PBDEs and PCBs in sediments of the Thi Nai Lagoon (Central Vietnam) and soils from its mainland

► Levels and patterns of PCBs, PCB 11, and PBDEs in surface sediments and soils. ► Main natural and anthropogenic processes in tropical areas are changing rapidly. ► Key processes are identified by salinity, porosity and grain size patterns. ► PCBs, PCB 11 and PBDEs levels are similar to those found far from direct sources. ► Efficacy of degradation processes are confirmed by congener patterns and statistics.