APMP supplementary comparison APMP.QM-S3: Cd in rice

Abstract

The supplementary comparison APMP.QM-S3 has been carried out in parallel with APMP.QM-P12 to demonstrate and document the capability of NMIs in the APMP region for determination of Cd content of sub mg/kg level in rice and related food matrix materials. As an activity of the Technical Committee for Amount of Substance (TCQM) of the Asia Pacific Metrology Programme (APMP), it was coordinated by KRISS (Korea Research Institute of Standards and Science, Korea) with NIM (National Institute of Metrology, China) and NMIJ (National Metrology Institute of Japan, Japan) as co-coordination laboratories to provide a reference value. Seven national metrology institutes (NMIs) in the APMP participated in the supplementary comparison.Four participants used double isotope dilution mass spectrometry (ID-ICP/MS) for determination of Cd in rice, while the other two participants used graphite furnace-atomic absorption spectroscopy (GF-AAS) with either external calibration or standard addition. The degree of equivalence for results obtained with double ID-ICP/MS was satisfactory with less than 5% deviation from the reference value even in the worst case. Results from GF-AAS, however, exhibited significant discrepancies from the reference value, which indicate that the method employed requires improvements including rigorous control of parameters and method validation. The majority of the participating laboratories directly demonstrated their capability to measure cadmium in rice and will be able to apply such expertise to a range of samples and analytes with similar matrices.Main text.To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by APMP, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).