PLATINUM DETERMINATION IN NUTRIENT PLANTS BY INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY WITH SPECIAL RESPECT TO THE HAFNIUM OXIDE INTERFERENCE

Platinum, emitted from automobile exhaust catalysts, is mainly oxidise d in a humic soil, as described previously [1]. An experiment with nut rient plants was carried out to elucidate the bioavailability and accu mulation of these platinum containing species. The plants [Allium cepa L. (Weiss, Fruhling), Rephanus sativus L. (Riesenbutter), Vicia faba L. (Hedin, Herzfreya), Zea mays L. (Delis) and Solanum tuberosum L. (S elma)] were grown under natural conditions. For mass balances all ways of platinum transport into and out of the system were monitored durin g the growing period. Plants growing in untreated soil took up less th an 1% of the platinum naturally present in the soil [0.15 +/- 0.11 mu g kg(-1) (78%)]. Plants growing in soil treated with a platinum contai ning tunnel dust took up slightly more platinum, The comparison of ICP -quadrupole-MS results with those obtained by a double focusing magnet ic sector ICP-MS showed a strong dependence of the platinum concentrat ion on the Hf-content in the sample. An evaluation method for the corr ection of the Hf-influence for ICP-quadrupole-MS is presented.