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Ciprofloxacin antibiotic that is used to cure several kinds of bacterial infections have a high solubility capacity in water. The influent of ciprofloxacin to water resources in a low concentration affect the photosynthesis of plants, transforms the morphological structure of the algae, and then disrupts the aquatic ecosystem. 75% of this compound is excreted from the body down to the wastewater which should be removed. BiFeO3, a bismuth-based semiconductor photocatalyst that is responsive to visible light, has been recently used to remove organic pollutants from water. In this study, the optimal conditions for removing ciprofloxacin from aqueous solutions by the BiFeO3 process were investigated. Effective parameters namely pH, reaction time, ciprofloxacin initial concentration, BiFeO3 dose, and temperature on ciprofloxacin removal were studied by using response surface methodology. The validity and adequacy of the proposed model was confirmed by the corresponding statistics (i.e. F-values of 14.79 and 1.67 and p-values of <0.0001 and 0.2505 for the own model and its lack of fit, respectively, R² = 0.9107, R2adjusted = 0.8492, R² predicted = 0.70, AP = 16.761). Hence the Ciprofloxacin removal efficiency reached 100% in the best condition (pH 6, initial concentration of 1 mg/L, BiFeO3 dosage of 2.5 g/L, reaction temperature of 30° C, and process time of 46 min). [ABSTRACT FROM AUTHOR]

This work reports a characterization of microplastics (MPs) and microrubbers (MRs) such as color, size, shape, and the chemical composition in snowfall in central Iran (Qom) at five sites. Identification of MPs and MRs involved using a stereo microscope to evaluate physical characteristics such as thickness, shininess, hardness, and reaction to a hot needle. HYSPLIT trajectory and end-member microplastic (PM) mixing models are used to determine the contribution of local and remote sources to MPs. The mean (±SD) abundance of MPs and MRs is 23.8 ± 15.87 (MP/L) and 1.26 ± 1.16 (MR/L), respectively, whereas the mean (±SD) abundance of MPs and MRs is 30.7 ± 19.36 (MP/m 2 ) and 1.58 ± 1.39 (MR/m 2 ), respectively. The frequency of MP colors in order are: black (63.8%) > red (12.8%) > blue (11 %) > white (9.1%) > green (2.1%) > yellow (1.3%). About 71.6% and 3.6% of the identified MPs are 250-500 μm and >1000 μm, respectively. Snow samples contain different identified polymers such as polyethylene terephthalate (PET), nylon, viscose, polypropylene (PP), polyethylene (PE), polystyrene (PS), and polyvinyl chloride (PVC). Analysis reveals that 90% of Qom city's snowy day winds come from local sources. The high MP levels in are due to human activities from local origins according to end-member MP mixing model. Further study is needed to understand the potential impacts of MPs and MRs on ecosystems and human health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Antibiotics are one of the most widely used drug groups. The presence of antibiotics in urban water sources and sewage creates many environmental and medical risks for humans and other living organisms. In this study, the potential of zinc oxide (ZnO) coated on almond shell activated carbon (ACA-ZnO) in removing ciprofloxacin (CIP) from aqueous solutions was investigated. Almond shell was used to make activated carbon. Zinc oxide nanoparticles were prepared by the sol-gel method, and finally, ZnO nanoparticles were bonded to activated carbon. The effect of independent parameters pH, contact time, adsorbent dose, and initial CIP concentration on CIP removal efficiency using ACA-ZnO was investigated by response surface methodology. Optimal removal was obtained at pH = 5.4, CIP initial concentration = 7.4 mg/L, adsorbent dose = 0.82 g/L, and reaction time = 67.3 min. This study followed a quadratic model (R 2 = 0.958). The best model of adsorption isotherm fits with the Freundlich model (R 2 = 0.9972) and the maximum capacity was 251.42 mg/g adsorption kinetics, and pseudo-second-order kinetic model (R 2 = 0.959). The results of this study showed that ACA-ZnO as an adsorbent is very efficient, without environmental side effect and cost-benefit., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The application of the coagulation/flocculation process is very important due to its simplicity in removing turbidity. Due to the disadvantages of using chemical coagulants in water and the lack of sufficient effect of natural materials alone in removing turbidity for proper performance, the simultaneous use of chemical and natural coagulants is the best way to reduce the harmful effects of chemical coagulants in water. In this study, the application of poly aluminum chloride (PAC) as a chemical coagulant and rice starch as a natural coagulant aid to remove turbidity from aqueous solutions was investigated. Effects of the above coagulants on the four main factors, coagulant dose (0-10 mg/L), coagulant adjuvant dose (0-0.1 mg/L), pH (5-9), turbidity (NTU 0-50), and each five levels were assessed using a central composite design (CCD). Under the optimized conditions, the maximum turbidity elimination efficiency was found to be 96.6%. The validity and adequacy of the proposed model (quadratic model) were confirmed by the corresponding statistics (i.e., F-value of 23.3, p-values of 0.0001, and lack of fit of 0.877 for the model, respectively, R 2  = 0.88, R 2 adj . = 0.84, R 2 pred  = 0.79, AP = 22.04)., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The global crisis caused by SARS-CoV-2 (COVID-19) affected economics, social affairs, and the environment, not to mention public health. It is estimated that near 82% of the SARS-CoV-2 genome is similar to the severe acute respiratory syndrome. The purpose of the review is to highlight how the virus is impacted by the environment and how the virus has impacted the environment. This review was based on an electronic search of the literature in the Scopus, Science Direct, and PubMed database published from December 2019 to July 2020 using combinations of the following keywords: SARS-CoV-2 transmission, COVID-19 transmission, coronavirus transmission, waterborne, wastewater, airborne, solid waste, fomites, and fecal-oral transmission. Studies suggest the thermal properties of ambient air, as well as relative humidity, may affect the transmissibility and viability of the virus. Samples taken from the wastewater collection network were detected contaminated with the novel coronavirus; consequently, there is a concern of its transmission via an urban sewer system. There are concerns about the efficacy of the wastewater treatment plant disinfection process as the last chance to inactivate the virus. Handling solid waste also requires an utmost caution as it may contain infectious masks, etc. Following the PRISMA approach, among all reviewed studies, more than 36% of them were directly or indirectly related to the indoor and outdoor environment, 16% to meteorological factors, 11% to wastewater, 14% to fomites, 8% to water, 9% to solid waste, and 6% to the secondary environment. The still growing body of literature on COVID-19 and air, suggests the importance of SARS-CoV-2 transmission via air and indoor air quality, especially during lockdown interventions. Environmental conditions are found to be a factor in transmitting the virus beyond geographical borders. Accordingly, countries need to pay extra attention to sustainable development themes and goals., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Remaining pharmaceutical compounds cause environmental pollution. Therefore, refining these compounds has become a major challenge. In this study, the function of eliminating Cefixime (CFX) using rice starch was evaluated under controlled conditions., Methods: Response Surface Methodology (RSM) was used to design, analyze, and optimize experiments, and the interaction between four variables including pH (3-9), rice starch dose (0-300 mg/L ), CFX initial concentration (0-16 mg/L ) and time (20-120 min ) was investigated on CFX removal., Results: The optimum pH, starch dose, initial concentration and time were 4.5, 225 mg/L , 7.9 mg/L and 95 min , respectively. The maximum efficiency of CFX removal was 70.22%. According to RSM, this study follows a quadratic model (R 2 =0.954)., Conclusion: Rice starch has been successful in removing CFX from the aqueous solution. Therefore, it is recommended to utilize this process to remove CFX from aqueous solutions., (Copyright© 2020 Avicenna Research Institute.)

Occupational exposure to hydrochloric acid in pickling of steel for remove rust or iron oxide scale from iron processing occurs at low concentration. This study aimed to investigate the respiratory symptoms and pulmonary dysfunction caused by exposure to low concentration of hydrochloric acid in acid washing unit in one of the steel industries. A case control study was carried out in the acid washing unit of the cold rolling of the steel industry in 2017. The exposed group included 45 male workers, and another 41 unexposed employees from official employees were enrolled as control group. A questionnaire was used to collect personal and occupational data and pulmonary function tests, including forced vital capacity (FVC), forced expiratory volume in the first second and peak expiratory flow rate followed guidelines given by the American Thoracic Society and measured with a portable calibrated vitalograph spirometer. For determination of acid concentration, 21 breathing zone air samples were collected in accordance with Method 7903 NIOSH. The findings showed that nose sensitivity, throat irritation and shortness of breath were the highest prevalence symptoms among exposed persons (30.4% to 32.6%). Also, the results showed that FVC and forced expiratory volume in the first second had highest and direct or positive correlation with height (0.965 and 0.927, respectively). Age and weight put in the next priorities (P < 0.01). On the other hand, based on the results of multivariate linear regression, exposing to the acid and job history are two main predictor factors for FVC. So that, the exposing to acid, by itself can reduce FVC as 4.386 units. This value is equal to 1.117 for the job history. Exposure to low concentrations of hydrochloric acid alone could increase the risk of respiratory tract damage and pulmonary function disorders. But the extent to which it can cause respiratory complications for occupational exposure is still unknown and requires further study. This study was approved by Ethical Committee of Qom University of Medical Sciences (approval No. IR.MUQ.REC.1397.118) on November 6, 2018.