Influence of various cooking processes on the concentrations of PCDD/PCDFs, PCBs and PCDEs in foods

The effects of several cooking processes commonly used by the population of Catalonia (Spain) on the total concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFs), polychlorinated biphenyls (PCBs), and polychlorinated diphenyl ethers (PCDEs) were assessed in various foodstuffs. The levels in raw and cooked samples were determined by HRGC/HRMS. Cooking processes (fried, grilled, roasted, and boiled) had different effects on the levels of PCDD/PCDFs in fish, while in meats cooking reduced PCDD/PCDF concentrations in veal and pork. In the remaining foodstuffs, the differences were only relevant for fried potatoes. Cooking showed also different effects on the levels of PCBs in fish, while in meats cooking enhanced PCB concentrations. Cooking processes enhanced ΣPCDE levels in most fish and meat samples. These results show that, in general terms, cooking processes are only of limited value as a means of reducing concentrations of PCDD/PCDFs, PCBs and PCDEs in food.