Opencast coal mining results into formation of huge pit like void locally called khadan which eventually being filled with water serves as a reservoir of aquatic resources. Present study intends to explore the pisciculture potentiality in one abandoned Samdihi opencast coal pit using two economically important edible fish species, viz. Cirrhinus mrigala (mrigal) and Oreochromis niloticus (tilapia). Analysis of trace elements of fish samples were done by using energy-dispersive X-Ray fluorescence spectrometry, dominant potentially toxic metals of water and fish samples were done using atomic absorption spectroscopy, and basic nutritional evaluation through AOAC FAM (2012) and Lowry et al. (1951) protocols. The comparative analysis of trace elements, viz., sodium and potassium revealed that the fish from culture pond had slightly elevated concentrations compared to opencast coal pit bred fish and they ranged between 1116.54±1.54 and 3791.01±1.35 mg/kg and 5321.96±1.11 and 6797.96±2.78 mg/kg for sodium and potassium respectively. On the other hand, the comparative values of calcium and chloride revealed similar trends, where the opencast coal pit bred fish had higher concentrations (6658.46±2.03 to 9767.91±1.10 mg/kg for calcium and 3266.55±1.08 to 4238.54±1.71 mg/kg for chloride respectively) than fish from culture pond. Analysis of potentially toxic metals viz., cadmium, arsenic, lead and nickel of fish from opencast coal pit and culture pond revealed values within the standard FSSAI limit, where, cadmium concentration in mrigal and tilapia from opencast coal pit were much lower (0.25±0.02 and 0.24±0.02 mg/kg respectively) than fish from culture pond and similar trends were followed by arsenic, lead and nickel. The comparative study on nutritive components of fish from opencast coal pit and culture pond revealed that the total protein content, total carbohydrate and total fat content were within 77.20±0.25 and 85.82±0.40 mg/g, 1.75±0.02 to 4.14±0.15% and 14.42±0.34 and 18.51±0.42 mg/g respectively, where in most of the cases the opencast coal pit bred fish were found having a little higher values. Results revealed that there is no significant difference in comparing the macronutrients like sodium, calcium, potassium and chloride in fish from opencast coal pit and culture pond. Whereas, average values of potentially toxic metals (cadmium, arsenic, lead and nickel) concentration in opencast coal pit and culture pond were within the safe limits as per FSSAI, as well as lower values of target hazard quotient (THQ<1) predicting no potential risk of metal toxicity for human. Also, both the opencast coal pit and control pond bred fish maintained a good status in respect to protein, carbohydrate and fat content. In terms of estimated daily intake, estimated fish nutritional index, basic nutritional profiling and macronutrients study, the fish cultured in opencast coal pit showed relatively higher values than that of fish from culture pond. Thus, the current investigation features the intense potential of sustainable pisciculture in Samdihi abandoned opencast coal pit directing the sustainable development of socio-economy of local community along with environmental resource reclamation.
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