Physicochemical and Biological Analysis of Effluents of Fish Processing Industries at Rupsha, Khulna; Potential Source of Hazards to the Coastal Environment

Abstract

Fish processing plants use huge amount of fresh water for processing purpose. After processing, these huge amounts of water are discharged to the nature. The present study attempts to represent the characteristics of effluent form fish processing industries and probable impacts on coastal habitat and fishery sustainability. Water samples were collected from three different zones adjacent to Rupsha River where waste water is discharged in. Considering distances from the river three zones (Zone 1, zone 2 and Zone 3) were evaluated. Samples were collected from nature, adjacent to the corresponding zones both at low tide and high tide. The periodic physicochemical analysis of effluent to access the quality of effluent has been carried out in the laboratory. The parameters such as temperature, pH, TDS, TS, TSS, BOD, COD, chlorides, nitrate, bacterial count and plankton count of the water have been studied using international standard protocol. The physicochemical analysis reveals that all the samples are polluted having high chloride (14360 mg/l), BOD (62.37 mg/l) and TS (8000 mg/l) concentration which are higher than the permissible limits. The reading of the parameters of the discharged waste water are very high than the adjacent natural water bodies ( BOD 2.67 mg/l, COD 9.34 mg/l). Among three different zones Zone 2 is more causative to pollution. This study concludes that waste water from fish processing industries becomes a threat not only to the aquatic lives but also for human habitat.