Bioaccumulation of palladium, platinum and rhodium from urban particulatesand sediments by the freshwater isopod Asellus aquaticus

The three-way catalytic converters introduced to oxidize and reduce gaseous automobile emissions represent a source of platinum group elements (PGEs), in particular platinum, palladium and rhodium, to the urban environment. A brasion of automobile exhausts leads to an increase of the concentration of PGEs in environmental matrices such as vegetation. soil and water bodies. The bioaccumulation of Pd, Pt and Rh by the freshwater isopod Asellus aquat icus was studied in natural ecosystems and under laboratory conditions. Owi ng to the low concentration level (ng g(-1)) of PGEs in the animals studied , analyses were performed with a quadrupole inductively coupled plasma mass spectrometry (ICP-MS) and hafnium, copper, yttrium, rubidium, strontium an d lead were monitored for spectral interference correction. Asellus aquatic us collected in an urban river showed a content (mean +/- s) of 155.4 +/- 7 3.4, 38.0 +/- 34.6, and 17.9 +/- 12.2 ng g(-1) (dry weight) for Pd, Pt and Rh, respectively. The exposure of Asellus aquaticus to PGE standard solutio ns for a period of 24 h give bioaccumulation factors of Bf: 150, 85, and 7 for Pd, Pt and Rh, respectively. Exposure of Asellus aquaticus to environme ntal samples for different exposure periods demonstrated that PGE bioaccumu lation is time dependent, and shows a higher accumulation for the materials with a higher PGE content. While all three elements have the same uptake r ate for exposure to catalyst materials, for exposure to environmental mater ials they have a different uptake rate which can be attributed to transform ations of the PGE species in the environment. (C) 2001 Elsevier Science Ltd . All rights reserved.