A quantitative risk assessment for Bacillus cereus emetic disease associated with the consumption of Chinese-style rice

A quantitative microbial risk assessment (QMRA) was undertaken to model the risk of the Bacillus cereus emetic foodborne disease syndrome associated w ith the consumption of contaminated Chinese-style boiled or fried rice. Usi ng Monte Carlo simulation, exposure variables were modeled for four differe nt food storage scenarios, including holding at room temperature (20C), und er optimal growth conditions (30C), under legal holding conditions (60C), a nd over a range of holding temperatures. Because human or animal feeding st udies are not available for the B. cereus emetic syndrome, epidemiological data was substituted for more conventional dose-response data. Exposure and dose-response assessments were combined, predicting a cumulative estimate for the risk of emetic illness associated with the consumption of B. cereus -contaminated Chinese-style rice of 2.13 x 10(-3), 5.50 x 10(2), 6.80 x 10( -2) and 6.11 x 10(-3) for the 60, 20 30C, and overall handling scenarios, r espectively. The QMRA revealed that the risk of illness was highly correlat ed with temperature abuse of cooked rice.