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1.
Chronic Obstr Pulm Dis ; 10(4): 412-421, 2023 Oct 26.
Article in English | MEDLINE | ID: mdl-37676651

ABSTRACT

Background: Chronic obstructive pulmonary disease (COPD) is characterized by progressive obstruction of airways due to chronic inflammation. Both genetic and environmental components are risk factors for COPD. The most common cause of COPD is smoking. However, evidence suggests that 17% to 38% of COPD patients are nonsmokers, so other factors like air pollution may also play a role. Objective: The relationship between serum exosomes and exposure to particulate matter (PM) <2.5 and 10 micrometers (µm) in the residing environment of COPD patients and healthy groups was investigated. The correlation between inflammatory cytokine levels with exosome count was also studied. Methods: Peripheral blood samples were taken from 20 COPD patients without a smoking history or a family history of COPD, along with 20 nonsmoker healthy controls. The serum exosomes were counted by flow cytometry using a CD81 marker. The exposure to PM2.5 and PM10 was measured in daily, weekly, and monthly intervals based on the longitudinal measurements of the monitoring stations, and the correlation between exosome count and air pollutants was analyzed. Results: The serum CD81+ exosome count in COPD patients was significantly elevated compared to the healthy controls and this was correlated with daily PM10 (P-value=0.02) and monthly PM2.5 (P-value=0.02) exposure. Although interferon-gamma levels of COPD patients were higher than healthy controls, there was no correlation between exosome count and cytokine level. Conclusions: Considering the significant relationship between air pollutants and the count of serum exosomes demonstrated in the present study, air pollution might be a considerable risk factor in the progression of airway inflammation.

2.
Water Sci Technol ; 73(2): 292-301, 2016.
Article in English | MEDLINE | ID: mdl-26819384

ABSTRACT

The performance of a continuous inflow cyclic biological reactor (CBR) containing moving media was investigated for the degradation of high concentrations of furfural. The effects of hydraulic retention time (HRT) and furfural initial concentrations (loading rate), as main operating parameters, on the bioreactor performance were studied. The results indicated that the CBR could remove over 98% of furfural and 71% of its chemical oxygen demand (COD) at inlet furfural concentrations up to 1,200 mg L(-1) (2.38 g L(-1) d(-1)), a 6-h cycle time and HRT of 12.1 h. The removal efficiency decreased slightly from 98 to 94% when HRT decreased from 12.1 to 10.5 h. The average removal efficiency of furfural and COD during the 345-day operational period under steady-state conditions were 97.7% and 82.1%, respectively. The efficiency also increased approximately 17.2% after addition of synthetic polyurethane cubes as moving media at a filling ratio of 10%.


Subject(s)
Bioreactors , Furaldehyde/metabolism , Water Pollutants, Chemical/metabolism , Biodegradation, Environmental , Biological Oxygen Demand Analysis
3.
J Environ Health Sci Eng ; 12(1): 116, 2014.
Article in English | MEDLINE | ID: mdl-25426295

ABSTRACT

BACKGROUND: Considering the importance of healthcare waste management, following the ratification of the Waste Management law in 2005 and the subsequent approval of its executive bylaw in 2006 and finally the healthcare waste management criteria passing by the parliament in 2008, a review on the status of healthcare waste management is needed to implement the mentioned law properly. FINDINGS: In this retrospective study during six months period all public hospitals in Iran's capital city, Tehran, were selected to conduct the survey. Data collected through an expert-standardized questionnaire was analyzed by using SPSS software. The results of the current status of healthcare waste management in Tehran hospitals showed 5.6% of hospitals were ranked excellent, 50.7% good, 26.4% medium, and the 13.9% of hospitals were ranked weak and 3.5% ranked very poor. CONCLUSIONS: The findings showed that appropriate technologies should be used to have better disposal stage. As the ratified criteria were not fully observed by all the selected hospitals, training courses and comprehensive program conducting by each hospital could be enjoyed as practical tools to implement the all stages of healthcare waste management properly.

4.
J Environ Health Sci Eng ; 12(1): 149, 2014.
Article in English | MEDLINE | ID: mdl-25606344

ABSTRACT

BACKGROUND AND OBJECTIVES: Water shortage problems have led to find either new water resources or improve wastewater treatment technologies in order to reuse. Due to less performance of previous units in microbial removal, disinfection has become a necessary step in wastewater treatment plants. In the present study performance of hydrogen peroxide (HP) and modified Fenton's reagent (HP + Cu(++)) was considered for the disinfection of raw wastewater (RW) and activated sludge effluent (ASE). MATERIALS AND METHODS: Plastic containers of 10-liter volume each were used for RW and ASE sampling. Microbiological analyses of the RW and ASE were performed in triplicate; before and after the disinfection process. Fecal coliforms were analyzed by the direct (without enrichment) multiple fermentation tube procedure. RESULTS: The results showed that using HP alone did not have any significant disinfection capability. In RW and ASE, the highest dose used in this study could reduce fecal coliforms (FC)s by only 1.54 and 1.16 log-inactivation, respectively. However, Maximum removal efficiency of modified Fenton in RW and ASE was 4.63 and 3.41 log-inactivation, respectively. The results suggested that Cu(++) ions used in combination with H2O2 produced very rigorous synergistic effect, and HP disinfection capacity increased significantly. CONCLUSION: Hydrogen peroxide, when applied alone, was not successful in disinfecting of either RW or ASE, and neither the WHO guideline nor the Iranian standard could be met. However, modified Fenton showed very significant disinfection potential and could reduce FCs under World Health Organization (WHO) guideline and Iranian national standard for agricultural irrigation.

5.
Iranian J Environ Health Sci Eng ; 10(1): 5, 2013 Jan 05.
Article in English | MEDLINE | ID: mdl-23369540

ABSTRACT

The majority of anthraquinone dye released to the environment come from antrapogenic sources. Several techniques are available for dyes' removal. In this study removal of reactive blue 29 (RB29) by an advanced oxidation process sequenced with single wall carbon nanotubes was investigated. Advanced oxidation process was optimized over a period of 60 minutes by changing the ratio of acetic acid to hydrogen peroxide, the compounds which form peroxy acid. Reduction of 20.2% -56.4% of reactive blue 29 was observed when the ratio of hydrogen peroxide/acetic acid/dye changed from 344/344/1 to 344/344/0.08 at different times (60, 120 and 180 min). The optimum ratio of acetic acid/hydrogen peroxide/dye was found to be 344/344/0.16 over 60 min. The resultant then was introduced for further removal by single wall carbon nanotubes(SWCNTs) as adsorbent. The adsorption of reactive blue 29 onto SWCNTs was also investigated. Langmuir, Freundlich and BET isotherms were determined and the results revealed that the adsorption of RB29 onto SWCNTs was well explained by BET model and changed to Freundlich isotherm when SWCNTs was used after the application of peroxy acid. Kinetic study showed that the equilibrium time for adsorption of RB 29 on to SWCNT is 4 h. Experiments were carried out to investigate adsorption kinetics, adsorbent capacity and the effect of solution pH on the removal of reactive blue29. The pseudo-second order kinetic equation could best describe the sorption kinetics. The most efficient pH for color removal (amongst pH=3, 5 and 8) was pH= 5. Further studies are needed to identify the peroxy acid degradation intermediates and to investigate their effects on SWCNTs.

6.
Bull Environ Contam Toxicol ; 90(2): 155-9, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23160750

ABSTRACT

Potential of wastewater treatment in car industry and groundwater contamination by volatile organic compounds include perchloroethylene (PCE), trichloroethylene (TCE) and dichloromethane (DCM) near car industry was conducted in this study. Samples were collected in September through December 2011 from automobile industry. Head-space Gas chromatography with FID detector is used for analysis. Mean PCE levels in groundwater ranged from 0 to 63.56 µg L(-1) with maximum level of 89.1 µg L(-1). Mean TCE from 0 to 76.63 µg L(-1) with maximum level of 112 µg L(-1). Due to the data obtained from pre treatment of car staining site and conventional wastewater treatment in car factory, the most of TCE, PCE and DCM removed by pre aeration. Therefor this materials entry from liquid phase to air phase and by precipitation leak out to the groundwater. As a consequence these pollutants have a many negative health effect on the workers by air and groundwater.


Subject(s)
Air Pollutants/analysis , Hazardous Substances/analysis , Motor Vehicles , Organic Chemicals/analysis , Water Pollutants, Chemical/analysis , Chromatography, Gas , Groundwater/chemistry , Industry , Iran , Wastewater/chemistry
7.
Article in English | MEDLINE | ID: mdl-20473804

ABSTRACT

This research was undertaken to evaluate the effectiveness of a hybrid sorbent resin (Lewatit FO36) with goethite structure for removing arsenate from water. Column experiments (with constant flow rate of 8 mL/min, corresponding to 2 min empty bed contact time (EBCT)) were conducted to evaluate the adsorption capacity of resin before and after regeneration and effects of chloride, sulfate, bicarbonate and combined competing ions for arsenate removal from water. The adsorption capacity was approximately 3.229 mg/g that was reduced to 2.826 mg/g after regeneration with 12.48% decrease, which indicates to a successful regeneration procedure. Chloride and sulfate ions had no significant effects on arsenate removal but arsenic removal decreased in the presence of bicarbonate and combined ions. This reduction may be due to the ability of bicarbonate ions in extracting and mobilizing the arsenate ions from iron oxyhydroxides. Results of this study showed that Lewatit FO36 could be developed as a suitable sorbent for arsenate removal.


Subject(s)
Arsenates/chemistry , Ion Exchange Resins/chemistry , Iron/chemistry , Metal Nanoparticles/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Adsorption , Arsenates/isolation & purification , Polymers/chemistry
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