Search

Indexical appraisal of potentially toxic elements (PTEs) in sediment and fish of riverine ecosystem give valuable information for environmental management. In this research, PTEs were measured in s...

Particle-induced X-ray emission (PIXE) method was used in this present research to identify the elements present in selected vegetable samples to show the possible influence in the metal absorption by the vegetables grown in a saline region of Rampal area of Munshiganj District, Bangladesh. The data acquisition setup is calibrated using a 2.5-MeV proton beam in the current ranges of 5nA to 15nA. The detector was used to measure the X-rays emitted during the irradiation. Data acquisition system MAESTRO-32 was used to measure the spectrum picks, and concentration calculation has been done by GUPIX/DAN-32 software. The purpose of this study is to determine the concentration of heavy and trace elements in these samples and to give current information on their safety for consumption. The result shows that K, Ca, and Fe have the highest concentrations, while lead exhibits the lowest but alarming rates compared to reference materials. The findings were likened to IAEA-V-10, IAEA-359, SRM 1515 (apple leaf), and SRM 1573a (tomato leaf). The outcomes of the present investigation demonstrate that these samples are not devoid of health risks in intake.

To assess the magnitude of water quality decline in the Turag River of Bangladesh, this study examined the seasonal variation of physicochemical parameters of water, identified potential pollution sources, and clustered the monitoring months with similar characteristics. Water samples were collected in four distinct seasons to evaluate temperature, pH, dissolved oxygen (DO) concentration, five-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), electrical conductivity (EC), chloride ion (Cl−) concentration, total alkalinity (TA), turbidity, total dissolved solids (TDS) concentration, total suspended solids (TSS) concentration, and total hardness (TH) using standard methods. The analytical results revealed that 40% of water quality indices were within the permissible limits suggested by different agencies, with the exception of EC, Cl− concentration, TA, turbidity, DO concentration, BOD5, and COD in all seasons. Statistical analyses indicated that 52% of the contrasts were significantly different at a 95% confidence interval. The factor analysis presented the best fit among the parameters, with four factors explaining 94.29% of the total variance. TDS, BOD5, COD, EC, turbidity, DO, and Cl− were mainly responsible for pollution loading and were caused by the significant amount of industrial discharge and toxicological compounds. The cluster analysis showed the seasonal change in surface water quality, which is usually an indicator of pollution from rainfall or other sources. However, the values of different physicochemical properties varied with seasons, and the highest values of pollutants were recorded in the winter. With the change in seasonal temperature and increase in rainfall, the seasonal Turag River water followed a self-refining trend as follows: rainy season > pre-winter > summer > winter.

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, surfac...

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, 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.

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.

The increasing industrial activities, number of vehicles on road and population in large cities causes the contamination of air in urban environment, and eventually affect human health. Therefore, the aim of this study was to collect soil and dust samples from twelve roadside academic institutions in Dhaka City, Bangladesh. One of the twelve sites is control site for this study. The elemental (Ca, Fe, K, Ti, Sr, Zn, Zr, Rb, Cr, Ni, Pb and Cu) concentration in soil and dust samples were analyzed by XRF technique. The metals concentration in dust and soil samples followed the following order: Fe > Ti > Sr > Zn > Zr > Rb > Pb > Cu, and Fe > Ti > Zr > Sr > Rb > Zn > Cu > Pb > As, respectively. As expected, the most elemental concentration at the control site, which was situated inside a village and ~ 1 km far away from the road, was lower compared with those in soil and dust samples. Average As concentration (16.52 mg/kg) in soil was observed to be three times higher than its background value. The concentration of Pb in the dust sample of a school at Sadarghat (136.04 mg/kg) was significantly higher than the other sites. We observed that the mean concentration for most of the metals had a higher concentration than the background values set by Chinese Environmental Protection Administration (CEPA), except for K and Zr. Soil samples were analyzed to determine the percentage of organic matter by dry combustion technique, and the average amount of organic matter in soil samples was 1.42%. Conversely, the contamination levels of heavy metals were assessed based on the geo-accumulation index (Igeo), enrichment factor (EF) and contamination factor (CF). Subsequently non-carcinogenic health risk was determined using lifetime average daily dose (LADD). The non-carcinogenic health risk was found to be more prominent for children than that for adults. No significant carcinogenic health risk was found in the study area.

Trace metals contamination is ubiquitous in the riverine environments of Bangladesh. Trace metals contamination is increasing rapidly in Dhaleshwari River due to rapid urbanization and industrialization along the riverbank, especially after the establishment of the Tannery Industrial Estate at Savar in Dhaka District. As a result, aquatic ecosystems, including fish and prawn species of the river, are contaminated by various trace and toxic metals. We examined the concentrations of 10 trace metals (Cr, Fe, Zn, Mn, Co, Ni, Cu, As, Hg, and Pb) in 20 different fish and prawn species (n = 41) which are commonly found in the Dhaleshwari River using energy-dispersive X-ray fluorescence (EDXRF) method. The potential human health risks (noncarcinogenic and carcinogenic) of the trace metals were calculated by using Target Hazard Quotient (THQ), Hazard Index (HI), and Target Cancer Risk (TR) indices. The mean concentration (mg/kg; ww) of the trace metals in analyzed riverine fish and prawn species was in the order of Fe > Zn > Cu > Cr > Mn > Co > Hg > Ni > Pb > As. The highest concentration of Fe (74.67 mg/kg) and Cr (4.64 mg/kg) was found in Mystus bleekeri, whereas Zn (38.89 mg/kg) and Cu (17.47 mg/kg) were found in Rohtee cotio and Glossogobius guiris, respectively. The target hazard quotient (THQ) values were less than 1 (no detrimental health effects) for all the specific metals in most of the species except M. bleekeri (1.61), G. guiris (1.29), Corica soborna (1.28) for Cr, and Macrobrachium malcolmsonii (1.19) for Hg indicate that the noncarcinogenic health risk to humans by consuming those species was relatively low. However, nine out of twenty species found higher Hazard Index (HI) values than the recommended value (HI = 1), indicating that regular consumption of these fishes may have considerable harmful effects on human health. The highest HI value (2.85) was found in M. bleekeri. Moreover, target cancer risk (TR) values showed that frequent intake of some species for prolonged periods might pose a carcinogenic risk due to Cr and Ni contamination as they were higher than the maximum accepted value of 10−4. Based on the present study, it is imperative to take an urgent initiative to control or prevent the trace metals contamination in the Dhaleshwari River and minimize the human health risks associated with the consumption of fish and prawn species in this river in Bangladesh.

Soil samples were collected from ten sampling points surrounded the Rooppur Nuclear Power Plant to determine the metal concentration like As, Pb, Rb, Sr, Zr, Cu, and Zn. The metals concentrations in soil samples were determined by the Energy Dispersive X-ray Fluorescence (EDXRF) technique. The average metal concentrations in the study area were found in the following descending order: Zr (334.84 mg/kg) > Rb (179.35 mg/kg) > Pb (172.77 mg/kg) > Sr (138.86 mg/kg) > Zn (120.54 mg/kg) > Cu (16.96 mg/kg) > As (8.50 mg/kg) respectively. Moreover, the sampling sites were organized according to the total metal concentration as S7 > S3 > S4 > S5 > S11 > S2 > S9 > S1 > S10 > S8 > S12 > S6 respectively. This study showed that the average concentration of As, Sr, and Cu surpassed the suggested standard and average shale value (ASV) limits. In this study, the identification of the soil quality associated with the ecological and human health risk was evaluated using some important indices. The geoaccumulation index (Igeo) deliberated that most of the sites were not contaminated except for S3 and S7, which were classified as strong contamination and strong to extreme contamination. The enrichment factor (EF) revealed that three sampling points of S3, S4, and S7 were enriched with Pb, which was consistent with the contamination factor (CF) suggested that the study area was contaminated by only Pb and Zn. It might happen due to excess battery rechargeable vehicles in the study area. However, this study revealed that the pollution load index (PLI) for most of the sampling points was lower than 1 (PLI

Although coastal water marine algae have been popularly used by others as indicators of heavy metal pollution, data within the Bay of Bengal for the estuarine Cox’s Bazar region and Saint Martin’s Island has remained scarce. Using marine algae, the study herein forms an effort in biomonitoring of metal contamination in the aforementioned Bangladesh areas. A total of 10 seaweed species were collected, including edible varieties, analyzed for metal levels through the use of the technique of EDXRF. From greatest to least, measured mean metal concentrations in descending order have been found to be K > Fe > Zr > Br > Sr > Zn > Mn > Rb > Cu > As > Pb > Cr > Co. Potential toxic heavy metals such as Pb, As, and Cr appear at lower concentration values compared to that found for essential mineral elements. However, the presence of Pb in Sargassum oligocystum species has been observed to exceed the maximum international guidance level. Given that some of the algae species are cultivated for human consumption, the non-carcinogenic and carcinogenic indices were calculated, shown to be slightly lower than the maxima recommended by the international organizations. Overall, the present results are consistent with literature data suggesting that heavy metal macroalgae biomonitoring may be species-specific. To the best of our knowledge, this study represents the first comprehensive macroalgae biomonitoring study of metal contamination from the coastal waters of Cox’s Bazar and beyond.

Particle-induced X-ray emission (PIXE) method was used in this present research to identify the elements present in selected vegetable samples to show the possible influence in the metal absorption by the vegetables grown in a saline region of Rampal area of Munshiganj District, Bangladesh. The data acquisition setup is calibrated using a 2.5-MeV proton beam in the current ranges of 5nA to 15nA. The detector was used to measure the X-rays emitted during the irradiation. Data acquisition system MAESTRO-32 was used to measure the spectrum picks, and concentration calculation has been done by GUPIX/DAN-32 software. The purpose of this study is to determine the concentration of heavy and trace elements in these samples and to give current information on their safety for consumption. The result shows that K, Ca, and Fe have the highest concentrations, while lead exhibits the lowest but alarming rates compared to reference materials. The findings were likened to IAEA-V-10, IAEA-359, SRM 1515 (apple leaf), and SRM 1573a (tomato leaf). The outcomes of the present investigation demonstrate that these samples are not devoid of health risks in intake.

The mean concentrations of heavy metals viz: K, Ca, Mg, Ti, Fe, Co, Cu, As, Zn, Rb, Sr, Zr, Pb and Th were measured in soil samples using Energy Dispersive X-ray Fluorescence (EDXRF) technique and sampling sites as a whole were found highly contaminated by Zn, considerably contaminated by Mg and Pb, while moderately contaminated by Fe, Co, Cu, Rb, Sr, As, Rb, Y, Th. The sampling sites are moderate to strongly polluted by heavy metals according to Enrichment factors value, whereas, Pollution Load Index values for 95% of the sample sites were ≥ 1.5, indicating deterioration of soil quality. Potential Ecological risk (RI) value followed the increasing sequence of Pb > As > Co > Zn > Cu. Non-carcinogenic exposure found higher in children compared to adults,however carcinogenic risk assessment revealed that both groups (adult and children) lied within Grade II category (10− 5 to 10− 6) and considered to be at no risk.

Contaminants in road dusts can directly pose significant human health risks through oral ingestion, particle inhalation, and dermal contact. Therefore, this study has been designed to analyze heavy metal contaminations in 88 street dusts collected from the 22 high traffic sites and industrial areas of the Southeast Asian Megacity: Dhaka (capital of Bangladesh) using energy dispersive X-ray fluorescence (EDXRF) spectroscopy. This study revealed that the maximum Pb, Cd, Zn, Cr, Ni, As, Mn and Cu contents in the street dust samples were 18.9, 11.6, 239.2, 144.3, 37.1, 8.1, 261.5 and 49.6 mg/ kg respectively in which Ni and Pb concentration were 2 times, and Cd concentration was 200 times higher than the background level in soil; and As concentration was slightly higher than soil background level. The spatial distribution of heavy metal concentrations in street dust samples in Dhaka City was revealed that the hot spot areas of Pb, Ni, Cd and As were mainly associated with heavy traffic and industrial activities. The risk assessment strategies were used for this study for identifying the routes of exposure through oral ingestion, inhalation, and dermal contact by the fine particles (~75 μm) of street dust, especially for children based on the US EPA health risk models. Both non-carcinogenic and carcinogenic risks of heavy metals were characterized in street dust samples. Results based on the hazard index (HI), in the case of non-cancer effect, the ingestion of dust particles of children and adults in Dhaka City appeared to be the route of exposure to street dust that results in a higher risk for heavy metals, followed by dermal contact. This study revealed that the inhalation of re-suspended particles through mouth and nose were almost negligible. It was also noticed that children were experiencing the potential health risk due to HI for Cr (1.04), which was slightly higher than the safe level 1, and Cd (0.69) was close to the safe level 1. Reversely, cancer risk for Cr (i.e. 4.27 × 10−6) was fallen within the range of threshold values (10−4 to 10−6) and As (i.e. 9.59 × 10−7) was close to the upper limit of threshold values (10−4 to 10−6).

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.

The focus of this study was to determine the depth-wise variability of physicochemical properties (i.e., pH, TOC, TN, and EC), and heavy metals (i.e., Pb, Cu, Zn, As, and Cr) concentration, and the associated biological and ecological risks of the mangrove sediment. The accumulation of metal contents and the phytoremediation and phytoextraction were also investigated in a mangrove species, Acanthus ilicifolius. The mangrove sediment consists of a higher proportion of sand fraction (56.6–74.7%) followed by clay (10–28%) and silt (10.1–15. 7%) fractions. The concentrations (mg/kg) of Pb, Cu, Zn, As, and Cr were ranged from 22.05–34.3, 8.58–22.77, 85.07–114, 5.56–12.91, and 0.98–5.12 in all the sediment layers. The hierarchy of the mean metal concentration in sediment was Zn (102 mg/kg) > Pb (25.6 mg/kg) > Cu (14.8 mg/kg) > As (8.79 mg/kg) > Cr (2.74 mg/kg) respectively. The examined metal concentrations were below the respective average shale values (ASVs). The degree of environmental, ecological, and biological risks was minimal according to various pollution indices like geoaccumulation index (Igeo), contamination factor (CF), and pollution load index (PLI). According to sediment quality guidelines (SQGs), the adverse biological risk effect was not likely to occur. The result of the potential ecological risk index (PERI) demonstrated that the study area was in the low-risk condition as the corresponded RI value Pb (28. 7) > Cu (16.9) > As (11.2) > Cr (4.99) in leaves and Zn (104.32) > Pb (27.02) > Cu (15.29) > As (10.39) > Cr (3.80) in roots. The translocation and bioaccumulation factors of heavy metals suggested that the mangrove plant species, A. ilicifolius can be used for phytoremediation and phytoextraction since the bio-concentration factor and translocation factor > 1. The studied species exhibited the metal tolerance associated with two following strategies, metal exclusion, and metal accumulation. However, excess metal tolerance can impact the surrounding marine environment.

Assessment of elemental contamination is emerging research in the present world. Metals are hazardous to the environment and people's health when metals concentration might exceed the tolerable level. In this research, 12 elements (i.e., Mn, Ni, Cu, Zn, As, Se, Sr, Co, Pb, Fe, Rb, and Ti) were assessed using the energy dispersive X-ray fluorescence (EDXRF) method in water and sediment samples in four (4) different spawning grounds of Tenualosha ilisha at the confluence of the Meghna River in Bangladesh. A comparative analysis was performed for the first time among four sampling spots, i.e., Chandpur, Bhola, Sandwip, and Hatiya, assessed all possible risk indices-it is a unique thing. Several risk indices were solved to determine the degree of sediment pollution for all 12 elements, e.g., degree of contamination (Cd):6.5–7.01, the modified degree of contamination (mCd): approximately 0.7, the pollution load index (PLI): 0.45–0.51, etc. where all the indices' results showed low or baseline levels of pollution. According to the enrichment factor (EF) computation, slight enrichment of examined metals except Pb and Zn was found. In addition to these, the ecological risk factor (Er) found in the following order (pollution level: low): Cu > Pb > Zn among the four stations. Moreover, a spatial incline of metal accumulation was observed among the four spots: Bhola < Sandwip < Hatiya < Chandpur based on the risk index (RI) set value. However, a strong positive correlation (p < 0.05) between Ca and Fe, Ti and Fe, Ti and Mn, Mn and Fe, Fe and Sr were observed while Ca, and Co were strongly negatively correlated (r = minus (-)0.60, p < 0.05). The cluster analysis was performed and got an asymmetrical cluster among the sampling stations. This study recommends assessing the heavy metal concentration in biological samples, particularly in Hilsha fish., Trace metal; Contamination factor; Spawning ground; River Shad; Risk index.

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 &lt, 4) in the study site. However, the health risk index showed a noncarcinogenic risk (THQ &gt, 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.

This study was carried out to characterize the biogeochemical and physicochemical properties of landfill leachate from Matuail Sanitary landfill site, Dhaka, Bangladesh. In addition, the study also aimed to identify the photodegradation of landfill leachate under natural sunlight. The leachate pH was slightly alkaline (7.87–8.07) with a minimum level of dissolved oxygen, and low BOD5/COD ratio that are indicators of the matured methanogenic phase. Ca, Fe, Br, Rb, Cu was present in a considerable amount. A trace amount of Sr, Co, As, Pb, Cr was found in the leachate sample. Fourier Transform - infrared (FTIR) spectra of all three samples had five major peak regions notably at 3440–3450 cm−1 (O–H groups of water), 1638 cm−1 (C=O Amide I, carboxylates C=C, aromatic ring modes, or alkenes), 1385–1390 cm−1 (deformation of the C–H bond in CH2 and CH3, or the asymmetric stretching of COO¯), 1115 cm−1 (stretching of the C–O bond in phenol ethers and phenols) and 605 cm−1 (S–O bends of sulfates). In addition to the appearance of new peak, peak shifting on the 2nd-day and 5th-day phototreatment are in compliance with the 34% TOC reduction. From analyzing three-dimensional excitation/emission (3D-EEM) spectra of the raw sample pyrene-like or humic-like peak A (Ex 255/Em 465), soil fulvic-like peak Mp (Ex 315/Em 450), and humic-like peak C (Ex 370/Em 455) was found indicating more humified characteristics of the mature landfill site. From 1-hour to 6-hours phototreatment, all three substances slightly lost fluorescence intensity. From the 2nd day to the 5th day of photo-treatment, two unknown photo-product was identified within Ex 210/Em 457 and Ex 205/Em 408 at peak A region. Fluorescence intensity lost was 65% for peak A and 44% for peak C. Soil fulvic-like peak Mp was absent on the 5th day of photo-treatment., Fluorescence dissolved organic matter (FDOM); Elemental concentration; Landfill leachate; Matuail landfill; Photodegradation; X-Ray fluorescence (XRF).

An assessment of the dietary risk of heavy metal exposure to humans is important since it is the main source of exposure. This study aimed to estimate the degree of contamination and assess the probable health risk in the prawn food chain. In prawn feed, the concentrations of metals were detected in the following order: Hg > Co > Pb > Cd. The concentrations of heavy metals in prawn were the highest for Co and lowest for Cd. Trace amounts of As and Cr were detected in the analyzed sample. Target hazard quotients for heavy metals for adults were >1 for Pb, Cd, Hg, and Co, and for children, the same were high for Co and Hg, indicating significant health risks upon dietary exposure. All the prawn samples contained nine-fold and fourteen-fold higher concentrations than the maximum acceptable levels for Pb and Hg, respectively (0.5 mg kg −1 ; WHO/FAO). Human health risk due to the Co exposure is quite alarming as the level of exposure was found to be very high. In the prawn samples intended for human consumption, the hazard index (HI) was highest in the samples obtained from Bagerhat (3.25 in flesh and 3.26 in skin), followed by the samples obtained from Satkhira (2.84 in flesh and 3.10 in skin) and Dhaka City Corporation (2.81 in flesh and 3.42 in Skin); this indicates a potential risk of prawn consumption obtained from Southeast Bangladesh. This is particularly problematic as this area accounts for the majority of prawn production and export of the country.

Samples for sediment and two species of native mangrove plants were collected from seven sampling sites for assessing the level of metal contamination. Results of the studied metals displayed the order of pollution as Fe > Ti > Zr > Rb > Zn > Sr > Pb > Y > Cu > Cr > As accordingly. Geoaccumulation index and contamination factor revealed that the sediment samples were unpolluted to moderately polluted by Zn, Fe, Ti, Rb, Y, and Zr. Ecological risk factor depicted a pollution-free condition in the study areas. PCA, CA, and correlation coefficient indicated that the source of the metals in the environment was anthropogenic. Bioconcentration factor values were found to be below 1 in both plant species. Conversely, transfer factor values for most heavy metals were found to be >1 in both plant species, which reflects the phytoremediation ability of plants.

Nowadays developing countries around the globe have been undergoing rapid industrialization which is eventually responsible for environmental contamination. For proper assessment of the level of pollution and the proper application of remediation measures, it is imperative to know the pristine geochemistry of the system. In that regard, environmental-geochemistry of a southern part (Rampal: potential site of rapid industrialization) of Bangladesh, has been investigated for elemental abundances, natural radioactivity and physicochemical records of environmental compartments (soil, sediments, river-water). Nuclear analytical techniques such as instrumental neutron activation analysis, energy dispersive X-ray fluorescence, gamma spectrometry were used for soil sample study whereas atomic absorption spectroscopy, UV–vis spectrophotometer etc. were used for water sample analysis. Twenty six elemental abundances (Na, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Ga, As, Rb, Sr, Y, Zr, Sb, Cs, Ba, Hf, Ta, W, Pb) including three naturally occurring radionuclides (226Ra, 232Th, 40K) in soil samples and six elemental concentrations (Cu, Zn, Fe, Mn, Cd, Pb), four anionic concentrations ( N O 3 - , S O 4 - 2 , P O 4 - 3 , C l - ) and four physicochemical parameters (total-alkalinity, total-hardness, electrical-conductivity, pH) of river water were investigated in this study. Along with the experimental data, statistical analysis, several environmental indices (geo-accumulation index, enrichment factor, pollution load index, Potential ecological risk index) and radiological health related indices (radium equivalent activity, radiation hazard index, absorbed dose rate, annual effective dose rate) have been identified for comprehensive assessment of our study site. This study reveals that Rampal receives trivial anthropogenic impact and possesses insignificant ecological and radiological health hazards.

The concentrations of Cr, Cd, Pb, Hg, and As in water, poultry meat, fish, vegetables, and rice plants obtained from the area adjacent to the Hazaribag tannery campus, Dhaka, Bangladesh, were estimated and compared with permissible levels established by the WHO and FAO and levels reported previously by other authors. The metal contents were in the following order according to the concentration in contaminated irrigation water: Cr > Pb > As > Hg > Cd. Mean concentrations of Cr, Pb, Hg, and As in irrigated water were above the permissible levels, whereas the results were below the permissible levels for Cd. The metal concentrations in poultry meat, fish, rice, and vegetables were in the following orders: Pb > Cr > Cd > Hg > As, Pb > Cr > Cd > As > Hg, Pb > As, and Cr > Pb > Cd > As > Hg, respectively. The mean concentrations of metals in poultry meat, fish, rice, and vegetables were much higher than the permissible levels. The trends of weekly intake of heavy metals (WIMs) from poultry meat, fish, rice, and vegetables were as follows: Pb > Cr > Cd > Hg > As, Pb > Cr > Cd > As > Hg, Pb > As, and Cr > Pb > Cd > As > Hg, respectively. WIMs for all the metals were lower than the provisional maximum weekly intake recommended by WHO/FAO and USNAS.

• Chemical pollution in marine ecosystems is leading towards an increase in the concentrations of heavy metals in fish body, which might have a negative impact on human health through consumption of fish. Here, five commercially important marine fishes (i.e. Sillaginopsis panijus, Trichiurus lepturus, Harpadon nehereus, Rita rita and Coilia dussumieri) were collected from the Kutubdia Channel of the northern Bay of Bengal, Bangladesh. Samples were collected during pre-monsoon and post-monsoon for the year of 2016 to measure the heavy metal concentrations in edible part (flesh) of the fishes; and finally to assess the human health risk due to consumption of those fishes. Heavy metal concentrations (i.e. Cr, Cu, Pb, Mn, Sn and As) in the collected fish species were determined using energy dispersive X-ray fluorescence (EDXRF) method. Subsequently, for assessing the human health risk, the target hazard quotient (THQ) values were estimated. This study found that the heavy metal concentration for Cr, Cu, Pb, Mn, Sn and As in fish samples were 1.51 to 2.53, 2.14 to 5.08, 2.89 to 3.41, 14.54 to 18.45, 23.04 to 32.21 and

A background study of the chemical constituents of some environmental samples - tannery complex sand, river water, river sediment and river fishes collected from the Relocated Hazaribagh Tannery Complex (RHTC) area, was carried out. In sand samples the mean values for pH, EC and soluble salts were found to be 8.49, 0.02 mS/cm and 11.72 mg/kg and the mean concentrations of elements K, Ca, Ti, Mn, Fe, Co, Zn, As, Pb, Rb and Sr were 94.8, 68.5, 16.6, 2.68, 129, 1.19, 0.23, 0.70, 0.32, 0.62 and 1.03 mg/kg, respectively. In river water samples the average concentrations of K, Ca, Mn, Fe, Zn, As, Rb, Sr, SO 4 -2 , PO 4 -3 , Cl -1 and NO 3 -1 were 13.09, 178, 0.41, 1.82, 0.073, 0.031, 0.010, 0.48, 0.057, 0.019, 15.6, 5.68 mg/l and the average values for pH, EC, DO, BOD, SS and DS were 8.02 and 0.35 mS/cm, 6.29, 4.21, 0.06, 0.36 mg/l, respectively. The elements K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Rb, Sr and Pb were measured in river sediment samples at the limit of 205, 155, 67, 6.02, 17.2, 798, 1.10, 1.24, 1.99, 0.31, 2.34, 2.63 and 0.35 mg/kg, respectively. In some locally available fishes like tengra, puti, baim, taki, shrimp, chanda and baila, only the elements K, Ca, Fe, Zn, Rb and Sr could be measured in all species of fishes in the range of 0.39 - 1.01, 0.68 - 2.29, 60.6 - 125, 46.3 - 174, 2.84 - 61.8 and 12.3 - 38.0% in mg/kg, respectively. In the light of the overall study, the chemical constituent levels of the environmental samples of the RHTC area at present are low and the environment is not yet contaminated. DOI: http://dx.doi.org/10.3329/jbas.v36i1.10919 Journal of Bangladesh Academy of Sciences, Vol. 36, No. 1, 45-51, 2012

Current research has been focused on the transfer of heavy metals (Fe, Pb, Co, Cd, V, Cu, Mo, Ni, Cr , Mn, Zn, As, Sr, Hg,) and radionuclides ( 40 K, 232 Th, 226 Ra, 238 U and 137 Cs) from soil to vegetables and plants in terms of transfer factor which is commonly used to estimate the food chain transfer of these elements and possible phytoremediation. Wide varieties of vegetables and plants and associated soils were collected from various regions of Bangladesh under actual field conditions. Contamination levels of the elements was measured and the Health Risk Index (HRI) and Plant Transfer Factor (PTF) of these elements from soil to vegetable/plant were calculated. Results reveal that there is a substantial build up of heavy metals (Mo, Sr, Fe, Cd, V, Cu, Ni, Cr , Mn, Zn , As) pollution in the soil of Bangladesh which varies with location depending on the sources. In addition, heavy metal (Fe, Sr, Ni, Zn, Cr, Mn, Pb, Cd ) content in plants grown near the industrial area showed higher values than in the non-polluted area and also exceeded the world average soil data. The HRI for heavy metals in the plants showed the order Mn > Fe > Cr > Pb > Zn > Cd > As where unsafe HRI values were found for Fe, Pb and Zn in Abelmoscus escultant and leafy vegetables indicated health risks associated with the ingestion of these contaminated vegetables to the inhabitants. The PTF value for heavy metals varied greatly with plant species and also with sampling location. A higher PTF value (0.4–4.5) was found for Mn, Zn, Cu in Enhydra fluctuans , Zea mays , Nephrolepis exaltata and Oryza sativa which could be used for phytoremediation of these metals from the contaminated soil. Conversely, the TF of the radionuclides were found in the following order: 40 K > 232 Th > 226 Ra > 238 U whereas 137 Cs was not transferred. The higher TF found in the study for all the natural radionuclides indicates that the area is a high background radiation area (HBRA) and radiologically unsafe to the inhabitants due to the harmful effects of ionizing radiation from natural radionuclides in soil.

The effect of latex maturation on the physicochemica1 properties of radiation vulcanized natural rubber latex films was studied. The properties were compared to those of the nonirradiated natural rubber latex films at the same condition. For this purpose, field and concentrated latices were used. Tensile strength, modulus, tear strength, gel content, and cross-link density for both the nonirradiated and irradiated latex films increase with the increased length of maturation time, and these properties possess maximum values at nine weeks maturation period, whereas the elongation at break decreases to a minimum at the same length of maturation time.

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.

Background Unsafe food consumption is a severe problem because of heavy metal contamination, which is caused by director indirect activities of industries. The present study was conducted to assess the risk of human health by Heavy metals (Cu, Co, Fe, Zn and Mn) through the intake of vegetables and fishes obtained from the area adjacent to the Hazaribag tannery campus, Dhaka, Bangladesh. Result The trend of mean metal concentration in Buriganga river water was Fe >Mn > Zn > Cu > Co and according to Department of Environment, Dhaka Bangladesh (DoE) (1999) the value of the above metals are within the permissible limit of irrigation water except Fe. An assessment of risk involved due to consumption of contaminated food also calculated. The trend of metals in vegetables was Fe > Mn > Zn > Cu > Co and in fishes the trend was Fe > Zn >Mn > Co > Cu. Accumulation of trace elements in vegetables was lower than maximum tolerable levels proposed by FAO/WHO food standard programme (2001) with the exception of Fe and Co respectively. In fishes metal concentration was lower than safe limit set by WHO (1989) except Mn. The Metal Pollution Index (MPI) for all the foodstuffs showed a higher value, however the calculated Health Risk Index (HRI) indicated no risk to human health upon consumption of those foodstuffs. Conclusion The overall study suggests that foodstuff in the area were contaminated by the assayed metals and long-term consumption can cause potential health risks to consumers.

Metal contamination in agricultural soils is of increasing concern due to food safety issues and potential health risks. Accumulation of Heavy and trace metals in vegetables occur by various sources but soil is considered the major one. Consumption of vegetables containing (heavy/trace) metals is one of the main ways in which these elements enter the human body. Once entered, heavy metals are deposited in bone and fat tissues, overlapping noble minerals and cause an array of diseases. The present study aimed to investigate the concentration of different metals in agricultural soil and vegetables grown on those soils and to evaluate the possible health risks to human body through food chain transfer. Contamination levels in soils and vegetables with metals were measured and transfer factors (TF) from soil to vegetables and its health risk were calculated accordingly. Results showed that concentration of Si, Ba, K, Ca, Mg Fe, Sc, V, Cr, Cu, Zn, As, Mn, Co, Ni, Se, Sr, Mo, and Cd in soil is higher than the World Average value and Al, Ti and Pb is lower than the World Average value whereas concentration of toxic elements like As, Co, Cu, Mn, Pb, Se, Ni, V and Zn in vegetable samples are below the World Average value. The intake of toxic metals (Fe, Cu, Mn, Zn Co, Cr, V, Ni, Pb and Cd) from vegetables is not high and within the permissible limit recommended by WHO, Food & Nutritional Board and US EPA. The Hazard Quotient (HQ) for Fe, Cu, Co, Cr, V, Ni, Pb, Mn, Zn and Cd were calculated which showed a decreasing order of Cd>Mn>Zn>Pb>Cu>Fe>Ni>V=Co>Cr. Highest HQ value found for Cd (2.543) which is above the safe value. Electronic supplementary material The online version of this article (doi:10.1186/2193-1801-2-385) contains supplementary material, which is available to authorized users.

This paper reviews the present state of nuclear power infrastructure of Bangladesh. It describes how Bangladesh is progressing towards nuclear power. The major infrastructure issues about the way in which to implement the country’s first nuclear power project have been identified and analysed. The domestic education and training infrastructure of the nuclear power sector of the country has been reviewed and it is regarded as the most critical challenge to commence the nuclear power programme in the country. A broad-based academic and research capability in nuclear science and engineering disciplines and the professional educational and training courses for different tiers of professionals and staff of the Nuclear Power Plant (NPP) operating organisation and nuclear regulatory authority needs to be strengthened for the sustainable development of the nuclear power sector as well as the economic operation of nuclear power facilities of the country. An approach to the manpower development for the national nuclear power sector has also been proposed.

A study was carried out to characterize dye industry effluent by measuring its various physicochemical characteristics and trace heavy metals and to asses its quality to be used as an alternate means of irrigation. As a case study the results obtained from the investigation of effluent of the Bangladesh Dyeing and Finishing Industries Ltd., Karnapara, Savar are reported in this study. The direct effluent (untreated effluent) and after it was treated in the laboratory (treated effluent) were investigated. As groundwater is a part of the effluent, it was also analysed. The average pH values of the untreated and treated effluents were found to be 7.83 and 5.13, respectively. The EC values of the untreated effluent (1.81mS cm-1) and treated effluent (2.01 mS cm-1) were found to be higher than that of groundwater (0.93 mS cm-1). No significant variation in pH and EC values of monthly collected effluent samples was observed. The average concentrations of trace elements except Fe were found to be lower than their DoE recommended values for irrigation land. The concentrations of Na and K in the untreated effluent were found to be higher and the Ca and Mg concentrations lower than those of the treated effluents. Assessment of the untreated and treated effluent was made based on their EC, the sodium adsorption ratio (SAR) and soluble sodium percent (SSP), COD and heavy trace metal contents. From the overall assessment, the treated effluent was found to be suitable for irrigation. DOI: 10.3329/jbas.v33i1.2954 Journal of Bangladesh Academy of Sciences, Vol. 33, No. 1, 99-106, 2009

The impact of various dilutions (2.5, 5, 10, 25 and 50%) of paint industry effluent on physico-chemical properties of soil and the germination, growth and dry matter productions of corn (Zea mays L.) and rice (Oryza sativa L.) have been studied. The effluent was acidic and had low BOD and COD values because of its low content of suspended solid. It contained high concentration of calcium, medium concentrations of nitrogen, sodium, potassium, sulphate, chloride and low concentrations of phosphorus, magnesium and bicarbonate. The trace element like Mn, Ni, Cu, Zn and Pb were measured in the μg L-1 level. On irrigation of soil with the effluent an increase in the water soluble salts, pH, electrical conductivity, cation exchange capacity, nitrogen, phosphorus potassium, sodium, calcium, magnesium and iron contents of the soil for effluent concentrations of 2.5, 5 and 10% were observed but all these parameters were found to decrease on treatment of the soil with the effluent concentration of 25% and above. The effluent of the lower concentrations (2.5, 5 and 10%) enhanced the growth of both crops. However, negative effects on seed germination, dry matter production and the yield of both crops were found for the effluent concentration of 25% and above. doi: 10.3329/jbas.v32i1.2441 Journal of Bangladesh Academy of Sciences, Vol. 32, No. 1, 41-53, 2008

The effect of coagulants on the preparation of dipped film with good physical properties was studied. In order to optimize various parameters like coagulant concentration, latex concentration, and former dipping time in latex and coagulant, the effect of coagulant on the physical properties of radiation vulcanized natural rubber latex film was evaluated. Calcium nitrate, calcium chloride, and ammonium nitrate were used as the coagulant by dissolving either in water or ethanol. Calcium nitrate solution was found to be the best one among the coagulants used.