Impact of motor vehicle exhausts on the cadmium and lead contents of clover plants grown around Egyptian traffic roads

Abstract

The lead and cadmium contents of clover plants and surface soil collected from different areas adjacent to roads having various traffic densities were investigated. Results indicated that lead and cadmium contents of clover plants are highly dependent on traffic density and distance from the road. Concentrations of about 40 μg/g lead and 1.6 μg/g cadmium were found in washed clover plant samples collected from areas adjacent to the Cairo‐Alexandria Road. Washing sometimes removed more than 50 percent of plant lead content. Dust precipitated on the clover plants grown at 2 m distances from the busiest investigated road were found to contain more than 2000 μg/g lead and 40 μg/g cadmium. These concentrations decreased with the distance from the road.