016 showed longer chains had greater association with synaptic plasticity. Effects are still seen in PFBS, but there is lower neurotoxicity potential.
Reproductive/Developmental effects:
Reproductive and developmental effects seem to be secondary to hormone effects. Sometimes increases were seen in birth weights and sometimes decreases. For decreased birth weights, increased weights were seen later (20 mos.). Women with higher levels of PFAS had earlier menopause (Taylor 2014). Wang 2017 showed endometriosis-related infertility due to PFBS. Increased testosterone was seen in daughters for PFOA, PFOS, and PFHxS (Maisonet 2015). Other effects were seen in lower chain lengths; the same effects were not always seen across chain lengths.
The Board questioned how these effects are connected and whether revisiting the cholesterol pathway would explain part of this. Liver effects may be affected by cholesterol issues. Is it affecting the estrogen pathway? Many different effects were seen and they are not all consistent across carbon chain lengths. At this point it will be helpful to look at different individual substances for effects. A visitor noted that the chemicals interrupting the hormone control process causes the inconsistency of whether the response is increased or decreased.
Next steps:
The hepatotoxicity endpoint will be discussed at the next meeting. Information from the table will be added into the EHS Summaries.
A short discussion followed about how to handle the remaining perfluorinated compounds. We are currently looking at 7; there are potentially thousands more. The Board suggested asking industry directly with regard to precursors and breakdown products (e.g. PFOS and PFOA – salts are direct precursors, there can be indirect precursors as well). A Board sub-committee will also look at the literature for information on direct and indirect precursors.
Next Meeting
Wednesday, December 6, 2017, Location: TBA
Handouts
- Updated Draft EHS Summary for PFHxA
- Matrix of 7 PFCs by selected endpoints
- Professor Wendy Heiger-Bernays presentation “Per- and Poly-fluoroalkyl Substances (PFAS) Potential Relationships Between Endocrine Effects”