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In recent decades, anthropogenic activities have resulted in road dust and roadside soil hosted metal(oid)s pollution in the urban environment. In the South-Asian megacity "Dhaka", schools are situated in the areas with high population density and high traffic emissions. As the school-going children are the most vulnerable receptor, school premises in Dhaka city represent an important yet overlooked exposure point to contaminated dust and soil. Therefore, the present study investigated the metal(oid)s (Cu, Pb, Zn and As) pollution in dust and soil at school compounds, explored their possible sources and estimated the associated human health risk. This study revealed that dust contained higher concentration of metal(oid)s than soil, and the Azimpur Govt. Girls School & College was identified as the most contaminated site. The enrichment of school dust with Cu, Zn and Pb were strictly related to the dense population and substantial traffic activity in the study areas. Arsenic content in school soil was several folds higher than its concentration in the upper crust. Natural and anthropogenic activities possibly posed a synergistic effect on such high soil As. The multivariate statistics suggested that Cu, Zn and Pb were likely to be originated from traffic-related activities, while Zr, Fe, Ti and Rb from natural sources, and K, Sr and Ca from industrial activities. The assessment of health risk suggested the children as a vulnerable receptor and ingestion was identified as the dominant pathway of dust and soil exposure. The hazard index (HI) values were lower than unity, suggesting no possible non-cancer health risk. Arsenic posed a lifetime carcinogenic risk to the population in the study area through soil ingestion and dermal adsorption. [ABSTRACT FROM AUTHOR]

Despite the benefits of seafood's consumption, the bioaccumulation of metals in fish can endanger consumers' health. This study analyzed lead (Pb), mercury (Hg), Arsenic (As), and Cadmium (Cd) concentrations in fillet and gill of parrotfish ( Scarus ghobban ) using flame atomic adsorption spectroscopy (FAAS). The potential non-carcinogenic and carcinogenic health risks due to consumption of Scarus ghobban fillet were assessed by estimating average target hazard quotient (THQ) and total target hazard quotient (TTHQ) and Incremental Lifetime Cancer Risk cancer risk (ILCR) of the analyzed metals. This study indicated that Cd, Pb, As and Hg concentrations were significantly ( p  < 0.05) lower than Food and Agriculture Organization (FAO) and national standard limits. The meal concentrations (μg/kg dry weight) in both fillet and gill were ranked as follows Pb > Cd > As > Hg. THQ and TTHQ were lower than 1 for adults and children, indicating that consumers were not at considerable non-carcinogenic risk. However, ILCR value for As was greater than 10 −4 , indicating that consumers are at carcinogenic risk. Overall, this research highlighted that although the consumption of parrotfish from the Persian Gulf does not pose non-carcinogenic health risks, carcinogenic risks derived from toxic As can be detrimental for local consumers. [ABSTRACT FROM AUTHOR]

One of the most important pathways for exposure to metals is drinking water ingestion. Chronic or acute exposure to metals can endanger the health of the exposed population, and hence, estimation of human health risks is crucial. In the current study for the first time, the concentrations of Mercury (Hg), Arsenic (As), Zinc (Zn), Lead (Pb) and Cobalt (Co) in 120 collected tap water samples (2015, July–November) from Ilam city, Iran were investigated using flame atomic absorption spectrophotometer. Also, the metal-induced carcinogenic and non-carcinogenic risks for consumers exposed to tap drinking water were calculated. The average (range) concentrations of Hg, Zn, As, Pb and Co were defined as 0.40 ± 0.10 μg/L (ND-0.9 μg/L), 5014 ± 5707 μg/L (2900.00–5668.33 μg/L), 21.008 ± 2.876 μg/L (3.5–62 μg/L), 30.38 ± 5.56 μg/L (6–87 μg/L), and 11.34 ± 1.61 μg/L (0.1–50 μg/L), respectively. Average concentrations of all examined metals were significantly higher than WHO and national standard recommended limits. The ranking order of metals concentrations in the tap drinking water was Zn > Pb > As > Co > Hg. Except for Hg and Co, at least one age group consumers were at considerable non-carcinogenic risks induced by Zn, As and Pb [Target Hazard Quotient (THQ > 1)]. The rank order of age groups consumers based on THQ and Incremental lifetime cancer risk (ILCR) was <1 years >1–9 years > 20 + years > 10–19 years. The calculated ILCR for As in all age groups were higher than 10 −3 value. All age groups of consumers in Ilam city, especially infants (<1 years) and children (1–10 years), are at considerable non-carcinogenic and carcinogenesis risk. [ABSTRACT FROM AUTHOR]

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 < 0.05) among the fish species with maximum and minimum accumulation of Zn (46.47 μg/g) and Cd (0.25 μg/g), respectively. The fishes captured during summer accumulated a higher amount of metals relative to other seasons, which was attributed to a higher influx of agricultural waste, sewage and sludge by heavy rainfall and floods. According to estimated daily intake (EDI), target hazard quotient (THQ), total target hazard quotient (TTHQ), and the permissible safety limits prescribed by various agencies, consumption of the examined fish species should be considered as safe for human health. However, the estimation of carcinogenic risk (CR > 10 −5 ) due to exposure to arsenic indicated that consumers remain at risk of cancer. [ABSTRACT FROM AUTHOR]

The Karnaphuli River is one of the prime and most important streams in the southeastern part of Bangladesh. The favorable water current and the geographic location have rendered the Karnaphuly River estuary a suitable habitat and a breeding ground for diverse fish species. Reversely, this estuary has been polluted by discharges from many point and non-point sources due to its location in the catchment area of a heavily industrialized area, Chattagram port city. However, published research concerning the status of toxic and trace elements in some commercially important benthic and pelagic coastal fish species in Karnaphuli River estuary was not found in the existing literature. Therefore, it's an important field of study on the assessment of toxic and trace elements concentration in the commercially important benthic and pelagic coastal fish species and their health taxation in the Karnaphuli River Estuary. Energy dispersive X-ray fluorescence (ED-XRF) was used to quantify trace metal concentration in edible parts of the fish species. This study revealed that the rank of the trace metals concentration was as follows (mg/kg): Zn (37.1) > Mn (16.12) > V (11.16) > Cu (9.49) > Rb (5.62) > Pb (2.98) > Cr (1.59) > Co (1.17). The F -test showed that a significant difference at 95 % confidence level in the distribution pattern of trace metals concentration among the examined fish species in the study area. The metal pollution index (MPI) in the muscle of fishes were found to be in the following order: L. bata > P. monodon > T. cirratus > M. bleekeri > O. pabda > H. nehereus > L. calcarifer > P. argenteus > P. paradiseus > T. toli , and the MPIs for most of the benthic fish species were higher compared to the pelagic fishes. On the other hand, the examined fish species were significantly bio-accumulative with the highest bio-accumulation factor value for benthic species. The multivariate analysis identified that the sources of the trace metals were associated with anthropogenic activities. For the human health risk assessment concern, estimated daily intake, target hazard quotient and cancer-causing risk were estimated. The results for non-cancer hazardous index values were found to be lower than unity. On the other hand, the total cancer risk data ranging from 1.24E−05 to 1.70E−05 were fallen within the range for the threshold values (1.0E−06 to 1.0E−04). However, considering the suggested values set by the environmental and regulatory agencies, it has been recommended that no significant non-carcinogenic and cancer-causing health risk for humans was seen due to the consumption of the studied fish species. [Display omitted] • Rank of the trace metals conc. in fishes was as follows: Zn > Mn > V > Cu > Rb > Pb > Cr > Co. • The MPI values of benthic fishes were greater than the pelagic fishes in Karnaphuly River. • EDI for Pb, Zn, Mn, and Co in fishes were higher than the TDI values, while lower for Cr and Cu. • Non-carcinogenic risks (THQ and HI) were found to be lower than the unity (HI < 1). • Carcinogenic risk suggests that consumption of the fishes pose a low risk to consumer. [ABSTRACT FROM AUTHOR]

Considering the human health risk due to the consumption of foodstuffs, the concentrations of heavy metals (lead, manganese, chromium, cadmium, and arsenic) are investigated in vegetables, fruits, and fish species collected from the central market (called Shaheb Bazar) of Rajshahi City, Bangladesh. The foodstuffs examined for metal constituents are the basis of human nutrition in the study area. The highest concentrations of Mn and As in vegetables (onion and pointed gourd, respectively), Cr and Cd in fruits (black berry and mango, respectively), and Pb in fish (catla) are recorded. Health risks associated with these heavy metals are evaluated due to dietary intake. Target hazard quotient (THQ) and hazard index (HI) are calculated to evaluate the non-carcinogenic health risk from individual and combined heavy metals. The THQ values for individual heavy metals are below 1, suggesting that people would not experience significant health risks if they ingest a single heavy metal from one kind of foodstuff (e.g., vegetables). However, consumption of several of the foodstuffs could lead a potential health risk to human population since HI value is higher than 1. The relative contributions of vegetables, fishes, and fruits to HI are 49.44, 39.07, and 11.53 %, respectively. Also, the relative contributions of Pb, Cd, As, Mn, and Cr to HI are 51.81, 35.55, 11.73, 0.85, and 0.02 %, respectively. The estimation shows that the carcinogenic risk of arsenic exceeds the accepted risk level of 1 × 10. Thus, the carcinogenic risk of arsenic for consumers is a matter of concern. [ABSTRACT FROM AUTHOR]

This study is an attempt to assess the extent of toxic metals, including Pb, Cd, Cr, Mn and As in groundwater and some cereals collected from Shibganj area of Chapai Nawabganj, Rajshahi, Bangladesh. The chemical results of groundwater show that the mean concentrations of Pb, Cd and Mn exceed the values of WHO, USEPA as well as Bangladesh Drinking Water Standards. However, As content is within the permissible limits in terms of Bangladesh Drinking Water Standards, but exceeds the WHO and USEPA values. Cr is in negligible quantity in the examined groundwater samples. Results reveal wide variation in toxic metal content among the three cereal samples. In general, the mean toxic metal concentrations in cereals (rice, wheat and urid bean) are lower than the respective established safe limits for these elements, except for lead concentration in all samples. [ABSTRACT FROM AUTHOR]

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 3 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 × 10−4; (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 (<1%). According to sensitivity analysis, the duration of exposure to As and its concentration in groundwater posed the greatest impact on cancer risk assessment. However, hydrogeochemical investigations on the sources and mobilization mechanisms of As suggested that the reductive dissolution of Fe and Mn oxyhydroxides was the principal process of As release in groundwater. The oxidation of pyrite and competitive exchange of fertilizer-derived phosphate for the sorbed As were not postulated as the plausible explanation for As liberation. • Weathering of carbonates and silicates, and cation exchange control major ion chemistry. • First simulation based cancer risk assessment of As. • Water ingestion is the main pathway of contaminated groundwater As exposure. • Duration of As exposure and its concentration exert greatest control on caner risk. • Reduction of Fe and Mn oxides regulates As mobilization. [ABSTRACT FROM AUTHOR]

Abstract: 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 (CI=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. [Copyright &y& Elsevier]