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The global concern over trace and heavy metal contamination in aquatic environments necessitates the development of effective remediation strategies. Using aquatic plants for heavy metal removal is a relatively economical and sustainable technology worldwide. This study involved collecting sediment and aquatic plant samples (Acanthus ilicifolius, Typha elephantina, and Cynodon dactylon) from a highly urbanized estuary to analyze metal concentrations in sediment, assess ecological risks, and explore the phytoremediation potential. Trace and heavy metals were detected using Energy Dispersive X-ray Fluorescence Spectroscopy (EDXRF). The sediment metal concentrations were found in decreasing order of Fe, Ti, Mn, Rb, Zr, Zn, Sr, Cu, Co, and As. Fe, Sr, and As concentrations were below certified values, whereas Cu, Zn, and Rb exceeded them. Cumulatively, the pollution load index (PLI) values were close to 1 (0.845), indicating that the study area is likely experiencing metal pollution. The Contamination Factor (CF) values, ranging from 1 to 3, indicated a moderate degree of sediment pollution for Ti, Mn, Cu, Zn, and Rb. The Enrichment Factor (EF) values similarly showed moderate enrichment for these metals, with Cu exhibiting the highest degree of enrichment. Ecological risk assessment highlighted the only metal, Cu, as posing the greatest risk among the studied metals. In terms of phytoremediation potential, the bioconcentration factor (BCF) followed the decreasing order of C. dactylon > A. ilicifolius > T. elephantina for most metals, with low BCF values (<1) indicating low accumulator potential. However, the translocation factor (TF) values for Zn (1.464) and Rb (1.299) in A. ilicifolius species were greater than 1, indicating low accumulation potential but hyper-metabolizing capabilities, allowing the plant to accumulate metals in its aerial parts, making it effective for phytostabilization. [ABSTRACT FROM AUTHOR]

The study assessed the composition, health risk, and sources of trace elements of road dust collected from three major metropolitan cities in Bangladesh. Pellets were prepared from the collected road dust samples and analyzed by the Energy Dispersive X-ray Fluorescence. The mean concentration of trace elements showed the order of K > Fe > Ca > Ti > Mn > Zr > Sr > Zn > Rb > Cr > Rb > Cu > Pb > Y > As > Ni. This research also presented the spatial distribution of the metals among three cities. The contamination factor and degree of contamination were assessed. The highest contamination factor was observed near BSRM steel manufacturing company, Chattogram could be due to the increased traffic in front of this industry. All the sampling sites showed pollution load index lower than one indicating unpolluted. However, K, Zn, and Zr showed a pollution load index values more significant than one. The result indicated that the ecological risk factor (Er) values fluctuated among metals tested across metropolitan cities. Negative geo-accumulation indexes were found for all the elements except K and Zn, suggesting moderate pollution. The Hazard Quotient values of all metals are < 1 for both adults and children. The cancer risks associated with Cr, Co, Ni, As, and Pb have been estimated individually for children and adults. The cancer risks associated with trace elements are below the European Union's acceptable limit, indicating that these five elements are not carcinogenic. The findings of principal component analysis followed by multiple linear regression showed that the sources of heavy metals were mixed natural (34.25%) and anthropogenic sources, vehicle emissions (38.92%), natural sources (5.80%), industrial sources (11.02%) and agricultural sources (10.02%). Four factors were concluded as sources of heavy metals confirmed by applying the positive matrix factorization model such as anthropogenic, industrial activities, natural process and agricultural activities. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigated the contamination status and health risk of potentially toxic elements (PTEs) such as Hg, As, Pb, Fe, Zn, and Cu in four selected fish species from one of the largest wetlands in South Asia. The results showed that the degree of contamination varied among the fish species, with Fe being the most abundant PTE, followed by Zn, Cu, Pb, As, and Hg. Among the fish species, Glossogobius giuris had the highest Hg concentration, while Nandus nandus predominantly accumulated As. Health risk assessment showed the PTEs posed no substantial risks to consumers. The carcinogenic risks (CR) derived from Pb intake were also below the standard limit, further supporting the conclusion that the consumption of the studied fishes did not pose a potential health harm to consumers. Overall, the study provided evidence that, at the existing consumption rate, the analyzed fish species from the freshwater are safe to consumers. Potentially toxic elements (PTEs) such as Hg, As, and Pb have become concentrated in the aquatic ecosystem as a result of increased human activities. However, these substances frequently have synergistic or antagonistic effects on the human body or other animals. As a result, there are concerns world-wide that commercially available food products, especially fish, may be contaminated with hazardous elements. In this study, samples of four selected fishes, Gutum (Lepidocephalichthys guntea), Baim (Macrognathus pancalus), Baila (Glossogobius giuris), Meni (Nandus nandus) were analyzed from one of the largest freshwater wetlands (designed as a Ramsar Site) in South Asia to evaluate PTEs contamination status and human health risk assessment. The result demonstrated that the degree of contamination for six PTEs decreased in the following sequences for fish: Fe > Zn > Cu > Pb > As > Hg. The edible part of G. giuris had the maximum value for Hg (0.42 μg/g dw), while N. nandus predominantly accumulated As (<0.41 μg/g dw). The estimated daily intake (EDI) values ranged from 0.003 to 1.75, which was much lower than the recommended values. The hazard index (HI), THQ, total target hazard quotient (TTHQ) scores through consuming fish followed the decreasing order of Fe > Hg > Cu > Zn > Pb. The values for each index were less than 1, indicating that there were no substantial health risks for the consumers. The carcinogenic risks (CR) derived from the intake of Pb ranged from 4.92 × 10−8 to 4.14 × 10−8 for males and 5.45 × 10−8 to 4.59 × 10−8 for females, which also did not exceed the standard limit (1.00 × 10−6). This study demonstrated that, under the existing consumption rate, there was no potential health harm to consumers from consuming the studied fishes. This study offers a chance to regularly check PTEs in this environment, reducing the contamination of heavy metals. [ABSTRACT FROM AUTHOR]

The coastal zone of Bangladesh, with a population density of 1278 people per square kilometer, is under serious threat due to heavy metal pollution. To date, many studies have been conducted on the heavy metal contamination in soils, water, aquatic animals, and plants in the coastal zone of Bangladesh; however, the available information is dispersed. In this study, previous findings on the contamination levels, distributions, risks, and sources of heavy metals in sediments and organisms were summarized for the first time to present the overall status of heavy metal pollution along coastal regions. Earlier research found that the concentrations of various heavy metals (HMs), particularly Co, Cd, Pb, Cu, Cr, Mn, Fe, and Ni in water, sediment, and fish in most coastal locations, were above their permissible limits. High concentrations of HMs were observed in sediments and water, like Cr of 55 mg/kg and 86.93 mg/l in the ship-breaking areas and Karnaphuli River, respectively, in coastal regions of Bangladesh. Heavy metals severely contaminated the Karnaphuli River estuary and ship-breaking area on the Sitakundu coast, where sediments were the ultimate sink of high concentrations of metals. Sedentary or bottom-dwelling organisms like gastropods and shrimp had higher levels of heavy metals than other organisms. As a result, the modified PRISMA review method was used to look at the critical research gap about heavy metal pollution in Bangladesh's coastal areas by analyzing the current research trends and bottlenecks. [ABSTRACT FROM AUTHOR]

In this study, we combined atmospheric pressure cold plasma, a novel treatment technology, with an absorption technique with soybean husk to remove Pb and Cd from milk. Different combinations of treatment duration, voltage, and post treatment retention time were used to determine the effectiveness of cold plasma. Soybean husk was used for metal extraction, and it was observed that when the milk samples were plasma treated with a discharge voltage of 50 kV for 2 min and held for 24 h, the highest mean elimination of about 27.37% for Pb and 14.89% for Cd was obtained. Reactive oxygen and nitrogen species produced from plasma treatment were identified using Optical Emission Spectra analysis. A high voltage of 50 kV plasma for a 2 min duration could produce 500 ± 100 ppm of ozone concentration inside the treated package. The value of ΔE, which indicates overall color difference measurement, was significantly (p < 0.05) higher in all the treated samples than control samples. However, in the frequency range from 0.01 to 100 Hz, there was not much difference between the control and treated sample in the frequency sweep test. The identified functional groups at different wavenumbers (cm−1) in the treated samples were found to be similar compared to the control samples. [ABSTRACT FROM AUTHOR]

In recent decades, water quality is a great concern for the human being as it is the most important natural resource but water is polluted by increasing population activities. In this study, surface water samples were collected in the wet and the dry season from Halda River, Bangladesh, and 12 physicochemical properties and 10 traces elements (Cd, Cr, Mn, Fe, Co, Cu, Zn, As, Pb, and Hg) were analyzed to assess the metal toxicity, identify the possible sources, and determine possible carcinogenic and noncarcinogenic risk for adults and child residents. During wet season, the mean concentrations of Cd, Cr, Mn, Fe, Co, Cu, Zn, As, Pb, and Hg were 0.032 ± 0.028, 0.004 ± 0.002, 0.010 ± 0.012, 0.38 ± 0.08, 0.010 ± 0.017, 3.33 ± 1.16, 0.062 ± 0.008, 1.34 ± 1.17, 0.030 ± 0.014, and 0.007 ± 0.002 mg/L, respectively, whereas the concentrations were measured as 0.04 ± 0.017, 0.060 ± 0.036, 0.150 ± 0.134, 0.58 ± 0.11, 0.049 ± 0.017, 0.172 ± 0.166, 0.393 ± 0.212, 1.07 ± 0.989, 0.104 ± 0.121, and 0.003 ± 0.002 mg/L, respectively, during the dry season. The levels of trace elements in water samples were much higher than the guideline values for safe limits of drinking water and the protection of freshwater aquatic life, indicated that water from this river is not safe for drinking and/or cooking purposes. Trace element evaluation index indicated that water was found to be high contamination while ecological risk index showed low to very high contamination. All hazard quotient and hazard index (HI) values were higher than the risk threshold of unity. HI values for child were higher than those for adult, indicating that the health of children is at dramatically higher risk than adults. Arsenic for water ingestion and dermal pathways was the primary contributors to total health risk (HI/THI) indicated that As in surface water of the Halda River might pose health risks to residential users. [ABSTRACT FROM AUTHOR]

The surface salt marsh sediments from marine ecosystems in the Bay of Bengal, Bangladesh was assessed for trace elements like iron (Fe), calcium (Ca), titanium (Ti), potassium (K), strontium (Sr), rubidium (Rb), zirconium (Zr), zinc (Zn), copper (Cu) and lead (Pb), their potential sources, and associated ecological risks. The range of trace elements in sediment (mg/kg) followed the decreasing order: Fe (25020–35176) > Ca (8679–16323) >Ti (2678–3340) > K (23680–16770) > Sr (138.32–209.64) > Rb (124–186.57) > Zr (96.21–161.35) > Zn (37.71–44.95) > Cu (36.51–51.66) > Pb (1.35–10.42). The concentrations of trace elements were under the average shale values of metals in sediment except for Fe, Cu and Rb, which can occasionally be associated with adverse biological effects. Contamination level and ecological risk were evaluated using contamination factor (CF), enrichment factor (EF), geo-accumulation index (Igeo), pollution load index (PLI), and potential ecological risk index (PERI). Multivariate statistical technique was used to classify the metal sources. The results showed that Fe was significantly enriched in the sediments. Ecological risk factors illustrated a pollution-free condition of the salt marsh ecosystem in Bangladesh. [ABSTRACT FROM AUTHOR]

A study was conducted on 16 sites in four Ramsar designated wetlands soils regarding soil properties and pollution indices in the Sylhet basin of Bangladesh. The wetlands sites' soil quality remained favorable for agricultural sustainability. Arsenic and cadmium contents were found at minimum detection levels. Rubidium and zirconium were found below critical levels. Pollution indices revealed that zinc and titanium content is slightly higher than the other elements. It was observed that Fe, Ti, Zr, and Mn originate from natural sources or sediments. In contrast, Zn and Cu originate from the artificial fertilizer sources used in and around agricultural lands of the wetland bodies. Moreover, the wetlands are used only for Boro rice crop, and for most of the year, they remain fallow. As a result, grazing activities are predominant. It is assumed that Cu and Zn are often used as additives for animal feed and enter animal wastes through incomplete absorption, and thus, the application of animal wastes in agriculture causes pollution with Zn and Cu. Pollution load index revealed that 42% of the study sites were polluted and 58% remained unpolluted. Principal component analysis and enrichment factors show that anthropogenic activities are responsible for the current pollution, where Zn and Cu predominate. The wetland sites are being polluted at a minor level. The main reasons for the higher level of metal pollution in Balai wetland might be its geomorphic nature and even anthropogenic activities. This wetland is located at the junction point of the Surma-Kushiyara River in Bangladesh, where an international river, Barak, intersects there, which originated from the upper territory. It is urgent to formulate an integrated action plan to prevent the source points of pollution. [ABSTRACT FROM AUTHOR]

This paper aims to measure the metals (Fe, Cu, Cr, Co, As, Zn, Hg, and Pb) concentration and assesses human health risks posed by these eight metals in the five most available cultured fish species (Pangasiuspangasius, Oreochromisniloticus, Heteropneustesfossilis, Anabustestudineus, Clariasbatrachus) collected from the Mymenshing Sadar Upazila. Both fishes and three fish feeds were analyzed using energy dispersive X-ray fluorescence (EDXRF). In fish feeds, the concentrations of metals were detected in the following order Fe > Zn > Cu > Hg > Pb. Besides, Hg concentration in three feeds samples was found higher than the maximum residue limit. Fe, Cu, Cr, Co, As, Zn, Hg, and Pb concentration in fishes were 82.45 to 104.55, 24.47 to 32.88, 2.62 to 6.73, < 0.28, < 0.41, 70.01 to 96.56, 0.57 to 1.07, and 0.34 to 0.49 µg/g respectively as dry weight basis. Health Risk Index (HRI) was observed > 1 both for adults and children and maximum HRI values for Pb was found in both P. pangasius and C. batrachus fish species. Additionally, PCA explained 73% variation in data and CA comprised the similarity within sampling stations. Pearson correlation implied a strong association amongst the trace metals. Finally, the accumulation of metals tends to the massive health hazard that should be mitigated by adopting several measures on fish feeds. [ABSTRACT FROM AUTHOR]

This study has evaluated the potential ecological risk and human health risk for the contamination of nine elements (Cu, Cr, Mn, Zn, As, Pb, Co, Fe, and Sr) in water and sediment samples in two seasons, i.e., before and after rainy season, by calculating several pollution indices such as pollution load index (PLI), potential ecological risk (PER), and target hazard quotient (THQ). Samples were analyzed for elemental concentration using energy dispersive X-ray fluorescence (EDXRF) spectrometry. This study found that waters in the Kutubdia channel are safe and standard for aquatic organisms. In addition, the study area's elemental concentration in water and sediments is still safe but moderately enriched with Zn and Cu. The elemental concentration in water was observed to be high in the pre-monsoon season and vice versa in the sediment study. The result also reveals no potential ecological risk (PER < 4) in the study site. However, the health risk index showed a noncarcinogenic risk (THQ > 1) for children and adults regarding the inhalation process where manganese was dominant. Apart from this, the pollution source was also identified by multivariate statistical analysis, including cluster analysis (CA) and principal component analysis (PCA)--and a natural pollution source prevalent was found. [ABSTRACT FROM AUTHOR]

In industrial areas, increased human activities generate high emissions of metals that contaminate the environment, and eventually affect human health. Therefore, this study aims to investigate the sources of toxic elements in indoor dust samples, and to evaluate possible health risks due to expose of human body through dermal contact, inhalation, and ingestion. A total 36 indoor dust samples were collected from the windows of twelve (12) industrial buildings, which are facing the main roads in the biggest export process zone (DEPZ) in Dhaka City, Bangladesh. The indoor dust samples were analyzed using X-ray fluorescence (XRF) technique for the determination of Cu, Zn, As, Pb, Fe, Cr, Co, Ni, K, Ca, Ti, Rb, and Sr. This investigation revealed that Cu, Zn, Pb, Fe, and Sr concentrations were slightly higher in various degree than that of the background value in soil recommended by the Chinese Environmental Protection Administration (CEPA). Subsequently, ANOVA (α = 0.05, p < 0.001) test and %RSD values (33% to 168%) showed that the concentrations of these metals were present non-homogeneously in different sampling points. However, statistical analysis and several geochemical indices have been proposed that these heavy metals might be come in indoor dust samples because of anthropogenic events. This investigation also showed that the most-extreme permissible hazard index (HIs) levels known as non-cancer risk for As, Mn, and Zn because of dust exposure in the study area were below than that of the safe limit (HI = 1) but with an exception of Pb (HI = 1.9E+00) for children. On the other hand, the degree of cancer-causing risk linked with exposure to arsenic in indoor dust (i.e., 0.502E-06 to 0.121E-05) falls within the range of threshold values (10−6 to 10−4). Therefore, following USEPA health risk models, it has been suggested that these metals present in indoor dust samples might not have significant impact on causing non-cancer and cancer risk to children and to adult at this moment in the DEPZ area, Bangladesh. However, a continuous monitoring should be needed to assess more accurately the non-cancer and cancer risk to children and adult. [ABSTRACT FROM AUTHOR]

Trace metals concentration and proximate composition of raw and boiled silver pomfret (Pampus argenteus) from coastal area and retail market were determined to gain the knowledge of the risk and benefits associated with indiscriminate consumption of marine fishes. The effects of cooking (boiling) on trace metal and proximate composition of silver pomfret fish were also investigated. Trace element results were determined by the Energy Dispersive X-ray Fluorescence (EDXRF) Spectrometer wherein fish samples from both areas exceeded the standard limits set by FAO/WHO for manganese, lead, cadmiumm and chromium and boiling has no significant effects on these three metal concentrations. Long-term intake of these contaminated fish samples can pose a health risk to humans who consume them. [ABSTRACT FROM AUTHOR]