Disaster Exposure: The Four R’s

1. Disaster Exposure: The Four R’s Daniel A. Vallero, Ph.D. National Exposure Research Laboratory U.S. Environmental Protection Agency

2. Risk Assessment: Risk assessment* is a process where information is analyzed to determine if an environmental hazard might cause harm to exposed persons and ecosystems. Many decisions are made based on risk at various stages of a disaster: rescue, recovery, re-entry and re-habitation. * “Risk Assessment in the Federal Government”(National Research Council, 1983)

3. In exposure, time is of the essence… Short-term exposures can be accompanied by chronic effects….

4. Re-entry Rescue Time Time Exposure Time Time Recovery Re-habitation Time & Quality of Information to Protect Public and First Responders Vary by Stage:

5. Rescue Lesson learned: ORD part of overall team to protect public health • Portable, state of the art equipment and expertise provided to first responders • “Research” focus needs immediacy…. • Same tools often applied, but at higher levels of detection and more immediate reporting • Crime scene, forensics and rescue efforts have primacy • Responder protection is also crucial • Proper respirators and personal protection • EPA takes respirator use very seriously…. • Protocols • Very different from “environmental exposures” • e.g. levels of dioxins and benzene to protect firefighters with PPE much higher than a person without protection exposed for 30 years

6. Recovery • Somewhat more time to consider potential public exposures… • … but still working under first responder teams • Logging data and retrospectively conducting analyses • Different quality assurance needs, but still not the “typical” research design • Crime scene forensics still ongoing (defer to law enforcement), but more deliberate • In WTC, evidence moved to Staten Island • Adaptation to FEMA and other management actions • Coordination among EPA, Army Corps of Engineers, FEMA and response agencies. • Examples: • Water & wastewater treatment plant assessment • Separation of hazardous wastes

7. Re-Entry • Even more time (longer exposures) • Closer to typical research protocol, but must support local/state agencies • Benchmarks are crucial • Understandable • Allows for risk comparisons • Helps distinguish reported concentrations from reasonable exposures • EPA has protocols, but need to be tailored to each emergency • Start with applicable and relevant standards • Go to risk-based approach • Last resort: Occupational scenarios (e.g. OSHA PAL) • Then adapt • Characterize background….

8. Re-habitation • Longest potential exposures • Closest to typical metrics (e.g. lifetime average daily dose) • Conservative approaches are challenged • People and businesses want to get back to normal • Need solid reasons for denying this… • Benchmarks • Rely on State and Local to start the process • Technical approach • Background • Detection limits • Technical practicality, etc….. • Remediate to health standard or best estimate of what background was prior to accident, or….? • E.g. by proxy (may not know what it was, but use general urban background)

9. Some Key Milestones EPA has learned numerous lessons and has been improving emergency response, by: • Assessing and remediating indoor contamination caused by building collapse or other environmental disaster. • National Homeland Security Research Center developing subchronic health-based exposure advisory levels for the general public called Provisional Advisory Levels (PALs). • PALs address exposure durations of one day, 30 days, and two years for chemical contaminants detected in air or drinking water. • EPA has developed PALs for over 20 chemicals • Equates to over 360 separate values : three exposure durations, for three levels of severity and for two environmental media . • Continuing effort with the National Research Council's Committee on Toxicology to develop Acute Exposure Guidance Levels (AEGLs). • Emergency response standards applicable to the general public. • 3 levels of severity and for the durations of 10 minute, 30 minute, one hour, 4 hour and 8 hour exposures. • PALs being developed for benchmarks to bridge the gap between acute exposure durations covered by the AEGLs & the chronic lifetime exposures covered by inhalation RfCs & oral RfDs.

10. Some Key Milestones (Cont’d) • Developed a method to assess risk from exposures to contaminated building surfaces. • Will be incorporated into upcoming revision of the Risk Assessment Guidance for Superfund, Part E, Dermal Risk Assessment • Continually developing & refining scenario-driven disaster response plans on national & regional level. • Inter-agency working groups, sponsored by EPA and DHS, have developed restoration plans for large transportation infrastructures. • Produced universal templates to support generic disaster preparedness plans for various scenarios. • Supporting several inter-agency working groups developing uniform validated sampling plans, analytical methods and quality assurance protocols to support timely cleanup and restoration of infrastructures after disaster events.

11. Re-entry Rescue Time Time Exposure Time Time Recovery Re-habitation Bottom Line Exposure is critical to each phase of emergency response….

12. Contact me:vallero.daniel@epa.gov