Probabilistic intake assessment and body burden estimation of dioxin-like substances in background conditions and during a short food contamination episode

The objective was to perform a dioxin body burden estimate based on a probabilistic intake assessment of PCDDs, PCDFs and dioxin-like PCBs because of the so-called 1999 ‘Belgian dioxin incident’. Monte Carlo simulation techniques were used to combine detailed 7-day food intake data on the individual level from a sample of 14–18-year-old adolescents with ‘background’ and ‘incident-related’ food contamination data. In background conditions, 3% of the adolescents had an intake <1 pg TEQ kg-1 bw day-1, while 85% had <4 pg TEQ kg-1 bw day-1. Milk and other dairy products were the basic source of dioxin-like contaminants, while fish constituted the main source at the higher percentiles of intake. During the dioxin incident, the estimated median dioxin intake showed a moderate increase. At the 99th percentile, the highest intake level, and the 95% upper bound uncertainty level, peak body burden—23.73 ng TEQ kg-1 bw—remained below body burdens that in the experimental animal or in man are accompanied by a population-based observable increase in the incidence of adverse effects. The 1999 Belgian dioxin incident most likely did not affect public health in Belgium in a measurable way, although exceptions remain possible on the individual level.