Mineral oil and PCB/dioxin analysis in some European food contamination episodes

Following a contamination of the animal food chain in Belgium with PCBs, we investigated if there was a link between the presence of PCBs and the mineral oil content. The concentrations of mineral oil hydrocarbons in samples highly contaminated with PCBs were identical with those observed in samples with very low concentrations of PCB collected from non-contaminated farms or supermarkets. We concluded that the introduction of PCBs in the animal food chain was done by the use of pure transformer oil and not by waste oils (used edible, hydraulic or motor oils) collected at the recycling centres. The concentrations of mineral oil were lower than samples collected and analysed in Switzerland during the summer of 1999 when relatively high levels were measured.