Detection of SARS-CoV-2 in the indoor air and surfaces of subway trains in Mashhad, Iran

INTRODUCTION

Millions of passengers around the world are concerned with the possibility of SARS-CoV-2 contamination on public transportation. Therefore, this study aimed to investigate the presence of SARS-CoV-2 virus in indoor air and subway surfaces in Mashhad.

METHODS

In this study, air and surface sampling were done at two times in the morning (7-8:30 a.m.) and evening (3:30-5 p.m.), simultaneously in two wagons for men and women in line 1 of Mashhad Metro in March 2021 to detect the virus and measure the concentration of particulate matter. Totally, 30 air and 30 metro samples were collected and examined by reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

The results showed that three and two cases in the air and surface samples were infected with the SARS-CoV-2 virus, respectively. There was a significant relationship between the mean concentration of suspended particles PM1 (particulate matter smaller than 1 μm) with PM2.5 (particulate matter smaller than 2.5 μm) and PM10 (particulate matter smaller than 10 μm) (p < 0. 05). There was also a significant relationship between the mean concentration of suspended particles PM2.5 and PM10. The results showed that the mean PM2.5 measured in the indoor air of the Mashhad metro wagon had a significant relationship with WHO and US EPA and national standards, and its value was higher than the standards (p < 0.05). The average particle concentrations of PM1, PM2.5, and PM10 were equal to 40.46, 42.61, and 48.31 μg/m3.

CONCLUSION

According to the results of the pollution detected in this study, COVID-19 may be transmitted by air and environmental surfaces. Our study emphasizes the need for continuous assessment of the presence of the virus in public transportation. Detection of viral RNA in subways indicates the necessity of adequate disinfection in public settings, strictness in disinfection methods, strengthening of educational activities for sanitary measures, physical spacing plan, and increasing ventilation of wagons.

Effects of Educational Intervention on Promoting Preventive Behaviors of Cardiovascular Disease Using the Health Belief Model in Oil Regions Workers

Background: Research conducted on oil region workers has shown that numerous ranges of physical stressors together with behavioral patterns can affect the enhancement of cardiovascular disease (CVD). The aim of this study was to investigate the effects of educational intervention to promote the preventive behaviors of CVD using the Health Belief Model (HBM). Methods: The participant of this quasi-experimental study included 228 workers (114 control and 114 experimental cases) working in oil regions. Data were collected through questionnaires containing demographic information, knowledge, and constructs of HBM. The experimental group received an education with WhatsApp. Workers completed the questionnaires before and after the education and the 3-month follow-up. Data were analyzed using SPSS 24.0. Results: The t test analyses showed no significant differences between the control and experimental groups at baseline. The results indicated the changes in outcome variables across time for groups. Except for perceived severity and perceived barriers, there were significant interaction effects between the time and group. A significant correlation was found between behavior and health belief subscales and knowledge, except for perceived severity and cues to action. Conclusion: The findings of this research confirmed the usefulness of the educational intervention based on the HBM and the necessity to apply designed programs to improve preventive behavior adoption. Preventive education with attention to decreasing unhealthy lifestyles must be designed based on the requirements and target group characteristics to prevent CVD risks.

Predicting preventive behaviors of cardiovascular disease among oil industry workers based on health belief model

BACKGROUND

Working conditions play a significant role in the process that causes cardiovascular disease. In this regard, it is required to monitor the health conditions of workers to design proper interventions to encourage healthy behaviors. This investigation was performed to determine preventive behaviors against cardiovascular disease based on the health belief model (HBM).

MATERIALS AND METHODS

This research was a cross-sectional and descriptive study with 228 subjects of oil industry workers under shift work schedules in the oil regions of Khuzestan, Iran. The HBM questionnaire provided the theoretical framework for this study. Participants completed the questionnaires in person at work. Data were analyzed using SPSS 24.0. Descriptive statistics including frequencies, percentages, and means, and linear regression analysis were calculated for variables.

RESULTS

Findings of the study showed that most workers were of a weak level of knowledge (55.3%), self-efficacy (82.5%), perceived severity (83.8%), perceived susceptibility (75.4%), perceived benefit (57.5%), and behavior (82.5%). Furthermore, results showed that most of the workers considered smoking (3.51 out of 5) and proper diet for good heart function (2.54 out of 5). In this study, the item of exercise was the lowest among all the preventive behaviors (1.39 out of 5). Self-efficacy was the strongest predictor of health belief about cardiovascular disease.

CONCLUSION

To decrease the increasing burden of cardiovascular disease in our population, and fight against this rank-one killer, multiple useful prevention strategies must be adopted. Educational theory-based interventions and applying designed programs to improve the adoption of preventive behaviors are a necessity.

The lost productivity cost of absenteeism due to COVID-19 in health care workers in Iran: a case study in the hospitals of Mashhad University of Medical Sciences

Background

Human resources management plays an important role in social development and economic growth. Absence from work due to health problems can make obstacles to the growth of economy. This study conducted aimed to estimate the absenteeism costs of COVID-19 among the personnel of hospitals affiliated to Mashhad University of Medical Sciences in Mashhad, Iran.

Methods

This cross-sectional study was conducted between February 19, 2020, and September 21, 2020. The absenteeism costs were calculated using the human capital approach. Finally, we applied the linear regression to assess the impact of variables on the lost productivity of absenteeism due to COVID-19 among the personnel of hospitals affiliated to Mashhad University of Medical Sciences.

Results

The results of this study showed that 1958 personnel had COVID-19. The total of absenteeism days in our study were 32,209 days, with an average of 16.44 absenteeism days. Total costs due to absenteeism were estimated to be nearly $1.3 million, with an average of $671.4 per patient. The results of regression model showed that gender (male), age (> 50 years), employment Type (non-permanent) and monthly income had a positive relationship with the absenteeism cost. Also, there are a negative significant relationship between absenteeism cost with job (physicians) and work experience.

Conclusions

Absenteeism costs of COVID-19 in the hospitals of Mashhad University of Medical Sciences represent a significant economic burden. The findings of our study emphasize the emergency strategies to prevent and control COVID-19 among the healthcare workers. It can decrease the economic impacts of COVID-19 and improve human resources management during the COVID-19 pandemic.

Application of artificial neural network and multiple linear regression in modeling nutrient recovery in vermicompost under different conditions

Vermicomposting is one of the best technologies for nutrient recovery from solid waste. This study aims to assess the efficiency of Artificial Neural Network (ANN) and Multiple Linear Regression (MLR) models in predicting nutrient recovery from solid waste under different vermicompost treatments. Seven chemical and biological indices were studied as input variables to predict total nitrogen (TN) and total phosphorus (TP) recovery. The developed ANN and MLR models were compared by statistical analysis including R-squared (R²), Adjusted-R², Root Mean Square Error and Absolute Average Deviation. The results showed that vermicomposting increased TN and TP proportions in final products by 1.5 and 16 times. The ANN models provided better prediction for TN and TP with R² of 0.9983 and 0.9991 respectively, compared with MLR models with R² of 0.834 and 0.729. TN and C/N ratio were key factors for TP and TN prediction by ANN with percentages of 17.76 and 18.33.

Enhanced Kinetic Removal of Ciprofloxacin onto Metal-Organic Frameworks by Sonication, Process Optimization and Metal Leaching Study

Metal-organic frameworks (MOFs) are currently recognized as unique platforms for environmental studies. This study evaluated the potential of nine MOFs from ZIF-8, ZIF-67, and UIO-66 families for the removal of ciprofloxacin (CIP), a toxic, bio-accumulative, and persistent fluoroquinolone antibiotic. ZIF-67-SO₄, with a rhombic crystalline morphology and 1375 m²/g BET surface area, has the highest CIP adsorption efficiency among the studied MOFs. The mathematical sorption model predicted that the highest CIP removal (99.2%) occurs when adsorbent dose, pH, and agitation time are adjusted to 6.82, 832.4 mg/L, and 39.95 min, respectively. Further studies revealed that the CIP adsorbed onto ZIF-67-SO₄ in monolayer (q_max: 2537.5 mg/g) and chemisorption controlled the rate of the process. Mass transfer kinetic coefficients improved significantly by sonication at 35 KHz in comparison with mechanical agitation. Thermodynamic parameters (minus signs of ∆G° [7.8 to 14.2], positive signs of ∆H° (58.9 KJ/mol), and ∆S° (0.23 KJ/mol·K)) demonstrated the spontaneous, endothermic, and chemical sorption of CIP. The level of cobalt leached from ZIF-67-SO₄ structure varied 1.2–4.5 mg/L, depending on pH, mixing time, and agitation type. In conclusion, the excellent adsorption properties of ZIF-67-SO₄ for CIP, made it an outstanding candidate for environmental protection purposes.

Enhancing photo-degradation of ciprofloxacin using simultaneous usage of eaq- and OH over UV/ZnO/I- process: Efficiency, kinetics, pathways, and mechanisms

The aim of this study is to develop the process relies on the UV irradiation of ZnO and I^-, i.e. UV/ZnO /I^- (UZI), to create both oxidizer and reducer agents simultaneously for photo-degradation of the Ciprofloxacin (CIP). This paper shows that while applying UV irradiation, UV/ZnO and UV/I^- for 20 min can lead to achieve 37.5%, 58.12%, and 61.4% photo-degradation of 100 mg L^-1 CIP at pH 7, respectively. Moreover, the UZI treatment can provide 91.54% photo-degradation efficiency. The LC-MS analysis of the UZI effluent indicates that 10 min process was adequate to degrade CIP into simple ring-shaped metabolites while 15 min treatment, mostly of CIP intermediates were linear and biodegradable organic compounds. Furthermore, fourteen little fragments were identified in the CIP photo-degradation via UZI, during the photoreaction time of 2.5 to 20 min. Then, a pseudo first-order kinetics equation was utilized to model the observed photo-degradation process. Finally, the computational results show that the increased concentration of the CIP solution from 100 to 400 mg L^-1 decreases the observed rate constant (k_obs) from 0.4125 to 0.2189 min^-1 while increases the photoreaction rate (r_obs) from 41.25 to 87.56 mg L^-1 min^-1.

Naegleria species population found in pond water of parks in Mashhad city, Can the physicochemical factors affect it?

Naegleria species are the ubiquitous free-living amoebas that are found worldwide in soil and water. Among Naegleria spp., N. fowleri can cause primary amebic meningoencephalitis (PAM). Ninety water samples were collected from the pond of parks. Also, the water quality parameters were measured at the sampling site (such as temperature, pH, total dissolved solids (TDS), electrical conductivity (EC) and Turbidity).

After filtering, the samples were cultured on Bacto-agar enriched with Escherichia coli. A PCR assay was conducted on the culture-positive samples in the ITS1, 5.8SrDNA and ITS2 regions, and then the PCR products were sequenced.

The pond water of parks was contaminated with some Naegleria spp. (except N. fowleri) and a Vahlkampfia avara. There was no significant relationship between water quality parameters and the presence of Naegleria (p > 0.05).

Our protocol investigates to detect Naegleria spp. from ponds water of parks in Mashhad city and the relations between the water quality parameters and its presence.

Isolation and identification of Acanthamoeba from pond water of parks in a tropical and subtropical region in the Middle East, and its relation with physicochemical parameters

Background

Free-living amoeba (FLA) are wide-spread protozoa that are found in different environmental sources including water, soil, dust, hospital units and ventilation areas. These amoebas can act as opportunistic or non-opportunistic pathogens. Among FLAs, some genera such as Acanthamoeba are important because of their potential pathogenic ability in humans. The purpose of this study is to identify of Acanthamoeba isolated from pond water of parks in a tropical and subtropical region in the Middle East, and its relation with physicochemical parameters.From August to December 2015, 90 samples were collected from pond water of parks of 13 regions of Mashhad City. Physicochemical parameters were measured in situ. After filtering, the samples were cultured on Bacto-agar enriched with Escherichia coli. PCR analysis was conducted on the culture-positive samples, and then the PCR products were sequenced. Statistical analysis was performed by SPSS software and Fisher’s Exact and Mann-Whitney test.

Results

Among the samples that were examined, 19 samples (21.1%) were positive for Acanthamoeba. The sequencing revealed that Acanthamoeba isolates belonged to T4 genotype of Acanthamoeba. There was no significant relationship between physicochemical parameters and the presence of Acanthamoeba.

Conclusion

The prevalence of Acanthamoeba in pond water of parks was relatively high, but there was no significant relationship between physicochemical parameters and the presence of Acanthamoeba.

Data on assessment of physical, chemical and biological characteristics of effluent from wastewater treatment in Torbat Heydarieh, Iran

Data on the chemical, physical and biological of effluent from wastewater treatment are provided in table format in the current article. Samples were taken in Peak Flows at effluent Treatment Plants. Sampling and tests were conducted according to the standards methods. The collected data were analyzed by SPSS software and excel program. Nickel metal showed higher amounts than the standards required for irrigation agricultural land. Data could be useful from environmental and agricultural sciences to those concerned about heavy metals, Alkalinity, EC, COD, BOD₅ and Microbial concentrations threats.

Data on fluoride concentration and health risk assessment of drinking water in Khorasan Razavi province, Iran

While fluoride (F) is an essential anion to keep the human body healthy, high F intake could lead to serious health problems. The monitoring of F in drinking water as the main route of F intake, is a key factor in preventing its negative health consequences. Here, we present the F levels in drinking water distribution networks of Khorasan Razavi province in Iran which collected during 2016-2017. The non-cancer human risk attributed to F in municipal and rural regions, also, estimated by calculating the chronic daily intake (CDI) and hazard quotient (HQ) for adults and children. Samples taken from drinking water distribution network in 112 different locations across the Khorasan Razavi and the F concentration determined using standard SPADNS Method. Having a minimum of 0.09 and 0.16 and a maximum of 1.7 and 1.1 mg L^-1, the mean F level in municipal and rural samples were 0.74 and 0.59 mg L^-1, respectively. The mean CDI values for F in municipal samples were 1.3×10^-2, 3.34×10^-4, and 8.56×10^-6 mg kg^-1day^-1, for men, women, and children, respectively. The CDI for rural samples were 1.51×10^-2, 3.88×10^-4, and 9.96×10^-6 mg kg^-1day^-1, for men, women, and children, respectively. The mean HQ of F for men, women, and children in municipal and rural samples were 2.17×10^-1, 5.56×10^-3, and 1.43×10^-4, and 2.44×10^-1, 6.26×10^-3 and 1.61×10^-4, respectively. Locations with a HQ>1, needs appropriate strategies for reducing the F level in drinking water to prevent the potential health risks.

Phenol removal from aqueous solution using Citrullus colocynthis waste ash

Phenol is a hazardous organic chemical that introduced into the environment by industrial and pharmaceutical discharges. As a versatile option for phenol removal, adsorption would be viable if it accompanying with low cost adsorbents. This article described a natural, very cheap and local available adsorbent for phenol removal. Phenol showed a high affinity to Citrullus colocynthis waste ash which mainly composed of SiO₂ (41.6%), Al₂O₃ (17.3%) and MgO (15.9%). Up to 70% of phenol adsorbed in the first 30 min of agitation. The phenol removal was increased by increasing adsorbent dose (0.5-10 g/L) and decreasing pH (2-12) and pollutant concentration (10-100 mg/L). The positive value of ∆H° in thermodynamic data (0.06) revealed that the process is endothermic. The high and positive value of ∆S° (13.01) and negative values of ∆G° (- 5.36 to - 7.28), showed a high affinity of phenol to the adsorbent and the spontaneous nature of the adsorption. Isotherm modelling revealed that the phenol molecules adsorbed in multilayer with the maximum adsorption capacity of 173.2 mg/g. The rate limiting step in the sorption process was chemisorption, based on the kinetic data.

Optimization of non-thermal plasma efficiency in the simultaneous elimination of benzene, toluene, ethyl-benzene, and xylene from polluted airstreams using response surface methodology

Treatment with a non-thermal plasma (NTP) is a new and effective technology applied recently for conversion of gases for air pollution control. This research was initiated to optimize the efficient application of the NTP process in benzene, toluene, ethyl-benzene, and xylene (BTEX) removal. The effects of four variables including temperature, initial BTEX concentration, voltage, and flow rate on the BTEX elimination efficiency were investigated using response surface methodology (RSM). The constructed model was evaluated by analysis of variance (ANOVA). The model goodness-of-fit and statistical significance was assessed using determination coefficients (R ² and R ²_adj) and the F-test. The results revealed that the R ² proportion was greater than 0.96 for BTEX removal efficiency. The statistical analysis demonstrated that the BTEX removal efficiency was significantly correlated with the temperature, BTEX concentration, voltage, and flow rate. Voltage was the most influential variable affecting the dependent variable as it exerted a significant effect (p < 0.0001) on the response variable. According to the achieved results, NTP can be applied as a progressive, cost-effective, and practical process for treatment of airstreams polluted with BTEX in conditions of low residence time and high concentrations of pollutants.

Decolorization of synthetic textile wastewater using electrochemical cell divided by cellulosic separator

BACKGROUND

Annually, large quantities of dyes are produced and consumed in different industries. The discharge of highly colored textile effluents to the aquatic environments causes serious health problems in living organisms. This paper investigates the performance of each of the electro-oxidation and electro-reduction pathways in the removal of reactive red 120 (RR120) from synthetic textile effluents using a novel electrochemical reactor.

METHODS

In the current study, a two-compartment reactor divided by cellulosic separator was applied in batch mode using graphite anodes and stainless steel cathodes. Central Composite Design was used to design the experiments and find the optimal conditions. The operational parameters were initial dye concentration (100-500 mg L^-1), sodium chloride concentration (2500-12,500 mg L^-1), electrolysis time (7.5-37.5 min), and current intensity (0.06-0.3 A).

RESULTS

The results showed that electro-oxidation was much more efficient than electro-reduction in the removal of RR120. According to the developed models, current intensity was the most effective factor on the electro-oxidation of RR120 as well as in power consumption (Coefficients of 12.06 and 0.73, respectively). With regard to the dye removal through electro-reduction, electrolysis time (coefficient of 8.05) was the most influential factor. Under optimal conditions (RR120 = 200 mg.L^-1, NaCl = 7914.29 mg.L^-1, current intensity = 0.12 A, and reaction time = 30 min), the dye was removed as 99.44 and 32.38% via electro-oxidation and electro-reduction mechanisms, respectively, with consuming only 1.21 kwhm^-3 of electrical energy.

CONCLUSIONS

According to the results, electro-oxidation using graphite anodes in a cell divided by cellulosic separator is very efficient, compared to electro-reduction, in the removal of RR120 from aqueous solutions.

Optimization of copper removal from aqueous solutions in a continuous electrochemical cell divided by cellulosic separator

Copper, as an inseparable part of many industrial discharges, threatens both public and environmental health. In this work, an electrochemical cell utilizing a cellulosic separator was used to evaluate Cu removal using graphite anodes and stainless steel cathodes in a continuous-flow mode reactor. In the experimental matrix, Cu concentration (1-5 mg L^-1), electrolysis time (20-90 min), and current intensity (0.1-0.4 A) were employed. Results showed that the maximum removal efficiency of copper was obtained as 99%. The removal efficiency was independent of initial copper concentration and directly related to electrolysis time and current intensity. Energy consumption was more dependent on current intensity than electrolysis time. Under optimal conditions (75.8 min electrolysis time, 0.18 A current intensity, and 3 mg L^-1 copper concentration), the removal efficiency was obtained as 91% while 7.05 kWh m^-3 electrical energy was consumed. The differences between the actual and predicted data under optimal conditions were 0.42% for copper removal and 0.23% for energy consumption, which signify the performance and reliability of the developed models. The results exhibited the suitability of the electrochemical reduction for copper removal from aqueous solutions, which was facilitated under alkaline conditions prevailing in the cathodic compartment due to applying a cell divided by a cellulosic separator.

Waste recycling by vermicomposting: Maturity and quality assessment via dehydrogenase enzyme activity, lignin, water soluble carbon, nitrogen, phosphorous and other indicators

Present study aims to examine the dynamics of maturation and qualification indicators in various vermicompost treatments and selection of the best treatment along with best maturation time in this regard. In this empirical study, dynamics of chemical (pH, electrical conductivity (EC), total nitrogen (TN), phosphorous, lignin, water soluble carbon (WSC), C/N, NH4/NO3) and biological (dehydrogenase enzyme (DEH) and DEH/WSC) properties were investigated in four various treatments, including various ratios of compost produced from municipal solid waste (MSW) and carbonaceous materials (50:50, 70:30, 85:15 and 100:0) over 100 days. Results showed a significant fluctuation in EC, DEH and DEH/WSC proportions over the process. In addition, a noticeable increase was observed for the dynamics of TN, phosphorous and lignin. In contrast, the C/N, NH4/NO3 and WSC values gradually decreased during the process. Moreover, it was observed that the length of 75 days for the process is an appropriate time for maturation of all treatments. However, the first and second treatments resulted in better outcomes compared with the other types of treatments. From the point of view of quality obtained vermicompost was nitrogen enriched product in all treatments. Whereas, for the phosphorous elements this method is appropriate for the first treatment only.

Determination of carbon/nitrogen ratio and heavy metals in bulking agents used for sewage composting

Improving the soil quality with organic matter and N, P and K contents are some of sewage sludge benefits. Adjusting carbonaceous materials such as plant wastes to dewatered sludge compost results in increasing the moisture content and improving C/N ratio. This study was conduced for three months in 2005, in Laboratory of Chemistry of Water and Wastewater in the School of Public Health of Isfahan University of Medical Science, to determine the C/N ratio and heavy metals concentration of bulking agents in sawdust, leaves, rice hulls and dewatered sewage sludge. Dewatered sludge was collected from Isfahan sewage treatment plant. Sawdust was collected from sawmills. Leaves were collected from municipality of Isfahan and rice hull from rice mills, then in samples determined C/N ratio and heavy metal according to standard methods. The results showed that concentrations of chromium and cadmium in the mixture of dewatered sewage sludge and bulking agents were lower them those of the standard level. Means of cobalt (115.44 mg kg(-1)), nickel (57.44 mg kg(-1)) and zinc (273.48 mg kg(-1)) concentrations were maximum in dewatered sludge but mean concentration of cobalt (25.66 mg kg(-1)) in rice hull samples and mean zinc (8.99 mg kg(-1)) and nickel (5.106 mg kg(-1)) concentrations in sawdust samples were minimum. The optimal conditions sewage sludge composting, each kilogram of sludge needs 350 g of saw dust, 470 g of leaves and 388 g of rice hull. Amount of heavy metals present in the bulking agents is lower than the amount mentioned for the compost.

Combined compost and vermicomposting process in the treatment and bioconversion of sludge

Traditional thermophillic composting is commonly for treatment of sludge. A related technique as vermicomposting process, using earthworms to breakdown sludge, is also becoming popular. These two techniques have their inherent advantages and disadvantages. The combined approach suggested in this study to enhance the overall process and improve the products qualities. Two systems, vermicomposting and combined compost-vermicomposting processes, have been investigated in this study. The sludge used in this study was obtained from the drying beds of South Isfahan wastewater treatment plant. The sludge mixed with sawdust to provide C/N ratio of 25/1. Eisenia fetida was the species of earthworms used in the vermicomposting processes. The results obtained indicate reduction in the amount of volatile solids, total carbon and C/N ratio with the vermicompost age, which indicates the reduction in the biodegradable organic content and mineralization of sludge. Also increase in phosphorus concentration by the end process because of mineralization of organic matter. The results indicate that, a system that combines the two mentioned processes not only shortens stabilization time, but also improves the products quality. Combining the two systems resulted in a product that was more stable and homogenous; the product could meet the pathogen reduction requirements.