The damage potential of cigarette butt and cigarette ash was determined and compared using genotoxicity and phytotoxicity assessments. The concentrations of five heavy metals, As, Cr, Cd, Pb, and Ni, were determined in both cigarette butt and ash leachates to find out if the results of heavy metals are in parallel with toxicity findings. Cigarette ashes and cigarette butts were soaked in distilled water for 7 days. Six leachate butt concentrations, including 200, 100, 50, 25, 12.5, and 6.25 piece/L, were examined. HUVEC cells (human umbilical vein endothelial cells) were exposed to these dilution series for genotoxicity, and Vicia faba seeds were exposed to the same dilution series for phytotoxicity assessments. Three parameters of genotoxicity, including tail length, %DNA in tail, and tail moment, were obtained by the comet assay method, and three parameters of phytotoxicity, including germination rate, root length, and water content percentage, were employed. The results showed that cigarette ash at the concentrations of 50, 25, 12.5, and 6.25 pc/L brings about DNA damage. Meanwhile, cigarette butt causes DNA damage at the concentrations of 100, 50, 25, and 12.5 pc/L. The highest concentrations (200 pc/L for cigarette butt and 200 and 100 pc/L for cigarette ash) were considered lethal for HUVEC cells. Besides, the levels of genotoxicity in the cigarette ash were twice as high as those in the cigarette butt. The Vicia faba phytotoxicity test demonstrated a germination rate restriction from 100 to 52 and 100 to 0% for cigarette butt and cigarette ash, respectively. It also caused a reduction in the length of roots from 35 to 7.85 and 3 mm for cigarette butt and cigarette ash, respectively. The moisture amounts of cigarette remnants had a decline from 93.14 to 44.61 and 36.72% for cigarette butt and cigarette ash, respectively. Concentrations of As, Cr, Cd, Pb, and Ni were 17.45, 2.5, 0.15, 6, and 0.62 ppb in the butt leachate and 7.21, 2.64, 0.29, 13.61, and 1.24 ppb in the ash leachate, respectively, indicating that heavy metals could explain the higher toxicity of cigarette ash. Based on the present study, cigarette ash imposes not only higher levels of genotoxicity and phytotoxicity but also more values of toxic heavy metals on our planet. Thus, cigarette ash plays a major role in environmental pollution, and the importance of cigarette ashes should receive attention even more than cigarette butts. This paper casts new light on the toxic impacts of cigarette ash.

We empirically investigated the existence of a Kuznets curve for OECD area in terms of municipal solid waste generation by utilizing a panel data covering the 2002–2017 period. Results from GMM and between estimators conclude that an inverted U-shaped Kuznets relationship holds for OECD countries, but only in relative terms. Results show that consumption expenditure is one of the main drivers of waste generation. Country-based estimations of random coefficient approach state that 8 out of 16 high-income countries and only 2 out of low-income countries have achieved decoupling the waste generation from consumption expenditures. Some policy implications are recommended.

Bioleaching is suggested as a methodology with benefits in ex situ/in situ bioremediation for reducing metal contamination in dredged sediments. The process of bioleaching assisted by microorganisms in a stirred tank is widely used, among other biohydrometallurgical techniques, for the efficient extraction of metals of interest if the recovery costs of valuable metals allow it. Measurement of the mass transfer capacity of oxygen in an aerobic bioreactor is of vital importance; this factor determines the productivity of the system, since it promotes microbial growth and hence enables a bioconversion process at the mineral surface takes place. The main objective of the present research was to determine the volumetric oxygen transfer coefficient (kLₐ) during the manganese bioleaching process in a stirred tank reactor using silicone oil as a vector to improve the transfer of gaseous substrates. Experiments were carried out in triplicate with a 2² factorial design analyzing temperature (30 and 40 °C) and stirring speed (300 and 500 rpm). The effect of viscosity on the system was also determined by modifying the concentrations of mining waste (30, 40, and 50%), ferrous sulfate (FeSO₄ · 7H₂O) (2, 4, 8, and 14%), and silicone oil (0, 5, and 10%) at 0 and 24 h of mixing. The results showed an increase in the value of kLₐwith respect to time, from kLₐ₍₀ ₕ, ₃₀ °C, ₅₀₀ ᵣₚₘ₎ = 8.75 s⁻¹ to kLₐ₍₂₄ ₕ, ₄₀ °C, ₅₀₀ ᵣₚₘ₎ = 18.18 s⁻¹; ANOVA statistical analysis was performed with the Fisher and Tukey tests and showed that there were statistically significant differences.

Previous studies have shown the effect of extremely low-frequency (ELF) magnetic fields on the hematopoietic system. However, molecular modification and biological toxicity are not known yet. The aim of this study was to investigate the effect of occupational exposure to ELF magnetic field on the hemoglobin and DNA alteration using Fourier transform infrared (FTIR) spectroscopy. Twenty nine individuals were selected among those working as the controller in a powerhouse in order to be studied as the population exposed to ELF magnetic field. Control group comprised of 29 administrative employees voluntarily participated who were matched with the exposed subjects in terms of sex, age, work experiences, smoking habit, and socioeconomic status. DNA and hemoglobin were extracted from blood samples and then were studied by FTIR spectroscopy. The results showed the level of magnetic field exposure was between 0.38 to 50 μT in the exposed subjects while the level of magnetic field exposure was between 0.19 and 20 μT for the unexposed people. Hemoglobin level was equal to 15.67 ± 1.42 g/dL for exposed subjects which is significantly lower than that of the unexposed people (p = 0.0001). There was a significant alteration in CH content and COO structure of the hemoglobin structure. Moreover, DNA showed significant changes by functional group of organic base. This change in the structure of DNA and hemoglobin can lead to the creation of risks in human health. In conclusion, FTIR method could reveal the quality of DNA and hemoglobin structure in subjects after exposure to ELF magnetic field.

In the present work, biological hydroxyapatite (Bio-HAp) was generated from waste poultry bone and modified with magnesium oxide (MgO) nanoparticles (Bio-HAp/MgO) and used in the adsorption process of methyl violet (MV). The Bio-HAp and Bio-HAp/MgO mesoporous composites were characterized using physicochemical techniques. Bio-HAp and Bio-HAp/MgO composites had crystalline and mesoporous structures. The specific surface area of Bio-HAp/MgO mesoporous composites (14.7 m²/g) was higher and lower than that of Bio-HAp (4.6 m²/g) and MgO (154.9 m²/g), respectively. The effect of pH (2–10), temperature (25–45 °C), contact time (10–50 min), initial MV concentration (5–25 mg/L), and Bio-HAp/MgO quantity (0.5–2.5 g/L) on the adsorption efficiency was optimized through response surface methodology-central composite design (RSM-CCD). Among four isotherm models, the Freundlich isotherm (R² > 0.98) was better matched with the equilibrium data. Based on the isotherm parameters (E, n, and RL), the MV adsorption process using Bio-HAp particles and Bio-HAp/MgO mesoporous composites is physical and desirable. The pseudo-second-order (R² > 0.97) was more potent than the other models for modeling kinetic data. According to the thermodynamic investigation, the MV adsorption was an exothermic and spontaneous process. The mesoporous composite had good reusability to remove MV dye from liquid media up to 5 steps. Bio-HAp particles and Bio-HAp/MgO mesoporous composites were tested for treatment, which significantly reduced the dye content of the real sample.

This study assessed the contamination by toxic elements (TEs), including lead (Pb), cadmium (Cd), chromium (Cr), zinc (Zn), copper (Cu) and arsenic (As), and their accumulation characteristics in soil-crop systems in Xingren, Guizhou, southwest China, by using the target hazard quotient (THQ) to evaluate the possible health risk in the target area. The mean value of the geo-accumulation index (Igeo; 1.95, 1.89 and 1.96 for rice, maize and Coix lacryma-jobi L., respectively) shows As in partial contamination level. The potential ecological risk index (RI) values show that 90% of samples exceed in considerable ecology risk level (120 < RI> stalk > leaf > husk >edible part. Maize showed a major restriction in TE intake compared to rice and Coix lacryma-jobi L. The THQ of As was from 0 to 6.33 in all the plant samples, which indicates that the THQ exceeded the safe limit (THQ=1) in some samples. The total THQs (TTHQ) had a similar trend as RI, further indicating the potential health risk of the elements in combination. These data indicate that local people experience significant health risks if they ingest crops from the investigated area. This study assessed the contamination by toxic elements (TEs), including lead (Pb), cadmium (Cd), chromium (Cr), zinc (Zn), copper (Cu) and arsenic (As), and their accumulation characteristics in soil-crop systems in Xingren, Guizhou, southwest China, by using the target hazard quotient (THQ) to evaluate the possible health risk in the target area. The mean value of the geo-accumulation index (Igeo; 1.95, 1.89 and 1.96 for rice, maize and Coix lacryma-jobi L., respectively) shows As in partial contamination level. The potential ecological risk index (RI) values show that 90% of samples exceed in considerable ecology risk level (120 < RI> stalk > leaf > husk >edible part. Maize showed a major restriction in TE intake compared to rice and Coix lacryma-jobi L. The THQ of As was from 0 to 6.33 in all the plant samples, which indicates that the THQ exceeded the safe limit (THQ=1) in some samples. The total THQs (TTHQ) had a similar trend as RI, further indicating the potential health risk of the elements in combination. These data indicate that local people experience significant health risks if they ingest crops from the investigated area.

Extensive industrialization and urbanization have introduced domestic as well as industrial wastes into aquatic ecosystems.Dueto lack of proper treatment and improper mode of disposal, the water bodies have become more polluted with toxic substancesand their adverse effects including mortality to aquatic organisms, are becoming more prominent.In recent years, much attention has been paid to the possible danger of metal poisoning in humans as a result of consumption of contaminated fishes.Vanadium is a rare elementfound combined with certain minerals and mainly from the production of certain alloys used in jet engines. Humans may be exposed to excessive vanadium and may develop adverse vascular effects.In the present investigation, efforts have been made to investigate the effect of sublethal concentration of vanadium (6.5 ppm; 10% of 96h LC50) on the bioaccumulation in gill, liver and skin of the catfish Heteropneustes fossilis for 60 days. The pattern of bioaccumulation was in the order liver > gill > skin. Theresults suggest that the organ-specific variation is directly related to the structural and functional change, proximity to the toxicant and presence of ligands having high affinity to vanadium.

The COVID-19 pandemic is one of the biggest health calamities that the world has faced, which has infected millions of people and lead to hundreds of thousands of deaths all over the world. It has impacted the economic, social and health aspects of the countries to quite an extreme level. But an indirect positive impact can also be seen on the environment. In this paper, taking the example of Delhi, one of the most polluted cities of India, an analysis has been done to compare the levels of air pollutants (PM2.5, PM10, NOx and ozone) during the lockdown and the same period in the previous years. The study shows that the extent to which the industries, vehicles, power plants etc. release the air pollutants and severely impact the environment and human health. As during the lockdown when all such activities were either stopped or very much restricted, a reduction of almost 60% in the particulate matter pollution and up to 40% in the NOx pollution was observed while the ozone levels were reduced by 30-40% as compared to the same period during the previous two years. In the end, some suggestions have been made which can play some part to control air pollution once the lockdown is over.

The demand for mineral resources is continuously increasing due to the accelerated industrialization and urbanization progress. However, most mines in China have backward mining technology, enormous destruction and waste, too low recycling proportion, unstable mineral market, and low management efficiency. Thus, the eco-environmental safety of mines has various difficulties. Identifying the influencing factors of eco-environmental safety of mines, which are typical ecologically vulnerable areas, is important. The green development of mines is a clean production mode that will not generate any harmful effect on human social and natural environments and will be important to realizing sustainable development of mines. In this study, a retrospective analysis of considerable foreign literature on ecoenvironmental safety management of mines in developed countries was conducted. An index system of the influencing factors of eco-environmental safety of Taoshan Coal Mine in Heilongjiang Province, China was established. ISM model (Interpretative Structural Modeling) was used to analyze the influencing factors of eco-environmental safety, and corresponding countermeasures for critical factors were proposed. Results indicate that studies on resource development and utilization and environmental protection of mines in some developed countries, such as America, Australia, and the UK, have been considerably mature. The influencing factors in ISM (Interpretative Structural Modeling) can be divided into three layers, among which the completeness of institution setting for environmental protection supervision is a factor with the most significant influence on mine eco-environmental safety. Input into eco-environmental protection and ecological protection laws and systems of mines are also important factors. The study results are important in determining the most critical influencing factors of mine eco-environmental safety, innovating the new industrial development pattern featured by conservation and intensive and comprehensive utilization of mineral resources, promoting green transformation and upgrading of the mining industry, and boosting sustainable development of the mining industry and eco-environment.

The molecularly imprinted polymers (MIPs) were prepared by using the non-covalent approach. In the polymerization process, xylenol orange was used as a template (T), acrylic acid as a functional monomer (M), divinylbenzene as a cross-linker (CL) and 2,2’-azobisisobutyronitrile (AIBN) as an initiator and microemulsion as a solvent. The synthesized polymers were characterized by using FTIR and SEM micrograph. The batch binding analysis was used to evaluate the rebinding efficiency of imprinted polymers. The highest rebinding efficiency was obtained from the MIP-R2 (0.1:0.6:2, T:M:CL). The selected MIP-R2 was used for the removal of xylenol orange from the water sample and have shown removal efficiency of about 80%.