|
|
Replacing Default Values for Uncertainty Factors with
Chemical Specific Adjustment Factors: Reducing Uncertainty in
Noncancer Risk Assessment
|
|
A tutorial
workshop Society
for Risk Analysis Annual Meeting Risk007: Agents of AnalysisDecember 9-12, 2007 — San Antonio, Texas
PRE-REGISTRATION DEADLINE IS November 9, 2007 Replacing Default Values for Uncertainty Factors with Chemical Specific Adjustment Factors: Reducing Uncertainty in Noncancer Risk Assessment (organized by Dr. Lynne Haber). SynopsisThe World Health Organization, through the International Programme on Chemical Safety (IPCS), has established guidance on the use of mechanistic data to replace default uncertainty factors for interspecies extrapolation and intraspecies variability in deriving risk values such as Reference Doses (RfDs) and Tolerable Concentrations (TCs). This guidance informs the choice and application of data that can be used to replace defaults with chemical specific adjustment factors (CSAFs), resulting in values that better reflect the data for the chemical of interest. Under the CSAF framework, the uncertainty factors for interspecies differences (UFA) and human variability (UFH) are first subdivided into toxicokinetic (TK) and toxicodynamic (TD) components. The data relevant for each subcomponent is then evaluated to determine whether chemical-specific data can be used in place of the default. Use of the CSAF framework allows the improved use of available data in deriving risk values, and can assist in targeting new studies to address uncertainties and lead to more accurate risk values. CSAFs have been used by the U.S. EPA in deriving an RfD for boron and by Health Canada in deriving a TC for 2-butoxyethanol. This half-day workshop will provide a brief review of the use of uncertainty factors and historical perspective on the reliance on quantitative data to develop values for inter- and intraspecies extrapolation. The course will focus on the IPCS methodology for CSAF development, including the thinking process and steps used for evaluating data. Examples and classroom activities will be used as instructional aids. Course Overview and Goals:
Dr. Lynne Haber has 14 years of experience in developing human health risk values for a variety of government agencies and private sponsors, and in research related to risk assessment methods. She is the Research Program Manager at Toxicology Excellence for Risk Assessment (TERA). Her interests include the improved use of mechanistic data in risk assessment, including incorporation of mode of action data in cancer risk assessment, and use of data to replace default uncertainty factors. She has been the lead author, coauthor, or reviewer of dozens of detailed assessment documents. She has served as a panel chairperson or panel member for scientific peer reviews organized by TERA, EPA, and other U.S. and foreign government agencies. She has also served on two panels for the NAS/NRC. Lynne is active in communicating her findings to the broader scientific community through participation in professional societies, teaching courses in risk assessment methods, routine publication of her work, service as an editorial reviewer for scientific journals, and through presentation of invited lecturers. Her published work includes lead authorship of the chapter on noncancer risk assessment (including dose-response modeling methods) for Patty’s Toxicology, and an invited review on the use of mechanistic data in risk assessment. She was also the coauthor for an analysis of the effect of genetic polymorphisms on human variability in dose, using PBPK and Monte Carlo modeling. She has published on methods for deriving occupational exposure limits, and on incorporating toxicokinetic data into risk assessment. She served as vice president and councilor of the SRA Dose-Response specialty group and as an officer of the SOT Risk Assessment Specialty Section (RASS), is a Diplomate of the American Board of Toxicology. Ms. Bette Meek has a background in toxicology and extensive experience in assessment and the management of chemical assessment programs within the Government of Canada. She is currently on interchange from Health Canada to the University of Ottawa for a two year period, where she has been appointed the Associate Director of Chemical Risk Assessment in the McLaughlin Institute of Population Health. Bette’s most recent experience involved developing and implementing process and methodology for the health assessment of Existing Substances under the Canadian Environmental Protection Act (CEPA) including the precedent setting mandate to categorize and screen priorities from among the 23,000 substances included on the Domestic Substances List. Prior to managing the Existing Substances program, Ms. Meek managed assessment programs for contaminants in drinking water and air. With colleagues within Canada and internationally, she has contributed to or led initiatives to increase transparency, defensibility and efficiency in health risk assessment having convened and participated in initiatives in this area for numerous organizations including the International Programme on Chemical Safety, the World Health Organization, the International Life Sciences Institute, the U.S. Environmental Protection Agency, the U.S. National Academy of Sciences and the U.S. National Institute for Environmental Health Sciences. Specific areas of focus have included development of analytical frameworks for weight of evidence for mode of action, increasing incorporation of biological data in dose-response analysis and refining models of peer input, consultation and review. She has also authored over 150 publications in the area of chemical risk assessment and received several awards for contribution in this domain. Dr. Andy Maier has 13 years of professional work experience in the areas of environmental health, occupational hygiene, and toxicology. He currently serves as the Associate Director for the non-profit organization Toxicology Excellence for Risk Assessment (TERA). In his capacity as a toxicologist and risk assessor, he has led numerous projects, and has co-authored technical reports, human health risk assessment documents, or toxicity summaries covering more than 100 individual substances for government and private industry sponsors, including comprehensive documents for derivation of RfDs, RfCs, and cancer risk assessments. He has evaluated toxicokinetic and toxicodynamic issues surrounding the issue of uncertainty factor selection for many of these assessments, and served as a commenter on the IPCS chemical-specific adjustment factor methodology. Dr. Maier completed his Ph.D. in toxicology from the University of Cincinnati with research interests in molecular mechanisms of toxicity. He continues to be actively engaged in developing research to improve risk assessment approaches through the integration of basic biology and risk assessment science, including on methods and approaches for using early biological effect markers to reduce uncertainties in risk assessment. Dr. Maier remains active in communicating his findings to the broader scientific community through participation in professional societies (including serving as part president of the Ohio Valley SRA Chapter), routine publication of his work, service as an editorial reviewer for scientific journals, and through presentation of invited lecturers. He has served in several capacities in support of scientific peer reviews and workshops, including serving as facilitator for a peer consultation panel charged with evaluating a framework for evaluating age-dependent differences in tissue dosimetry. He is a Diplomate of the American Board of Toxicology. The pre-registration fee is $225. After the deadline, the registration is $250. You do not need to register for the Annual Meeting to attend the workshop. There is a $50 discount if you also register for WK2, on mode of action. (See http://rsi.ilsi.org/Projects/RFSRA.htm). To register, go to the SRA website at http://www.sra.org/events_2007_meeting.php and either register online or print out and submit the registration form. PRE-REGISTRATION DEADLINE IS NOVEMBER 9, 2007 More InformationMore information can be obtained from Dr. Lynne Haber haber@tera.org, telephone 513-542-7475 ext. 17, fax 513-542-7487.
Click here for more information about TERA Training. |
Last updated: 10/09/2007