Polychlorinated Biphenyls (PCBs) in a Sub-tropical Marine Environment: A Case study in Seawaters Collected around Ryukyu Islands, Japan

Abstract

Seawater samples collected around Ryukyu Islands during the Nagasaki Maru expedition in September 22 to October 2, 2001 were analyzed for total PCBs and some nutrients. The PCBs were detected in all stations (W-1 to W-4), in concentrations ranging between 0.053-0.28ngL-1. The concentration of PCBs increased from surface water down to 600m, thereafter decreasing with depth to 1200m at W-4. At W-1, PCBs increased from surface water down to 55m. Chromatogram patterns varied among the sampling stations, implying the possibility of having different compositions of PCBs. The trend of the nutrients (phosphates and silicates) showed a general increase with depth.