Influence of culinary treatment on the concentration and on the bioavailability of cadmium, chromium, copper, and lead in seafood.

BACKGROUND: Seafood present important advantages for human nutrition, but it can also accumulate high levels of toxic and potentially toxic elements. Culinary treatments could influence seafood chemical element content and element bioavailability. In this study, the influence of culinary treatments on the total concentration and on the bioavailability of Cd, Cr, Cu and Pb in shark, shrimp, squid, oyster, and scallop was assessed. METHODS: Boiling, frying, and sautéing with or without seasonings (salt, lemon juice and garlic) were evaluated. Total concentration and bioavailability of Cd, Cr, Cu and Pb in seafood after all these culinary treatments were compared with those in uncooked samples. Analytes were determined by triple-quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). An alternative to express the results avoiding underestimated or overestimated values was proposed. RESULTS: The analytes concentration in seafood without culinary treatment varied from 0.0030 µg g-1 (shrimp) to 0.338 µg g-1 (oyster) for Cd; 0.010 µg g-1 (squid) to 0.036 µg g-1 (oyster) for Cr; 0.088 µg g-1 (scallop) to 8.63 µg g-1 (oyster) for Cu, and < 0.005 µg g-1 (shrimp, squid and oyster) to 0.020 µg g-1 (shark) for Pb. Only Cd (in scallop) was influenced by culinary treatments (reduction from 37 to 53 % after boiling, frying, and sautéing). Bioavailability percentage varied from 11% (oyster) for Cd; 18% (oyster) to 41% (shark) for Cr; 6% (shark) for Cu, and 8% (oyster) for Pb. Bioavailability percentage was not influenced by culinary treatments. CONCLUSION: Cadmium concentration was reduced in scallop after some culinary treatments (reduction o 37-53% after boiling, frying, and sautéing), but bioavailability percentage was not influenced. The employed analytical method was adequate for the purpose, presenting import results for food safety assessment about the influence of culinary treatments on metals concentration and bioavailability in seafood.