RESUMO
Gas fields generate a significant volume of produced water, disposed in the vicinity of gas fields in Bangladesh after processing. It may have a variety of effects on ecology and the environment. This study was conducted to assess the contamination scenario and quality of produced and discharged water from gas fields in northeastern Bangladesh. The physicochemical analyses for this study were performed using standard procedures. Based on the outcomes of the analyzed samples, the current research employs a variety of indexing and statistical approaches to investigate the overall status of the studied water. The physiochemical analysis revealed high electrical conductivity (EC), total dissolved solid (TDS), salinity, and Na contents in both produced and discharged water. No severe cases have been identified, certain metals, such as Fe, Ni, and Cd, have been detected at levels high enough to impact specific index values in some cases. The results of the weighted contamination index (WCI) indicated mild to considerable pollution in the gas field region. The average score of potential ecological risk (PER) reflects minimal ecological risk. The heavy metal toxicity load (HTML) reveals negligible metal pollution in the studied water. The agricultural risk indices displayed increased sodium concentrations and EC, resulting in salinity and sodium risks. The magnesium absorption ratio is within the allowable range. In addition, the average heavy metal pollution index (HMPI) value demonstrates that the produced and discharged water is unsuitable for drinking. The entropy-based water quality index (EWQI) is below the threshold limit (<100) for all samples, indicating satisfactory water quality. This study is an early effort to evaluate the quality of wastewater produced and discharged from gas fields in Bangladesh. The findings of this research will provide valuable insights for future researchers and regulators in effectively managing and mitigating pollution from wastewater.
RESUMO
The study aims to assess the trace metals and physicochemical properties of water in the adjacent to the Sylhet gas blowout area. Trace metals were analyzed using atomic absorption spectrophotometer, whereas physicochemical parameters were evaluated in-situ state using portable instruments and also in the laboratory. Trace metals Pb, Cd, and Ni were found in the water samples higher than the acceptable limit by WHO standards, whereas the concentration of Cu and Zn were within acceptable limit, respectively. The correlation coefficient matrix and factor loading analysis spectacle that the interrelationship among the physicochemical parameters, trace elements, as well as other ions are moderate to strongly corellated which reflecting the homogeneous source of origin. According to contamination factor, Nemerow multi-factor index, pollution load index, and also, potential ecological risk index, the water of the region is quite polluted in case of Pb, Cd, and Ni but unpolluted for Cu and Zn. The water quality index indicates that treatment of water is required before using it for domestic purposes. The health quotient and hazard index results are less than standard value 1 suggesting that there is no noncarcinogenic risk in the area. The carcinogenic analysis shows that the lifetime incremental cancer risk mean value of Cd and Ni are fairly insignificant and Pb is more significant for children to cause health problem. The ILCR value of Cd and Ni are insignificant whereas Pb is significant to pose health risk for adults. Physicochemical parameters revealed that the water was slightly acidic and soft in nature implying to avoid the water from this area for drinking purposes. At the end, it can be concluded that this study will be useful for the residence as well as the policymaker to take the protective surveillance measures around the areas.