Occurrence of organochlorine insecticides, PCBs and PCB congeners in waters and sediments of the Ebro River (Spain)

Organochlorine insecticides and poychlorinated biphenyls (PCBs) were measur ed in water and sediment samples taken from thirteen sites along the Ebro R iver (Spain), the most agricultural and industrial basin in the North of th e Iberian Peninsula. Concentrations of 10 insecticides, PCBs and 13 PCB con geners were determined; grouping all chemicals by structural affinity, thes e can be arranged in descending order as follow: PCBs > total DDT > total c yclodiene insecticides > total HCH. Higher levels of organochlorine polluta nts were detected in sediments from the middle and lower parts of the strea m where are located the main important inputs in Ebro River. (C) 1998 Elsev ier Science Ltd. All rights reserved.