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Society For Risk Analysis Annual Meeting 2009

Risk Analysis: The Evolution of a Science

Session Schedule & Abstracts

* Disclaimer: All presentations represent the views of the authors, and not the organizations that support their research. Please apply the standard disclaimer that any opinions, findings, and conclusions or recommendations in abstracts, posters, and presentations at the meeting are those of the authors and do not necessarily reflect the views of any other organization or agency. Meeting attendees and authors should be aware that this disclaimer is intended to apply to all abstracts contained in this document. Authors who wish to emphasize this disclaimer should do so in their presentation or poster. In an effort to make the abstracts as concise as possible and easy for meeting participants to read, the abstracts have been formatted such that they exclude references to papers, affiliations, and/or funding sources. Authors who wish to provide attendees with this information should do so in their presentation or poster.

Common abbreviations

Evolution of Health Risk Assessment, Part 1

Room: Salon A   1:30-3:00 PM

Chair(s): Rick Reiss

M3-C.1  13:30  EPA IN 1970s AND EARLY 1980s: THE DAWN OF REGULATORY RISK ASSESSMENT . Anderson E*; Exponent

Abstract: Imagine a time when there was no exposure assessment, no evaluation of dose response relations (potency), and no particular attention to mechanisms of action to define the relevance of responses in animals at high doses; a time when the science of risk assessment did not exist. This time existed when the United States Environmental Protection Agency (EPA) was created by executive order in 1970 and existed until the first federal policy to adopt the use of risk assessment and risk management was announced by the Agency in 1976 (EPA 1976, Albert et al JNCI 1977). This policy was accompanied by the first guidelines for carcinogen risk assessment (EPA 1976) and the establishment of an Agency group to carry out these assessments, the Carcinogens Assessment Group. By the time the National Research Council of the National Academy of Sciences meet to address the issue of managing risk in the federal government (NAS 1983), the EPA had conducted more than 150 risk assessments, primarily for suspected carcinogens. It was the EPA approach that was largely on trial. With the endorsement of the NAS in 1983 and the establishment of the risk assessment paradigm, risk assessment was launched. The demand for regulation was high because there was the belief that there was an epidemic of cancer and that environmental agents might be primarily responsible. The stakes were high; potential social and economic cost for a zero threshold policy to eradicate exposure to all suspect carcinogens. In the beginning, risk assessment was intended to separate those important risks from the less important ones to allow regulation to move forward. Have we come full circle to a precautionary approach that seeks to achieve much the same as the goals that preceded risk assessment? This paper will explore the early history of risk assessment and lessons that it might provide for the future.

M3-C.2  13:50  Evolution of risk assessment at U.S. EPA: 1980’s to the present. Schoeny R*; U.S. Environmental Protection Agency

Abstract: Risk assessment is generally described as an evolving science, and the experience at U.S. EPA bears out that truism. Examples from paleontological observations and evolutionary theory mirror some aspects of risk assessment development at the Agency. For example the proliferation of species in the Cambrian era (the Cambrian Explosion recorded in the Burgess shales) brings to mind the burst of guidance documents and methodologies in the post Red Book era. Likewise it can be argued that selective pressures have shaped both processes and products of risk assessment; the recent speculations regarding Homo Floresiensis and cost/ benefit analysis will be discussed in this context. Less accepted theories, such as quantum leaps in evolution, are applied to the 2005 Cancer Guidelines. And in the spirit of open scientific discourse, the theory of Intelligent Design will be introduced. The views represented in this abstract are those of the author and do not represent the policies of EPA.

M3-C.3  14:10  The Evolution of Health Risk Assessment. Southerland E*; U.S. Environmental Protection Agency, Office of Superfund Remediation and Technology Innovation

Abstract: The methodology used by EPA to assess the risks posed by contaminants at Superfund sites has changed over time to address new pathways, additional contaminants and evolving science. The basic framework for human health risk assessment in EPA's Superfund Program was established in 1989 with the release of Risk Assessment Guidance for Superfund (RAGS), Volume I, Human Health Evaluation Manual, Parts A, B and C. RAGS Part A replaced and superseded the earlier Superfund Public Health Evaluation Manual. Since 1989, our approach for addressing site-related risks has expanded to address additional pathways and additional contaminants. Additional guidance has been developed to deal with both the dermal and the inhalation pathways (RAGS Parts E and F). RAGS Part D was developed to promote a standard format for presenting risk information. Contaminant specific guidance outside of or expanding upon the RAGS Part A framework has also been developed to address radiological contaminants, lead, and asbestos. In addition, new guidance on addressing background levels, the development and use of environmental screening levels, and the use of probabilistic (as opposed to deterministic) methods of quantifying risk have been developed. In 2003 OSWER revised its hierarchy of human health toxicity values to make greater use of toxicity assessments and values which have benefitted from external peer review. My presentation will summarize the approach used by EPA to assess risk at Superfund sites, explain how it has evolved over time, and discuss the expanding role of external peer review in our development of guidance and in our use of toxicity values.

M3-C.4  14:30  History of Dietary Safety and Risk Assessment at the U.S. Food and Drug Administration (FDA) . Carrington CD*, Bolger PM; U.S. Food and Drug Administration

Abstract: A method for establishing a safe level of exposure to food additives was established by the FDA in 1954. This procedure utilized the results of tests of chemicals in rodents and safety factors that were partly justified as a matter of policy. Although this methodology has evolved and is used for applications other than food additives, these safety assessment procedures still share some common characteristics. In particular, a) it is presumed that the risk from a chemical will be managed by exposure to a specified level, b) some aspects of the procedure are justified as a matter of policy, c) there is no formal statement of risk at any level of exposure, and d) toxicologists are largely responsible for determining the level that will be considered safe. Risk assessment methods, which began to be used approximately twenty years later, were initially used to evaluate both additives and unintentional contaminants that were considered to be carcinogenic. Unlike the safety assessment procedure, a risk assessment generated an estimate of the probability of harm, and as a result, left more discretion to risk managers in selecting a level of exposure that would be considered tolerable. However, because cancer assessment procedures were designed to be “conservative” or worst-case, they inherently contained an uncertainty-management aspect that was justified as a matter of policy. Over the past twenty years, the FDA has employed risk assessment procedures to evaluate certain contaminants in food that are a) not carcinogenic, b) difficult to avoid or control to a specified level, and c) have exposures that would not be acceptable for food additives. Contaminants that fall in this category include metals, mycotoxins, and environmentally persistent industrial contaminants. For such an assessment it is important to clearly differentiate between the scientific and policy aspects of each assessment which requires a formal uncertainty analysis.

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