Researchers report that lead from historical gasoline use continues to affect air quality in urban London almost 20 years after its final phase-out as an additive. From the late 1980s onward, atmospheric concentrations of lead, a toxic environmental pollutant, in Europe and North America fell as its addition to gasoline was reduced. However, Eléonore Resongles, Dominik Weiss, and colleagues report that lead from historical gasoline use continues to affect air quality in London almost 20 years after its final phase-out as an additive. The authors examined whether remobilization of lead dust deposited from historical gasoline use contributes to airborne lead particles in a contemporary urban environment. To do so, the authors analyzed the lead isotopic ratios of airborne particles collected at a busy street-level location and at building height in London between 2014 and 2018. Comparing the ratios with historical data, the authors found that, after a shift between 1998 and 2001, the isotope ratios remained unchanged over the last decade, suggesting that its sources have not changed. The isotopic ratios match that of road dust and topsoil and do not vary seasonally, indicating that the airborne lead is attributable to resuspension of dust rather than to current coal burning. The authors also modeled historical contributions of leaded gasoline to overall atmospheric lead. According to the authors, gasoline-derived lead remains an important source of lead in the environment and should be considered in abatement measures.
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Article #21-02791: "Strong evidence for the continued contribution of lead deposited during the 20th century to the atmospheric environment in London of today," by Eléonore Resongles et al.
MEDIA CONTACTS: Eléonore Resongles, HydroSciences Montpellier, Montpellier, FRANCE; tel: +33 678 338 704; email: < eleonore.resongles@ird.fr >; Dominik Weiss, Imperial College London, UNITED KINGDOM; email: < d.weiss@imperial.ac.uk >
Proceedings of the National Academy of Sciences