RAPID AND SENSITIVE DETERMINATION OF IODINE IN FRESH MILK AND MILK POWDER BY INDUCTIVELY COUPLED PLASMA - MASS-SPECTROMETRY (ICP-MS)

A rapid and sensitive method for the determination of iodine in fresh milk and milk powders by inductively coupled plasma - mass spectrometry is described. The method is applied to the analysis of the two standard reference materials BCS-CRM Nos. 63 and 150. The iodine concentrations found in these materials are 0.28±0.01 μg/g and 1.21±0.01 μg/g, respectively. In fresh milk, iodine concentrations between 50 and 2300 ng/ml were determined. The ICP-MS results for these milk samples are compared to the results which were obtained by a chemical method and by X-ray fluorescence analysis. Because of the simple sample preparation and the good sensitivity and selectivity ICP-MS is the only method which allows the determination of iodine in milk samples down to the lower ng/ml range together with a high sample throughput. © 1990 Springer-Verlag.