The Use of Multi-Criteria Decision Analysis in Performing Alternatives Assessment and Comparative Risk Analysis: The Case Study of Codling Moth Pesticides

Thesis (Ph.D.)--University of Washington, 2016-08Risk assessment increasingly involves a more systemic evaluation of alternatives and their feasibility, risk, and benefit, in the form of alternatives assessment. However, quantitative, flexible, and standardized methods are still lacking for such analyses. A multi-criteria decision analysis method is proposed here as a framework for comparative risk assessment and alternatives assessment, whereby the feasibility and adoption of alternatives can be assessed and predicted while at the same time evaluating health-health tradeoffs among alternatives. An illustrative case study of occupational exposures to ten different codling moth pesticides is presented. Agricultural consultants to the tree fruit industry were surveyed and interviewed to examine pesticide preferences and the weight of selection criteria. Health impact valuations were also carried out, as the population of participants is uniquely qualified as well-informed about pesticides and having occupational experience with their application, and with pesticide selection. Decision models were constructed based on these results to attempt to predict pesticide use before and after the paradigm shift resulting from the cancellation of one alternative, azinphos-methyl. Monte Carlo simulation was used to assess probabilistic estimates of doses to handlers of the ten pesticides with a variety of associated potential health outcomes. Toxicological data from the pesticide registration process was used to construct benchmark doses for comparison with human dose estimation, producing a probability of exceeding this limit of acceptable dosing. The fraction exceeding the benchmark was used in a decision analysis model revealing health-health tradeoffs among the alternatives