Neutron activation analysis characterization procedures for fish consumed at São Paulo City

Abstract

The characterization of edible tissues of fishes consumed by humans is very important for determination of several toxic and potentially toxic elements, ensuring the food safety. The Instrumental Neutron Activation Analysis (INAA) comparative method allows the determination of several of these elements, as well as others, for example of nutritional character. This study is part of the International Atomic Energy Agency (IAEA) technical cooperation project of Latin America and Caribbean countries to ensure the quality of food and biomonitoring of contaminants in molluscs and fishes. Ten specimens of 5 of the most consumed fish in São Paulo city: whitemouth croaker (Micropogonias Furnieri), smooth weakfish (Cynoscion learchus), common snook (Centropomus undecimalis), Brazilian sardine (Sardinella brasiliensis) and bluefish (Pomatomus Saltatrix) were analyzed. Complete procedures for analysis, which includes purchase in the largest warehouse in Latin America, transport to the laboratory, storage, freeze-drying, milling, weighting and others preparations of the subsamples, and the short irradiation parameters for the determination of Br, Cl, K, Mn and Na are reported. Results obtained for macro and microelements are presented and are in agreement with analysis of oyster tissue and mussel tissue certified reference materials under the same irradiation conditions, with z-score values ranging from -3.0 to 2.2.