National Institute of Nutrition, India
Sreenivasa RJ is an Asst. Director at National Institute of Nutrition, (ICMR), Hyderabad, India. He has completed his post graduation in Biochemistry and doctoral studies from Osmania University, Hyderabad. He has published several research papers in reputed peer reviewed journals and presented his research contributions in several National and International conferences and workshops. He holds life membership in professional scientific organization. He has been an invited distinguished speaker for many universities for discourse on heavy and trace metal toxicity, food composition and nutritional health. Presently he is working on, plant secondary metabolites and heavy metals in Indian foods using ICPMS. His core area of research also includes evaluation of carotenoid metabolism. He is a board member of NIN Scientist Association and Security and maintenance committee.
Heavy metals are natural components of the earth's crust and are widely used in agricultural, manufacturing and food/material processing industries. Among a variety of substances entering the soil, inland waters and the ocean as waste products, heavy metals like Nickel, Arsenic, Cadmium, Mercury and Lead are prominent. Heavy metal toxicity is a result of long term, low level exposure to pollutants through air, water and numerous consumer food products. In the field of food and nutrition the increasing levels of heavy metals in the environment, their entry into the food chain, and the overall health effects on people who consume green leafy vegetables (GLV) and fish are of major concern to researchers. In the present study the heavy metal content was analyzed from GLV and fish samples. Closed vessel microwave digestion system (CEM-MARS-USA).of food samples assisted by HNO3+ H2O2 were used to determine the heavy metals using ICPMS. CRM samples procured from NIST were used for method standardization and validation for linearity, repeatability, limits of detection (LOD) and limits of quantification (LOQ). Heavy metal measurements were performed using ICP-MS (PerkinElmer Élan 9000-USA). For better operating conditions the ICP-MS was adjusted to Nebulizer gas flow 0.91 L/min, Radio frequency (RF) 1200 W, Lens voltage 1.6 V, Cool gas 13.0 L/min, and Auxiliary gas 0.70 L/min. Microwave digestion followed by analysis by ICP-MS has been shown to be a simple, reliable method for the multi-element determination of heavy and trace metals in GLV and Fish samples. Results were in accordance with recommended human daily intake values except for arsenic, which were in agreement with WHO/FAO recommended values. Several reliable analytical methods like Colorimetric and Atomic Absorption Spectrophotometer are available for monitoring heavy metals in food samples, but ICP-MS is the most sophisticated and reliable technique, fast quantitative, high sensitivity, good precision and accuracy. Isotope ratio measurements were also possible using ICP-MS and interferences relatively few in number compared to other analytical techniques.