J. Phys. IV France
Volume 107, May 2003
Page(s) 369 - 372

J. Phys. IV France
107 (2003) 369
DOI: 10.1051/jp4:20030318

Pollutant lead transport and input to the Caribbean during the 20 $\mathsf{^{th}}$ century

F. Desenfant1, G.F. Camoin1 and A. Véron1, 2

1  UMR 6635 du CNRS, Centre Européen de Recherche et d'Enseignement en Géoscience de l'Environnement (CEREGE), Université d'Aix-Marseille III, Europôle de l'Arbois, 13545 Aix-en-Provence, France
2  GEOTOP-UQAM, Succursale Centre Ville, Case Postale 8888, Montréal, Québec H3C 3P8, Canada


Here we evidence significant shifts in the sources of Pb input to the Caribbean based on lead isotope records from massive corals collected near Puerto Rico. While mean Pb/Ca ratios in these corals generally mimic alkyl Pb consumption in the US, we observe a 5 to 8 years delay in the maximum Pb peak in the 1970s. Pollutant Pb decay in corals is not as rapid as expected from the phasing out of leaded gasoline related to European and regional sources. Furthermore, 206Pb/ 207Pb imprints often display significant interannual variations with no clear temporal evolution. This seems to be partly connected to specific meteorological events and seasonal atmospheric shifts with mixed input from the southern US, Europe and Latin America/Caribbean. New corats from the Western Caribbean (Martinique, Guadeloupe) are presently analysed in order to investigate these isotopic shifts in relation to atmospheric input sources and oceanic recirculation.

© EDP Sciences 2003