Tools for Evaluating the Human Health Risks Associated with Microbial Contamination of Apples

Thesis (Master's)--University of Washington, 2015This thesis incorporates laboratory methods, risk assessment modeling, and policy analysis to address food safety issues related to microbial contamination of apple crops. Chapter 1 provides an introduction to microbial food safety issues and apple production in the United States. It also broadly discusses the conceptual underpinnings for the three subsequent chapters and specific aims of the thesis. More robust background information is provided within the respective chapters. Chapter 2 provides an analysis of a novel method for the quantification of E. coli on apple surfaces. Chapter 3 aims to evaluate the health risks of apple contamination under varying harvest and cleaning conditions, utilizing three quantitative microbial risk assessment models. The policy relevance of the study is discussed in Chapter 4, incorporating history of food safety policy, broad policy process frameworks, and a discussion of the relevant policy development stages in which the study findings may apply. As a whole, this thesis is intended to provide an interdisciplinary approach to issues surrounding apple production and consumption