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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

Risk Analysis for Microbial Exposures in Agricultural Workers Sponsored by BSSG

Room: Homeland   3:30-5:10 PM

Chair(s): Frank Hearl

W4-F.1  15:30  Occupational Exposure Limits: Regulating Exposures to Microbial Agents. Hearl FJ*; National Institute for Occupational Safety and Health

Abstract: Workers are exposed on the job to a myriad of chemical substances, biological agents, physical agents, and other stressors, often in combination, that may create or increase the risk of death or serious physical harm. Established occupational exposure limits (OELs) are often used to guide risk management decisions for engineering controls, personal protective equipment or other means of exposure control. Agricultural workers, among others are often exposed to complex mixtures of agents such as toxic gases, vapors, dusts and mists, pesticides, and biological materials including pathogens that do not have established exposure limits. Strategies beyond reliance on OELs are needed for risk assessment and risk management decisions. When OELs are available, measured exposure may be scaled using the severity index (Concentration / Exposure Limit), and summed assuming additivity for mixtures of such agents. Without OELs, such as for viable microbial agents, e.g. mold, bacteria and virus, it is not possible to use the quantitative algorithm described above based on the severity index. Instead other methods are used based on professional judgment and epidemiological experience. To cope with the uncertainties in the absence of exposure limits and with novel exposure situations, occupational health professionals have developed various systems for risk management such as control banding to provide a logical rubric for exposure control based on the amounts of materials present, the probability of those materials resulting in exposure, and the relative toxicity of the agent.

W4-F.2  15:50  The Animal Human Interface in Food Animal Production. Silbergeld EK*, Feingold B, Jeibler J; Johns Hopkins Bloomberg School of Public Health

Abstract: With increasing concern over pandemic influenzas of animal origin, there is an urgent need to develop evidence-based programs to reduce the evolution of viral strains that are transmissible to humans and capable of causing severe illness. Workers in food animal production are at the front line of exposures to these zoonoses and the population at greatest risk of primary exposures and infections. Although most attention has been given to smallholder animal husbandry, risks of viral evolution and transmission to workers are heightened in industrial scale food animal production (IFAP) for these reasons: IFAP involves dense confinement of animals under stressful and nonhygienic conditions; animals are exposed to subtherapeutic doses of antibiotics as feed additives; most workers are not provided cleanup facilities or personal protection; and waste management is largely unregulated. We are developing a model to evaluate factors contributing to spread of influenzas among farms in regions with high IFAP densities. These factors include: farm size, existence of producer networks, frequency of vehicle and social contacts. We wil use spatial statistics and geographic information systems to develop risk maps useful in guiding monitoring programs and developing interventions to protect workers. A major area of uncertainty in understanding occupational risks of influenza exposure concerns workers in meat and poultry processing plants. Because of the size of this workforce and its lack of access to medical and other social services in the US (due to immigration status as well as the use of incarcerated persons who are at additional risk of infection in prisons), this question is of high priority. Research supported by NIOSH, Center for a Livable Future, Winslow and Clayton Baker Foundations, and the Pew Charitable Trusts.

W4-F.3  16:10  Microbial pathogens in the Environment:A hydrologicalaspect of Manure-Borne Pathogen Transport. Doe JB, Roodsari Reza*; USDA

Abstract: Land application of manure is recommended to recycle organic matter and nutrients, thus enhancing the soil quality and crop productivity. However, pathogens in manure may pose a human health risk if they reach potable or recreational water resources. In addition, lack of understanding of land topography and soil structure, and the dynamics of the precipitation for some farmers may stagnates contaminated runoff with pathogenic agents in a depression to further extend the risk zone to human, animal, and environment. Functional relationships between environmental parameters such as soil, topography, vegetation, rainfall dynamics, and pathogen transport enable us to integrate fate and transport information with the best management practices to improve and validate pathogen transport/dispersal models; propose methods to reduce or eliminate pathogen transport and to minimize the public health impacts of food borne.

W4-F.4  16:30  Calibrating Risk Assessments: The Role for Cost-Benefit Analysis. McLaughlin CF*, Hearl FJ; US Food and Drug Administration- Center for Food Safety and Applied Nutrition

Abstract: Microbial risk assessment is a popular way to objectively evaluate risks to public health. However, risk assessment numbers alone can convey a false sense of accuracy. Without integrating risk assessments and economic analyses, finite resources may be allocated to reducing an already low risk, while higher risks may continue to be tolerated. Cost Benefit (CB) Analysis is useful in helping policy makers evaluate health and safety policies. However, CB analysis carries considerable controversy, especially because it provides ways to measure health, safety and the environment in monetized terms. This paper will present a simple approach to integrating economics and risk assessment in estimating public health benefits from occupational hygiene and sanitation interventions in farms. Occupational field sanitation standards not only protect the workers from illness, but reduce the potential for contaminating products such as fresh produce which, if consumed by the public, could cause a large number of illnesses. In this context, this presentation will address different health valuation approaches such as direct cost of illness to estimates that includes society’s willingness to pay (WTP) or Value of a Statistical Life Year (VSLY), Quality Adjusted life years (QALY’s) and disability adjusted life years (DALY’s).

W4-F.5  16:50  Economic Incentives for Intervention. Pana-Cryan R*; CDC NIOSH

Abstract: A holistic, anticipatory approach to issues affecting worker safety and health naturally leads to consideration of a systems approach to safety and health. A system is defined as an integrated composite of people, processes, and products that satisfy a stated need or objective. Through such an approach, environmental risks, product and service quality risks, and occupational safety and health risks are eliminated or minimized throughout the entire life cycle of the system, focusing on its effectiveness, safety, timeliness, and affordability. Risk is examined both as a function of exposure to hazardous conditions or substances, in the traditional epidemiological approach, and as a function of economic incentives. Economic theory demonstrates the importance of effectively aligning economic incentives with intended consequences. Economic theory also points to the potential misalignment between the incentives of individual decision makers, such as employers, and the interests of society overall. For example, appropriately identifying, quantifying, and allocating costs to the specific activities that generate them, or “internalizing” costs, improves the alignment of employer incentives and the interests of society. Better understanding and quantification of the frequently hidden costs and consequences of occupational safety and health interventions is supported by a systems approach, accepted guidelines for the sound economic evaluation of interventions, and recent findings on the productivity impacts of worker injury and illness. An example is used to illustrate the effect that a specific intervention to protect agricultural workers from microbial exposures would have on employer economic incentives, and, through a systems approach, its consequences on worker safety and health, food safety, the environment, and society overall.

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