The present investigation examined the impact of highways on the global dispersion patterns of metallic elements present in dust and snow. A total of 18 mixed snow samples were collected from both sides of the Moscow-Tambo-Astrakhan Caspian Highway by the end of the winter season. The analysis of the samples indicated the presence of 35 distinct chemical elements, where Al, Ba, Ca, Fe, K, Mg, Na, and Zn were identified as the primary contaminants. The primary area of pollution on the windward side originating from the road spans a distance of 20-40 meters, while on the leeward side, it extends to 10 meters. The data presented suggests that the metals found in highways exhibited variability in terms of their solubility in water and concentration. Our findings demonstrate that the predominant wind directions affect the dispersion of pollutants. Furthermore, it was observed that the region with a higher concentration of metal on the side of the road facing the wind had a thickness that was 2-3 times less than that of the opposite side. It is advisable to conduct a subsequent inquiry within the ensuing five years to obtain dependable data regarding the extent of metal pollution.

In this study, a multitude of statistical tools were used to examine PM10 concentration trends and their seasonal behavior from 2015 to 2021 in Tehran. The results of the integrated analysis have led to a better understanding of current PM10 trends which may be useful for future management policies. The Kruskal – Wallis test indicated the significant impact of atmospheric phenomena on the seasonal fluctuations of PM10. The seasonal decomposition of PM10 time series was conducted for better analysis of trends and seasonal oscillations. The seasonal Mann-Kendall test illustrated the significant possibility of a monotonic seasonal trend of PM10 (p = 0.026) while showing its negative slope simultaneously (Sen = -1.496). The forecasting procedure of PM10 until 2024 comprised 15 time series models which were validated by means of 8 statistical criteria. The model validation results indicated that ARIMA (0,1,2) was the most satisfactory case for predicting the future trend of PM10. This model estimated the concentration of PM10 to reach approximately 79.04 (µg/m3) by the end of 2023 with a 95% confidence interval of 51.38 – 107.42 (µg/m3). Overall, it was concluded that the use of the aforementioned analytical tools may help decision-makers gain a better insight into future forecasts of ambient airborne particulate matter.

Today, the application of supercritical fluid extraction (SFE) has been the focus of many researchers in various industries due to suitable operating conditions, environmental friendliness (no use of organic solvents) and high efficiency. In this process, a solvent is used for separation in supercritical conditions. Pharmaceutical, oil extraction, and oil and gas industries have conducted extensive research in this field. Electronic and electric devices are constantly being upgraded and updated due to the rapid advancement of science and technology, which creates a number of issues with handling electric and electronic waste (e-waste). The most significant issue is that it is challenging to safely dispose of halogen flame retardants and refractory polymers in e-waste. Supercritical fluid (SCF) techniques provide significant environmental benefits over previous disposal methods like pyrolysis and acid leaching since they pose no dangers for air or water contamination. This study discusses and provides a summary of the basic concepts and appropriate factors of supercritical fluid extraction (SFE). SCF methods were claimed to have recovered precious metals, base metals, and other inorganic minerals from e-waste with a recovery efficiency of further 93%. This study reviews the recent advances in supercritical water (SCW) and supercritical carbon dioxide (SCCO2) extraction technologies for metal recovery from e-wastes. On the other hand, hybrid technologies are significantly improving in this field which could be considered for future studies.

As natural corridors, urban rivers are often under ecological pressures disturbing their environmental functions, and services over time and space. The landscape services (LS) has been accordingly introduced as an alternative method to evaluate such functions at the landscape scale. In this regard, public perceptions can seriously shape landscape changes, with potentially consistent or inconsistent implications for ecosystem sustainability over time and space. To shed light on this issue, the present study aimed to evaluate the LS of the Mehranrood River running through the city of Tabriz, Iran, from local users' perspective. For this purpose, approximately 365 questionnaires (with the Cronbach's alpha coefficient equal to 0.97) were developed based on the LS indicators and completed by the stakeholders. To analyze the results, structural equation modeling was applied. Afterward, the accuracy of the given model was checked by applying the root-mean-square error of approximation (RMSEA). The results showed that the service provision accounted for the largest number of factors. The cultural services were completely dependent on the presence of production/supply and regulation/maintenance services. The study results demonstrated that, the river had no efficient structures and functions from the stakeholders' perspective. They even believed that the ecological restoration of the Mehranrood River could deliver the potential ability to enhance its LS. Moreover, the respondents were willing to be in close contact with the river if it could be ecologically rehabilitated. Generally, ecological restoration could help boost urban resilience over time through the regeneration of ecological infrastructure, which required a transition from mechanical to ecological thought.

This article presents that the coagulation-flocculation process is one of the water treatment processes that mainly removes dyes from aqua solution by using chemical and natural coagulants. This research was conducted to evaluate the use of chemical coagulants (ferric chloride (FeCl3), aluminum chloride (AlCl3) and natural coagulant (okra pods) to remove Vat Green 3 (VG 3) dye from aqua solution by the coagulation-flocculation process. Various experimental parameters were studied by jar test experiments such as pH, coagulant dosages, initial VG 3 dye concentration, mixing speed, and settling time. The results showed that the maximum removal efficiency of VG 3 dye was for FeCl3 97.261%, AlCl3 94.466% and okra pods 92.572% at optimum conditions pH 6 for FeCl3 and okra pods, pH 7 for AlCl3, coagulant dosage 400 mg/L for FeCl3 and AlCl3, 200 mg/L for okra pods dosage, concentration of dye 80 mg/L, mixing speed 150 rpm, and settling time 60 min for FeCl3 and AlCl3, 70 min for okra pods at room temperature 25 ± 2 oC. The maximum volume of sludge at optimum conditions was 33 mL/L, 20 mL/L, 3 mL/L for FeCl3, AlCl3, okra pods, respectively. The kinetics of the coagulation-flocculation process was obeying pseudo first order kinetics more than pseudo second order kinetics. These results indicated that the natural coagulant (okra pods) could be an alternative to chemical coagulants for removal of VG 3 dye from textile effluent due to its low cost, biodegradable, non-polluting and lower sludge production.

This article provides an overview of the main findings of a survey on the effects of ambient temperature and humidity on vehicular emissions of criteria pollutants and greenhouse gases. The present study is focused on the emissions of Carbon Monoxide (CO), Nitrogen Oxides (NOX), Sulfur Oxides (SOX), Particulate Matters (PM), Carbon Dioxide (CO2), Nitrous Oxide (N2O), and Methane (CH4) from gasoline engine passenger cars. In this analytical research, the International Vehicle Emissions (IVE) model was operated, using long-term meteorological data to determine the effects of various ambient temperature and humidity levels on exhaust pipe pollutants and greenhouse gas emissions. The results of present study indicated that as the ambient temperature increases from -7.5 °C to 20 °C, CO, NOX, and CH4 emissions decrease by 35.8%, 6.46%, and 21.44%, respectively, while SOX, PM, CO2, and N2O emissions remain constant. In contrast, increasing the ambient temperature from 20 °C to 37.5 °C increases the emissions of all the investigated pollutants and greenhouse gases. On the other hand, the findings showed that as the ambient humidity increases from 8% to 98% CO and CH4 emissions increase by 7.3% and 2.13%, respectively; while NOX emissions decrease by 16.84%. However, humidity changes did not have noticeable impact on the emissions of SOX, PM, CO2, and N2O. This study concluded that changes in meteorological parameters over a certain period of time, not only affect global warming, but also the emissions of criteria pollutants.

Cold plasma has emerged as a powerful energy-efficient and environmentally friendly advanced oxidation technique in recent decades as a non-thermal approach in a wide range of applications. It is a form of plasma that is created at low temperatures and can be used for various applications, including water treatment This study aims to determine the influence of Cold plasma treatment on endotoxin reduction in dialysis water. A lab-scale unit was built to implement the experiments and synthetic water (feed solution) was prepared with a known level of endotoxin (0.48 EU/mL). The test for Limulus amebocyte lysate was used to assess concentrations of endotoxin in treated water. The experimental results showed reduce of endotoxins in the cold plasma treatment. This type of treatment reduced the concentration of endotoxin to 0.17 ± 0.09 EU/ml. The results of the study indicated that this could be an innovation in cold plasma jet fields, with numerous applications in dialysis fluid preparation.

Biomass extracted from different plant parts can play a role as a cheap, efficient and eco-friendly adsorbent. In this research, Lantana Camara L. Stem biomass (LSB), a low-cost and useless material, was introduced as efficient biomass for divalent zinc biosorption from aqueous environments. For achieving optimal conditions in the zinc biosorption process, the experimental design was applied by the response surface methodology (RSM) based on a Box-Behnken design (BBD) model. Based on the comparison between the measured and predicted amounts, the values of R2,Radj2, and Rpred2 in the Zn(II) biosorption model were 0.9960, 0.9887 and 0.9441. The Zn(II) uptake in the experiments, BBD model-based (p-value of Lack-of-Fit term = 0.228 > 0.05), varied from 15.19% to 81.11%. The maximum analyte uptake at a LSB-to-Zn(II) ratio of 8:1, synthetic solution pH of 6.5 and residence time of 75 min was predicted at 97.12%. The maximum Z.R.% based on the validation test performed based on the optimal predicted conditions was also obtained at 94.65%, which is 2.5% different from the model's data amount, confirming the acceptable accuracy of the quadratic model. The LSB, in optimized conditions, as a low-cost biosorbent, can be a suitable candidate with acceptable potential for heavy metals biosorption from aquatic solutions.

Wastewater irrigation may introduce antibiotic residues in the soil-plant systems. This study aimed to investigate the uptake of tetracyclines by spinach and collard greens and assess associated ecological and human health risks. Synthetic wastewater spiked with 1 ppm and 10 ppm of oxytetracycline, doxycycline, and tetracycline was used to grow vegetables in a greenhouse pot experiment. The uptake and accumulation of the tetracyclines were low and residual concentrations in the soil were negligible. All the tetracyclines were detected at concentrations ranging from 1.68 to 51.41 μg/g (spinach) and 1.94–30.95 μg/g (collard greens). The accumulation rate was in a dose-response scenario with a bioconcentration factor of 6.34 mL/kg (spinach) and 2.64 mL/kg (collard greens). Oxytetracycline had the highest accumulation in leaves, followed by doxycycline and tetracycline, and the residual concentrations followed the same order. The highest residual concentration was in soils receiving 10 ppm oxytetracycline. Residual concentrations in the soil were lower than accumulated levels and exerted negligible ecological risks. Tetracyclines accumulation in spinach significantly differed between the vegetables demonstrating a subspecies difference in uptake and accumulation. Ecological risk quotient (RQ) and human health risk quotient (HQ) were below thresholds that would exert toxicity and resistance selection impacts. Although RQs and HQs are low (<0.1), this study shows that the vegetables accumulate tetracyclines from irrigation water, posing plausible human health risks to allergic individuals. Similarly, the ecological risks cannot be ignored because the synergistic and antagonistic effects of sublethal concentrations can perturb ecosystem processes.

Seismic surveys are conducted worldwide to explore for oil and gas deposits and to map subsea formations. The airguns used in these surveys emit low-frequency sound waves. Studies on zooplankton responses to airguns report a range of effects, from none to substantial mortality. A field experiment was conducted to assess mortality and naupliar body length of the calanoid copepod Acartia tonsa when exposed to the discharge of two 40-inch airguns. Nauplii were placed in plastic bags and attached to a line at a depth of 6 m. For each treatment, three bags of nauplii were exposed to one of three treatments for 2.5 h: Airgun array discharge, a boat control, or a silent control. After exposure, nauplii were kept in filtered seawater in the laboratory without food. Immediate mortality in the nauplii was approximately 14% compared to less than 4% in the silent and boat control. Similarly, there was higher mortality in the airgun exposed nauplii up to six days after exposure compared to the control treatments. Nearly all of the airgun exposed nauplii were dead after four days, while >50% of the nauplii in the control treatments were alive at six days post-exposure. There was an interaction between treatment and time on naupliar body length, indicating lower growth in the nauplii exposed to the airgun discharge (growth rates after 4 days: 1.7, 5.4, and 6.1 μm d−1 in the airgun exposed, silent control, and boat control, respectively). These experiments indicate that the output of two small airguns affected mortality and growth of the naupliar stages of Acartia tonsa in close vicinity to the array. | publishedVersion | publishedVersion