Platinum and Palladium transfer to milk, organs and tissues after a single oral administration to lactating goats

Platinum (Pt) and Palladium (Pd) are massively used in catalytic converters, emitted with exhaust fumes and deposited on roadsides in particle sizes. If they are ingested by ruminants grazing in agricultural fields located along roads they may enter the food chain. The objective of this study is to assess the potential transfer of Pt (PtCl(2)) and Pd (PdCl(2)) towards milk, tissues (muscle) and organs (kidney, liver and mammary gland). Three lactating goats received orally a single dose of 200mg of Pd and 200mg of Pt at the beginning of the experiment. The milk was collected each day during eight days. On the eighth day, organs and tissues were sampled to analyse the metal concentrations by ICP-MS (quantification limit of 0.25ng/g for Pd and Pt, detection limit of 0.08ng/g). The experiment demonstrated a significant transfer of Pd and Pt to kidney. The detected concentration was, respectively, of 73.9ng/g DW and 268.5n/g DW (factor 22 and factor 73 compared to the control kidney). The amounts of metals were : in the liver,18.1ng/g DW for the Pd and 8.1ng/g DW for the Pt, in the mammary gland, 14.9ng/g DW fort the Pd and 2.5ng/g DW for the Pt and in the muscle, 4.9ng/g DW for the Pd and 0.6ng/g DW for the Pt. The Pd concentration detected in milk was higher (from 5ng/g DW to 9ng/g DW) than in control milk but the transfer factor remained very low (0.02%). The Pt in milk could not be detected because it was below the quantification limit (<0.25ng/g DW).