Controlling lead concentrations in human blood by regulating the use of lead in gasoline.

After having been emitted at maximum rates in the 1960s and 1970s, lead has become less ubiquitous in industrialized countries as a result of increasingly stringent policies to limit the use of this heavy metal as an anti-knock additive in gasoline. Using a detailed reconstruction of lead emissions in Europe (PbE), of the air concentration of lead in Europe (PbC) and repeated measurements of lead concentrations in human blood (PbB) in Germany since about 1980, we have constructed an empirical model that estimates PbB given PbE. This model is used for 2 purposes: i)To estimate PbB levels for the 1960s and 1970s in Germany, when emissions were maximum and monitoring blood levels had not yet begun. It turns out that PbB peak emissions were reaching a mean level, which health officials considered potentially harmful for fetuses and small children. ii) To estimate how PbB levels may have developed if regulations of the use of lead in gasoline had been implemented differently. In case of no or delayed regulations, the model estimates that PbB levels well beyond the critical level would have emerged. Thus, the regulation instituted in Germany since the 1970s has reduced significant health hazards.

Four decades of gasoline lead emissions and control policies in Europe: a retrospective assessment.

Over decades, large amounts of the neurotoxin lead were released into the European environment, mostly from gasoline lead additives. Emissions were growing unabatedly until the 1970s, when a series of regulations on the allowed gasoline lead content were adopted. As a result, in the 1990s most gasoline contained only small amounts of lead. We have examined this case of environmental pollution and regulation, and performed a retrospective assessment of the extent of regional-scale lead pollution and the effects of gasoline lead regulations in Europe. With the help of a regional climate model, NCEP re-analyses, spatially disaggregated lead emissions from road traffic and point sources, and various local data, the airborne pathways and depositions of gasoline lead in Europe since 1958 were reconstructed. It turns out that this approach is successful in describing the time-variable, spatially disaggregated deposition of gasoline lead. Additional data from analyses of concentrations in biota, including plant leaves, mussels and human blood, allows an assessment about the impact of the lead phase-out on the quality of the environment. Demonstrating the success of the lead policies, concentrations in leaves and human blood have steadily declined since the early 1980s. At the same time, the economic repercussions that had been feared did not emerge. Instead, the affected mineral oil and car manufacturing industries in Germany (our case-study) were able to deal with the effort without incurring significant extra costs. We suggest that our method of quantitatively reconstructing and anticipating fluxes and depositions of substances can be applied to other relevant substances as well, such as, for example, Persistent Organic Pollutants, radioactive substances or pollens.