M5 PM Marine Environmental Chemistry of Organic Pollutants
Monday, 14 November 2005: 1:50 PM - 5:30 PM in 321-323

(DAC-1117-822237) Oceanic biogeochemical sequestration of atmospheric persistent organic pollutants revisited.

Dachs, J.¹, Jurado, E.¹, Simó, R.², ¹ Department of Environmental Chemistry, IIQAB-CSIC, Barcelona, Catalunya, Spain² Institute of Marine sciences, CMIMA-CSIC, Barcelona, Catalunya, Spain

ABSTRACT- Sinking to the deep ocean and atmospheric degradation by OH attack are the two main permanent sinks of POPs such PCBs at the global scale. During the last decade several studies have focused in quantifying and understanding these two sinks. In the present work we have reviewed the oceanic and atmospheric sinks of PCB congeners using two complementary methodologies. The first involves the use of remote sensing data to quantify the spatial and temporal variability of environmental variables such aerosol load and size distribution, primary productivity, etc. This approach leads to an estimation of the global sink of PCBs of about 200 tn y-1. A second figure for global oceanic sink of POPs can be obtained by applying a recently developed global chemical tracer model for modeling the spatial and temporal distribution of pops. Both approaches will be compared and discussion will be presented on the role of water column cycling as a driver of atmospheric transport of POPs.

Key words: POPs, Oceanic sink, PCB, biogeochemistry