Isotopic source signatures for atmospheric lead:: The Northern Hemisphere

Aerosols collected between 1994 and 1999 at more than 80 different sites affecting the atmospheric composition of the Northern Hemisphere have been measured for their Pb-206/Pb-207, Pb-208/Pb-207 and Pb-206/Pb-204 ratios and Pb concentrations. The ratios are potentially useful for tracing sources of pollution and the movement of air-masses on a global scale. A change in isotopic composition compared to earlier measurements could be detected in the Western United States and parts of Europe, most probably due to long range transport of Pb pollution from China and Russia, respectively, and an increasing relative contribution of industrial Pb. The geographical variations found in the Pb isotopic composition of the aerosols made it possible to broadly characterize different regions via the Pb-206/Pb-207 (Pb-208/Pb-207) isotope ratios of the aerosols sampled: Eastern United States 1.173-1.231 (2.438-2.470); Western United States 1.159-1.188 (2.326-2.455); Canada 1.094-1.177 (1-.365-2.438); Mexico 1.188-1.197 (2.452-2.463); Japan 1.153-1.162 (2.435-2.443): China 1.141-1.177 (2.435-2.465): Germany 1.133-1.165 (2.405-2.440); Spain & France 1.097-1.142 (2.372-2.410); Northern Italy 1.148-1.160(2.419-2.430); Southern Italy 1.108-1.121(2.376-2.387); Eastern Europe and Russia 1.112-1.164 (2.388-2.446); North Africa & Arabian Peninsula 1.096-1.153 (2.361-2.431). Copyright (C) 2001 Elsevier Science Ltd.