Seasonal investigation of heavy metals in marine fishes captured from the Bay of Bengal and the implications for human health risk assessment

To investigate the seasonal contamination levels and to evaluate the potential human health risks, ten heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Se, and Zn) were measured in ten different marine fish species from the Bay of Bengal during four seasons. The metal concentrations varied significantly (p 10) due to exposure to arsenic indicated that consumers remain at risk of cancer

Multivariate statistical analysis of metal contamination in surface water around Dhaka export processing industrial zone, Bangladesh

Deterioration of water quality by anthropogenic heavy metal pollution is a critical issue, especially in the least developed countries. This study, therefore, utilizes multivariate statistical approaches to report on the sources of heavy metals contamination in water bodies close to Dhaka Export Processing Zone industrial area in Bangladesh. Correlation matrix showed a number of significant associations (p < 0.01 and p < 0.05) among the metals, with no major seasonal influence on metal associations. Spatial variability of metal concentrations, however, was observed with lowering of concentration as distance increased from the pollution sources. Principal component and cluster analysis identified three major sources of metal pollution including untreated industrial effluents, municipal wastes, and atmospheric deposition of metals from burning of fossil fuels. These three sources were responsible for the data structure explaining 79.97% of total variance. Hierarchical cluster analysis demonstrated three clusters of nine sampling stations depending on the similarity of the data. Overall, the levels of metal concentrations determined in this study clearly illustrated the anthropogenic disturbances on water quality

Groundwater hydrogeochemistry and probabilistic health risk assessment through exposure to arsenic-contaminated groundwater of Meghna floodplain, central-east Bangladesh

A clear understanding of various hydrogeochemical processes is essential for the protection of groundwater quality, which is a prime concern in Bangladesh. The present study deals with the geochemistry of groundwater at various depths to investigate the hydrogeochemical processes controlling the water quality of Meghna floodplain, the sources and mechanisms of arsenic (As) liberation, and the estimation of carcinogenic and non-carcinogenic health risks (using probabilistic and deterministic approaches) to the adults and children of the Comilla district, central-east Bangladesh. The groundwaters were generally of Ca–Mg–HCO type, and water-sediment interaction was the dominant factor in evolving the chemical signatures. The dissolution of carbonates, weathering of silicates, and cation exchange processes governed the major ion chemistry. Dissolved As concentration ranged from 0.002 to 0.36 mg/L and Monte Carlo simulation-based probabilistic estimation of cancer risk suggested that; (1) ~ 83% of the waters exceeded the higher end of the acceptable limit of 1 × 10; (2) the probability of additional cases of cancer in every 10,000 adults and children were on average ~9 and ~5, respectively; (3) adults were more susceptible than children; and (4) ingestion was the main pathway of As poisoning and the contribution of dermal contact was negligible

Study on heavy metals levels and its risk assessment in some edible fishes from Bangshi River, Savar, Dhaka, Bangladesh

Concentrations of eight heavy metals (Pb, Cd, Ni, Cr, Cu, Zn, Mn, and As) in the muscles of ten species of fish collected from Bangshi River at Savar in Bangladesh were measured in two different seasons. The concentrations of the studied heavy metals, except Pb in Corica soborna, were found to be below the safe limits suggested by various authorities and thus gave no indication of pollution. The present study also showed that, Zn was the most and Cd was the least accumulated metal in the studied fish muscles. ANOVA analysis clearly revealed that there was a significant variation (Cl = 95%) of the heavy metal concentrations in different fish species in the Bangshi River. Significant positive correlations between the heavy metal concentrations in fish muscles were also observed in both seasons. From the human health point of view, this study showed that there was no possible health risk to consumers due to intake of studied fishes under the current consumption rate. Crown Copyright (C) 2012 Published by Elsevier Ltd. All rights reserved

Potential ecological risk assessment of heavy metal contamination in sediment and water body around Dhaka export processing zone, Bangladesh

Sediments and surface water contamination by the industrial effluents containing heavy metals is the most detrimental environmental impact. Therefore, the present work attempts to determine the status of eight heavy metal distribution in sediments and water samples, and their ecological risks' assessment in the studied area. The distribution pattern of heavy metals in the water and sediment follows the sequences: Zn > Cu > Pb > Cr > Mn > Ni > As > Cd and Mn > Zn > Cr > Pb > Cu > Ni > As > Cd, respectively. Gross water pollution is observed at different sampling points of Dhalai Beel and Bangshi River. The comparison of sedimentary mean metal concentrations with several environmental contamination monitoring parameters, viz, threshold effect level (TEL), probable effect level (PEL), and severe effect lever (SEL) indicates that the metal levels are less than PEL except Cr. Moreover, the level of contamination degree (C (d)) and modified degree of contamination (mC (d)) indicates 'low' and 'nil to low' degree of contamination, respectively. Pollution load indices (PLI) of the studied area are lower than unity, indicates no pollution. Furthermore, a toxic-response factor is applied to assess the potential ecological risk of these heavy metals into the water body. The results of this study exhibit a low potential ecological risk of heavy metals. The Pearson's correlation and cluster analysis are also performed to assess the heavy metal interactions in water and sediment samples

Heavy metals in fish, fruits and vegetables from Rajshahi, Bangladesh: a statistical approach

Vegetables, fruits, and fishes are the main routes of exposure to heavy metals formost of the Bangladeshi population.Thus, the present study was conducted to determine the content of lead (Pb),manganese (Mn), chromium, (Cr), cadmium (Cd), and arsenic (As) in some keyvegetables, fruits, and fishes purchased from the city market of Rajshahi using atomicabsorption spectrometry.The Pb, Mn, Cr, Cd, and As concentrations ranged from 0.42 to 23.99, 1.13 to 8.11,0.17 to 2.50, 0.15 to 3.02, and 0.07 to 0.15 mg/kg dry weight respectively. The estimatedamounts of heavy metals were lower than the recommended values, but considerableattention should be paid to the Pb and Cd concentrations. Especially, among five heavymetals in three food categories, fish samples were highly contaminated by Pb. The resultsrevealed that the estimated daily intakes of heavy metals were within the respectiverecommended daily dietary allowance established internationally. The biggestcontribution of daily intakes of heavy metals came from the vegetables, which could bedue to its high consumption rate.Results of one way ANOVA test demonstrated that heavy metal concentrations werestatistically significant (p < 0.05) among the different vegetable, fruit, and fish species. Furthermore, no significant correlation was found between the heavy metals invegetables, fruits, and fishes except Pb-Cd (r = 0.899, α = 0.05) in fruits

Assessment of the ecological risk from heavy metals in the surface sediment of River Surma, Bangladesh: coupled approach of Monte Carlo simulation and multi-component statistical analysis

River sediment can be used to measure the pollution level in natural water, as it serves as one of the vital environmental indicators. This study aims to assess heavy metal pollution namely Copper (Cu), Iron (Fe), Manganese (Mn), Zinc (Zn), Nickel (Ni), Lead (Pb), and Cadmium (Cd) in Surma River. Further, it compares potential ecological risk index values using Hakanson Risk Index (RI) and Monte Carlo Simulation (MCS) approach to evaluate the environmental risks caused by these heavy metals. in the study area. With obtained results, enrichment of individual heavy metals in the study area was found in the order of Ni > Pb > Cd > Mn > Cu > Zn. Also, variance in MCS index contributed by studied metals was in the order of Cd > Pb > Ni > Zn > Cu. None of the heavy metals, except Ni, showed moderate contamination of the sediment. Risk index values from RI and MCS provide valuable insights in the contamination profile of the river, indicating the studied river is currently under low ecological risk for the studied heavy metals. This study can be utilized to assess the susceptibility of the river sediment to heavy metal pollution near an urban core, and to have a better understanding of the contamination profile of a river.Asia Pacific Network (APN) Collaborative Regional Research Programme | Ref. CRRP2019-01MY-Kuma

Evaluation of Water Quality for Sustainable Agriculture in Bangladesh

Sustainable groundwater quality has become a major concern for the agro-based country like Bangladesh. Integrated approaches of various irrigation water quality indices and geostatistical modeling were applied to evaluate the suitability and for spatial mapping of groundwater quality of Faridpur District in central Bangladesh. The irrigation water quality index (IWQI) revealed that majority of the samples were suitable for irrigation. Similar outcomes were recorded from other indices including Na%, sodium adsorption ratio (SAR), residual sodium bicarbonate (RSBC), total hardness (TH), Kelley's ratio (KR), and magnesium adsorption ratio (MAR). Classifications based on Wilcox diagram and permeability index (PI) plot indicated a similar conclusion wherein almost all the samples were safe for agricultural uses without posing considerable effect on the soil fertility and overall crop yield. Principal component analysis (PCA) grouped the major cations and anions into three principal components including dissolution of calcite minerals, leaching of silicate sediments, and ion exchange process. Spatial mapping of IWQI identified that groundwater in the northern side of Faridpur region were more suitable for irrigational uses relative to central and southern side, possibly due to gradients of domestic discharges and agricultural activates from north to south side. These findings would provide useful information to water distributors, managers, and decision makers for taking adaptive measures in irrigation water quality management systems

Industrial metal pollution in water and probabilistic assessment of human health risk

Concentration of eight heavy metals in surface and groundwater around Dhaka Export Processing Zone (DEPZ) industrial area were investigated, and the health risk posed to local children and adult residents via ingestion and dermal contact was evaluated using deterministic and probabilistic approaches. Metal concentrations (except Cu, Mn, Ni, and Zn) in Bangshi River water were above the drinking water quality guidelines, while in groundwater were less than the recommended limits. Concentration of metals in surface water decreased as a function of distance. Estimations of non-carcinogenic health risk for surface water revealed that mean hazard index (HI) values of As, Cr, Cu, and Pb for combined pathways (i.e., ingestion and dermal contact) were >1.0 for both age groups. The estimated risk mainly came from the ingestion pathway. However, the HI values for all the examined metals in groundwater were 1\ua0×\ua010 for adult and children, respectively. Deterministic and probabilistic estimations of cancer risk through exposure to groundwater were well below the safety limit. Overall, the population exposed to Bangshi River water remained at carcinogenic and non-carcinogenic health threat and the risk was higher for adults. Sensitivity analysis identified exposure duration (ED) and ingestion rate (IR) of water as the most relevant variables affecting the probabilistic risk estimation model outcome

Efficiency analysis of eggshell and tea waste as Low cost adsorbents for Cr removal from wastewater sample

This study aims to assess the efficiency of two agricultural wastes as adsorbents to remove Chromium (Cr) from a wastewater sample. Chromium-containing wastewater was treated with calcined and non-calcined eggshell and biochar tea waste with the adsorption method, and the effect of contact time, pH, and adsorbent dosage were investigated to examine the efficiency. The results indicate that 120 min is sufficient for the biochar tea waste and the non-calcined eggshell to reach adsorption equilibrium, where the calcined eggshell was reached equilibrium at 30 min. The optimal pH of all adsorbents was found to be 5, which indicates the interference of H+ ions on removing metal ions at low pH. Pseudo-first order and pseudo-second-order kinetic models were studied to assess the kinetic adsorption mechanism. Results also reveal that an increasing amount of adsorbent dose improves the removal efficiency of the adsorbent. The removal rates of using 2.0 g of non-calcined eggshell, 1.5 g of calcined eggshell and 2.5 g of biochar tea waste were found to be 70.70%, 100%, and 68.2%, respectively. The results show that the adsorption can be more appropriately described by the pseudo-second-order kinetic model for the adsorption of chromium ions from the wastewater. The findings of this study suggest that using these adsorbents, industrial wastewater can be treated in a more cost-effective and simple way than other existing methods