Comparative study on toxicity evaluation of anaerobically treated parboiled rice manufacturing wastewater through fish bioassay.
Short term aquatic bioassay has been developed into a useful tool in water quality management. These tests give information on comparative toxicity of several compounds. The objective of this study was to evaluate the acute toxicity of raw and anaerobically treated effluents of the parboiled rice manufacturing industry. The acute toxicity test was carried out by using the fish Lebistes reticulatus under laboratory conditions. LC50 values for 24, 48, 72 and 96 hours ranged between 4.6 and 7.0% for the raw parboiled rice manufacturing wastewater. Two anaerobic fixed film fixed bed reactors and two different media matrices, i.e. UV stabilized Biopac media and Fugino spirals, were used for the treatment of parboiled rice mill wastewater. Effluents from these two reactors depicted LC50 values in the range of 68-88% and 62-78% for Biopac and Fugino spiral packed reactors, respectively. From the results, it is evident that anaerobically treated effluents from Biopac packed reactor is marginally better than Fugino spiral packed reactor. Results subjected to statistical evaluation depicted regression coefficient of more than 0.9 indicating good correlation between the mortality and effluent concentration.
Environmental Impact & Risk Assessment Division, National Environmental Engineering Research Institute (CSIR-NEERI), Nagpur 440020, Maharashtra, India.
Dipti Ramesh
DR
Giri
Environmental Impact & Risk Assessment Division, National Environmental Engineering Research Institute (CSIR-NEERI), Nagpur 440020, Maharashtra, India.
Ekta
E
Singh
Wastewater Technology Division, National Environmental Engineering Research Institute (CSIR-NEERI), Nagpur 440022, Maharashtra, India E-mail: dr_shantasa@rediffmail.com.
Shanta
S
Satyanarayan
D000693:Anaerobiosis; D000818:Animals; D001681:Biological Assay / Q000379:methods*; D005399:Fishes; D005511:Food Handling / Q000379:methods*; D007220:Industrial Waste / Q000032:analysis*; D023382:Toxicity Tests, Acute; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis
D007220:Industrial Waste; D062065:Wastewater; D014874:Water Pollutants, Chemical