Interactive case studies: impact of feed material substitution on animal dietary exposure and risk characterisation

Ochratoxin A (OTA) contamination in animal feed poses potential risks to animal health and food safety. This presentation introduces the methodology for dietary exposure assessment and risk characterisation, followed by case studies illustrating the impact of feed contamination and ingredient substitution. The exposure assessment follows EFSA’s framework, using default values for animal body weights, feed intake, and OTA occurrence data. Risk characterisation is based on comparing exposure levels to the Reference Point (RP), with risks below 100% of the RP considered low. To explain the methodology, Case 1 focuses on a contaminated batch of feed, demonstrating the differences between the 95th percentile (P95 LB and UB) and mean exposure levels (mean LB and UB). This serves as the foundation for understanding how exposure is calculated and interpreted. Building on this, Case 2 and Case 3 explore the impact of ingredient substitutions. These cases assess how changes in feed formulation influence OTA exposure and risk characterisation, highlighting the importance of flexible risk assessment approaches.