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1.
Environ Sci Pollut Res Int ; 27(28): 34823-34839, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32632696

ABSTRACT

Carwash wastewater (CWW) is considered as an important source of either water pollution or water consumption. Therefore, its treatment is critical not only from the prevention of environmental contamination but also from the recycling of such high-volume water source. Unfortunately, the effective treatment of CWW is almost unknown, complex, and expensive. To overcome the former challenge, this study aimed to systematically review different technologies for CWW treatment. For this, a comprehensive literature survey was conducted and 48 research articles were found suitable to be included in the investigation. The included studies were of coagulation and adsorption (n = 5), membrane-based technologies (n = 15), and electrochemical (n = 11) and combined (n = 17) systems. This comprehensive review showed that the treatment methods of advanced filtration membrane techniques, electrical and chemical coagulation, and advanced oxidation processes can be effective in the removal of pollutants from carwash wastewater (CWW). The mining of different studies, however, showed that the combined methods are the most promising option in the remediation of such wastewater.


Subject(s)
Water Pollutants, Chemical , Water Purification , Adsorption , Oxidation-Reduction , Wastewater/analysis
2.
J Environ Health Sci Eng ; 18(1): 345-354, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32399245

ABSTRACT

PURPOSE: Open flames of gas and charcoal can induce polycyclic aromatic hydrocarbons (PAHs) in cooked meat. The current study aimed to compare the effect of gas and charcoal open flames on the induction of PAHs in cooked meat using a meta-analysis approach. METHODS: A systematic review of the literature was conducted electronically based on the PRISMA guidelines. Experimental studies comparing the PAHs content of cooked meat over open flames of gas and charcoal were searched using the appropriate keywords until June 2018. RESULTS: Of 1137 papers retrieved, 7 with a total sample size of 474 meat samples were used in the meta-analysis. The mean difference (MD) between the gas and charcoal cooking methods in the induction of each PAH was 2.053 µg/Kg. (95%CI: 1.022-3.085 µg/Kg; P < 0.001). The subgroup analysis of 17 trials indicated the difference between the two cooking methods increases when red meat rather than white meat is cooked (MD in red meat: 3.499 µg/Kg; 95%CI: 2.030-4.967; P < 0.0001 vs. MD in white meat: 3.319 µg/Kg; 95% CI: 1.689-4.950; P < 0.0001). Interestingly, studies that analyzed meat samples for fewer PAHs (cut-off ≤7) found a much wider difference between gas and charcoal-cooked meat (MD: 5.106 µg/Kg; (95% CI: 2.162-8.049; P < 0.001 in studies with ≤7 PAHs vs. MD: 1.447 µg/Kg; 95% CI: 0.628-2.266; P < 0.001 in studies with >7 PAHs). CONCLUSIONS: It is necessary to avoid open flames of charcoal as the heat source or change the geometry of charcoal-fired cookstoves to prevent fat dripping on the fire and thus, excessive PAHs induction.

3.
Environ Geochem Health ; 42(5): 1305-1319, 2020 May.
Article in English | MEDLINE | ID: mdl-31564015

ABSTRACT

Groundwater is a precious natural water resource which can be considered as an available and safe source of water for domestic uses. In some cities in northern Iran, groundwater is being polluted due to various human activities. In this regard, the located municipal solid waste landfills close to these areas without the requested controls regarding the landfill leachate and gas emission are among the major sources of environmental pollution, which are deteriorating groundwater quality around landfill sites. In this context, the current study was aimed to assess the quality of collected groundwater samples around a landfill site using the modified Water Quality Index for groundwater resources (WQIG). Also, the water quality map has been prepared by using WQIG in GIS environment. Therefore, thirty-three groundwater samples were collected and analyzed around 11 water wells close to the landfill site. Variety of physicochemical parameters including nitrate (NO3), fecal coliform, sodium absorption ratio (SAR), electrical conductivity, biological oxygen demand (BOD5), phosphate (PO4), total dissolved solids, dissolved oxygen, pH were assessed in groundwater samples based on recommended standard methods by American Public Health Association (APHA). Geostatistics analysis including Kriging, semi-variogram, and variogram methods also was used to evaluate the spatial variations in the variables and to provide the necessary data for further interpolation. According to the results of WQIG, most of the groundwater wells (98.85%) are polluted due to the existing of the landfill site in the investigated area. Generally speaking, based on the WQIG the water samples were defined as not suitable for drinking applications. Also, the high concentrations of nitrate and hardness in the downstream wells (W1-W11) of the landfill were demonstrated by the results of Kriging assay which can be correlated with the penetration of leachate into these wells. Considering the SAR results, all wells in the studied area are classified as (C3S1) that means the groundwater of this area is suitable for agricultural approaches. Moreover, the reduction in the water quality from the south to the north and northeast was demonstrated by the results of spatial dispersion. Evaluation of the changes in water quality near landfill sites showed that 2149.56 m2 of total area had a relatively poor potential for the region's groundwater recharge.


Subject(s)
Groundwater/analysis , Waste Disposal Facilities , Water Quality , Biological Oxygen Demand Analysis , Cities , Electric Conductivity , Environmental Monitoring/methods , Feces/microbiology , Groundwater/chemistry , Groundwater/microbiology , Hydrogen-Ion Concentration , Iran , Multivariate Analysis , Nitrates/analysis , Refuse Disposal/methods , Solid Waste , Water Pollutants, Chemical/analysis , Water Resources , Water Wells
4.
Environ Geochem Health ; 41(3): 1213-1221, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30390219

ABSTRACT

Chronic exposure to soft drinking water increases the risk of hypertension. We conducted a cross-sectional study in 2017 in two study areas in the Poldasht County to assess the relation of hardness, body mass index and waist circumference with risk of hypertension. Total water hardness was measured by gravimetric methods. Hardness of > 180 ppm was considered to be hard drinking water. The Shiblu and Gharghologh areas had a four times higher mean total hardness level in drinking water (968.69 mg/L as CaCO3) than the Sarisoo and Agh Otlogh (180 mg/L as CaCO3) areas. According to the results of the study, the prehypertension prevalence in areas with high and low water hardness was calculated as 23.15% (18.11-29.15) and 46.84% (37.61-57.64), respectively. Moreover, the result showed the prevalence of hypertension and prehypertension was higher in regions with low hardness than those with high hardness, which was statistically significant (P < 0.001). The results of logistic regression showed that age, body mass index, waist circumference and hardness of drinking water were significantly related to hypertension. Accordingly, hypertension was low in people of regions with high hardness (OR 0.26, 0.17-0.42). This report examined whether total hardness in drinking water was protective against hypertension. This is an important finding for the ministry of human health as well as for the water and sewage company.


Subject(s)
Body Mass Index , Drinking Water/adverse effects , Drinking Water/chemistry , Hypertension/epidemiology , Waist Circumference , Adult , Aged , Cross-Sectional Studies , Female , Humans , Iran/epidemiology , Logistic Models , Male , Middle Aged , Prehypertension/epidemiology , Prevalence , Risk Factors
5.
MethodsX ; 5: 1364-1372, 2018.
Article in English | MEDLINE | ID: mdl-30425934

ABSTRACT

This study was conducted to evaluate the health status of medical equipment's in Neyshabur hospital's intensive care units (ICU) before and after daily cleaning in order to compare the efficiency of the observational and microbial methods in evaluating hygienic conditions and cleaning of the environmental surfaces at the hospitals in Neyshabur. The study was performed in a ten-week period, twice a week before and after daily cleaning according to the ICNA observational method and the ACC microbial method were performed on the selected sites. (before and after daily cleaning in order to compare ICNA observational method and the ACC microbial method which performed on the selected sites). Result showed in total, 826 ICNA checklists were completed in this research for the 13 studied spots, 27.12% of the spots were contaminated before cleaning procedures, which dropped to 7.75% after cleaning. Data of the samples using the ACC index revealed that 74.82 were contaminated and 7.75% were clean. Bottle suction with 8.2% and Electroshock with 1% were the most and the least contaminated spots, respectively. As the results proved, the microorganism of Staphylococcus epidermises is the most grown organism in the intensive care unit. This study suggests that visual assessment is not enough to ensure quality of the process and it is necessary to document the level of cleanliness by quantitative methods. Also preparing the integrated instructions and guidelines of cleaning and disinfection and its continuous monitoring with standard methods would be effective in reducing the microbial contamination.

6.
Data Brief ; 17: 774-780, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29876438

ABSTRACT

The data presented in this article was related to the research article entitled, "The use of Cerastoderma Lamarcki shell for Acid Black 1 adsorption from aqueous solutions." The characterization data of Cerastoderma Lamarcki shell was analyzed using various instrumental techniques (X-ray diffraction and SEM). The kinetic and isotherm data of pH, initial AB1 concentration, contact time, and CLS dosage were investigated. The optimum conditions for AB1 adsorption using CLS adsorbent were found to be 2 g of adsorbent, pH 2, and a contact time of 60 min. The adsorption data of CLS fit well with the Langmuir model and pseudo-second order model. Finally, the experimental data showed that CLS is a suitable and low-cost adsorbent for the removal of AB1 from aqueous solutions.

7.
Environ Sci Pollut Res Int ; 25(23): 23045-23054, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29860684

ABSTRACT

The effect of adding different proportions of natural clinoptilolite zeolite (5 and 10%) to food waste vermicomposting was investigated by assessing the physicochemical characteristics, worms' growth, and maturation time of finished vermicompost in comparison with the vermicompost prepared with no amendment (control). Vermicomposting was performed in 18 plastic containers for 70 days. The experimental results showed that the carbon-to-nitrogen (C/N) ratios were 15.85, 10.75, and 8.94 for 5 and 10% zeolite concentration and control after 70 days, respectively. The addition of zeolite could facilitate organic matter degradation and increase the total nitrogen content by adsorption of ammonium ions. Increasing the proportion of zeolite from 0% (control) to 10% decreased the ammonia escape by 25% in the final vermicompost. The natural zeolite significantly reduced the electrical conductivity (EC). At the end of the process, salinity uptake efficiency was 39.23% for 5% zeolite treatment and 45.23% for 10% zeolite treatment. The pH values at 5 and 10% zeolite-amended treatments were 7.31 and 7.57, respectively, in comparison to 7.10 in the control. The maturation time at the end of vermicomposting decreased with increasing zeolite concentration. The vermicompost containing 5 and 10% zeolite matured in 49 and 42 days, respectively, in comparison to 56 days for the control. With the use of an initial ten immature Eisenia fetida worms, the number of mature worms in the 10% zeolite treatment was 26 more than that in the 5% zeolite treatment (21 worms) and 9 more than that in the control treatment (17 worms). Significantly, natural zeolite showed a beneficial effect on the characteristics of the end-product when used in the vermicomposting of food waste.


Subject(s)
Composting/methods , Garbage , Oligochaeta/physiology , Zeolites/analysis , Animals , Carbon/analysis , Dose-Response Relationship, Drug , Iran , Nitrogen/analysis , Population Dynamics
8.
Iran J Basic Med Sci ; 18(9): 887-93, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26523221

ABSTRACT

OBJECTIVES: Various methods for repairing bone defects are presented. Cell therapy is one of these methods. Bone marrow stromal cells (BMSCs) seem to be suitable for this purpose. On the other hand, lots of biomaterials are used to improve and repair the defect in the body, so in this study we tried to produce a similar structure to the bone by the chitosan and hydroxyapatite. MATERIALS AND METHODS: In this study, the solution of chitosan-nanohydroxyapatite-polyethylene oxide (PEO) Nanofibers was produced by electrospinning method, and then the BMSCs were cultured on this solution. A piece of chitosan-nanohydroxyapatite Nanofibers with BMSCs was placed in a hole with the diameter of 1 mm at the distal epiphysis of the rat femur. Then the biomechanical and radiographic studies were performed. RESULTS: Biomechanical testing results showed that bone strength was significantly higher in the Nanofiber/BMSCs group in comparison with control group. Also the bone strength in nanofiber/BMSCs group was significant, but in nanofiber group was nearly significant. Radiographic studies also showed that the average amount of callus formation (radio opacity) in nanofiber and control group was not significantly different. The callus formation in nanofiber/BMSCs group was increased compared to the control group, and it was not significant in the nanofiber group. CONCLUSION: Since chitosan-nanohydroxyapatite nanofibers with BMSCs increases the rate of bone repair, the obtained cell-nanoscaffold shell can be used in tissue engineering and cell therapy, especially for bone defects.

9.
Iranian J Environ Health Sci Eng ; 9(1): 25, 2012 Dec 13.
Article in English | MEDLINE | ID: mdl-23369642

ABSTRACT

The vermicompost using earthworms (Eisenia Fetida) was produced from food waste and chemical parameters (EC, pH, carbon to nitrogen contents (C/N)) and germination bioassay was examined in order to assess the stability and maturity indicators during the vermicomposting process. The seed used in the germination bioassay was cress. The ranges of EC, pH, C/N and germination index were 7.5-4.9 mS/cm, 5.6-7.53, 30.13-14.32% and 12.8-58.4%, respectively. The germination index (GI) value revealed that vermicompost rendered as moderate phytotoxic to cress seed. Pearson correlation coefficient was used to evaluate the relationship between the parameters. High statistically significant correlation coefficient was calculated between the GI value and EC in the vermicompost at the 99% confidence level. The C/N value showed that the vermicompost was stable. As a result of these observations, stability test alone, was not able to ensure high vermicompost quality. Therefore, it appears that determining vermicompost quality requires a simultaneous use of maturity and stability tests.

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