Kawser Ahmed and
Monirul Islam
Department of Fisheries
The Ganges-Brahmaputra-Meghna
(GBM) river system represents the most densely populated flood plain in the
world. The Ganges is polluted as it flows down from its source bearing
unforeseen environmental burden for the downstream. As a result aquatic pollution
specially trace metal pollution and POP’s has been identified in many rivers of the GBM systems.
Concentrations of POP’s in few species of marine
fish samples (Hilsa, Jew fishes, Pomfret and Shrimps) were collected from two downstream rivers
i.e., Pasur and Sibsa
of Sundarban mangrove forest and few areas of Bay
of Bengal coast, Bangladesh. Concentrations of POP’s from marine fishes of Bangladesh were found to be exceeded
the certified value. Elevated concentration of PCB, DDT and Heptachlor were
found in Peneaus indicus, Hilsa ilisha and Johnius belengerii. POP’s are widespread in the environment and are accumulating
in fish and wildlife as well as in the water and food chain to levels that
are having significant hormonal affects which can dramatically reduce the
reproductive success (number of eggs, hatching rate, and viability of embryos).
In some rivers and coastal areas, high loading of toxic trace elements and
POP’s has the potential to affect the entire population
of the species which in turn might bring some ecological changes.