Vol 2 No 4 (2017): Autumn 2017

Original Research

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    Introduction: Tile industry workers are at great risk of multitude chemical agents that can have short-term or long-term adverse effects on the physical and/or mental health. This paper studied Incidence of physical complications in tile industry workers with occupational dust exposure.
    Materials and methods: Workplace air sampling was done through 0 - 500 method of National Institute for Occupational Safety and Health (NIOSH) in different parts of a tile factory. Physical complications incidence was calculated in two groups (49 people in exposed group and 49 people in non - exposed group) by a researcher-designed questionnaire.
    Results: The average concentration of dust was 232.8 ± 23.3 mg / m3 in the crusher, 76.4 ± 47.2 mg / m3 in the ball mill spray, 37.5 ± 34.9 mg / m3 in the press, 27.6 ± 7.2 mg / m3 in the glaze, and 7.6 1.2 ± mg/m3 in the administrative sectors. In the exposed group, various physical complications were observed such as coughing up sputum 28.6 %, wheezing 28.6 %, dyspnea 30.6 %, hoarseness 38.8 %, dryness of throat 55.1 %, blurred vision 20.4 %, eye irritation 49 % which were observed statistically significant difference with those of the non - exposed group.
    Conclusions: Since the dust concentration mean in the exposed group was above the Threshold Limit Value (TLV), the physical complications in these workers can be associated with the high concentration of dust from the raw material in their workplace.

  • XML | PDF | downloads: 97 | views: 222 | pages: 175 - 180

    Introduction: Motor vehicles are the most important sources of gaseous and particulate matter emission in urban areas with the serious health effects which cause the respiratory and cardiovascular diseases and mortality. Motor vehicles emit a broad range of PM from 0.003 to 10 μm.
    Materials and methods: The exhaust emission of BRT and diesel buses was samples by portable environmental dust monitor, model EDM 107 during summer and winter 2016. ANOVA was applied at a significant level (Pvalue < 0.5) to compare the amount of emitted particles in each season.
    Results: The lowest concentration of emission was seen in BRT buses and the average number of particles in every liter of exhaust sample was 776330 ± 40428. The amount of emission from BRT buses in winter was 166217 ± 971870. There is a significant difference between total emissions of nanoparticles releasing by diesel and BRT buses in each season, but there isn’t any significant difference between the emissions of nanoparticles releasing by diesel buses in summer and winter.
    Conclusions: There was the high emission of particles emitted by diesel buses in both seasons. Since the impacts of particulate matters on health should be considered in Tehran, planning the best locations for bus terminals and also monitoring these places continuously are recommended.

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    Introduction: Drying of parts of Lake Urmia has exposed to salt domes in various areas of the lake. As such, the economic incentive for salt harvesting has been improved due to the easier access. Nonetheless, these operations have the potential of generating particulate air pollutants that can adversely impact immediate and distant agricultural and residential areas. Dispersion modeling is needed to evaluate the effect of various operational parameters on the generation and transport of these particulates.
    Materials and methods: A mine with the capacity of 1250 tons /day in the area of Qobadlu and two other salt sites around lake Urmia were considered for modeling. Major activities that contribute to pollutant production include transport vehicles and wind erosion from storage salt piles. Wind erosion from the piles was evaluated under different scenarios using CFD approach. Using emission factors for other activities, topographic and climate data, Gaussian dispersion of particles was conducted using ADMS modelling system.
    Results: The results showed that transportation of particles occurs towards the lake with negligible concentrations for distances within the 150 m radius; observed trend was a reduction from concentrations of around 100 μg / m3 at the site to 5 μg / m3 at the afore - mentioned distance. Layout optimization of storage piles and erection of barriers respectively resulted in up to 17 % and 44 % reduction in particulate generation from pile surfaces.
    Conclusions: The results of this research have been used in the preparation of the environmental guidelines for salt harvesting in compliance with the lake Urmia restoration directives.

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    Introduction: Indoor air pollution plays important role on human health. People spend 90 % of their time in closed spaces, which cause the interest of study about indoor air quality. The main objective of the present study was to design a hydroponic system for indoor air remediation by bacteria and mondo grass (Ophiopogon japonicus).
    Materials and methods: Soil surrounding mondo grass roots was sampled and enriched in a mineral salt medium, and at the end enriched consortium was used for bioreactor inoculation. The following is a brief overview of the biofiltration system: Indoor air, sucked by an air compressor, was injected to the bioreactors and circulated to the pots. In order to study the efficiency of biofiltration system, phenol was added to the nutrient solution on a daily basis. After determining the optimum temperature, the system’s ability to degrade various concentrations of phenol was measured.
    Results: Results showed that enriched consortium had high degradation ability. Among the isolated strains, Staphylococcus epidermis and Pseudomonas sp. were found to be more efficient. Biodegradation rate was higher in 35°C and in all selected phenol concentrations (500 to 1500 mg/L) biofiltration system was able to degrade phenol but in high concentrations, system performance was somewhat reduced.
    Conclusions: In a nutshell, the results revealed significant ability of hydroponic system for remediation of air by bacteria and plant. Obviously, the system may be seen as an important tool in air bioremediation.

  • XML | PDF | downloads: 104 | views: 219 | pages: 199 - 204

    Introduction: PM2.5 is one of the most important air pollutants, affecting human health by penetrating in to the alveolar area. Thus prediction of PM2.5 concentration and its behavior and also its seasonal and spatial variation are necessary for public health protection.

    Materials and methods: For this purpose, PM2.5/ PM10 was calculated in different seasons and different stations in Tehran city during 2016. Also the PM2.5/PM10 ratio was compared in different area of the city. Then achieved results were analyzed by R.

    Results: Seasonal variation of this ratio was significant. It shows that the maximum and minimum value of PM2.5/ PM10 was in winter and summer, respectively. It seems it is due to the incomplete combustion of fuel in winter. Also we found that the PM2.5/ PM10 ratio in the western area of city is significantly higher than the east. It can be due to the pollutants transmission from the town located in close proximity to the west of Tehran.

    Conclusions: PM2.5 / PM10 ratio can be different in various situations. It can be affected by the several factors such as pollutant sources, meteorological and seasonal factors and also traffic pattern. The PM2.5/PM10 ratio can alert corresponding agencies for prediction the air quality that happens every year periodically.

Review Article(s)

  • XML | PDF | downloads: 167 | views: 292 | pages: 205 - 210

    Air pollution is one of the prevalent causes of respiratory disorders. The main air pollutants are NOx, SOx and O3 that affect quality of life and health. Therefore, assessment of air pollutants effects on the pathogenesis of asthma and allergic diseases may lead to reach a better quality and reduce the prevalence of the diseases. The sample size of this study was according to the index articles containing the terms” Air pollution, Asthma and Allergy”. For writing of this review, 55 articles were studied. Air pollutants induced nonspecific immune and allergic inflammation with enhancing the production of IL - 4, IL - 5, and IL - 13 by Th2 lymphocytes. Our present research demonstrates that, there is significant relationship between air pollution and asthma and allergic diseases. Therefore, air pollution plays role in the pathogenesis and exacerbation of the allergic diseases.