Final Program - Society for Risk Analysis

iomonitoring “equivalent” level; the CDC guidance value of 10 µg/dl blood lead.However, for most other substances comparison values are expressed in external exposuremetrics. If health assessors are provided with biomonitoring data they mustturn to the scientific literature to find a study that reports health effects at a similarlevel or must estimate the exposure that occurred in order to have a comparable metric.ATSDR has begun to enhance the health assessor’s understanding of adversehealth risks in the community by employing computational methods to improve toxicityand exposure data. One of the more promising computational methods is theuse of PBPK modeling for estimation of internal dose. Recently PBPK modelinghas been used in a reverse dosimetry manner to estimate exposure given a biologicallevel measured in the community. In addition, biomarkers of exposure and effect arebeing used to compare to national averages as identified in the NHANES data set.While such a comparison does not assure that the national average is at a no-effectlevel, such comparisons provide insight into the magnitude of the exposure. Neithertechnique is being used by ATSDR to exclusively provide conclusions about publichealth; however such analyses stand as a strong adjunct to assessments performed intraditional manners. This presentation presents two sites where ATSDR has used acombination of PBPK modeling and biomonitoring to help assess health risks fromexposure.M4-G.1 White RH; rwhite@jhsph.eduJohns Hopkins UniversityAN OVERVIEW OF CARBON NANOMATERIAL TOXICITY RE-SEARCHEfforts to assess the risks of carbon nanomaterials has resulted in an expandingthough still limited body of scientific data on the toxicity of these emerging materials.To date, published toxicity studies have utilized whole animals and cells, with no humandata currently available. This presentation will provide an overview of selectedcarbon nanomaterial toxicity data and provide an introduction to the challenges inassessing the human health risks of carbon nanomaterials.T4-F.3 Whitfield S, Anthony R, Lanthrum G; scwphd@hotmail.comNational Security Programs InScope International, Institute for Defense Analysis, RAMTASCVALUE ORIENTATINS, RISK PERCEPTION, AND INSTITUTIONALTRUST-DRIVEN POLICY DILEMMAS IN THE NUCLEAR WASTEARENA: TOWARD A PROCESS FOR FORECASTING AND AVOIDINGPOLICY GRIDLOCKThe history of the institutional processes for developing a geologic repositoryfor high-level nuclear waste has been a poster child for expensive and time-consumingpolicy gridlock. A large body of empirical data suggests this gridlock has been heavilyinfluenced by differences in risk perceptions, values, and trust in the decision-makingprocess. Whitfield et al developed and tested a model of value orientations, risk perception,and institutional trust suggesting that support for nuclear waste management(NWM) was predictable based on underlying value orientations. This paper builds onthese prior findings by showing how attempts to satisfy all relevant values inevitablylead to a plethora of policy dilemmas, each threatening to discredit the institutionalprocess charged with NWM. Anthony has shown that most policy dilemmas can beanticipated and that once recognized suggest options for avoiding those dilemmasand cultivating trust in the institutional process. Perhaps the most fundamentalpolicy dilemma among the many facing NWM has been the “not to fail” mandate toisolate existing nuclear waste from the environment. This mandate dictates that if anydeficiency comes to light due to a real problem or controversy among stakeholderviews, NWM attracts negative attention and credibility suffers. If however there areextended periods without visible problems, real risks are liable to be eclipsed by thepressures of cost, schedule, and general complacency until a real deficiency is induced.A possible option for transforming this lose-lose game into win-win effort isto focus the design of the institutional process on identifying and tracking indicatorsexpressing the day-to-day balance of the risks of taking versus not taking action. Weillustrate how identifying policy dilemmas in advance can be usefully applied to onepossible future aspect of NWM, the implementation of interim storage for spentnuclear fuel away from commercial nuclear reactors.T3-I.4 Wiener JB; wiener@law.duke.eduDuke UniversityRISK-RISK TRADEOFFS IN CLIMATE ENGINEERINGThe risk of potentially catastrophic climate change, and the cost of greenhousegas (GHG) emissions abatement, have spurred interest in techniques for engineeringthe climate through solar radiation management (SRM), such as injecting reflectiveparticles into the upper atmosphere. Such geoengineering projects may pose risk-risktradeoffs, which might include, for example, excessive global cooling; moral hazardundercutting GHG abatement; pollutant deposition; adverse regional and distributionalimpacts; and abrupt warming if SRM were discontinued while GHG concentrationsremain high. Sound decisions will depend on evaluation of these risk-risktradeoffs and a search for risk-superior options. Recognizing these risks, some haveadvocated international governance strategies to restrain hasty deployment of SRM,because there may be incentives to be the first mover in deploying SRM (the converseof incentives to free ride in emissions abatement). And some have advocated researchon SRM in order to understand it better, reduce the risks of hasty deploymentin a crisis, and assist in the selection of the best (lowest overall risk, highest net benefits)option. But such research may pose its own risk-risk tradeoffs, because researchon SRM might lower its costs and/or clarify its regional distributional impacts, eitherof which may exacerbate the race to deploy first. Lower cost, typically viewed as anadvantage of SRM over GHG abatement, may encourage unaccountable states or193