Spatial distribution and health risk of exposure to BTEX in urban area: a comparison study of different land-use types and traffic volumes.

Many previous studies have investigated BTEX concentrations in urban areas; however, the available evidence on the association of different land-use types and BTEX concentrations is still scarce. In this study, the BTEX concentrations were measured and compared in different land-use types and traffic volumes of Mashhad metropolis, Iran. Sampling was conducted in summer and winter of 2018 based on NIOSH 1501 method in six land-use types, including Residential, Commercial/official, Industrial, Greenspace, Transportation, and Tourism. The spatial autocorrelation model was used to investigate the emission pattern. The Monte Carlo simulation technique and sensitivity analysis were used to assess the health risk of exposure to BTEX compounds. The median [interquartile range (IQR)] of benzene, toluene, ethylbenzene m-xylene, o-xylene and total BTEX concentrations based on overall mean were 4 (2.23), 8.37 (4.48), 1.2 (1.46), 0.89 (2.59), 0.8 (1.73) and 17.7 (8.19) µg/m3, respectively. Benzene and toluene had clustered emission patterns (z-score > 1.96). Exposure to benzene in the study area had a carcinogenic risk for inhabitants. The concentration of BTEX compounds was significantly different based on land-use type. The maximum and minimum concentrations of BTEX were observed in Transportation and Greenspace land uses, respectively. The BTEX concentrations in summer were significantly higher than in winter, and traffic had a significant effect on BTEX concentrations. Overall, our results supported a significant relationship between land-use type and BTEX concentrations in the urban area. Moreover, ambient benzene concentration had a carcinogenic risk potential for inhabitants of study area.

Interventional Effect of Nanosilver Paint on Fungal Load of Indoor Air in a Hospital Ward.

Hospital ward environments contain various types of microorganisms, in which fungal agents are one of the main contaminants that may cause hospital-acquired infections. Regarding this, the aim of the present study was to evaluate the effect of nanosilver paint on reducing fungal contaminants of indoor air in an educational, research, and treatment center. Two rooms in the hematology ward were selected. One room was painted using usual paint (control room) and the other room was painted with paint containing nanosilver particles (experimental room). One hundred and twelve samples were collected using active (Anderson BioSampler) and passive (settle plate or open plate) air sampling techniques. The samples were incubated for 3-7 days at 35°C, and the positive fungal cultures were examined according to morphological and microscopic characteristics. Following active sampling, the mean and standard deviation of the number of colony-forming units (CFU/m3) of fungi colonies in the experimental and control rooms were 29.21 ± 17.99 and 22.50 ± 10.02 before intervention and 13.79 ± 6.20 and 31.07 ± 21.1 after intervention, respectively. Following passive sampling, the number of CFU/plate in the experimental and control rooms was 6 and 0 before and 1and 1 after intervention, respectively. The use of the nanosilver paint was effective in reducing air fungal contamination. Moreover, the active sampling method was more sensitive to measuring the concentration changes for fungal bioaerosols.

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.

Assessing the risks associated with indoor and outdoor air quality in relation to the geographic placement of nursing home.

Indoor air quality significantly impacts the well-being and health of elderly residents in nursing homes. This study was conducted to explore the connection between indoor and outdoor PM (Particulate Matter) concentrations in nursing homes and their association with the facilities' location and construction characteristics. The findings revealed that indoor PM2.5 and PM10 concentrations ranged from 0.2 to 124 µg/m3 and 2-188.4 µg/m3, respectively, which were approximately 12.67 and 1.25 times higher than their outdoor counterparts. A strong correlation (P < 0.05) was identified between indoor PM levels and various factors, including proximity to parks, passenger terminals, and gas stations, as well as building attributes such as single-glazed windows, ceramic floor coverings, and the use of radiators. The risk assessment indicated that carcinogenic risk factors were well within acceptable limits for all nursing homes. However, it's important to note that certain PM components, particularly polycyclic aromatic hydrocarbons (PAH), may have long-term adverse effects on the health of nursing home residents. Even though indoor PM levels met the standards established by the U.S. Environmental Protection Agency (USEPA) for particulate matter risk assessments, the study emphasized that even low levels of indoor air pollutants can affect the health and well-being of older adults, particularly considering the increased vulnerability associated with aging. Consequently, the study underscores the importance of nursing home location selection and the regular monitoring of particulate matter concentrations. These measures are essential for enhancing air quality within nursing homes, ultimately contributing to the improved well-being and health of their residents.

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.

Valorization of biomass into amine- functionalized bio graphene for efficient ciprofloxacin adsorption in water-modeling and optimization study.

A green synthesis approach was conducted to prepare amine-functionalized bio-graphene (AFBG) as an efficient and low cost adsorbent that can be obtained from agricultural wastes. In this study, bio-graphene was successfully used to remove Ciprofloxacin (CIP) from synthetic solutions. The efficacy of adsorbent as a function of operating variables (i.e. pH, time, AFBG dose and CIP concentration) was described by a polynomial model. A optimal99.3% experimental removal was achieved by adjusting the mixing time, AFBG dose, pH and CIP concentration to 58.16, 0.99, 7.47, and 52.9, respectively. Kinetic model revealed that CIP diffusion into the internal layers of AFBG controls the rate of the process. Furthermore, the sorption process was in monolayer with a maximum monolayer capacity of 172.6 mg/g. Adsorption also found to be favored under higher CIP concentrations. The thermodynamic parameters (ΔG°<0, ΔH°>0, and ΔS°>0) demonstrated that the process is endothermic and spontaneous in nature. The regeneration study showed that the AFBG could simply regenerated without significant lost in adsorption capacity.

Survey of wastes management status of Khayyam industrial estate in Neyshabur City (Northeastern Iran) in 2017.

The extent of environmental pollution caused by wastes in industrial estates has attracted the attention of scientific and executive resources of the world to the correct disposal and recycling of these materials. This study is a cross-sectional descriptive study which was conducted in the Khayyam industrial estate of Neyshabur in 2017. To survey the management of industrial wastes status, based on the fieldwork, different days were selected in each week to complete the questionnaire designed by the Iranian Environmental Protection Agency. The completion of questionnaires was started from a specific path daily. Finally, the collected data were entered into the SPSS 18 software and were analyzed to determine the wastes management status of the industrial estate. Excel software was used to draw the charts. The total industrial wastes produced in Khayyam industrial estate were 3555 tons per year, waste per capita was 2177.9 g per day per worker. Most existing industries in Khayyam industrial estate were food and pharmaceutical, which include 43.94%. Recycling (79.55%) and burial (14.39%) were the first and second levels of final disposal of industrial wastes. The results of this study show that the wastes management of Khayyam industrial estate has a relatively acceptable situation. Unfortunately, the waste dumping in the open space can lead to the generation of moisture and the release of pollutants to the environment and cause pollution of water and soil through leakage as well as damage to workers. Proper control and correct management are essential for maintaining the health and protection of the environment.

Data on trend changes of drinking groundwater resources quality in Sabzevar city (A case study).

The data of this study was conducted to evaluate the groundwater quality trend changes in Sabzevar (Iran, Khorasan Razavi) during one decade (2006-2016). The Mean ±â€¯SD of electrical conductivity (as µmhos/cm), total hardness (as calcium carbonate, mg/l) and total dissolved solid in the first and end year of the study were 605.45 ±â€¯194.69 and 695.22 ±â€¯288.52, 198.77 ±â€¯56.83 and 214.45 ±â€¯84.73, 350.25 ±â€¯106.81 and 486.44 ±â€¯183.52 respectively. At the end of the results were compared with WHO (World Health Organization) guideline and Iranian drinking water standard (No. 1053). The results show that all of the evaluated parameters were less than the WHO guideline and the Iranian drinking water standard, only the TH (Total Hardness) was higher than the standard range. On the basis of Pearson correlation coefficient, the ascending trend of some parameters concentration with time was significant at the level of 95% of confidence limits (α ≤ 0.05).

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.