Monitoring the trace metals concentration in rice by flame atomic absorption spectrometer and inductively coupled plasma atomic emission spectrometer.

ABSTRACT

The objective of this study was to monitor the concentration of trace metals in rice. Eight different commercial rice samples were collected from retail market and among these samples Fe, Cd, Cr and Zn metal concentrations were determined by using Flame Atomic Absorption Spectrometer (FAAS) and Inductively Coupled Plasma Atomic Emission Spectrophotometer (ICP-AES). The powdered rice samples were digested by wet chemical method. The analytical results obtained by both the instruments were found comparable. The accuracy of the method has been confirmed by analyzing Certified Reference Material CRM No. 10-b of National Institute for Environmental Studies (NIES). The concentrations of Fe, Cd, Cr and Zn in different brands were found in the range of 15.4 +/- 1.1 to 57.7 +/- 2.5 mg/kg, 0.08 +/- 0.03 to 0.39 +/- 0.05 mg/kg, 0.16 +/- 0.03 to 0.58 +/- 0.08 mg/kg and 7.3 +/- 0.3 to 18.6 +/- 0.5 mg/kg respectively. The standard deviation of the measurements has been calculated for Fe, Cd, Cr and Zn in six replicates of each sample and was found to be less than +/- 3% by the method proposed.