The increase of deposition of air pollutants such as platinum group elements (PGEs) Pt, Pd and Rh, and polycyclic aromatic hydrocarbons (PAHs) from vehicles on plants is raising serious concerns about the risk for the quality of food and, in turn, for human health. PGEs have recently emerged in ecosystems due to their massive use as catalysts in the automobile industry. PAHs are combustion by-products known for their carcinogenic properties. This investigation reports the first pollution maps of PGEs and PAHs at the agricultural scale (Figure).

Figure: Pd pollution map at the agricultural scale. Pd levels were measured by setting greenhouse-grown ryegrass pots at regular spacing (black dots) in an experimental field in Lorraine, France. The increase of Pd levels near the road evidences the grass contamination by Pd from vehicles. The article shows also pollution maps for Pt, Rh and polycyclic aromatics hydrocarbons (PAHs).