Sonochemical degradation of azithromycin in aqueous solution

Background: The presence of pharmaceutical substances and their residual in water resources is an important environmental concern. Azithromycin, an antibiotic that is used for the treatment of infectious diseases, is a pollutant agent in the wastewater. The aim of this study was to investigate azithromycin degradation in aqueous solution through ultrasonic process in the presence of zinc oxide nanoparticles as catalysts. Methods: Sonocatalytic experiments were performed at variable conditions including pH (3- 8), temperature (20-60°C), time (3-21 minutes), catalyst dosage (0.25-2 g/L), hydrogen peroxide concentration (15-100 mg/L) and initial azithromycin concentration (10-100 mg/L). Results: The optimum values for pH (3), temperature (40°C), time (15 minutes), catalyst dosage (1 g/L), H2O2 concentration (50 mg/L) and initial azithromycin concentration (20 mg/L) were determined. The highest degradation efficiency of 98.4% was achieved after 15 minutes of ultrasonic irradiation under optimum condition. Conclusion: According to the results, ultrasonic irradiation is able to degrade azithromycin. In addition, ZnO and hydroxyl radical can successfully accelerate the reaction process in the shortest possible time. Keywords: Azithromycin, Catalysis, Wastewater, Ultrasonic

Adsorption of Nickel and Chromium From Aqueous Solutions Using Copper Oxide Nanoparticles: Adsorption Isotherms, Kinetic Modeling, and Thermodynamic Studies

The research was conducted with an aim to assess the efficiency of copper oxide nanoparticles as an adsorbent to remove Ni and Cr. The effect of pH, adsorbent dosage, contact time, initial concentration of metals (Ni and Cr) on the adsorption rate was evaluated and removal of these elements from aqueous solutions was measured using Atomic Absorption Spectrum System (Conter AA700). Moreover, the kinetic and isotherm besides thermodynamic adsorption models were assessed. The highest Ni and Cr removal rate occurred at an optimal pH of 7, and an initial concentration of 30 mg/L, a time period of 30 minutes, and 1 g/L of copper oxide nanoparticles. In fact, with the increase of adsorbent dosage and contact time, the removal efficiency increased and with initial concentration increase of Ni and Cr ions, the removal efficiency reduced. The correlation coefficient of isotherm models viz. Langmuir, Freundlich, Temkin, Redlich-Peterson, and Koble-Corrigan showed that Ni and Cr adsorption via copper oxide nanoparticles better follows the Langmuir model in relation to other models. The results showed that kinetic adsorption of Ni and Cr via copper oxide nanoparticles follows the second order pseudo model with correlation coefficients above 0.99. In addition, the achieved thermodynamic constants revealed that the adsorption process of metals (i.e., Ni and Cr) via copper oxide nanoparticles was endothermic and spontaneous and the reaction enthalpy values for these metals were 17.727 and 11.862 kJ/mol, respectively. In conclusion, copper oxide nanoparticles can be used as effective and environmentally compatible adsorbents to remove Ni and Cr ions from the aqueous solutions

Evaluation of polyethylene microplastic bio-accumulation in hepatopancreas, intestine and hemolymph of freshwater crayfish, Astacus leptodactylus

Microplastics (MPs) are one of the biggest environmental problems threatening aquatic life. The accumulation of MPs in the body of aquatic animals can play a role in transferring these pollutants into the food chain. These pollutants can significantly affect the physiology of aquatic animals. In this study, the bioaccumulation capability of MPs in the body of freshwater crayfish, Astacus leptodactylus has been evaluated. For this purpose, crayfish were exposed to 0, 500, and 1000 µg L-1 of polyethylene MPs (PE-MPs) for 28 days. Then, the accumulation of MPs in hemolymph, hepatopancreas, and intestine of crabs was investigated by Fourier transform infrared spectroscopy (FTIR). Bioaccumulation of PE-MPs in the hemolymph, hepatopancreas, and intestines was observed in the crayfish exposed to PE-MPs. This study showed that FTIR is a suitable method for identifying and measuring MPs in aquatic organisms

Assessing Soil Pollution with Heavy Metals using Contamination Factor Index at Zahedan Municipal Landfill

Solid waste is one of the most important sources of soil contamination. Soil chemical contaminants such as heavy metals have created deep concern throughout the world. Heavy metals are naturally present in all soils, but soil contamination due to human activities is increasing. The accumulation of these metals in the soil eventually results in their entry into the food cycle and threaten human health and other living beings. In this study, the soil pollution of Zahedan city landfill by heavy metals was studied using contamination factor index. A total of 20 soil samples, 10 topsoil samples (up to 30 cm) and 10 depth soil samples (from a depth of 30 to 60 cm) were collected from landfill and processed for determination of element concentrations by Atomic Absorption Spectrometry and for statistical analysis, the SPSS software version 23 was used. The results showed that mean concentrations of chromium, cadmium, lead, and arsenic in topsoil were 152.48, 0.213, 54.499, and 0.344 mg/kg respectively while these concentrations for deep soil were 177.14, 0.252, 49.365, 0.414 mg/kg respectively. The contamination factor index confirmed that most of sample stations were in class of low (CF >1 and 1 15≤">  CF >3) to moderate pollution

Global investments in pandemic preparedness and COVID-19: development assistance and domestic spending on health between 1990 and 2026

Background The COVID-19 pandemic highlighted gaps in health surveillance systems, disease prevention, and treatment globally. Among the many factors that might have led to these gaps is the issue of the financing of national health systems, especially in low-income and middle-income countries (LMICs), as well as a robust global system for pandemic preparedness. We aimed to provide a comparative assessment of global health spending at the onset of the pandemic; characterise the amount of development assistance for pandemic preparedness and response disbursed in the first 2 years of the COVID-19 pandemic; and examine expectations for future health spending and put into context the expected need for investment in pandemic preparedness. Methods In this analysis of global health spending between 1990 and 2021, and prediction from 2021 to 2026, we estimated four sources of health spending: development assistance for health (DAH), government spending, out-of-pocket spending, and prepaid private spending across 204 countries and territories. We used the Organisation for Economic Co-operation and Development (OECD)'s Creditor Reporting System (CRS) and the WHO Global Health Expenditure Database (GHED) to estimate spending. We estimated development assistance for general health, COVID-19 response, and pandemic preparedness and response using a keyword search. Health spending estimates were combined with estimates of resources needed for pandemic prevention and preparedness to analyse future health spending patterns, relative to need. Findings In 2019, at the onset of the COVID-19 pandemic, US$9·2 trillion (95$7·3 trillion (95% UI 7·2–7·4) in 2019; 293·7 times the $24·8 billion (95$43·1 billion in development assistance was provided to maintain or improve health. The pandemic led to an unprecedented increase in development assistance targeted towards health; in 2020 and 2021, $1·8 billion in DAH contributions was provided towards pandemic preparedness in LMICs, and$37·8 billion was provided for the health-related COVID-19 response. Although the support for pandemic preparedness is 12·2% of the recommended target by the High-Level Independent Panel (HLIP), the support provided for the health-related COVID-19 response is 252·2% of the recommended target. Additionally, projected spending estimates suggest that between 2022 and 2026, governments in 17 (95% UI 11–21) of the 137 LMICs will observe an increase in national government health spending equivalent to an addition of 1% of GDP, as recommended by the HLIP. Interpretation There was an unprecedented scale-up in DAH in 2020 and 2021. We have a unique opportunity at this time to sustain funding for crucial global health functions, including pandemic preparedness. However, historical patterns of underfunding of pandemic preparedness suggest that deliberate effort must be made to ensure funding is maintained

In₂O₃/NIO/MOS₂ Composite as a Novel Photocatalytic towards Imatinib and 5-Fluorouracil Degradation

Photocatalysts with high efficiency in water and wastewater treatment have gained increasing attention in recent years. This study synthesized an In2O3/NiO/MoS2 composite using the hydrothermal method and characterized its crystal structure, particle size, morphology, elemental purity, and optical properties. This nanocomposite exhibits high photocatalytic activity under visible light radiation. It achieved efficiencies of 91.57% and 88.23% in decomposing Imatinib and 5-fluorouracil, respectively. The formation of heterogeneity between MoS2 and NiO enhances the photocatalytic activity, which facilitates the separation and transfer efficiency of photo-generated electron-hole pairs, increases the catalytic active sites, and inhibits the rate of electron-hole recombination. The photocatalytic mechanism shows that both O2− and H+ are reactive species for the degradation of the studied pollutant. The stability and reusability tests deposited that the In2O3/NiO/MoS2 composite photocatalyst has superior stability during four reuse cycles. The results of the study show that a unique photocatalyst system can provide a new perspective and create new opportunities for the design of efficient composite photocatalysts

Investigation of Surface Soil Contamination around the Qayen Cement Factory by Lead and Chromium

Heavy metals are a global problem; their entrance to the human food chain bring about irreparable problems. These metals are naturally occurring in rocks and soils, but the release of metals into the soil has increased through human activity over the past decade. The purpose of this study was to determine the contamination of heavy metals like, lead and chromium in the soil around the Qayen Cement Plant using the geo-accumulation index, pollution factor and pollution index. According to a systematically sampled network at eight different directions in distances of 200, 300, 400, 500, 600, 700, 800 and 1000 meters from the cement factory, totally, 64 samples were taken. Soil samples were passed through a 2-mm sieve, and then digested with hydrofluoric acid, perchloric acid, hydrochloric acid, and nitric acid then the concentration of Pb and Cr was measured using atomic absorption spectrometer (Contr AA700) through flame method. The results suggest that the average metal chromium and lead were 52.05 and 66.79 mg/kg respectively. A Geo-accumulation index value for the metal in all stations at various distances is located in classes I and II (non-polluted to little contaminate). Pollution index values indicate that the stations at various distances, the moderate pollution accounted for 39 and 44% chromium and lead, as well as high pollution as 61 and 56% of these two elements respectively. In conclusion, as the result shows the concentration of Pb and Cr are higher than control samples and are accumulating