A plenty of studies assess the increase in metals around in environment. Many places and many metals are concerned all over the world. here we'll focuse mainly on Platinum and Palladium
As platinum and palladium are used as catalic converters the main source of pollution is close the axis of car traffic, i.e. roads and highways. Several studies show differents concentrations as context of measures are always differents and the factors involved in concentration are much complex.
The average concentration of platinum and palladium can reach values of 22.74µg/kg for platinum and 120.8µg/kg just near the road. As we can forsee, the concentration is dependent of the distance of the road and indeed values fall to 2.04µg/kg and 84.2µg/kg for platinum and palladium respectiveley is measure are carried out 5 meters aways from the road [1]
Plants thriving near the roads accumulate metals as expected as their concentrations for platinum and palladium respectiveley are in average about 8.64µg/kg and 10µg/kg respectiveley[2].
Near roads in Germany, with a heavy traffic of about 16,000 car a days and with a speed limit of 80km/h, platinum concentrations have been estmiated around 50µg/kg. Concentrations in soils town center have even shown a value of 90µg/kg!Cite error: Closing </ref> missing for <ref> tag
Coal
170µg/kg