Assessment of human exposure risk related to contamination of Danish sow carcasses with bile containing Salmonella

In 2020, the Danish competent authority (CA) raised questions about the Salmonella exposure risk to consumers from bile-contaminated pig carcasses. This study assesses this risk related to sow carcasses. A total of 300 bile samples were collected aseptically at a large Danish sow abattoir. A selective method and medium, RAPID'Salmonella, was used to detect Salmonella and other family members. MALDI-TOF was used to identify bacterial species. None of the 300 bile samples were positive for Salmonella. A simulation model was set up to estimate the number of bile-contaminated carcasses with Salmonella that would go unnoticed on the market if the food business operator (FBO) had full responsibility for handling bile contamination. Data originated from our own and previous data collection, the Danish Meat Inspection Database and expert opinion from the CA and FBO. The FBO-scenario showed that a median of one (90% C.I. 0 - 7) carcasses carrying bile contamination with Salmonella would go unnoticed out of 281,000 in one year, whereas the CA-scenario showed a median of 14 (90% C.I. 1 - 63) such carcasses. Hence, the role of bile contamination on sow carcasses for the exposure of consumers to Salmonella seems to be negligible. Still, the FBO should be encouraged to prevent bile contamination.