Effects of Changing to Unleaded Petrol on Traffic Related Emissions. Trace Metal and Lead Isotopic Evidence for Increased Pollution

In the late eighties, import of cars using high concentrations of alkyl-lead containing fuel was abandoned in the Netherlands. In addition the amount of alkyl-lead in petrol was significantly lowered. In 1997, lead was totally replaced by other additives in petrol. In order to see the effect this legislation the department of health (RIVM) started an investigation to the pollution of several forest soils located close to highways. The Dutch geological survey (now NITGTNO) was asked to determine the natural background of lead and trace metals and to investigate the several sources of lead by means of Pb isotopes.