Platinum and rhodium in wine samples by using voltammetric techniques

Abstract

For the first time, the concentrations of Pt and Rh in 42 different alcoholic beverages (white and red wines, vodka and brandy) produced in Italy, Malta and Gozo were investigated. Only the voltammetric techniques, in particular, differential Pulse Voltammetry (DPV/a) and Adsorptive Stripping Voltammetry (AdSV) were used for the determination of Pt and Rh respectively. Accuracy was tested with standard addition method and recoveries ranged from 90% to 98%. In analyzed wine samples, Pt and Rh concentrations are in the ranges from 3 to 470 μg L− 1and from 0.0006 to 0.36 μg L− 1respectively. We found a Pt/Rh ratios ranged from 37 to 180,000, in quite disagreement with the ratio in catalytic converters. Unlike other investigated matrices (settled dust matter), the concentrations of Pt and Rh are not correlated, suggesting that the grape or the plant (vitis vinifera) treats the two metals very differently. Daily intakes (DIM) of Pt and Rh were calculated. Consuming 200 mL/day of wine, this supply from 0.6 to 94 μg and from 0.00012 to 0.072 μg of platinum and rhodium for person respectively.