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May 20 , 2005. Environmental Health. Issues and Priorities in the Pacific Northwest. Robert Duff Director Office of Environmental Health Assessments Washington State Department of Health. Highline Community College – Tacoma, WA. Comparative Risk Projects. EPA and states
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May 20 , 2005 Environmental Health Issues and Priorities in the Pacific Northwest Robert Duff Director Office of Environmental Health Assessments Washington State Department of Health Highline Community College – Tacoma, WA
Comparative Risk Projects • EPA and states • US EPA in 1987 issued Unfinished Business: A Comparative Assessment of Environmental Problems • Regions and states followed • Highest ranking issues • Indoor air • Outdoor air • Others • Lead, pesticides, food
Non-cancer RiskCancer Risk Response Threshold No Threshold Type of Result Yes/No Probability Risk Assessment Methods
Non-Cancer Assessment Threshold RESPONSE “Safety Factors” DOSE Health benchmark
Non-cancer RiskCancer Risk Response Threshold No Threshold Type of Result Yes/No Probability New guidance moving toward a more qualitative approach that acknowledges thresholds Assessment Methods
Cancer Assessment Measurable Range (Epidemiology or Animal Study) 500 in 10,000 # of Cancers Threshold? 1,000 in 10,000 100 in 10,000 50 in 10,000 Predicted Range (Risk Assessment) DOSE
Challenges - Uncertainty • Exposure • Models versus measurement • “Background” • Toxicity • Cancer – low dose extrapolation • Mixtures • Endocrine disruption • Environmental justice
Challenges - Background Exposure • EPA is not calculating an RfD (Reference Dose) for dioxin….. • “Any RfD that the Agency would recommend under the traditional approach for setting an RfD is likely to be 2-3 orders of magnitude (100-1,000) below current background intakes and body burdens. Because exceeding the RfD is not a statement of risk, discussion of an RfD for an incremental exposure when the RfD has already been exceeded by average background exposures is meaningless.”
Major Issues in the Pacific Northwest • Persistent, bioaccumulative toxics (PBTs) • Fish consumption advisories • Area-wide soil contamination • Arsenic and lead
What are Persistent, bioaccumulative toxics (PBTs)? • Polychlorinated biphenlys (PCBs), methyl mercury, organochlorine pesticides (DDT, chlordane), dioxin, polybrominated diphenyl ethers (flame retardants) • Build-up in our environment and our bodies • Slow to breakdown in the environment • Uptake exceeds elimination rate • Often store in fat (not methylmercury) • Also known as POP’s
Why are we concerned? • Recent fish consumption studies show in utero exposure results in developmental problems • PCBs and methylmercury • Learning and behavior deficits • PBDEs – flame retardants • Similar effects in animal studies
What is a fish advisory? • General advice • Choosing fish with lower contaminant levels • Cooking and preparation • Variety • Meal limits • Generally bounded by upper and lower limits for effectiveness • 4, 2, 1, 0 meals/month • EPA guidance
What is a fish advisory? • Species specific • Most advice is broken down by species • Surrogates can be used for trophic levels • Water body specific • Hazardous waste release or just a lake that was sampled? • DOH currently has 14 water body specific advisories • Statewide advice • Mercury
Who are we trying to protect? • High-end consumers • Native American tribes • Asian and Pacific Islander communities • Women of child-bearing age and children • Clearly a concern for the developing fetus • PCBs and mercury • Flame retardants, dioxin? • General population • For PCBs not mercury • No consensus on mercury effects in adults • Blood pressure
Key Messages • Eat fish, Be smart • Fish are good for you • Omega-3 fatty acids • Moving away from “limit, limit, limit” • Provide info so consumers can eat heart health 2 meals/week - American Heart Association • Most people do not eat 2 meals per week • Many choices are safe to eat at this rate
Key Messages • Work with high consumers • Tribes, Asian Pacific islanders communities • Benefits of more than 2 meals per week likely still outweigh risks • Cutoff???? • What are we doing to get/keep PBTs out of our food web???
Communication is Key From Oregon – Portland Harbor/Willamette River Presentation – D. Stone
Global Efforts to reduce PBTs • International • Persistent Organic Pollutants • Stockholm Convention • Europe • REACH • Registration, evaluation and authorization of chemical products • Precautionary principle
Global Efforts to reduce PBTs • US EPA • Toxics Substances Control Act (TSCA) • PBDE Significant New Use Rule • Clean Air Act • Mercury • Washington • PBT Initiative • Mercury, flame retardants - PBTs
Area-wide Soil Contamination • Arsenic (As) and lead (Pb) in Washington State • Old orchard lands • Tacoma smelter plume • Everett smelter • Northport smelter
Area-wide Soil Contamination • Orchard lands not well characterized • Spraying was sporadic • GIS with aerial photography • Identifying old sites • Targeting both sampling and education
Vermiculite - asbestos • Libby, MT • background • Vermiculite • Contained high-levels 30-50% asbestos (tremolite) • Direct link to health effects • Nationwide problem • Exfoliation facilities • Attic insulation
Vermiculite - asbestos • Agency for Toxic Substances and Disease Registry • Medical screening • Nationwide follow-up on over 200 sites • 28 priority sites including one in Spokane and Portland • National Asbestos Exposure Review • EPA cleanup of site and homes in Libby ongoing
Pleural Findings – All Views Interstitial - PA View Exposure Class n Normal Abnormal Normal Abnormal No Apparent Exposure 122 116 (95%) 6 (5%) 121 (99%) 1 (1%) 1-3 Exposure Pathways 1569 1394 (89%) 175 (11%) 1559 (99%) 10 (1%) 4-5 Exposure Pathways 1488 1262 (85%) 226 (15%) 1471 (99%) 17 (1%) 6+ Exposure Pathways 2411 1824 (76%) 587 (24%) 2390 (99%) 21 (1%) Vermiculite - asbestos Total 5590 994 (17.8%) 49 (0.9%) Background 0.2 to 2.3 %
Vermiculite - asbestos • Legislation • Liability and compensation • Ban – Sen. Murray • Asbestos is not banned in the US • US District court overturned EPA ban of most uses in 1990 • Future activities - EPA and ATSDR • Assess 28 exfoliation facilities across US • Address vermiculite in attic insulation