Tobacco products are widely recognized as a major contributor to death. Cigarette smoke contains several toxic chemicals including heavy metals particulate causing high health risks. However, limited information has been available on the health risks associated with the heavy metals in cigarettes commonly sold in the Bangladeshi market. This study evaluated the concentrations and potential health risks posed by ten concerned heavy metals in ten widely consumed cigarette brands in Bangladesh using an atomic absorption spectrometer. The concentration (mg/kg) ranges of heavy metals Pb, Cd, Cr, As, Co, Ni, Mn, Fe, Cu, and Zn vary between 0.46-1.05, 0.55-1.03, 0.80-1.2, 0.22-0.40, 0.46-0.78, 2.59-3.03, 436.8-762.7, 115.8-184.4, 146.6-217.7, and 34.0-42.7, respectively. We assume that the heavy metals content among cigarette brands is varied due to the differences in the source of tobacco they use for cigarette preparation. The carcinogenic risks posed by heavy metals follow the order of Cr > Co > Cd > As > Ni > Pb, while the non-carcinogenic risks for Cu, Zn, Fe, and Mn were greater than unity (HQ > 1), except for Fe. The existence of toxic heavy metals in cigarette tobacco may thus introduce noticeable non-carcinogenic and carcinogenic health impacts accompanying inhalation exposure. This study provides the first comprehensive report so far on heavy metal concentration and associated health risks in branded cigarettes commonly sold in Bangladesh. Hence, this data and the information provided can serve as a baseline as well as a reference for future research and have potential implications for policy and legislation in Bangladesh.
In order to efficiently recycle waste polyethylene terephthalate (PET) bottles, this study aimed to enhance the hydrolysis process to convert PET bottle into valuable terephthalic acid (TPA) by developing effective and reusable Ni/γ-Al2O3 catalysts. A series of Ni/γ-Al2O3 catalyst was prepared by the impregnation method with different Ni loadings (5-15 wt%) and was characterized by various techniques including XRD, SEM-EDX, and N2 adsorption-desorption. The prepared catalysts were employed in the catalytic hydrolysis of PET under varied influencing factors, namely reaction temperature (220-280 °C), reaction time (20-60 min), and Ni loading. The response surface methodology (RSM) was used to optimize the operating condition to produce the maximum TPA yield, and the optimal values were determined as follows: reaction temperature = 267.07 °C, reaction time = 48.54 min, and Ni loading = 12.90 wt%, giving the highest TPA yield of 97.06%. The R2, F-value, and P-value of the analysis of variance (ANOVA) were 0.9982, 424.96, and <0.0001, respectively, indicating a good fit of the model. The results from XRD and FTIR measurement of the produced TPA indicated the high purity and comparable chemical structures to the TPA standard. In addition, the 12.9Ni/Al catalyst exhibited high catalytic activity in repeated cycles of hydrolysis process of PET and could be regenerated by calcination to restore its catalytic activity. This finding could be a promising alternative for an effective TPA recovery from waste plastic bottles.
Belt and Road Initiative (BRI) countries have benefited greatly from the intelligent growth of the green economy made possible by the widespread adoption of internet and mobile phone technologies. In addition, renewable energy consumption endorses sustainable development. Therefore, the purpose of this research is to determine if the use of information and communication technology (ICT) and renewable energy consumption has an effect on sustainable development in BRI countries, while using the augmented mean group (AMG) model, AMG robustness test, and panel Dumitrescu-Hurlin causality test to get robust results. According to the results of the study, the information and communication technology, renewable consumption, human capital, and urbanization reduces the emission of carbon dioxide emission in BRI countries while economic growth enhances the CO2 emission. Therefore, it is recommended that BRI countries increase their inter-regional cooperation in order to boost investment in renewable energy, effectively use the spillover effect of technology and knowledge, and end the resource curse in environmental policy. Based on the results, the authors of this paper propose a number of important steps toward environmental sustainability.
In the face of the challenge of balancing urban economic development and environmental protection, the concept of a healthy city has emerged as a promising model for sustainable urban development. This study empirically investigates the impact of healthy city construction on green growth by utilizing a difference-in-difference model estimation on a panel dataset of 279 Chinese prefecture-level cities from 2007 to 2019. The findings reveal that healthy city construction significantly contributes to green growth, particularly in pilot cities, and this effect is observed across cities of different sizes and economic bases. Additionally, we identify two channels through which healthy city construction promotes green growth: enhancing innovation capacity and enriching human resources. These findings have implications not only for Chinese cities navigating the path towards green growth but also for other developing nations striving for economic transformation and environmentally sustainable development.
In light of the adverse environmental impact of the R134a refrigerant, replacing it with a more environmentally friendly refrigerant has become imperative than ever. This study presents an experimental investigation into the utilization of R152a and R134a refrigerants in a vapor compression refrigeration system employing a variable displacement oil-free linear compressor. The potential for the replacement of R134a with R152a was examined based on energy, environmental, and economic performance analyses. The outcomes indicated that R152a exhibited a higher coefficient of performance (COP) in comparison to R134a under identical operating conditions. Specifically, when the pressure ratio was 2.0 and the piston stroke was 11 mm, R152a's COP was 13.0% higher than R134a. It was also discovered that reducing the operating stroke and increasing the pressure ratio could effectively lower CO2 emissions and total costs. Under the 2.0 pressure ratio and 9-mm piston stroke, R134a produced 1082.4 kg more CO2 emissions than R152a, representing a 209% increase. In addition, the R152a and R134a total cost was reduced by 8.3% with the 2.5 pressure ratio and 11-mm piston stroke. Notably, the results of the current study demonstrated that R152a outperformed R134a in energy consumption, environmental friendliness, and economy in oil-free linear compressor refrigeration systems. R152a used less electric power, generated fewer CO2 emissions, and naturally reduced predicted running costs in order to maintain the same COP.
The foremost purpose of the study is to establish a point that an economy of G-7 countries has an abundance of resources to tackle the environmental changes that occur in the world, but these countries are still behind the line because in this modern era, environmental performance changes their shape, dimension, and nature very frequently and create a huge impact on globalization of world economy. To fill this gap, we use green investment, institutional quality, and economic growth on environmental performance for this, we use four proxies for green investment and three proxies for greenhouse gas, and we also use six proxies of institutional quality to do this using period of 1997 to 2021. Moreover, we have used the panel nonlinear autoregressive distributed lag method to evaluate the long-run and short-run asymmetric effects of green investment, institutional quality, and economic growth on greenhouse gas emissions. The findings of the study affirm that the positive change of green investment has a positive and significant relationship with environmental performance, while the negative change of green investment has a significant and positive influence with environmental performance in the long run. Furthermore, the outcomes demonstrate that the positive shock of institutional quality has a positive and significant relationship with environmental performance, while the negative shock of intuitional quality has a significant and positive association with environmental performance in the long run, whereas positive change in economic growth has a positive and significant with the environmental performance, while the negative change of economic growth has a positive effect with environmental performance in the long run. This study finds future precautions that institutional quality has to perform exceptionally and shows results very rapidly, while green investment with economic growth has also made a deadly combination to control greenhouse gas emission, so the role of G-7 countries is pretty clear and straight. Furthermore, it is suggested that governments and policymakers take a proactive stance to promote resource acquisition and investment across all industries. To reduce gas emissions, public interest might also be complementary to private ones. So, economic policymakers, specifically in G-7 countries, should consider strategies that support sustainable economic growth.
Multiclass of endocrine disrupting chemicals (EDCs) such as nine perfluoroalkyl and polyfluoroalkyl substances (PFAS), five bisphenols, and four parabens were analysed in tap water samples from Malaysia's Klang Valley region. All samples were analysed using liquid chromatography mass tandem spectrometry (LC-MS/MS) with limit of quantitation (LOQ) ranged between 0.015 and 5 ng/mL. Fifteen of the 18 EDCs were tested positive in tap water samples, with total EDC concentrations ranging from 0.28 to 5516 ng/L for all 61 sampling point locations. In a specific area of the Klang Valley, the total concentration of EDCs was found to be highest in Hulu Langat, followed by Sepang, Putrajaya, Petaling, Kuala Lumpur, Seremban, and Gombak/Klang. PFAS and paraben were the most found EDCs in all tap water samples. Meanwhile, ethyl paraben (EtP) exhibited the highest detection rate, with 90.2% of all locations showing its presence. Over 60% of the regions showed the presence of perfluoro-n-butanoic acid (PFBA), perfluoro-n-hexanoic acid (PFHXA), perfluoro-n-octanoic acid (PFOA), perfluoro-n-nonanoic acid (PFNA), and perfluoro-1-octanesulfonate (PFOS), whereas the frequency of detection for other compounds was less than 40%. The spatial distribution and mean concentrations of EDCs in the Klang Valley regions revealed that Hulu Langat, Petaling Jaya, and Putrajaya exhibited higher levels of bisphenol A (BPA). On the other hand, Kuala Lumpur and Sepang displayed the highest mean concentrations of PFBA. In the worst scenario, the estimated daily intake (EDI) and risk quotient of some EDCs in this study exceeded the acceptable daily limits recommended by international standards, particularly for BPA, PFOA, PFOS, and PFNA, where the risk quotient (RQ) was found to be greater than 1, indicating a high risk to human health. The increasing presence of EDCs in tap water is undoubtedly a cause for concern as these substances can have adverse health consequences. This highlights the necessity for a standardised approach to evaluating EDC exposure and its direct impact on human populations' health.
Separation materials have received increasing attention given their broad applications in the management of environmental pollution. It is desired to balance the contradiction between high separation efficiency and selectivity of separation materials. The integration of ball-milled bone chars with electrospun membranes might achieve this balance. In this study, electrospun cellulose/chitosan/ball-milled bone char (CL/CS/MB) membranes were by well-dispersing ball-milled bone chars with nanoscale size (98.9-167.5 nm) and developed porosity (40.2-373.1 m2/g) in the electrospinning solvent. The synergistic integration of distributed MBs (5.4-31.5 wt.% of loading hydroxyapatite on the membrane matrix) allowed the efficient sorption of Pb(II) with fast kinetics (20.0 min), excellent capacity (219.9 mg/g at pH 5.0, T 298 K), and favorable selectivity coefficients (2.76-6.79). The formation of minerals was dominant for the selective sorption of Pb(II) by combining the spectral analysis and quantitative determination. The surface complexation with O-/reductive N-species, the cation exchange with inorganic Ca2+, the electrostatic attraction with deprotonated O-, and the cation-π coordination with the aromatic carbon via the π-electrons should be not ignored for the capture of Pb(II). This work demonstrated the feasibility of electrospun CL/CS/MB membranes as a promising candidate for the remediation of aquatic pollutants.
This review discusses the application of bacterial nanocellulose (BNC) and modified BNC in treating wastewater containing heavy metals and dye contaminants. It also highlights the challenges and future perspectives of BNC and its composites. Untreated industrial effluents containing toxic heavy metals are systematically discharged into public waters. In particular, lead (Pb), copper (Cu), cadmium (Cd), nickel (Ni), zinc (Zn), and arsenic (As) are very harmful to human health and, in some cases, may lead to death. Several methods such as chemical precipitation, ion exchange, membrane filtration, coagulation, and Fenton oxidation are used to remove these heavy metals from the environment. However, these methods involve the use of numerous chemicals whilst producing high amount of toxic sludge. Meanwhile, the development of the adsorption-based technique has provided an alternative way of treating wastewater using BNC. Bacterial nanocellulose requires less energy for purification and has higher purity than plant cellulose. In general, the optimum growth parameters are crucial in BNC production. Even though native BNC can be used for the removal of heavy metals and dyes, the incorporation of other materials, such as polyethyleneimine, graphene oxide, calcium carbonate and polydopamine can improve sorption efficiencies.
According to the United Nations Agenda, the 2023 sustainable environment is necessary to secure this planet's future; public-private partnerships investment in energy is crucial to sustainable development. The research examines the quantile association between public-private partnership ventures in energy and environmental degradation in ten developing nations, and data is used from January 1998-December 2016. The advanced econometrics quantile-on-quantile regression approach is used to control the issues of heterogeneity and asymmetric relationship. According to the quantile-on-quantile approach, there is a strong positive association between public-private partnerships in energy and environmental degradation in Argentina, Brazil, Bangladesh, and India. But the negative relationship is observed on different quantiles of China, Malaysia, Mexico, Peru, Thailand, and the Philippines. The findings suggest that the world needs to act as a single community and divert its resources toward renewable energy sources to control climate change; also, to accomplish the UN 15-year road map of Agenda 2023 with 17-SDGs; out of these 17 sustainable goals, SDG-7 is related to affordable and clean energy, SDG-11 is about sustainable cities and communities, and SDG-13 focuses on climate action for sustainable development.
Replacing conventional fine aggregates with spent mushroom substrate (SMS) is aimed at developing a sustainable lightweight masonry mortar. It is also an alternative solution for the current improper mushroom waste disposals. Density, workability, compressive strength, specific strength, flexural strength, ultrasonic pulse velocity, water absorption, sorptivity, and equivalent CO2 emission in relation to sand reduction in mortars containing 2.5-15.0% (by volume) SMS passing through a 4.75-mm sieve were investigated. As the percentages of replacement increased from 2.5 to 15.0%, the density of the SMS mortar reduced up to 34.8%, with corresponding compressive strengths of 24.96 to 3.37 MPa. Mixes with up to 12.5% SMS met the minimum compressive and flexural strengths as stated in the ASTM C129 standard. In addition, the equivalent CO2 emission of the mixes reduced 15.09% as the SMS content increased while cost-effectiveness increases up to 98.15% until 7.5% SMS replacement. In conclusion, the use of SMS as fine aggregates up to 12.5% is a viable mix design strategy for producing sustainable lightweight mortar with a lower carbon emission.
COVID-19 has affected all aspects of human life so far. From the outset of the pandemic, preventing the spread of COVID-19 through the observance of health protocols, especially the use of sanitizers and disinfectants was given more attention. Despite the effectiveness of disinfection chemicals in controlling and preventing COVID-19, there are critical concerns about their adverse effects on human health. This study aims to assess the health effects of sanitizers and disinfectants on a global scale. A total of 91,056 participants from 154 countries participated in this cross-sectional study. Information on the use of sanitizers and disinfectants and health was collected using an electronic questionnaire, which was translated into 26 languages via web-based platforms. The findings of this study suggest that detergents, alcohol-based substances, and chlorinated compounds emerged as the most prevalent chemical agents compared to other sanitizers and disinfectants examined. Most frequently reported health issues include skin effects and respiratory effects. The Chi-square test showed a significant association between chlorinated compounds (sodium hypochlorite and per-chlorine) with all possible health effects under investigation (p-value <0.001). Examination of risk factors based on multivariate logistic regression analysis showed that alcohols and alcohols-based materials were associated with skin effects (OR, 1.98; 95%CI, 1.87-2.09), per-chlorine was associated with eye effects (OR, 1.83; 95%CI, 1.74-1.93), and highly likely with itching and throat irritation (OR, 2.00; 95%CI, 1.90-2.11). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92-2.44). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92-2.44). The use of sodium hypochlorite and per-chlorine also had a high chance of having respiratory effects. The findings of the current study suggest that health authorities need to implement more awareness programs about the side effects of using sanitizers and disinfectants during viral epidemics especially when they are used or overused.
This study investigated the effect of different Co3O4-based catalysts on the catalytic decomposition of nitrous oxide (N2O) and on nitric oxide (NO) conversion. The experiments were carried out using various reaction temperatures, alkaline solutions, pH, mixing conditions, aging times, space velocities, impregnation loads, and compounds. The results showed that Co3O4 catalysts prepared by precipitation methods have the highest catalytic activity and N2O conversion, even at low reaction temperatures, while the commercial nano and powder forms of Co3O4 (CS) have the lowest performance. The catalysts become inactive at temperatures below 400 °C, and their activity is strongly influenced by the mixing temperature. Samples without stirring during the aging process have higher catalytic activity than those with stirring, even at low reaction temperatures (200-300 °C). The catalytic activity of Co3O4 PM1 decreases with low W/F values and low reaction temperatures. Additionally, the catalyst's performance tends to increase with the reduction process. The study suggests that cobalt-oxide-based catalysts are effective in N2O catalytic decomposition and NO conversion. The findings may be useful in the design and optimization of catalytic systems for N2O and NO control. The results obtained provide important insights into the development of highly efficient, low-cost, and sustainable catalysts for environmental protection.
Exposure of synthetic dye, such as methylene blue (MB), in water bodies led to a serious threat to living things because they are toxic and non-degradable. Amongst the introduced dye removal methods, membrane separation process can be considered a powerful technique for treating dye contamination. However, this method commonly suffered from drawbacks, such as short membrane lifetime, low permeability and selectivity. To overcome these issues, graphene oxide (GO) and titanium dioxide (TiO2) were used as additives to fabricate polyethersulfone (PES)- and polyvinylidene fluoride (PVDF)-based hybrid membranes via non-solvent-induced phase separation method. Prior to membrane fabrication, GO was synthesised via electrochemical exfoliation method assisted by customised triple-tail surfactant. The potential of PES- and PVDF-based hybrid membranes for wastewater treatment has been discussed widely. However, direct comparison between these two polymeric membranes is not critically discussed for MB dye separation application yet. Therefore, this study is aimed at evaluating the performance of different types of polymers (e.g. PES and PVDF) in terms of membrane morphology, properties, dye rejection and antifouling ability. Results showed that the incorporation of GO and TiO2 alters the morphology of the fabricated membranes and affects dye rejection further, as well as their antifouling performance. In contrast with pristine membrane, PES-GO/TiO2 and PVDF-GO/TiO2 possessed high hydrophilicity, as indicated by their low contact angle (67.38° and 62.12°, respectively). Based on this study, PVDF-GO/TiO2 showed higher porosity value (94.88%), permeability (87.32 L/m2hMPa) and MB rejection rate (92.63%), as well as flux recovery ratio value of > 100% as compared with others. Overall, the incorporation of GO and TiO2 with PVDF polymer are proven to be effective hybrid materials of membrane fabrication for dye rejection application in the near future. The polymer material's intrinsic properties can affect the attributes of the fabricated membrane.
As clean water can be considered among the essentials of human life, there is always a requirement to seek its foremost and high quality. Water primarily becomes polluted due to organic as well as inorganic pollutants, including nutrients, heavy metals, and constant contamination with organic materials. Predicting the quality of water accurately is essential for its better management along with controlling pollution. With stricter laws regarding water treatment to remove organic and biologic materials along with different pollutants, looking for novel technologic procedures will be necessary for improved control of the treatment processes by water utilities. Linear regression-based models with relative simplicity considering water prediction have been typically used as available statistical models. Nevertheless, in a majority of real problems, particularly those associated with modeling of water quality, non-linear patterns will be observed, requiring non-linear models to address them. Thus, artificial intelligence (AI) can be a good candidate in modeling and optimizing the elimination of pollutants from water in empirical settings with the ability to generate ideal operational variables, due to its recent considerable advancements. Management and operation of water treatment procedures are supported technically by these technologies, leading to higher efficiency compared to sole dependence on human operations. Thus, establishing predictive models for water quality and subsequently, more efficient management of water resources would be critically important, serving as a strong tool. A systematic review methodology has been employed in the present work to investigate the previous studies over the time interval of 2010-2020, while analyzing and synthesizing the literature, particularly regarding AI application in water treatment. A total number of 92 articles had addressed the topic under study using AI. Based on the conclusions, the application of AI can obviously facilitate operations, process automation, and management of water resources in significantly volatile contexts.
Pristine tropical river systems are coming under increasing pressure from the development of economic resources such as forestry and mining for valuable elements. The Lebir catchment, north eastern Malaysia, is now under development as a result of unregulated tree felling and mining for essential and rare metals. Two sediment cores, one in the upstream reaches and the other from the downstream reaches, were taken from flood prone area of the Lebir River, Malaysia, and analysed for their elemental composition by XRF, specifically Al, Si, Fe, Ca, K, Mg, Mn, V, Cu, Ni, Pb, Cr, Zn, As, Th and U. Activities of fallout radionuclides, 137Cs and 210Pb were also determined to from a geochronological context. The elemental concentrations in the soils were assessed in terms of their enrichment factor and Si, Ca, K, Mg, Mn, V, Cu, Ni and Zn were found not to be enriched, whereas As, Th and U had elevated enrichment factors. The Th and U were particularly enriched in the downstream core indicating inputs from a tributary that drains a catchment with known deposits of Th and possibly U. The results suggest that the growth in economic development is fostering the transport of contaminants by the major rivers which, in turn, is contaminating the riverine floodplains. This points to the need for a more integrated and holistic approach to river basin management to maintain the environmental quality of these fragile aquatic systems.
In this paper, the technical-economic framework for designing of water pumping system based on photovoltaic clean energy with water tank storage is presented to supply drinking water of customers for remote areas. The objective function is to minimize the net present cost (NPC) (as economic index) including initial investment costs, maintenance, and replacement costs, and reliability constraint is defined as customer's water not supplied probability (CWNSP) as technical index. A meta-heuristic intelligent water drops algorithm (IWDA) is proposed to optimize the solar water pumping system considering NPC and CWNSP with high accuracy and speed of optimization in achieving the global solution. The simulation results show that the proposed method is capable of responding to customer's water demand by optimally sizing components and water storage tank based on IWDA which is inspired based on flowing the water drops in rivers by achieving the lowest cost with optimal reliability. The NPC of the system with CWNSP equal to 3.17 % is obtained 0.24 M$ for 6-m-high water extraction. The results showed that with increasing the water extraction height, the NPC increased, and the reliability also weakened. Moreover, the superiority of the IWDA is confirmed compared with particle swarm optimization (PSO) in designing a water pumping system with the lowest NPC.
In this study, palm oil mill effluent (POME) was treated using electrocoagulation, whereby the influencing factors including voltage, electrolysis time, and electrolyte amount were optimized to achieve the highest chemical oxygen demand (COD) and color removal efficiencies. Graphite was selected as electrode material due to its performance better compared to aluminum and copper. Response surface methodology (RSM) was carried out for optimization of the electrocoagulation operating parameters. The best model obtained using Box-Behnken design (BBD) were quadratic for COD removal (R2 = 0.9844), color reduction (R2 = 0.9412), and oil and grease removal (R2 = 0.9724). The result from the analysis of variance (ANOVA) was obtained to determine the relationship between factors and treatment efficiencies. The experimental results under optimized conditions such as voltage 14, electrolysis time of 3 h, and electrolyte amount of 13.41 g/L show that the electrocoagulation process effectively reduced the COD (56%), color (65%), and oil and grease (99%) of the POME treatment. Graphical abstract.
Freshwater scarcity, a problem that has arisen particularly as a result of the progressive environmental damage caused by human consumption patterns, is strongly associated with a loss of living quality and a drop in global socioeconomic development. Wastewater treatment is one of the measures being taken to mitigate the current situation. However, the majority of existing treatments employ chemicals that have harmful environmental consequences and low effectiveness and are prohibitively expensive in most countries. Therefore, to increase water supplies, more advanced and cost-effective water treatment technologies are required to be developed for desalination and water reuse purposes. Green technologies have been highlighted as a long-term strategy for conserving natural resources, reducing negative environmental repercussions, and boosting social and economic growth. Thus, a bibliometric technique was applied in this study to identifying prominent green technologies utilised in water and wastewater treatment by analysing scientific publications considering authors, keywords, and countries. To do this, the VOSviewer software and Bibliometrix R Package software were employed. The results of this study revealed that constructed wetlands and photocatalysis are two technologies that have been considered as green technologies applicable to the improvement of water and wastewater treatment processes in most scientific articles.
The reactive power control of a power system is discussed under two types of variables: continuous variables (e.g., generator bus voltages) and discrete variables (e.g., transformer taps and the size of switched shunt capacitors). This paper proposes a novel and powerful algorithm, named turbulent flow of water-based optimization (TFWO) as well as a new improved version of this algorithm, called θ-TFWO, for optimal reactive power distribution (ORPD) to reduce losses. The proposed method is applied to two large-scale IEEE 57-bus systems. Furthermore, to demonstrate the competitive performance of the suggested algorithm, its performance was compared to that of several other algorithms, including biogeography-based optimization (BBO), social spider algorithm (SSA), and optics inspired optimization (OIO), in terms of solving the ORPD problem. The results confirmed the robustness and effectiveness of the proposed method as a powerful optimizer applicable to optimal reactive power distribution in power systems.