Rare earth elements and (87)Sr/(86)Sr isotopic characterization of Indian Basmati rice as potential tool for its geographical authenticity.

The increasing demand for premium priced Indian Basmati rice (Oryza sativa) in world commodity market causing fraudulent activities like adulteration, mislabelling. In order to develop authentication method for Indian Basmati rice, (87)Sr/(86)Sr ratios and REEs composition of Basmati rice, soil and water samples were determined and evaluated their ability as geographical tracer in the present study. In addition, the possible source of Sr in rice plant has also been examined. Basmati rice samples (n=82) showed (87)Sr/(86)Sr ratios in the range 0.71143-0.73448 and concentrations of 10 REEs (La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Er, Yb) in ppb levels. Statistical analysis showed strong correlation between (87)Sr/(86)Sr ratios of rice, silicate and carbonate fractions of soil. Good correlation and closeness of (87)Sr/(86)Sr of rice with water indicate its uptake in rice from water. Rice grown in southern Uttar Pradesh contains higher (87)Sr/(86)Sr compared to other region of Indo-Gangetic Plain due to higher (87)Sr/(86)Sr of the Ganga compared to other rivers. (87)Sr/(86)Sr ratios can be used as a tracer for differentiating Indian Basmati rice from the other country originated rice samples.