Green Science Policy Institute Symposium: Science and Policy of Highly Fluorinated Chemicals

Transcription

1 Green Science Policy Institute Symposium: Science and Policy of Highly luorinated Chemicals Risk Reduction Approaches for PASs in Canada with a ew Substances Perspective C H C H C H Graham S. White ew Substance Assessment and Control Bureau Health Canada Golden, Colorado. July 12, 2015.

2 Presentation Content utline Describe the role of the ew Substances Program (SP). Explain the Regulatory Tools available to the SP. Describe our Prohibition of 4 fluorotelomer-based polymers. Discuss our experience with C6 PA replacement chemistry. Summarize our current surveillance activities. Provide a summary of GoC PA regulatory activity.

3 Aspects of the ew Substances Program of Health and Environment Canada Purpose of the ew Substances Program (HC & EC): To ensure no new substance is introduced into Canada before an assessment is made as to whether it is or it could become toxic to Human Health or the Environment. A new substance is any substance not currently listed on the Domestic Substances List (DSL). That is a substance not presently in commerce. The scope of the SP includes chemicals, polymers and products of biotechnology.

4 Aspects of the ew Substances Program of Health and Environment Canada (Continued) Uses a tiered approach (by volume) to assess import and manufactured quantities of substances. ~500 ew Substance otifications (Ss) per year. The onus is on Industry to supply information and test data. The onus is on Government to assess the info and take action where warranted in a timely manner. EC assesses risk to the environment (P,B,iT). HC assesses human health risk

5 Aspects of the ew Substances Program of Health and Environment Canada (Continued) Regulatory tools available to the SP as control measures: Significant ew Activity (SAc) otices, Conditions of use and/or release, Prohibitions. In 2004, the SP prohibited the commercialization of four fluorotelomer-based substances (polymers). These were suspected of being toxic as ultimate sources of perfluorinated carboxylic acids (PCAs).

6 H These are they: n * Mn = 3,830, Mw = 9,094 Where n = 3-6 m x y z n H R * n H Mn = 7,930 a + S 6 6 R H x H H H + R' + a b c Cl d e f g Cl H H R'' 6 6 R''' R'''' Mn ~ 43,600; x ~ 40, y ~ 30, z ~ 65 Cl ( - Cross-link) Mn = 26,969, Mw = 1,087,000

7 Degradation PCA Precursors Biotic or Abiotic Degradation and/or Release of Residuals otified Substances PCAs Suspicion of CEPA Toxic Persistent! Bioaccumulative Biopersistent Increasing Presence in Arctic biota Potential Effects

8 Bioconcentration actors of PCAs in Rainbow Trout Each additional C 2 results in an ~7x increase in BC Martin et al. (2003) Environ. Tox. Chem. 22: and Martin et al. (2003) Environ. Tox. Chem. 22:

9 PS and major PCAs increased in polar bear liver during the 1990s Temporal Trend of Perfluoroalkyl Contaminants in Polar Bear Liver Samples from orth Baffin Island ( ) (Smithwick et al. 2006) D.C.G. Muir, K. Solomon, M. Smithwick et al. (2006) Environ. Sci. Technol. 40: Concentration (ng/gww) orth Baffin Bay Doubling time (years) PS 3 PA 6 PDA 5 1 PS PA PA PDA

10 An Environmental Performance Agreement with the luorocouncil (akin to the EPA Stewardship Agreement). Influx of Ss for short-chain (C6) replacement substances. or example, replacements for the four Prohibited polymers plus 40+ more substances. SAc otices imposed on these 40+ substances. A requirement for PHxA and 6-2 TH toxicity data (specifically inhalation toxicity).

11 We were supplied the following: our-week Inhalation Toxicity Study in Rats Whole body 6 hours/day, 5 days/week exposure at 0 ± 0, 1.0 ± , 10 ± or 100 ± 0.33 ppm for a total of 23 exposures Test substance was 99.7% 6-2 TH Result: EL of 1.0 ppm 1.0 ppm = 15 mg/m 3 At 1.0 ppm (15 mg/m 3) Each (6 hour) day A rat is dosed: (15 mg/m 3 x 0.26 m 3 /day) 4 x 0.50 kg = 1.95 mg/kg/day H H H H H W = g/mol

12 Rat Exposure: Inhalation rate ~ 0.26 m 3 /day Mass ~ 0.50 kg At 1.0 ppm = 15 mg/m 3 Each (6 hour) day The rat receives: (15 mg/m 3 x 0.26 m 3 /day) 4 x 0.50 kg = 1.95 mg/kg/day Human Exposure Inhalation rate ~ 23 m 3 /day Mass ~ 69 kg At ambient 300 ng/m 3 Each day (24 hours) ur human receives: (300 ng/m 3 x 23 m 3 /day) 69 kg = 100 ng/kg/day = 1 x 10-4 mg/kg/day A Margin of Exposure (ME) of ~20,000 x

13 Current SP Activities Regarding PASs Surveillance of the International Regulatory Community and engagement with the ECD Global PC Group, GSPI, PAS workshops, etcetera. Surveillance of the PAS literature for ecotox and mammalian toxicological studies showing concerns with short-chain PAS compounds. Diligent evaluation of new PASs otifications. Provide input to decisions regarding existing PASs.

14 Government of Canada Actions Regarding PASs PERLURCTAE SULATE VIRTUAL ELIMIATI ACT our fluorotelomer substances (polymers) Regulations Amending the Prohibition of Certain Toxic Substances Regulations (including PS and PA) Long-chain PCAs: Publication after screening assessment of long-chain perfluorocarboxylic acids (PCAs) that contain from 9 to 20 carbon atoms, their salts and their precursors; and Publication after screening assessment of Perfluorooctanoic acid (PA), its salts and its precursors:

15 Acknowledgements SP Health-Environment Canada PCA Team Ruben Gandia, DABT HC ew Substances (over time) Myriam Hill HC ew Substances Jackie Sitwell HC ew Substances Lorraine Tétreault HC ew Substances Andrew Beck HC ew Substances Greg Hammond EC ew Substances Bernard Madé EC ew Substances annie Lalonde EC ew Substances Thank you for your attention!