Transport of persistent organic pollutants by organo-mineral aggregates (OMAs) in the Lisboa–Setúbal Canyon system

Abstract

In this work we investigate the role of organo-mineral aggregates (OMAs) in the transport and deposition of persistent organic pollutants in the Lisboa–Setúbal Canyon system. OMAs are more easily remobilized than the underlying sediment surface, and are easily transported in the benthic boundary layer. Since aquatic sediments act as sinks for hydrophobic organic contaminants, OMAs must be a factor in the lateral transport of organic contaminants. Submarine canyons further facilitate the flux of these contaminants from source to deep-sea. Our results show that the difference between the behavior of the OMAs and the underlying superficial sediment is very important in the transport of carbon and persistent organic pollutants to the deep-sea. The Lisboa–Setúbal Canyon system is clearly exporting organic pollutants to the deep-sea through the transport of OMAs.