Platinum and rhodium in wine samples by using voltammetric techniques Diana Amorello a , Salvatore Barreca b,c , Elisa Gulli a , Santino Orecchio a, ⁎ a Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche, Università di Palermo, Viale delle Scienze, I-90128 Palermo, Italy b ARPA, Milano, Italy c Istituto Euro Mediterraneo di Scienza e Tecnologia (IEMEST), Via Michele Miraglia, 20, 90139, Palermo, Italy abstract article info Article history: Received 24 June 2016 Received in revised form 19 September 2016 Accepted 20 September 2016 Available online 21 September 2016 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 particu- lar, differential Pulse Voltammetry (DPV/a) and Adsorptive Stripping Voltammetry (AdSV) were used for the de- termination 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 μgL -1 and from 0.0006 to 0.36 μgL -1 respectively. 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. © 2016 Elsevier B.V. All rights reserved. Keywords: Pt Rh Wine Voltammetry 1. Introduction Over the last decades, the increasing industrial demand of platinum and rhodium, together with other elements (palladium, ruthenium, iridium, osmium, etc.), has caused their anthropogenic emissions and spread in all the environmental matrices [1–5]. In particular, in many countries, legislation was introduced in order to establish limits for the emission of few undesirable compounds (CO, NO x , SO 2 , Pb, etc.) emitted by vehicles; moreover, in order to comply the limits of emis- sions, catalytic converter technology has proven to be the most active control system. The decrease of these pollutants are catalyzed by oxides of transition metals, noble metals and Platinum Group Elements (PGE) (Pt, Os, Ir, Ru, Rh and Pd). Nowadays, vehicles catalysts contain different combinations of PGE in order to achieve optimum performance charac- teristics and to further reduce the emissions of contaminants [2,6,7]. By considering that these metals, as other contaminants, may be also dis- persed in silt, soil, water and accumulated in plants [8,9,10], a rapid ac- cumulation in the environment were observed: in German soils, between 1999 and 2005, an increase of PGE concentrations, nearly alongside heavy traffic roads was observed [4]. Analogous to these find- ings, especially Pt and Rh concentrations were found to be elevated in airborne dust [3,11,12]. These data made concern arise about potential environmental and health risks [13,14]. Although these metals are usually emitted by vehicles as oxides [15– 18], it is known that, in the environment, they can be transformed [19] into soluble compounds by complexation with natural ligands which can enter the food chain [20–23]. In the previous years, PGE automobile emitted were well-known to be relatively inert, but several recent stud- ies demonstrated the biological availability of soluble as well as particle bound PGE to organisms [24–25]. Several studies have been undertaken to determine the effects of Pt emissions on humans and to the environ- ment [26–31]. No evaluations of Pt and Rh concentrations have ever been carried out in common food since the use of PGE in catalytic converters, and no data are available on the these two metal concentrations in wines. This paper is the first analytical approach to quantify the two heavy metals in alcoholic beverages. In this study a total of 40 different wine samples produced in Italy and Malta, a vodka and a brandy were inves- tigated. This requires the development of reliable analytical methods to measure very low Pt and Rh concentrations in food and environmental matrices, as well to estimate background concentrations of both. In par- ticular, the main intention of this work was to develop a reliable method for the quantification of Pt and Rh in complexes matrices, as wine, be- cause they cannot be readily measured using conventional techniques employed in most laboratories, in particular, the ICP techniques due to matrix and spectra interferences. Moreover, a direct determination of Microchemical Journal 130 (2017) 229–235 ⁎ Corresponding author. E-mail address: santino.orecchio@unipa.it (S. Orecchio). http://dx.doi.org/10.1016/j.microc.2016.09.010 0026-265X/© 2016 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Microchemical Journal journal homepage: www.elsevier.com/locate/microc