Adherence to the Scientific Method while Advancing Exposure Science Daniel A. Vallero, Ph.D U.S. Environmental Protection Agency National Exposure Research Laboratoy

Scientific method Science is more than inquisitiveness and explanation of the world around us…. “When we explain something, as science strives to do, we gain, or at least attempt to gain, power over that entity. Understanding how a molecule is structured allows for efficacious medicines and treatment of cancer. “Indeed, the basic scientist may see ‘control’ and ‘power’ as motivators for all science….” “One of the principal values of the scientific method is that the process is aboveboard and objective. It encourages scientists to be careful to guard the public trust.”

Scientific method (cont’d) Beware of “settled science” “Indeed there can be arguably some level of consensus, but nothing near unanimity in any scientific discipline especially when the underlying theory is still evolving and the uncertainties still need to be reduced by experiment and observation. Indeed, the thoughtful scientist must ask what exactly is supposed to be ‘settled’.” Compare this to CP Snow: “The only ethical principle which has made science possible is that the truth shall be told all the time. If we do not penalize false statements made in error, we open up the way, don’t you see, for false statements by intention. And of course a false statement of fact, made deliberately, is the most serious crime a scientist can commit.”

Exposure science So, where does that leave us in advancing exposure science? Adapted from: D.E. Stokes (1997). Pasteur’s Quadrant. The Brookings Institution, Washington, DC Domain of exposure science?

Risk is a function of hazard and exposure Hazard Identification Dose Response Assessment Exposure Assessment Risk Characterization Source Characterization Risk Management Decisions Lioy: No contact, no exposure….. Risk Management Options ID’d Risk Management Options Cost and Effectiveness Assessment

Disaster Preparedness & Response Disaster -> Low-probability events with high-value consequences Disruption of Normal Conditions Human suffering and/or property damage Exceeds the capacity of the affected community to respond without outside resources.

Disaster Preparedness & Response Disaster -> Low-probability events with high-value consequences Disruption of Normal Conditions Human suffering and/or property damage Exceeds the capacity of the affected community to respond without outside resources. So then, when does a “problem” become a “disaster”?

Disaster Preparedness & Response When risks that are not properly managed result in significant physical damage to human life, ecosystems, and materials.

Disaster Preparedness & Response Thus, decision makers must consider human and environmental vulnerability. This can prevent or minimize the probability of accidents, reduce the consequences, allow for disaster control, and take steps to mitigate when accidents occur. Disasters have the potential to cause global, long- term, and even irreversible impacts.

Disaster Preparedness & Response Disasters vary in scale and complexity Have the potential to cause global, long-term, and even irreversible impacts. Harkens of the precautionary principle.

Species Extinction Climate Change Stratospheric Ozone Depletion Accidents can lead to global radioactive impacts, global human losses, multi-generational impacts, invasive species, and species extinction Global Spatial Scale Persistent Bioaccumulative Toxins Regional Acidification Smog Particulate Impacts Air Toxics Fossil Water Aquifer Depletion Ecotoxicity Local Microenvironmental exposures Centuries Hours Years Temporal Scale Accidents relative to other environmental issues. Some accidents (and their indirect effects) have the potential to cause global, long term (even irreversible) impacts.

Exposure Science Needs vary by stage. Sampling and analysis approaches vary. Varies by who needs protection. Quality of science depends on time. But, health decisions are often based on insufficient and misleading information.

Information Problems Increase as the magnitude of the event unfolds and the severity of the of the event becomes more apparent Affected by amount and quality of the data and interpretation of the data Limited communication, especially in early stages– short wave radio (in worst and largest events) to wireless and web based systems Surveillance after an event starts as soon as possible and cycles as time and data becomes more readily available Information quality affects operational decisions

Exposure needs vary by stage: Rescue Recovery Re-entry Restoration Re-habitation

Improvements Automated equipment tracking system Rapid response team Improved portable and flexible emergency response platform and personal monitors Improved and new sensor technologies Revisions to national contingency plans Beginning to adapt occupational exposure standards to environmental conditions (e.g. PELs, AEGLs for communities) Established indoor and ambient clean up protocols Better communication devices (less reliance on land lines) Computational methods National Decontamination Program’s simulations. However, this needs to be expanded substantially to numerous communities and for various types of disasters

Rescue Basic measures to preserve life and function Triage –essential in large disasters – Field stabilization Portable, state of the art equipment and expertise provided to first responders (US Coast Guard, Homeland Security, Regional Superfund Response Team) “Research” put on hold 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 utmost importance Proper respirators and personal protection Protocols Very different from “environmental exposures” (e.g. levels of dioxins and benzene to protect firefighters with PPE are much higher than a person without protection exposed for 30 years)

Recovery Somewhat more time, 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 Police, FBI and Homeland Security), but more deliberate - In WTC, evidence moved to Staten Island Adaptation to FEMA and other management actions - In Katrina, U.S. Army Corps of Engineers proposals (e.g. possible exposures to asbestos from cleanup options versus exposures from waiting…)

Re-Entry Even more time Closer to typical research protocol, but must not hinder local and Regional Office activities and decisions Region 2 made decision to require HazMat level of cleanup before re-entry Benchmarks are crucial Understandable Allows for risk comparisons Helps distinguish reported concentrations from reasonable exposures.

Benchmarks Use identified guidelines/standards where available In WTC Response: AHERA school re-entry standard for airborne asbestos OSHA/EPA definition of ACM for bulk material NAAQS for ambient air sampling (Pb, CO, PM2.5) in residential areas OSWER residential guidelines for dioxin, PCBs and lead in dust/bulk material OSHA PELs (TWA) for air samples taken on the debris pile (worker exposure) Federal Ambient Marine Water Quality Criteria and historical Hudson River data Federal MCLs for drinking water samples NPDES permit limits

Benchmarks When identified guidelines/standards absent: Developed risk-based screening levels E.g. for residential scenario used EPA Hazard Evaluation Handbook (1 & 30 year exposure for carcinogens) Example for dioxin: 30 year screening value for ambient air: 0.0054 ng/m3 1 year screening value for ambient air: 0.162 ng/m3 Similar approach used for air values for PCBs, benzene, other VOCs, semi- volatile compounds, and metals Compare to background (e.g. annual NAAQS and air toxics measurements at nearby sites)

Challenge of benchmarks Without benchmarks Fail to grasp a real environmental problem that exists Perceiving a problem even when things are better than or do not differ significantly from those of the general population.

Avoiding false negatives: What if measurements indicate no harm, but in fact toxic substances are in the air we are breathing? What if this substances that have been identified really do cause cancer but the tests are unreliable? What if people are being exposed to a contaminant, but via a pathway other than the ones being studied (e.g. exposed to volatile

Avoiding false positives: What if previous evidence shows that an agency had listed a compound as a carcinogen, only to find that new information is now showing that it has no such effect? May force public health officials to devote inordinate amounts of time and resources to deal with so-called “non-problems.” Erroneously scare people about potentially useful activities (e.g. cleaning up debris) Create credibility gaps between engineers and scientists and the decision makers. I In turn the public loses confidence in public health agencies.

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… Benchmark? Something like the “residential standard” from Superfund? Remediate to a level as if accident never occurred?

Restoration Restoring normalcy Even enhancing to improve resilience to address next “problem” and to prevent future disasters Resilience in humans is analogous to ecosystem resilience.

LCA is another promising tool Need to use a systems perspective with a holistic approach to broaden the range of impacts included in environmental decision making. LCA is typically one of the most comprehensive tools, attempting to prevent unknowingly shifting pollutants, damages, and resource uses; but assessments typically don’t quantify disasters. (Areas of Protection paper). Need to be comprehensive, but data and models are sometimes not available to allow quantitative predictions and there are multiple sources of uncertainty.

Quantitative methods can be expanded to include impact categories of interest to communities Social Impacts LOCALLY SITE SPECIFIC Water Use Human Health Criteria Pollutants Global Climate Change Ozone Depletion Eutrophication Human Health Non Cancer Smog Formation Fossil Fuel Use Acidification Ecotoxicity Rare Earth / Mineral Use Human Health Cancer SITE SPECIFIC POPULATION SPECIFIC Characterization Modeling Land Use MORE CERTAIN LESS CERTAIN Economic Impacts MORE CONSENSUS LESS CONSENSUS Employment Occupational Health Pathogens Accidents How much time and effort should go into developing the individual models that could be included? Localized Exposures Landfill Leaching Figure adapted from: Bare, J. LCA 101 - Life Cycle Impact Assessment Webinar - http://my.brainshark.com/LCA-101-Life-Cycle-Impact-Assessment-2011-Aug-14-630457314

Conclusions Recent and current disasters indicate that we continue to be surprised and ill-prepared However, we now have tools and capabilities that are far better than before WTC. We just need to use them more effectively.

Contact me: vallero.daniel@epa.gov