Food Safety

Traditional approaches to achieving safe and wholesome food products have relied on process controls and enforcement of performance standards, but evaluation of the effects on public health of such measures was problematic at best. The recent use of quantitative microbial risk assessments, however, allows the evaluation of public health effects associated with consumption of contaminated foods, and the evaluation of the effect on public health of modifying the microbiological status of products in the food chain. Using our expertise in probabilistic risk assessments and food safety, we have been in the forefront of efforts to use quantitative microbial risk assessments in evaluation of food safety, and in the development of methodologies that connect the specification of microbiological limits on food contamination with public health outcomes. For example, we performed a quantitative microbial risk assessment for Clostridium perfringens in Ready-to-Eat and Partially Cooked foods for the U.S. Department of Agriculture (Golden et al., J. Food Protection 72(7):1376-1384, 2009; and the USDA Risk Assessment page for the complete documentation and model). We also led the way in demonstrating the practicality of internationally proposed approaches to estimating risk management metrics associated with microbial contamination of food (Crouch et al., J. Food Protection 72(1):2151-2161, 2009). The C. perfringens assessment included a state-of-the-art approach to dose-response evaluation; and we extended that approach to non-typhoid Salmonella species.[PDF] These examples illustrate some of the strengths that we bring to our consulting arrangements, including the use of advanced techniques where necessary, combined with the clear thinking needed to lay out logical and practical approaches.

We also assessed food safety on behalf of a plaintiff who had suffered severe food poisoning after ingesting chicken that had been infected with Salmonella blockley. We evaluated the conditions under which the microorganisms grew and multiplied in the grocery store where the chicken had been roasted and kept, and testified about our findings in court. The jury awarded the plaintiff $2,000,000.

Primarily in response to a report expressing surprise and alarm at finding measurable levels of lead in food, we examined concentrations of lead in foods. The data indicated that lead concentrations in foods in prior decades were much larger than recent measurements, and that lead concentrations in many foods continued to decline. We discussed the reasons for these trends, showed the trend in estimated total lead intake from foods, and note the similar trends seen in blood lead concentrations.[PDF]