Trace elements in diets determined by nuclear techniques and their sources

摘要

Food and beverages ingested by humans represent a potentially proficient pathway of exposure to toxic and nutritionally important minor and trace elements. At the present time, less than one third of the 90 naturally occurring elements are known to be essential for life. If 11 major elements and 6 noble gases are excluded, 73 elements of the periodic system remain and, because of their low concentration in living matter, are termed 'trace elements'. Also, it may not be correct to classify them as essential and toxic elements because toxicity, while inheent in au elemens, is buta function of the concentrations to which humans are exposed. Therefore, a logical classification of the 73 trace elements would be those with proven essentiality and the rest for which essentiality is 'not now known', This classification leaves room for the possibility that future research will include additional elements as being essential.