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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]
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>
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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]. Somes species of birch trees are also able to accumulate platinum to a value up to 1350ng/g and ashes from pine trees presents platinum concentration around 5000ng/g[3].
Even greater value have been found, reaching the impressive value of 132µg/kg[4].
Concentrations found in Rhine river help to realize how concentrations in platinum could increase with the effluents due to the rain washing. Concentration usually found are about 5ng/g but after a rain events (all soils, and surfaces are washed out) this concentration reach a value of 31.2µg/g thus increased a thousand times [5]
Coal 170µg/kg