Engine test stand experiments to assessing platinum uptake by plants

: Hertel, R.F.; Koch, W.; Kock, H.; König, H.P.; Rosner, G.; Windt, H.

Abstract
The loss of platinum from automobile catalytic converters is of increasing concern. However, the data base on both the qualitative and quantitative emissions as well as on the fate and effects of this noble metal in the environment is rather small. In the context of a government programme of the FRG, we have conducted engine test stand experiments with a three-way catalyst-equipped engine to determine platinum emissions and, as part of this project, to assess the potential platinum uptake by roadside vegetation. Grass cultures (Lolium multiflorum) were placed in continuously stirred tank reactors and exposed to slightly diluted (1:10/20) exhaust gas for 4 weeks (8 h/d, 5 d/week). With the atomic absorption spectrometry method used for the measurement of platinum emissions (on average 17 ng/mhigh3 or about 14 ng/km; derived from experiments with one catalyst), no platinum could be detected in the shoots at a detection limit of 2 ng/g.