Validating the analytical methodologies for determining some important trace elements in food consumed in India

This paper reports on the development, standardization, and application of instrumental as well as radiochemical neutron activation analysis (INAA and RNAA) techniques for determining the concentrations of iron, zinc, cobalt, cesium, strontium, selenium, thorium, and calcium in food consumed in India. Based on the analysis of 20 diet samples, prepared as per the data on dietary intake patterns of an adult in four provinces of India and that of an average adult Indian, the geometric mean (GM) intake of various elements for the reference Indian man was estimated to be 15.9 (10.7-34.4) mg for iron, 8.6 (5.1-15.6) mg for zinc, 17.0 (8.3-31.4) micrograms for cobalt, 4.76 (2.8-11.8) micrograms for cesium, 1.46 (0.79-2.96) mg for strontium, 52.4 (35.0-130.8) micrograms for selenium, 0.75 (0.44-1.75) micrograms for thorium, and 0.35 (0.17-0.67) mg for calcium. A comparison of the daily dietary intakes of these trace elements by the reference Indian man was made with that of the International Commission on Radiological Protection (ICRP) reference man and also with the world average compiled by the International Atomic Energy Agency (IAEA). When compared with the ICRP reference man data, the daily dietary intakes of all the eight elements by the reference Indian man were considerably lower by factors ranging from 1.4 for strontium to as much as 18.0 for cobalt. However, when compared with the world average, daily dietary intakes by the reference Indian man were comparable for iron and lower by factors 1.2 to 1.9 for zinc, selenium, and calcium.