Comparison between Removal Efficiency of Slag, zeolite, and Conventional media in slow sand Filter for Removal of Lead and Cadmium from Water Resources

Introduction: Heavy metals owing to their health hazards and high toxicity in low concentration for human and environment have very concern and attention. Slow sand filter is one of the simple and cost-effective for removal of these pollutants. In this method, media play an important role for removal of pollutant. Therefore, the aim of this study was investigation of different media like slag, zeolite, and conventional media in slow sand filter for removal of lead and cadmium. Methods: In this research there are three beds filter include typical filter bed, slag and zeolite that used in pilot plant for investigation of lead and cadmium removal at three concentration of 0.1T 1 and 10 ppm. Each of filters has an internal diameter of 8 cm and a height of 120 cm with Plexiglas, which have a continuous flow operation. Results: The removal efficiency of turbidity by three typical filter bed, slag, and zeolite with initial turbidity of 13 NTU was 46%, 77%, and 89% respectively. Removal efficiency of lead without turbidity was 70.3%, 79%, and 59.8% respectively for 0.1 ppm lead. For 1 ppm, concentration of lead removal efficiency was 51.8%, 52.7% and 52.6% respectively and for 10 ppm it was 53.4%, 57.8%, and 59.8% respectively. Cadmium removal for these media was 23.4%, 37.5%, and 59.4% respectively at 0.1 ppm cadmium. At 1 ppm of cadmium concentration, it was 37.9%, 45% and 41.3% respectively and at 10 ppm concentration of cadmium it was 68.3%, 68.6% and 67% respectively. Conclusion: Slag and zeolite beds are more efficiently than the conventional sand beds in the slow sand filter, so it can be used instead of the usual sand for removing lead and cadmium from resources water

Assessment of hospitalization and mortality from exposure to PM10 using AirQ modeling in Ilam, Iran

The aims of this study were to assess the health impact of PM10 on inhabitants and to investigate the trend of PM10 concentrations in Ilam, Iran, from 2012 to 2015. For these aims, daily average concentration of PM10 was obtained from continuous monitoring stations in the study area. Mortality and morbidity due to PM10 were assessed by AirQ software developed by World Health Organization (WHO). Based on the results, the annual mean concentrations of PM10 in all of years were more than WHO guideline and PM10 concentration had a decreasing trend in this study period. Total mortality attributed to PM10 was found to be 49 cases in 2012, 25 in 2013, and 33 in 2014. Hospital admission due to respiratory diseases was the most impact due to PM10. Increase in relative risk (RR) with every 10 mu g/m(3) increase in PM10 from 2012 to 2015 years for total mortality, respiratory disease hospitalization, and hospital admissions were 0.6, 0.8, and 0.9, respectively. The results of this study indicated that air pollution is one of the major problems in this urban area and AirQ model as simple tool can help to design preventive and controlling programs in order to reduce human health effects of pollutants

Climate change and distribution of zoonotic cutaneous leishmaniasis (ZCL) reservoir and vector species in central Iran

Aim of the study was to investigate the effects of climate change on the potential distribution of the zoonotic cutaneous leishmaniasis (ZCL) reservoir and vector to 2050s in central Iran. The bioclimatic variables (BVs) were obtained from the World Clim global climate data at a resolution of 30 s. MaxEnt software was used for the model predictions by all variables. According to the Representative Concentration Pathway 4.5 (RCP 4.5) Scenario, the area under the curve (AUC) for Rhombomys opimus and Phlebotomus papatasi was calculated as 0.877 and 0.921, respectively. Jackknife test indicated that BV2 (76.7) and BV8 (38.1) had the highest effect on the models for the reservoir and vector, respectively. In the RCP 8.5 scenario, AUC value for R. opimus and P. papatasi were obtained as 0.851 and 0.913, respectively. Jackknife test displayed that BV7 (73.5) and BV8 (34.6) were the most important variables on the model for the reservoir and vector, respectively. Future projections of models indicated that to the 2050s, the climatically suitable area for P. papatasi would expand mainly in the western area of the Yazd province, whereas would decrease in the eastern areas. Currently, the presence probability of this species in Bafq city was reported by about 70. It is projected that in the 2050s, many areas of the province would have a dramatic decline in ZCL distribution. The results of this study will help the health authorities to forecast possible future ZCL transmission dynamics in different areas of Yazd province and to make appropriate decisions in the high-risk areas. © 2020, Springer Nature Switzerland AG

Spatial analysis of heavy metals in surface soil, NW Iran

During last decade, drying of Lake Urmia and salty dust emission could be contaminated soil in northwest of Iran. This study aimed to assess the concentration and spatial analysis of toxic metals (As, Cd, Cu, Ni, Pb and Zn)in surface soils. Soil samples were taken from the top 30 cm of soil and analysed for heavy metals content using inductively coupled plasma optical emission spectrometry (ICP-OES). As results of Moran�s I model, distribution pattern for As, Cd, Cu, Ni, Pb and Zn were random (z-score ranged between �1.17 and 1.09). Indicated that these elements could be emitted from different potential sources. Spatial analysis shows that Cd, Cu, Pb, Ni, and Zn, have similar distribution trends with non-identical values which indicated that their sources could be identical. Based on degree of contamination (Cdeg) index, soil samples from north, northwest and northeast were categorised at very strong contamination degree. Finally, in northwest of Iran, drying Lake Urmia, agricultural and industry activity could be lead to soil and air pollution in terms of heavy metals. © 2020 Informa UK Limited, trading as Taylor & Francis Group

A Protocol for Pollution Index, Source Identification, and Spatial Analysis of Heavy Metals in Top Soil

Introduction: This study aimed to assess a good protocol for the contamination indexes, concentration, spatial analysis, and source identification of toxic metals in top soils. Materials and Methods: In the first step, samples were taken from top soil (30 cm) and the metals were extracted and detected with ICP-AES. In the second step, Enrichment Factor, Geoaccumulation Index, and Contamination Factor of metals were calculated to determine soil contamination degree. Furthermore, the principal component analysis and correlation between metals were conducted for source identification. Results: Spatial analysis, as an important section of the present protocol, was performed using Arc GIS, kriging, and Moran�s I models. As results of Moran�s I model showed, distribution pattern for Fe, As, Cd, Cu, Ni, Pb, and Zn were random (z-scores ranged from -1.17 to 1.09), indicatingthat these elements could be emitted from different potential sources. In Moran�s model, spatial autocorrelation of each pollutant could be measured based on its value and location. Conclusion: The finding of this protocol can be used for extraction of contamination indexes, concentration, spatial analysis, and source identification of toxic metals in top soils. © 2020. All Rights Reserved

The performance of TiO2/NaY-zeolite nanocomposite in photocatalytic degradation of Microcystin-LR from aqueous solutions: Optimization by response surface methodology (RSM)

Background: Microcystin (MC) is a hepatotoxic and carcinogenic toxin that is generated by cyanotoxins which can have adverse effects on the human health. Therefore, it is very important to remove it from the environment. This study was performed to investigate the efficiency of titanium dioxide (TiO2)/NaY-zeolite (T/N-Z) nanocomposite for removal of MC-LR under ultraviolet light. Methods: In the present study, T/N-Z nanocomposite was synthesized using the hydrothermal method. Specification of the photocatalysts was determined by the field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) spectra. The response surface methodology (RSM) was used to survey the effects of operating variables such as pH, contact time, and catalyst dose on the removal of MC-LR. The MC-LR concentration was measured by high-performance liquid chromatography (HPLC). Results: It was revealed that the increase of contact time and catalyst dose had a positive effect on enhancing the removal efficiency of MC-LR, but pH had a negative effect. Finally, the maximum MC-LR removal efficiency was 97.63, which occurred at pH = 5, contact time = 120 min, and catalyst dose = 1.2 g/L. Conclusion: In general, T/N-Z composite in aqueous solutions under the UV light can easily decompose MC-LR and it can also be proposed as an efficient composite for removal of MC-LR from contaminated water

Development and Validation of a Reversed-Phase HPLC Method for the Estimation of Zolpidem in Bulk Drug and Tablets

In the present study an isocratic reversed-phase high-performance liquid chromatography method was developed for the estimation of zolpidem in bulk drug and pharmaceutical dosage forms. The quantification was carried out on C18 columns. A mixture of acetonitrile-ammonium acetate (pH=8.0, 0.02 M) (60 : 40 v/v) was used as the mobile phase, at flow rate of 1.0 mL/min and the determination wavelength at 245 nm. The retention time of zolpidem was found to be 3–5 min. The validation of the proposed method was carried out for specificity, linearity, accuracy, precision, limit of detection, limit of quantification, and robustness. The linear dynamic range was from 2.5 to 30 μg mL−1. Regression equation was found to be y=0.1416x+0.0183 with correlation coefficient r=0.9996. The percentage recovery obtained for zolpidem was greater than 96.5%. Limit of quantification and limit of detection were found to be 2.5 μg mL−1 and 0.83 μg mL−1, respectively. The developed method can be used for routine quality control analysis of zolpidem in tablet formulations

Photocatalytic degradation of microcystin-LR using BiVO4 photocatalysts under visible light irradiation: modelling by response surface methodology (RSM)

The microcystin-LR (MC-LR) is a potentially dangerous toxin for animals and human health. So, MC-LR removal from the environment by the use of photocatalysts is recommended. Generally, traditional photocatalysts are dependent on UV light and consume high energy and also produce high heat. So, the use of photocatalysts with low-energy consumption, feasible, and reliable properties that activate in the visible light is very important. The aim of the present study was the removal of microcystin-LR (MC-LR) in visible light by synthesised bismuth vanadate (BiVO4) with the hydrothermal method. The BiVO4 characteristics were determined by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FT-IR) spectra. The Response Surface Methodology (RSM) was used to survey the effects of operating variables such as pH, contact time, and catalyst dose on MC-LR removal. The results showed that the increase of contact time and catalyst dose had a positive effect on enhancing the removal efficiency of MC-LR, but the effect of pH was negative. The maximum removal efficiency of MC-LR at pH = 5, contact time = 180 minutes and catalyst dose = 0.5 g/l was equal to 93.19. Therefore, BiVO4 as an innovative photocatalyst had a suitable effect on the MC-LR degradation under visible light. © 2020 Informa UK Limited, trading as Taylor & Francis Group