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AbstractMicroplastics (MPs) possess a strong capacity to adsorb and biodegrade slowly, resulting in substantial harm to the environment and potential health risks. In recent years, a flourishing study of MPs has led to valuable advancements. This review article presents a comprehensive bibliometric analysis of global microplastic pollution, providing a deep understanding of published data, current progress, research trends, and focal points. We conducted extensive searches in the Scopus and Web of Science Core Collection databases from 2012 to 2021, utilizing the widely used R software for analysis. Our findings demonstrate a significant increase in micro(nano)plastic publications, with a growth rate of 73.0% from 2012 to 2021. China emerges as the predominant contributor in this field. The journal Science of the Total Environment has published the highest proportion of relevant articles (16.1%) and received the most citations (9801). The analysis further emphasizes polymer products and MPs as key research areas in the past decade. This study serves as a fundamental basis for future investigations into micro(nano)plastic pollution’s impacts on terrestrial and aquatic ecosystems. [ABSTRACT FROM AUTHOR]

In Dhaka megacity (Bangladesh), lakes located in the most exclusive areas are considered crucial urban water bodies. However, these water sources are confronting a heavy load of organic and inorganic pollutants by anthropogenic activities and are being polluted continuously. In this review , 50 relevant published documents on the lake water of Dhaka megacity to highlight the overall water quality status and the potential ecological and human health risks associated with contaminations were studied. The retrieved documents were organized according to the relevant information and examined thoroughly. After a careful review, it was found that most of the lake water in Dhaka city is severely contaminated with heavy metals such as Pb, Cd, Cu, Zn, and Mn with a higher concentration of Pb and Cd than the guideline values for drinking and industrial uses. The physicochemical properties and microbial contamination with an elevated level of fecal coliforms in lake water indicate very poor water quality in all lakes. The EC and TDS in most of the lake water exceeded the standard limits with the highest EC value (4920 µS/cm) for Gulshan Lake. The indices-based water quality assessment revealed considerable heavy metal contamination in the lake's water. Few lakes are found at a minimal level of ecological risks. The assessments of health risk indicate lower non-cancer risk. Overall, it can be inferred that the lake water in the Dhaka megacity does not meet the requirements for domestic, drinking, fishing, and industrial uses. This review study will be helpful for the policymakers and environmentalists to know about the status and sources of pollution in the lake water in the megacity which in turn assist to take necessary actions to mitigate the pollution level from the studied lakes of Dhaka city, Bangladesh. [ABSTRACT FROM AUTHOR]

Considerable amounts of heavy metals have contaminated the soil from potential manmade point and nonpoint sources such as industry, urbanisation and agriculture. In both managed and natural ecosystems, beneficial plant--microbe interactions play a significant role improving the growth and health of plants, and could be applied for improving soil fertility as well as crop productivity. Additionally, plant--microbe interactions could be utilised in bioremediation of heavy metal-contaminated soils. The efficiency of phytoremediation can be improved with the aid of plant-growth-promoting bacteria (PGPB), which can change metals to bioavailable and soluble forms. PGPB perform remediation through processes such as production of siderophores, organic acids and biosurfactants, biomethylation, redox processes, phosphorus solubilisation, nitrogen fixation and iron sequestration. These processes improve plant growth and increase plant biomass along with phytoremediation. A crucial solution to the problem of heavy metal contamination might be an appropriate understanding of hyperaccumulator plants and their interaction with microbes. Emerging strategies for either enhancing or reducing the bioavailability of heavy metals in the rhizosphere, such as improving plant establishment, growth and health can significantly accelerate the heavy metal bioremediation process. In this review, we feature the function of PGPB to assist phytoremediation of heavy metals as an eco-friendly and economical approach. [ABSTRACT FROM AUTHOR]

Rice is the staple food of Bangladeshi people and is consumed at least twice a day. Thus, the presence of toxic metals in rice grains has become a major public health concern in Bangladesh. The present research was conducted to investigate the concentrations of toxic metals in rice grains and their possible human health risks in the Tangail district of Bangladesh. Toxic metals were measured by using an inductively coupled plasma mass spectrometer (ICP-MS), and the mean concentrations of toxic metals in rice samples were found in order of Cr > Pb > Ni > As > Cu > Cd. The concentrations of Cr, Pb, As, and Cd in the studied rice grain samples exceeded the FAO/WHO standard values for food samples by 100%, whereas the Ni concentrations by 10%. The principal component analysis (PCA) revealed significant anthropogenic contributions of Cr, Ni, As, and Pb concentrations in rice grains. The metal concentrations in rice grain samples showed strong significant correlations by forming primary clusters with each other. The estimated daily intake (EDI) values of Cr, Ni, As, Cd, and Pb from all samples were higher than the maximum tolerable daily intake (MTDI) allowed. The total targeted hazard quotient (TTHQ) values of Cu, Ni, As, Cd, and Pb also exceeded the threshold value of 1.00, indicating a potential non-carcinogenic risk. The estimated target carcinogenic risk of As was higher than the USEPA threshold level 10−4 (0.0001) indicating increased risk of cancer for adults and children in the study area. [ABSTRACT FROM AUTHOR]

Heavy metals are toxic in nature, and their contamination in foodstuff is a matter of concern for human health. The present study was conducted to assess the concentrations of chromium, nickel, copper, arsenic, cadmium, and lead in rice and vegetables and their possible human health risks in Tangail district, Bangladesh. Metals were measured by inductively coupled plasma mass spectrometry (ICP-MS) after microwave digestion system. The average values of Cr, Ni, Cu, As, Cd, and Pb in rice and vegetables were 16.26, 16.11, 13.99, 2.28, 1.86, and 7.93 mg/kg, respectively. The average metal concentration in rice and vegetable species was in the decreasing order of okra > chili > bitter gourd > papaya > brinjal > bean > bottle gourd > rice > cucumber > sponge gourd > Indian spinach. The estimated daily intake (EDI) values of all the metals except Cu were higher than the maximum tolerable daily intake (MTDI). The target hazard quotients (THQs) values of Ni, Cu, As, Cd, and Pb exceeded the threshold value of 1 through consumption of rice and vegetables, indicating significant health risks to both adult and children. The target carcinogenic risk (TR) of As and Pb through consumption of rice and vegetables was higher than the USEPA threshold level (10−4). From the health point of view, this study clearly revealed that consumption of these contaminated rice and vegetables definitely poses carcinogenic and non-carcinogenic risks. [ABSTRACT FROM AUTHOR]

Metal accumulation (As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) in Korotoa River sediment was studied in order to determine the metal content, distribution, sources, and their possible ecological impacts on the riverine ecosystem. Our study found significant spatial patterns of toxic metal concentration and principal coordinate analysis (PCoA) accounted for 45.2% of spatial variation from upstream to downstream. Metal contents were compared to sediment quality standards and found all studied metal concentrations exceeded the Threshold Effect Level (TEL) whereas Cr and Ni surpassed probable effect levels. All metal concentrations were higher than Average Shale Value (ASV) except Mn and Hg. The positive matrix factorization (PMF) and absolute principal component score-multiple linear regression models (APCS-MLR) were applied to identify promising sources of metals in sediment samples. Both models identified three potential sources i.e. natural source, traffic emission, and industrial pollution, which accounted for 50.32%, 20.16%, and 29.51% in PMF model whereas 43.56%, 29.42%, and 27.02% in APCS-MLR model, respectively. Based on ecological risk assessment, pollution load index (7.74), potential ecological risk (1078.45), Nemerow pollution index (5.50), and multiple probable effect concentrations quality (7.73) showed very high contamination of toxic metal in sediment samples. [Display omitted] • Toxic metals contamination with sources in the sediment of Korotoa River were studied. • Principal coordinate analysis accounted for 45.2% of spatial variation. • Both PMF and APCS-MLR model identified natural source, traffic emission, and industrial pollution. • PLI, PER, P N , and mPECQ showed very high contamination of metals in sediment. [ABSTRACT FROM AUTHOR]

This research aims to investigate the future changes in summer monsoon rainfall and temperature in Bangladesh. The study revealed that INM-CM5-0 is the best model for projecting temperature, while BCC-CSM2-MR is the best model for projecting rainfall over Bangladesh. Using data from a large ensemble of 27 models from CMIP6, the study examined the rainfall and temperature change projections of Bangladesh during the twenty first century relative to the reference period (1981–2014) under SSP2–4.5 and SSP5–8.5. Under SSP2-4.5 and SSP5-8.5, the multi-model ensemble monsoon mean rainfall over Bangladesh will fluctuate between 40 and 260 mm and 100 and 900 mm, respectively. In most parts of the country's north, northeastern, and western regions, the projected changes in spatial patterns of monsoon rainfall indicate an increase in rainfall. The projected temperature indicated that Bangladesh's northwest and west-central areas could face the most significant rise in temperatures, surpassing 3.8 °C under SSP5-8.5. [ABSTRACT FROM AUTHOR]

The recent COVID-19 pandemic has imposed threats on both physical and mental health since its outbreak. This study aimed to explore the impact of the COVID-19 pandemic on mental health among a representative sample of home-quarantined Bangladeshi adults. A cross-sectional design was used with an online survey completed by a convenience sample recruited via social media. A total of 1,427 respondents were recruited, and their mental health was assessed by the DASS-21 measure. The prevalence of anxiety symptoms and depressive symptoms was 33.7% and 57.9%, respectively, and 59.7% reported mild to extremely severe levels of stress. Perceptions that the pandemic disrupted life events, affected mental health, jobs, the economy and education, predictions of a worsening situation, and uncertainty of the health care system capacities were significantly associated with poor mental health outcomes. Multivariate logistic regressions showed that sociodemographic factors and perceptions of COVID-19 significantly predict mental health outcomes. These findings warrant the consideration of easily accessible low-intensity mental health interventions during and beyond this pandemic. [ABSTRACT FROM AUTHOR]

Nitrogen (N) plays a key role for plant life cycle. It is available in agricultural soils as the form of nitrate and ammonium (NH4+) where nitrate (NO3−) is a major nutrient. Plants are able to sense NO3− in their environment, allowing them to quickly respond to the dramatic fluctuations of its availability. As a main feature of plant autotrophy, assimilation of inorganic N is not only of fundamental interest to the crop, but also a crucial factor in crop productivity. Furthermore, over the last couple of years, N sensing has been shown to be affected by different external factors, which act as local signals to trigger systemic signaling coordinated by mobile signals in plants body. During recent years, a breakthrough arising from the improved knowledge is a better understanding of NO3− integration and hormone signaling pathways of plants that explains the extraordinary developmental plasticity of NO3− response. This review highlights the novel aspect of N responsive sensors, transporters, and signaling molecules in plants with a brief introduction on the metabolic pathways and discusses their potential roles in N sensing. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the spatio-seasonal variations in water quality and suitability of the Shitalakhya river, an economically important and ecologically critical urban river in Bangladesh, along with associated influencing factors and possible sources of water pollution. Therefore, surface water samples were collected monthly from five sampling sites, and fourteen water quality parameters were evaluated. The results showed that some studied water quality parameters, e.g., temperature, TDS, TA, TH, NO2–, and NO3–, exceeded the maximum allowable limit, whereas statistically significant (p <.05) variations were observed among pre-monsoon (February–May), monsoon (June–September), and post-monsoon (October–January) seasons. The values of water quality index (WQI) exhibited that the water quality was found to be very poor to unsuitable for drinking, fisheries, or aquatic environment. The principal component analysis (PCA) extracted two PCs explaining 91.092% of the total variance, which suggested that the variations in water quality are attributed mainly to point and nonpoint sources of contamination including municipal and industrial wastewater discharge, and agricultural runoff of inorganic fertilizers. The cluster analysis (CA) also showed relative spatial and seasonal variations in river water quality, indicating the influence of hydrological changes and pollution sources. The study revealed that the water of the Shitalakhya river is highly polluted and potentially hazardous for human uses, and thus more attention should be given to safeguard such an important urban river. [ABSTRACT FROM AUTHOR]

Groundwater is an essential resource in the Sundarban regions of India and Bangladesh, but its quality is deteriorating due to anthropogenic impacts. However, the integrated factors affecting groundwater chemistry, source distribution, and health risk are poorly understood along the Indo-Bangla coastal border. The goal of this study is to assess groundwater chemistry, associated driving factors, source contributions, and potential non-carcinogenic health risks (PN-CHR) using unsupervised machine learning models such as a self-organizing map (SOM), positive matrix factorization (PMF), ion ratios, and Monte Carlo simulation. For the Sundarban part of Bangladesh, the SOM clustering approach yielded six clusters, while it yielded five for the Indian Sundarbans. The SOM results showed high correlations among Ca2+, Mg2+, and K+, indicating a common origin. In the Bangladesh Sundarbans, mixed water predominated in all clusters except for cluster 3, whereas in the Indian Sundarbans, Cl−-Na+ and mixed water dominated in clusters 1 and 2, and both water types dominated the remaining clusters. Coupling of SOM, PMF, and ionic ratios identified rock weathering as a driving factor for groundwater chemistry. Clusters 1 and 3 were found to be influenced by mineral dissolution and geogenic inputs (overall contribution of 47.7%), while agricultural and industrial effluents dominated clusters 4 and 5 (contribution of 52.7%) in the Bangladesh Sundarbans. Industrial effluents and agricultural activities were associated with clusters 3, 4, and 5 (contributions of 29.5% and 25.4%, respectively) and geogenic sources (contributions of 23 and 22.1% in clusters 1 and 2) in Indian Sundarbans. The probabilistic health risk assessment showed that NO 3 − poses a higher PN-CHR risk to human health than F− and As, and that potential risk to children is more evident in the Bangladesh Sundarban area than in the Indian Sundarbans. Local authorities must take urgent action to control NO 3 − emissions in the Indo-Bangla Sundarbans region. [Display omitted] • First attempts at using unsupervised learning model to drive groundwater chemistry in the study region. • Mineral dissolution is affected more than anthropogenic inputs, causing an unstable equilibrium in groundwater. • The non-carcinogenic risk of NO 3 − was identified as more threatening to children in the Bangladesh Sundarbans. [ABSTRACT FROM AUTHOR]

Heavy metals contamination is a serious threat for the toxicity and bioaccumulation in food chain. Aquatic environment contamination has become a global concern because they have toxic effects on fishes. The concentration of heavy metals like arsenic (As), chromium (Cr), cadmium (Cd) and lead (Pb) in commercially fishes (Tenualosa ilisha, Gudusia chapra, Otolithoides pama, Setipinna phasa, Harpadon nehereus, Polynemus paradiseus, Sillaginopsis panijus and Pampus chinensis) collected from Karnaphuli River in Bangladesh were (fish muscles) assessed with health risk during summer and winter season. These heavy metals are toxic in nature and can come to human food chain through fish consumption. The mean concentration of As, Cr, Cd and Pb was found 1.59, 0.73, 0.41 and 1.13 mg/kg in summer and 1.81, 0.92, 0.52 and 1.45 mg/kg in winter, respectively. Cr and Pb concentration of all fish species were found to be higher than Food and Agriculture Organization (FAO)/(WHO) tolerable concentration assuming these metal pose risk to human. The hazard quotients value of heavy metals in Harpadon nehereus was found higher than one resulting non-carcinogenic risk for consumption of this fishes. Carcinogenic risk value for As and Pb were remaining 10−6 to 10−4 indicating continuously consumption of studied fish samples may cause cancer risk. [ABSTRACT FROM AUTHOR]

Dengue, a mosquito-borne viral infectious disease, causes a high morbidity and mortality in tropical and subtropical areas of the world. In Nepal, the first case of dengue was reported in 2004 followed by frequent outbreaks in subsequent years, with the largest being in 2019 taking the death toll of six. It is reported that the number of dengue fever cases are soaring in Nepal spreading from the plains to more hilly regions. This might have serious public health implications in the future when combined with other factors, such as: global warming, lack of early detection and treatment of dengue, lack of diagnostic facilities, poor healthcare systems and mosquito control strategies. Nepal, thus, needs a cost-effective mosquito control strategy for the prevention and control of dengue. The Wolbachia-mediated biological method of the dengue control strategy is novel, economic, and environment-friendly. It has been successfully trialed in several areas of dengue-prone countries of the world, including Australia, Malaysia, Vietnam etc. resulting in significant reductions in dengue incidence. Given the lack of effective vector control strategy and weak economic condition of the country along with the persistence of climate and environment conditions that favors the host (Aedes mosquito) for Wolbachia, this approach can be a promising option to control dengue in Nepal. [ABSTRACT FROM AUTHOR]

Meretrix lyrata which is under the family of Veneridae and under the order of Venerida, is a nutritionally and economically important edible mussel in Bangladesh. However, studies on species identification and nutritional value in M. lyrata are scarce. Therefore, a detailed investigation was conducted on (i) species identification of the common edible mussel through DNA-barcoding and morphometrics, (ii) reproductive features, such as size at sexual maturity, spawning, and peak-spawning seasons under different environmental factors, and (iii) nutritional status through proximate analysis of M. lyrata mussel collected from the Bay of Bengal, Bangladesh. The results indicated that the size at sexual maturity for M. lyrata was 4.2 cm and the spawning seasons were significantly affected by the dissolve oxygen and salinity. The study also demonstrated that the spawning of M. lyrata occurred from January to June and December while peak spawning season was May in the Bay of Bengal. The higher protein and moisture contents with lower fat in M. lyrata indicated that are value-added seafood with higher nutritional values for consumers. [Display omitted] • The size at sexual maturity for M. lyrata was 4.2 cm. • Spawning of M. lyrata occurred from January to June and December while peak spawning season was May in the Bay of Bengal. • M. lyrata were found enriched with higher protein and moisture. [ABSTRACT FROM AUTHOR]