Isotopes as tracers of sources of lead and strontium in aerosols (TSP & PM2.5) in Beijing

David Widory (1) , Xiande Liu (2) , Shuping Dong (3)

1 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)
2 Chinese Research Academy of Environmental Sciences
3 National Research Center for Environmental Analysis and Measurements

Even after its being phased out in gasoline in the late 90s, lead (Pb) is still present at relatively high levels in the atmosphere of Beijing, China (0.10e0.18 mgm3). Its origin is subject to debate as several distinct sources maycontribute to the observed pollution levels. This study proposes to constrain the origin(s) of Pb and strontium (Sr) in aerosols, by coupling both Pb and Sr isotope systematics. The characterisation of the main pollution sources (road traffic, smelters, metal refining plants, coal combustion, cement factories, and soil erosion) shows that they can unambiguously be discriminated by the multi-isotope approach (206Pb/204Pb and 87Sr/86Sr). The study of total suspended particulates (TSP) and fine particles (PM2.5) from Beijing and its vicinity indicates that both size fractions are controlled by the same sources. Lead isotopes indicate that metal refining plants are the major source of atmospheric lead, followed by thermal power stations and other coal combustion processes. The role of this latter source is confirmed by the study of strontium isotopes. Occasionally, emissions from cement plants and/or input from soil alteration are isotopically detectable.

Mots clés: Air pollution; Lead isotopes; Strontium isotope; Aerosol sources

Domaines: Océan, Atmosphère; Sciences de l'environnement

David Widory, Xiande Liu, Shuping Dong. Isotopes as tracers of sources of lead and strontium in aerosols (TSP & PM2.5) in Beijing. Atmospheric environment, 2010, 44 (30), p. 3679-3687. ⟨10.1016/j.atmosenv.2010.06.036⟩. ⟨hal-00549066⟩