The interactive effect of the season and estuary position on the concentration of persistent organic pollutants in water and sediment from the Cua Dai estuary in Vietnam.

The current study was conducted in the Cua Dai estuary, Vietnam, (1) to assess the status of persistent organic pollutants (POPs) and (2) to examine the interactive effect of season and estuary position on the concentration of the pollutants in surface water and sediment. Fifty-two water and sediment samples were taken in the dry and rainy seasons from inner- and outer-estuary positions to analyze for six POPs, including hexachlorocyclohexane isomers (HCHs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), heptachlor, aldrin, dieldrin, and polychlorinated biphenyl (PCBs). The averaged concentrations of the respective POPs in water samples were 0.