March 1, 2011

Science Advisory Board Meeting Minutes
March 1, 2011
Mass DEP: 2nd Floor
1 PM
Members Present: Dave Williams, Larry Boise, Martha Mittelstaedt, Hilary Hackbart, Robin Dodson, Anne Marie Desmarais

Others Present: Heather Tenney (TURI), Carol Rowan West (DEP), John Raschko (OTA), Liz Harriman (TURI), Suzi Peck (DEP), Tracy Guerrero (SEHSC), Wendy Koch (SEHSC), Kathy Plotcke (SEHSC) Tricia McCarthy (ACC), Sean Moynihan (MCTA)

Welcome and Introductions

Program Updates
● The Chromium Policy Analysis was presented to the Advisory Committee and Administrative Council. A draft was circulated. TURI is following up on certain uses/users prior to the final version being completed.
● The draft program calendar was circulated so that members could see what work is upcoming for the SAB and how that fits into the overall program plan for the year. HFE’s, Napthas and the halogenated compounds are up next for the SAB.
● The Decision Making Document has had some small changes. The final version was circulated.
● The 20th Anniversary brochure was distributed.
● A save the date card was circulated for the community conference on April 14th.
● The formaldehyde work at NAS should be done by the end of March. Then the SAB should have a couple of weeks to review it before the next meeting.
● The program is working on Priority User Segments for TCE and Cadmium.

January Meeting Minutes
Approved with edits of three typos.

Materials Submission Policy
The Materials Submission Policy was amended to specify materials be submitted 10 days prior to the SAB meeting.

Higher Hazard Substance Alternatives: VMSs as alternatives to TCE and Perc

Volatile Methyl Siloxanes:
linear VMS’s, evaluating hexamethyldisiloxane - HMDS CAS # 107-46-0
Cyclic VMS’s, evaluating decamethylcyclopentasiloxane - D5 CAS # 541-02-6

The group continued their discussion on HMDS and D5. They reviewed the information provided by the Silicones Environmental Health and Safety Council (SEHSC) and were able to ask questions of their representatives.

The group started off by questioning whether it made sense to have categories of VMSs ( ie cyclical and linear categories). It was decided that it made sense to wait until a decision has been made for one substance and then consider the idea of a category.

The representatives from SEHSC gave an overview of the chemicals based upon what they have studied. The SEHSC representative made the following points (throughout this section comments attributed to SEHSC representatives are in italics):

● It is important to look at chemicals separately

Specific to D5:
● CA OEHHA says it is not a risk
● Health Canada says it is not a human health concern
● EPA Expert Review says there is no risk associated with D5
● a robust data set was submitted to CA last week

Specific to HMDS:
● It is a HPV
● Linear VMSs behave similarly to cyclic in the environment
● It meets screening criteria but there is further work to be done
● EPA Chemical Action Plan has been put on hold
Instead, enforceable consent agreement negotiated with environmental monitoring required (draft end of April)
● Uses:
Cyclic- fabric softeners, personal care, drycleaning
Linear - solvents

The Board then listed their concerns from the previous meeting:
D5
● Carcinogenicity (uterine carcinomas)
● Dopamine agonist
● Estrogenicity
● PBT
● Aquatic toxicity

The Board would like to read the Canadian review. There was discussion on the pathway. There is no demonstrable evidence that D5 is a dopamine agonist. However, it is likely a plausible explanation. There are no other dopamergic responses. It is probably not a carcinogen in humans. Binding to estrogen receptors is weak if at all. Study shows adenocarcinoma in controls possibly through alteration of prolactin. SEHSC: The study showed a very low incidence of tumor that is spontaneously seen. No estrogenic activity – all negative. The Dow study has not been repeated with different species. CA OEHHA noted decreased anogenital distance in males – SEHSC: the study director said this was not a real effect. Several Board members and TURI staff looked for additional studies – none were found. Estrogenicity – followed EPA NSTEP TIER I, could look at Tier II. SEHSC: Dow conducted a sensitive tissue review – no response, no precursor tissue was found.

D5 is highly lipophilic and has a high log Kow. The breakdown products are silanols – silica and co2. There is some concern about aquatic toxicity. Also, accumulation is shown in seals and whales. SEHSC: believes these were contaminated samples- they have seen background air concentrations from personal care products (PCPs), and seen the presence of PCPs contaminate specimens during collection.

Remaining Issues: bioaccumulation may be slow, but still significant. Does it bind or volatilize? Is there toxicity at soluble levels? CA is concerned it might not biodegrade as fast as stated in the article.

Degradation breaks Si chain, sometimes demethylation occurs. D4 is smaller molecule – more is taken up. Otherwise very similar. Not found in wastewater effluent in CA?

The SAB would like more information prior to making a decision. The Canadian Board of Review meets 4/26-5/6. After that SEHSC can provide Canada’s new data. The Board would like more information on today’s questions regarding bioaccumulation and persistence. What is the carcinogenicity mechanism? What is happening downstream?

The Board would like to look at the data regarding the anogenital distance. Also, they would like to look at the 2008 Canadian info and the MOA document.

Motion to table D5 cyclics – unanimous.

HMDS
SEHSC: HMDS is used in all kinds of cleaning. Used in non aggressive vapor degreasing - not dry cleaning.
What is the basis of the Dow exposure limit? SEHSC: Original kidney effects. The Board would like to see these.

The flammability is a concern (flash point 1ºC). It is less flammable than that of acetone ((-20 ºC). HMDS is similar to acetone/MEK (both listed) with flammability hazard as the primary concern.

Discussed whether flammability alone sufficient to list it. It could be listed as low hazard material. Industrial hygiene concerns- OSHA process safety. Physical hazards are important and this is a valid hazard.

Hazard is there- action is needed to reduce risk. There is a need for consistency as well.

Motion to list and place on less hazardous list
5 in favor, 1 opposed

Formaldehyde Update
Heather has been following the NAS process so the Board can be prepared to move forward quickly when the process is complete. Thus far the NAS process seems to be on track for completion. Heather will continue to track the process.

Certain Halogenated Hydrocarbons
Liz handed out a spreadsheet with potential chemicals for a ‘certain halogenated hydrocarbons’ category. Criteria for what should be considered were discussed. The compound should have at least one halogen and less than four carbons. Oxygen doesn’t matter. This would include compounds that likely have good solvent properties. Some of the chemicals that fit these criteria are already listed ( ie TCE, PCE, nPB).

Theoretical compounds continue to be a concern to the Board. That is where we will be most unprepared if they occur. The Board would like to be proactive. It was restated that a category would not absorb any halogenated hydrocarbons that are already specific listed. The Board is still happy with their suggestion of compounds with 1-4 carbons. An interesting sort would be: have they been used as solvents? Some are monomers.
DBCP is in this group. Other important information is: vapor pressure, predominant use, Patty’s, Saks, physical state at room temp, TSCA inventory, molecular weight. Lower molecular weights could be CNSs.

Adjourn

Next Meeting Date: Tuesday 4/26/11@1