Ž . The Science of the Total Environment 236 1999 5774 Assessment of pollution aerosols sources above the Straits of Dover using lead isotope geochemistry Karine Deboudt a, , Pascal Flament a , Dominique Weis b , Jean-Paul Mennessier b , Patricia Maquinghen a a ( ) Uni ersite du Littoral-Cote d’Opale, LISE-ELICO UPRES-A CNRS 8013 , BP 59, F-62930 Wimereux, France ´ ˆ b Uni ersite Libre de Bruxelles, Departement Sciences de la Terre et de l’En ironnement, CP 160 02, B-1050 Brussels, ´ ´ Belgium Received 15 February 1999; accepted 8 June 1999 Abstract We assess the capability of lead isotopes to study the transport of pollution aerosols above the Straits of Dover by collecting atmospheric aerosols above the Eastern Channel and the Southern Bight of the North Sea. During the same period, we characterized the lead isotopic signature of the main industrial sources on the French coast near the Straits of Dover. Urban and automobile-derived aerosols were also collected. Due to the phasing out of lead in Ž 206 207 . gasoline, the urban isotopic composition Pb Pb 1.158 0.003 has become more radiogenic, although it is Ž highly variable. On a regional scale, major industrial emissions have a well-defined isotopic composition 1.13 206 207 . Ž 206 207 . Pb Pb 1.22 , more radiogenic than the petrol-lead signature 1.06 Pb Pb 1.12 . These results together with those measured near the main coastal highway show that the automobile source has become a minor component of particulate lead in air. On a local scale, Dunkerque, the most urbanized and industrialized area along the Straits of Dover, may transiently control elevated lead concentrations. Except for the occurrence of local and regional range transport episodes, lead concentrations in the Straits of Dover can be related to remote or semi-remote pollution source emissions. Combining air mass retrospective trajectories and related lead abundances and isotopic compositions, it can be shown that lead aerosols originating from eastern Europe have an isotopic Ž 206 207 . signature 1.145 Pb Pb 1.169 different from the isotopic composition of west-European lead aerosols Ž 206 207 . 1.111 Pb Pb 1.142 . The influence of remote North American sources is suggested, with caution, due to uncertainties in meteorological calculations. 1999 Elsevier Science B.V. All rights reserved. Keywords: Aerosols; Atmospheric transport; Lead isotopes; European lead sources Corresponding author. 0048-969799$ - see front matter 1999 Elsevier Science B.V. All rights reserved. Ž . PII: S 0 0 4 8 - 9 6 9 7 99 00286-7