In the present study, we studied the concentrations and proportions. We identified the potential sources and health risks of 12 probably carcinogenic polycyclic aromatic hydrocarbons (PAHs) in rice grain from 31 sites in Thailand and Myanmar. The findings showed that PAH concentrations in rice grain samples from Thailand and Myanmar were in the range of 0.09 to 37.15 ng.g-1 with an average value of 18.22 ± 11.76 ng.g-1 and 0.07 to 150.73 ng.g-1 with an average value of 34.70 ± 40.57 ng.g-1, respectively. The majority group of PAHs in the rice grain samples from Thailand were the five-ring PAHs (78%), followed by four-rings (12%) and three-ring PAHs (9.5%), respectively, while for Myanmar was the five-ring PAHs were the majority (64.02%), followed by six-rings (15.22%) and four-ring PAHs (13.58%), respectively. The diagnostic ratio analysis suggested that pyrogenic origin is a major source of PAHs, and principal component analysis (PCA) identifies the incomplete combustion of fuel as likely the primary source of emissions source of PAHs contamination in rice grain samples. The total values of incremental lifetime cancer risk (ILCR) of PAH content of rice grain for children and adults were 1.95 × 10-8 and 1.44 × 10-8, respectively, for Thailand and 1.83×10-7 and 1.35×10-7 for Myanmar, which showed that the incremental lifetime cancer risk from rice grain was lower than the baseline set is considered to be safe levels.

The amount of plastic waste produced yearly is significantly increasing. Approximately 300-400 million metric tons of plastic waste are produced yearly. One of the dominant plastic wastes is a metalized film, a shiny, non-homogeneous polymer used in packaging that is considered the least recycled. Meanwhile, partition walls in buildings are traditionally made of concrete masonry, one of the most utilized materials in the construction industry globally, consumed yearly by about 11 billion metric tons. Because of the excessive use of concrete, the necessary raw materials are undeniably depleting, therefore demanding some alternatives. Polymethyl methacrylate (PMMA) is one option that can be utilized as an alternative because of its remarkable characteristics better than that of the traditional. This paper proposed the utilization of PMMA in fabricating the hollow panel filled with shredded waste metalized film packaging resulting in the lightweight wall panel being used as an alternative to concrete masonry for constructing partition walls. After the experiment, PMMA produced compressive strength of 75.30-84.30MPa, a tensile strength of 52.00-59.10MPa, a flexural strength of 102.00-107.00MPa, and water absorption of 0.80-0.90%. Also, shredded waste metalized films add aesthetic to the panel and are complemented by the remarkable transparency of PMMA. In conclusion, using this lightweight wall panel instead of traditional concrete masonry partition walls will reduce plastic waste in landfills and the raw materials necessary to produce concrete.

Pollutants like arsenic, chromium, or other toxic heavy metals have the most dreadful impact on humans or animals and also become a threat worldwide. Introducing these contaminants into the environment is not just due to the chemical industry but also coexists in combined form in underground rocks, contaminating groundwater during breakdown. Epidemics are now largely blamed on toxic pollution in many different nations worldwide. The issue has gotten worse in underdeveloped nations, where metal contamination of the groundwater affects more than a million people. Different techniques are used to remove toxic pollutants from water, but most are expensive and energy intensive. Adsorption is preferable for removing contaminants such as heavy metals or chemical dyes. As nanomaterials have been demonstrated to be more effective as nanocomposites, we used an adsorbent of nanomaterial to use the adsorption approach. These materials have become more well-liked because of their useful applications and improved characteristics. Magnetic synthesized nanocomposites have magnetic properties, which become beneficial for adsorption as it enhances adsorption capacity. The insertion of the plant or aggregate waste material for nanocomposite synthesis inhibits the growth of bacteria or other microorganisms, preventing the material from getting infected if it is in the environment. In this review paper, we have focused on the green synthesis of nanomaterials used for water treatment.

The reduction of oily sludge and scum with high water content by hot washing and analysis of the main factors that affect the reduction and oil recovery rate of oily sludge and scum in hot washing were investigated. Best process conditions for the reduction of tank bottom sludge, refining sludge, and oily scum were carried out, which can make the oil recovery rate and reduction rate of tank bottom sludge after reduction reach 96.30% and 93.00%, respectively, the oil recovery rate and reduction rate of refining sludge after reduction reach 95.36% and 92.60% respectively, and the oil recovery rate and reduction rate of oily scum after reduction reach 95.92% and 93.60% respectively. After treatment, the oil content of the residue is reduced to below 5.1%, and the water content is reduced to below 59.0%. Oil content in the separated water is lower than 200 mg.L-1, and the water content in the separated oil is lower than 0.2%, far below the requirement of 0.5% in the oilfield’s crude oil gathering and transportation standard.

The neurotoxic effects of exposure to low levels of the pesticide imidacloprid (IMI) and the effect of curcumin are of current interest when exposure occurs during early development. Male weanlings of Swiss albino mice (21 days old) were given 1 mg.kg-1 body weight (1/130 of LD50 and 2 mg.kg-1 body weight (1/65 of LD50) of imidacloprid and Curcumin (100 mg/kg body wt.) by oral gavage from postnatal day 21 to postnatal day 60. Young adult offspring were studied for behavioral parameters and learning ability using open field and Morris water maze. After completing the behavioral test, brains were processed for acetylcholine esterase activity and antioxidant enzyme estimation. The level of lipid peroxidation and activity of catalase, superoxide dismutase, and glutathione were assayed. In the present study, parameters such as locomotor activities and cognitive skills were not affected compared to lower doses of imidacloprid in the open field and Morris water test. However, activities and levels of antioxidant enzymes such as catalase and lipid peroxidation were found to be altered. In contrast, superoxide dismutase, acetylcholine esterase activity, and glutathione remained unchanged compared to the control. This suggests that subchronic exposure to low doses of IMI can lead to significant alterations in the enzymes of antioxidant protective systems such as catalase and lipid peroxidation. Co-treatment with curcumin was able to restore the activities of the affected enzymes in comparison with the control.

Lipases are utilized in biodiesel production utilizing various types of substrates. The use of lipase in bioenergy production aims to reduce energy crises and environmental pollution. Lipase-producing indigenous bacteria Bacillus licheniformis (Accession no. OP56979) and Bacillus rugosus (Accession no. OP56980) were isolated from various oil-contaminated sites. The isolated potential lipolytic bacteria were screened for maximum lipase production. Then, the bacteria showing the highest lipolytic activity were subjected to identification using the 16s rRNA technique while other isolated were identified biochemically. Lipase [LipBL-WII(c)] from Bacillus licheniformis having the highest lipolytic activity expressed various characteristics. Characterization of crude LipBL-WII(c) expressed that it showed stability in a wide range of pH (4 to 10) with optimum lipolytic activity observed at pH 8. It was then found to be active at a temperature range from 20°C to 80°C with optimal at 50°C. Lipase activity was also stimulated in metal ions such as Ca+1, Mg2+, and Zn2+ the most. Furthermore, LipBL-WII(c) retained lipolytic activity in the presence of various organic solvents and surfactants. The kinetic parameters (Km and Vmax) for LipBL-WII(c) were ascertained using Lineweaver- Burk plot. LipBL-WII(c) showed a potential for biodiesel production using olive oil as a source. Lipase gave 84% yield of biodiesel production from olive oil. Thus, it could be employed as a potential candidate for green biodiesel production using oil sources.

Nanoparticles are an important tool for new updations and advancements in diverse sectors. The inorganic metal and metal oxide nanoparticles have enormous research interest because of their great relevance in medicine, wastewater treatment, catalysis, biotechnology, and in the formation of energy storage devices. The NiO NPs can be synthesized using different physical and chemical methods and exploring all their possible applications. Green synthesis is the easy, safe, and effective nanoparticle synthesis route. Green metal and metal oxide nanoparticle syntheses provide the most affordable, convenient, and biocompatible approach for fabricating NiO NPs. This way is a good alternative to the conventional methods of synthesis. Green synthesis, being more constructive, is widely used in research and gives promising outcomes. This review highlighted the unique feature of the NiO nanoparticles. This paper brings forth the usage of green synthesis for synthesizing NiO nanoparticles. It also provides readers with a collective review of the recent development in the green synthesis of NiO NPs and their potential application in different fields.

The paper investigated the adsorption of Cr(VI) on biochar in simulated wastewater by static adsorption method, Fourier Transform Infrared spectra (FTIR), Raman, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscope (TEM) characterization analysis. The results show that biochar can effectively remove Cr(VI) in wastewater, and the adsorption equilibrium can be quickly reached within 100 min. The kinetic analysis shows that the quasi-second-order kinetic model can better fit the kinetic process of Cr(VI) adsorption by biochar, which shows that the main mechanism of the adsorption is the chemical bonding cooperation between Cr(VI) and the functional groups on the surface of biochar. Fit analysis of the isotherm at different temperatures shows that temperature increase promotes the adsorption of Cr(VI) on biochar, and thermodynamic analysis reveals that the adsorption of Cr(VI) on biochar is a spontaneous endothermic process. The Freundlich model effectively fits the adsorption isotherm of Cr(VI), indicating that the surface of biochar is uneven and Cr(VI) has undergone multilayer adsorption. The adsorption isotherm of Cr(VI) under the influence of HA and FA can be effectively fitted by the Freundlich model, and the adsorption efficiency is the highest when FA is added. The national analysis of Fourier Transform Infrared spectra (FTIR), Raman, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and transmission electron microscope (TEM) further reveals the bond cooperation between Cr(VI) and the surface functional groups of biochar. The results show that biochar has potential application value in treating chrome-containing wastewater.

Hospital waste is a burning issue that severely impacts public health. This study in three big hospitals in Lahan and Rajbiraj, Nepal, for one year (2019 March-2020 February) aims to analyze some parameters that directly help waste management properly. Field study, questionnaire, and interview methods were followed. The average moisture content of wastes of all three hospitals was 55.79%. There was no variance in the three hospitals’ moisture content values of wastes (F = 1.89 P-value = 0.165 F crit = 3.284917651). The average temperature of dumped waste was 23.23°C, and the temperature of all three hospitals was closely associated (F = 0.998, P-value 0.379, Fcrit = 3.28). The average pH value of wastes from the three hospitals was 4.44, and it from all three sites was strongly associated (F = 0.0668, P-value 0.935, Fcrit = 3.284). There was no relation between income and types of waste production (ꭕ2 = 0.8, df = 4, significance level = 0.05), but there was a high association between the level of income and amount of waste production. There was a high association between the nature of hospitals and types and the amount of waste (ꭕ2 = 77.09, df = 4, Significance level = 0.05). In Sagarmatha Choudhary eye hospital Lahan, there was no significant correlation between the number of patients and the amount of waste (Correlation = -0.187889 at 0.05% significance level). Unique Hospital Rajbiraj showed a correlation between the number of patients and the amount of waste (correlation = 0.1183 at 0.05% significance level). In Gajendra Narayan Singh Hospital, there was a correlation between the number of patients and the amount of waste (Correlation = 0.3453, at 0.05% significance level). There was no association between the qualification of respondents and their responsibilities regarding the services provided by hospitals (ꭕ2 = 1.43, df = 6, Significance level = 0.05). It is recommended for better management and installment of modern technologies for waste management.

In this study, waste tires were used to develop activated carbon for the adsorption of Cr(VI) from aqueous solutions, and an artificial neural network (ANN) model was applied to predict the adsorption efficiency of waste-tire activated carbon (WTAC). SEM and FTIR were used to characterize the developed WTAC. A three-layer ANN with different training algorithms and hidden layers with different numbers of neurons was developed using 79 data sets gathered from batch adsorption experiments with different initial Cr(VI) ion concentrations, contact periods, temperatures, and doses. Conjugate gradient backpropagation of Powell-Beale restarts (traincgb) was found to be the best training algorithm among all the training algorithms, with an RMSE of 5.894 and an R2 of 0.985. The ANN topology had 4, 8, and 4 neurons in the input, hidden, and output layers. The correlation coefficient of the ANN models of Cr(VI) ion adsorption efficiency is 0.977.