Determination of Low Levels of Cadmium in Foods Using a Chelating Ion Exchange Resin

Abstract A method is described for the determination of cadmium in foods which utilizes the AOAC HN03, H2S04, H202 digestion procedure catalyzed by V2O5. The cadmium is separated from the neutralized digest by a chelating ion exchange resin, eluted with H2S04, and determined by atomic absorption spectrophotometry. The average recovery of 0.30 ppm cadmium added to 7 commodities was 94% with a standard deviation of 2.8%, which compares favorably with the AOAC dithizone extraction method. The transfer, washing, and elution of 6 samples by the proposed method requires approximately 2 hr. The method allows the determination of as little as 10 ppb cadmium.