Health risk of platinum group elements from automobile catalysts

Platinum group elements (PGE) are widely used in industries with an increasing number, and their emissions are resulting in elevated environmental concentrations of these rare metals. Automobile catalyst, which uses Pd, Pt, and Rh as active components, is the most important application field of PGE, and is becoming the main source of PGE emitted into the environments, contributing to a global increase in PGE concentrations. The paper reports the emitted PGE concentrations and distribution found in urban air and accumulated on the road surface and in roadside soil, plant, and their contamination of aquatic environments. The bioavailability, potential uptake into the biosphere, potential risks for humans and the environment are discussed.