由于水和沉积物质量的恶化,人类福利和生物多样性处于危险之中。特别是,在过去的几十年里,由于快速的工业化和城市化,全球水和沉积物质量下降。本研究旨在确定9种重金属和准金属的浓度(Pb,Cr,Cd,Hg,As,Mn,Ni,Cu,和锌),并使用不同的污染指数评估生态风险(例如,重金属污染指数[HPI],内梅罗污染指数[NI],地质积累指数[Igeo],污染因子[CF],污染程度[CD]和污染负荷指数[PLI],生态风险指数[ERI])在Shitalakshya河的水和沉积物中,孟加拉国受工业影响的城市河流。第一次,在季风和干旱季节,在Shitalakshya河的更广泛地理区域收集了20个水和沉积物样品,并使用原子吸收光谱仪进行了分析。除季风季节的Cr(51.69ppb)和Mn(228.20ppb)外,水中重金属和准金属的平均浓度均在孟加拉国标准范围内,描绘潜在的生态和人类健康风险。此外,Mn的平均浓度(549.75和370.93ppb),镍(549.75和370.93ppb),两个季节沉积物中的Cu(45.34和36.09ppb)均高于国际标准,暗示水生沉积物生物群的风险。平均HPI值表明中度至高度污染,而NI值暗示着季风季节的污水,河流港口区域的污染严重。同样,Igeo,CF,CD,PLI阐明了沉积物中不同程度的污染,特别是在旱季。ERI值还表示干旱季节沉积物中的中等生态风险。总的来说,我们的发现突显了Shitalakshya河中令人震惊的重金属污染水平,必须立即采取行动保护水生环境,沉积物生物群,和人类健康。实践要点:这项研究确定了Shitalakshya河水和沉积物中重金属和准金属的浓度,孟加拉国。研究表明,水中Cr和Mn的平均浓度超过国家标准,而Mn,Ni,沉积物中的铜超过了国际限制。还使用不同的污染指数评估了重金属的潜在生态风险。计算的污染指数表明污染程度不同,暗示由于水环境和沉积物生物群中的重金属污染而导致的关键生态条件。
Human welfare and biodiversity are at risk due to the deterioration of water and sediment quality. Particularly, in last few decades, global water and sediment quality degraded due to the rapid industrialization and urbanization. This study aimed to determine the concentration of nine heavy metals and metalloid (Pb, Cr, Cd, Hg, As, Mn, Ni, Cu, and Zn) and assess the ecological risks using different pollution indices (e.g., heavy metal pollution index [HPI], Nemerow pollution index [NI], geo-accumulation index [Igeo], contamination factor [CF], degree of contamination [CD] and pollution load index [PLI], ecological risk index [ERI]) in water and sediment of the Shitalakshya River, an industrially affected urban river of Bangladesh. For the first time, 20 water and sediment samples were collected across a wider geographical area of the Shitalakshya River during both monsoon and dry seasons and analyzed using the atomic absorption spectrometer. Average concentrations of heavy metals and metalloid in water were within the Bangladesh standard except for Cr (51.69 ppb) and Mn (228.20 ppb) during monsoon season, portraying potential ecological and human health risks. Besides, average concentration of Mn (549.75 and 370.93 ppb), Ni (549.75 and 370.93 ppb), and Cu (45.34 and 36.09 ppb) in sediment during both seasons were above international standard, implying risk to aquatic sediment biota. The average HPI values indicated moderate to high contamination, whereas the NI values implied polluted water in monsoon season with severe pollution in port area of the river. Similarly, Igeo, CF, CD, and PLI elucidated different levels of contamination in the sediment, particularly during dry season. The ERI values also referred moderate ecological risk in the sediment during dry season. Overall, our findings highlight the alarming level of heavy metal pollution in the Shitalakshya River, necessitating immediate action to protect the aquatic environment, sediment biota, and human health. PRACTITIONER POINTS: This study determined the concentration of heavy metals and metalloid in water and sediment of the Shitalakshya River, Bangladesh. The study revealed that the average concentration of Cr and Mn in water exceeded national standard, whereas Mn, Ni, and Cu in sediment exceeded international limit. Potential ecological risk of heavy metals was also assessed using different pollution indices. Calculated pollution indices indicated different degree of pollution, implying critical ecological condition due to heavy metal pollution in aquatic environment and sediment biota.