Platinum concentrations in urban road dust and soil, and in blood and urine in the United Kingdom†

Abstract

Increasing Pt concentrations from vehicle catalysts have been reported from a number of countries. Analysis of Pt and Pd in soils and road dusts taken from areas of high and low traffic flows in SE England show concentrations of Pt in the range < 0.30-40.1 ng g-1 and Pd in the range < 2.1-57.9 ng g-1. Higher concentrations of Pt are associated with high traffic densities. Samples taken from streets of lower traffic flows were found to contain the lower concentrations of the ranges. Pilot studies of Pt concentrations in blood and urine using ICP-MS have been carried out. Platinum concentrations in whole blood were: precious metal workers, 780-2170, mean 1263 pmol l-1 (0.152-0.423, mean 0.246 microgram l-1); motorway maintenance workers, 645-810, mean 744 pmol l-1 (0.126-0.158, mean 0.145 microgram l-1); Imperial College staff, 590-713, mean 660 pmol l-1 (0.115-0.139, mean 0.129 microgram l-1). Platinum concentrations in urine in pmol Pt per mmol creatinine were: precious metal workers, 122-682, mean 273 [0.21-1.18, mean 0.47 microgram Pt (g creatinine)-1]; motorway maintenance workers, 13-78, mean 33.7 [0.022-0.135, mean 0.058 microgram Pt (g creatinine)-1]; Imperial College staff, 28-130, mean 65.6 [0.048-0.224, mean 0.113 microgram Pt (g creatinine)-1]. Detection limits were 0.03 microgram l-1 for both blood and urine. The possible health effects of increasing Pt in the environment are discussed. Platinum provides an excellent example of the significance of speciation in metal toxicity. Platinum allergy is confined to a small group of charged compounds that contain reactive ligand systems, the most effective of which are chloride ligand systems. Metallic Pt is considered to be biologically inert and non allergenic and since the emitted Pt is probably in the metallic or oxide form, the sensitising potential is probably very low. Platinum from road dusts, however, can be solubilised, and enter waters, sediments, soils and the food chain. There is at present no evidence for any adverse health effects from Pt in the general environment, particularly allergic reactions.

Influences on human internal exposure to environmental platinum

“…Emission of soluble and therefore possibly toxic platinum is estimated to be about 1% (Artelt et al, 1999 ). Occupationally related uptake of platinum by inhalation from car traffic seems to be of no relevance as far as internal exposure is concerned (Begerow et al, 1999a;Farago et al, 1998 ).…”

“…Depending on the analytical method applied and the study group, different levels of platinum in urine have been reported (Table 1 ) (Weber et al, 1991;Ensslin et al, 1994;Schierl et al, 1994Schierl et al, , 1998Schramel et al, 1995;Begerow et al, 1996Begerow et al, , 1997Begerow et al, , 1999aFarago et al, 1998;Philippeit and Angerer, 1999;Schierl, 2001 ). To date, it is not known to what extent different exposure pathways and the chemical species influence the platinum concentration in environmentally exposed humans.…”

“…It has been shown to be related to the workplace, for example, dental and precious metal work. Studies concerning road workers have not shown a higher internal platinum exposure due to these workplaces (Farago et al, 1998 ). Noble metal dental alloy restorations ( NMDAR ) are known to vary and to contain up to 20% platinum depending on the type of restoration and the composition of the alloy ( Bundeszahnaerztekammer and Kassenzahnaerztliche Bundesvereinigung, 1998 ) and therefore influence the internal platinum exposure ( Table 2 ) probably after oral uptake of metal platinum (Philippeit and Angerer, 1999;Schierl, 2001 ).…”

“…Regarding toxicology and sensitization, platinum emitted in metallic or oxide form is considered to be biologically inert and non -allergenic ( Farago et al, 1998 ). Although platinum from road dusts can be solubilized and enter water, sediment, soil and the food chain, there is at present no evidence for an adverse health effect, particularly allergenic, from platinum in the general environment (Farago et al, 1998 ).…”

“…Although platinum from road dusts can be solubilized and enter water, sediment, soil and the food chain, there is at present no evidence for an adverse health effect, particularly allergenic, from platinum in the general environment (Farago et al, 1998 ). Adverse health effects such as dermatitis and asthma are related to occupational exposure to platinum salts and nephrotoxicity and carcinogenicity to cancer medication with cisplatin (IARC, 1987;Merget et al, 1999;Newman Taylor et al, 1999;Sato et al, 2000 ).…”