Final Program - Society for Risk Analysis

methods used by FDA and EPA to evaluate drug and chemical toxicity in humans inorder to foster rigor and transparency in regulatory decision making. We will brieflydescribe existing data on US population exposure to commercial chemicals, pesticides,human and veterinary drugs. We will compare toxicity assessment proceduresfor these chemical types through document review and interviews with Agency personnel.We will present project findings and recommendations for a unified set ofprinciples for safety evaluation of substances.P.7 Nakanishi J, Gamo M, Ema M, Ogura I, Kobayashi N; j-nakanishi@aist.go.jpAdvanced Industrial Science and Technology (AIST)PROPOSAL FOR AN OCCUPATIONAL EXPOSURE LIMIT OF CAR-BON NANOTUBES BASED ON THEIR RISK EVALUATIONThe risk evaluation associated with carbon nanotubes (multi-, double- and single-walled)was carried out for the purpose of deriving the occupational exposurelimit (OEL) and making a model framework to assess risks from emerging technology.The OEL is derived from rat toxicity studies including inhalation exposure testsand intratracheal instillation tests in which the inflammation is taken as a toxicityendpoint, and biokinetic study of retained carbon nanotubes (CNTs) in the rat lung.To obtain the general biological effects caused by CNTs, various simplified tests andestimation methods were applied. Among them, the most representative one is thebiaxial approach. Using this approach, we revealed that the biological activity due toCNTs is strongly dependent on their BET specific surface area irrespective of multiwalled,double-walled or single-walled CNTs. In other words, the distinction of multiwalledCNTs from single-walled CNTs is not significant. Therefore, we proposedone value of OEL of 0.03 mg/m3 irrespective of CNT classification, which shouldbe applied according to the specific surface area of CNTs.In addition, we examinedand discussed the possible causal relationship between cancer and CNT exposure.Although we cannot arrive at a distinct conclusion at present, the experimental resultswe have obtained to date are consistent with our working hypothesis that CNTexposure increases the incidence of cancer after prolonged severe inflammation dueto massive exposure. Considering such situation, we proposed the OEL as a periodlimitedone for about ten years, which should be reviewed after about ten years, andwrote it in the notation of OEL(PL).P.70 Nakayachi K; nakayachi@mail.doshisha.ac.jpDoshisha UniversityTRUST IN ORGANIZATIONS RELEVANT TO THE TOHOKU EARTH-QUAKE AND TO THE CRISIS AT THE FUKUSHIMA DAIICHI NUCLE-AR POWER PLANTThe Tohoku Earthquake caused over 15,000 deaths, and more than 8,000 arestill missing. It also caused the ongoing crisis at the Fukushima Daiichi nuclear power150plant. The massive damage resulting from the earthquake and the chaos caused by thepower plant crisis seemed to destroy the public’s trust in the risk managers relevantto these issues. The purposes of this study are to clarify the levels of public trust inthe organizations relevant to the issues and to examine the primary factors definingthe levels of trust. One thousand and thirty adults in Japan participated in the survey.They were asked to evaluate their trust in, value similarity to, competency of, andmotivation of six organizations using three items for each factor on five-point Likertscales. The results of the mean ratings showed that the least trusted organizationwas Tokyo Electric Power Company (TEPCO), which runs the Fukushima Daiichinuclear power plant, followed by the Nuclear and Industrial Safety Agency (NISA),which is responsible for the administration of nuclear safety issues. The MeteorologicalResearch Institute, which is the national agency studying the tsunami forecast wasrated the highest of the six, followed by the East Japan Railway Company, which wasforced to suspend operations, causing millions to have to walk long distances home.The Earthquake Research Institute of the University of Tokyo and the Food SafetyCommission were in the middle. Intuitively, the expectation would be that TEPCOand NISA lost public trust due to the lack of competency in resolving the accident.The results of structural equation modeling revealed, however, that their path coefficientsfrom value similarity to trust were the greatest of the six. The negative correlatebetween the mean trust and path coefficients in the organizations was extremely high.The implication of the findings is clear: The more trust is destroyed, the more valuesimilarity matters.P.59 Nance P, Haber L, Maier A, Patterson J; nance@tera.orgToxicology Excellence for Risk AssessmentSHIPWRECKED: FINDING THE LIFE RAFT OF KNOWLEDGE FORRISK ASSESSMENTRisk assessment is comprised of a diverse sea of experts. While certain areas ofexpertise may be emphasized for different issues or applications, the effective applicationof risk assessment to aid in problem solving and decision making is a multidisciplinaryeffort. While experts may be familiar with multiple aspects of the NationalAcademy of Sciences risk assessment paradigm, no one person can be an expertin all relevant areas. Therefore, collaboration among people with complementaryexpertise can often provide added value in risk assessments. The NAS (2009) frameworkillustrates the diversity of knowledge needed for a purpose-focused risk assessment.In addition to hazard characterization, dose-response assessment, exposureassessment, and risk characterization, the framework highlights the importance ofproblem formulation, risk communication, and decision analysis. Consideration ofthe framework and underlying issues allows the identification of key knowledge areasfor different aspects of the risk assessment paradigm. Using the NAS risk paradigm,an educational model was developed to allow risk assessors to assess their knowledgebase and construct a curriculum to better fit their needs in risk assessment.