Assessment of toxic metals in water and sediment of Pasur River in Bangladesh

Abstract

This study was conducted to assess the levels of toxic metals like arsenic (As), chromium (Cr), cadmium (Cd), and lead (Pb) in water and sediments of the Pasur River in Bangladesh. The ranges of Cr, As, Cd, Pb in water were 25.76-77.39, 2.76-16.73, 0.42-2.98 and 12.69-42.67 μg/L and in sediments were 20.67-83.70, 3.15-19.97, 0.39-3.17 and 7.34-55.32 mg/kg. The level of studied metals in water samples exceeded the safe limits of drinking water, indicating that water from this river is not safe for drinking and cooking. Certain indices, including pollution load index (PLI) and contamination factor (C) were used to assess the ecological risk. The PLI indicated progressive deterioration of sediments by the studied metals. Potential ecological risks of metals in sediment indicated low to considerable risk. However, the C values of Cd ranged from 0.86 to 8.37 revealed that the examined sediments were strongly impacted by Cd. Considering the severity of potential ecological risk (PER) for single metal (E), the descending order of contaminants was Cd > Pb > As > Cr. According the results, some treatment scheme must formulate and implement by the researchers and related management organizations to save the Pasur River from metals contamination.

Quantifying Source Apportionment, Co‐occurrence, and Ecotoxicological Risk of Metals from Upstream, Lower Midstream, and Downstream River Segments, Bangladesh

“…High Cd concentrations in the sediments have been shown to be triggered by discharge from electrical plating, metal surface processing, and dying manufacturing industries (Xiao et al 2019). Ali et al (2018) also found that agrochemicals utilized in agriculture were a prominent source of Cd to sediment in this river basin.…”

“…Two Cd hot spots were observed in the northwestern part of the upstream segment at location S5, and in southwestern regions of the downstream segment, with locations S24 and S25 also having high weight for Cd and medium weight for Zn. The elevated Cd might be associated with Cd‐bearing electroplating and welding byproducts that enter the river water, triggering precipitation of contaminants sediment (Ali et al 2018; Niu et al 2020). Thus, it can be inferred that factor 3 is predominantly related to Cd deriving from an industrial point source.…”

“…In addition, when metals enter the water column, they are prone to collect in suspended particulate matter, which then sinks and accumulates in bed sediments (Zhang et al 2017). Sediment thus acts as a potential threat to the aquatic system via bioaccumulation of heavy metals deposited into the water column (Tamim et al 2016; Ali et al 2018; Khan et al 2019). These sediment‐derived metals can again settle in the water column through depositional ecosystem transformations (Liu et al 2020).…”

“…In Bangladesh, previous studies have focused on metal contamination status and qualitative analyses in a single river basin (Bhuiyan et al 2015, 2017; Islam et al 2015; Tamim et al 2016; Ali et al 2018; Proshad et al 2019). National basin–scale changes in Bangladesh due to metal contamination in sediment remain unexplored.…”

An index approach to heavy metal pollution assessment of Eme River, Umuahia, Nigeria

“…The surface water bodies are among the most sensitive sources that could be impacted by human activities which may result in degradation of the resource in the future (Afkhami et al, 2013;Roshan et al, 2013). Monitoring of heavy metal contamination in rivers is important because heavy metals pose threat to aquatic life, human health and to the environment due to biomagnification and their toxicity (Ahmed et al, 2015;Ali et al, 2016). The term ''heavy metals" refers to any metallic element that has relatively high density and applies to the group of metals and metalloids with atomic density greater than 5 g/cm 3 (Oves et al, 2012).…”