Monitoring of lead levels in the environment associated with motor vehicle emissions.

Despite the considerable studies done on the lead pollution problem, and the agreement about the damaging effects of lead on public health, the potential hazard of lead from vehicles has not yet been covered completely. The investigation of the relationship between lead levels and traffic density in different areas (rural and urban) could contribute significantly to our understanding of lead pollution. In the present work the lead concentrations in the atmosphere, soil, and vegetation were followed before and after opening a major road (A3 by-pass) in the Guildford area. Most of the sampling locations were situated close to the A3. Matrix effects were investigated by the addition of excess amounts of various cations and anions to standard lead solution. During the course of sampling air particulates, it was noticed that position of the exhaust system depended on the make of vehicle (the majority of vehicles have the exhaust outlet pointing away from the driver's side). The exhaust position may not be important in the sampling of lead near motorways or open roads, but it could be important in towns, particularly in one-way systems; therefore, initial experiments to investigate the effect of exhaust position on lead levels were carried out. Attempts were also made to measure carbon monoxide concentrations in the atmosphere. Overall lead levels in the atmosphere increased significantly from 0.4mug m-3 to 1.5mug m-3, during the sampling period 20 months, while soils changed from 52mug/g to 67 mug/g. However, the lead content of grass 50 m from the road showed a substantial increase from 11 mug/g (dry matter) to 27 mug/g