Trace elements detection in whole food samples by neutron activation analysis, k0-method

Resumo

The increase in anthropogenic activities has been contributing to considerable increasing of the chemical elements concentration in the environment. One consequence is the need of monitoring the elemental composition of food available for consumption. Numerous techniques have been used to detect inorganic elements in biological and environmental matrices, always aiming reaching lower detection limits in order to evaluate the trace element content in the sample. This study evaluated the presence of inorganic elements in whole food samples, mainly elements on trace levels applying the neutron activation technique, k₀-method. This method produces accurate and precise results, without the need of chemical preparation of the samples. For this purpose, four samples of different types of whole foods were irradiated in the TRIGA MARK I IPR-R1 research reactor – located at CDTN/CNEN, in Belo Horizonte, MG, Brazil. It was possible to detect, in total, twenty-three elements. Nine elements are considered essentials, according to nutrition literature, thirteen are not essentials and one, classified as contaminant element by legislation. The majority of the elements determined are not reported in the TACO (Brazilian Table for Food Composition). It means that the professionals of health do not know, in fact, the real chemical elemental composition in foods and the population do not know what they are ingesting in terms of chemical elements and the risks of this ingestion. This study reaffirms the INAA, k₀–method, is an efficient technique for detecting trace elements in food samples.