26 research outputs found

    Determination of benzene, toluene ,ethyl benzene and xylene (BTEX) in ambient air painting workshops car compared to the air surrounding residential areas during winter 1394 in Yazd city .

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    Abstract Title: Determination of benzene, toluene ,ethyl benzene and xylene (BTEX) in ambient air painting workshops car compared to the air surrounding residential areas during winter 1394 in Yazd city . MH.Salmani1 , MH. Ehrampoush2, MH.Mosadegh3 , SMH. Sharifi4* 1Depatment of Health , School of Health , Shahid Sadoughi University of Medical Sciences,YAZD, IRAN 2Depatment of Health , School of Health , Shahid Sadoughi University of Medical Sciences,YAZD, IRAN 3Depatment of Pharmacology , School of Pharmacy , Shahid Sadoughi University of Medical Sciences,YAZD, IRAN 4Student of M.Sc Environmental Health Enginiering , international branch , Shahid Sadoughi University of Medical Sciences,YAZD, IRAN ( Responder) Introduction: benzene, toluene , ethyl benzene and xylene (BTEX) such as volatile organic compounds and air pollutants are important that have similar chemical and physical properties. The compounds in solvents, petrochemicals and colors plentiful and are released and even in small amounts as well as the risks to industry employees and the surrounding residential areas along their industry (50 meters radius around). The purpose of this study was to determine the amount of these pollutants in ambient air car paint workshops, as well as residential areas around the city of Yazd. Materials and Methods: In this study, environmental air from air painting workshops Yazd city cars in winter 1394 and residential areas surrounding air workshop by Tedlar bags and personal sampling pump were collected and using gas chromatography (GC / FID) analysis and evaluation of data were then with statistical software SPSS-16 were analyzed. Results: The results showed that the average concentration and standard deviation of pollutants benzene, toluene , ethyl benzene and xylene in the ambient air painting workshops are (2/14 ± 0/73) , (4/09 ± 1/97), (1/08 ± 0/290) and (3/05 ± 1/00) ppm  and the average concentration and standard deviation of pollutants benzene, toluene , ethyl benzene and xylene in the surrounding air workshops (50 meters radius around) in Yazd city car are (0/960 ± 0/202 )  , (1/50 ± 0/409) , (0/613 ± 0/420) and (1/38 ± 0/452) ppm. Conclusion: The concentration of benzene in the air of car painting workshops is several times higher than the standard limit expressed by the Office of Environmental Health Risk Assessment health Vocational and Technical Committee (0/5 ppm) and the average concentration of pollutants in the air of 50 meters radius around the workshop is more than the permitted standard while concentrations of toluene , ethyl benzene and xylene are less than the limit

    Usage of Failure Mode & EffectAnalysis Method (FMEA) forsafety assessment in a drug manufacture

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    Background and Aims: This study was hold in purpose of recognizing and controlling workplacehazards in production units of a drag ManufactureMethod:So for recognition and assessment of hazards, FMEA Method was used. FMEASystematically investigates the effects of equipment and system failures leading often toequipment design improvements. At first the level of the study defined as system. Then accordingto observations, accident statistic, and interview with managers, supervisory, and workers highrisk system were determiner. So the boundaries of the system established and informationregarding the relevant Components, their function and interactions gathered. To preventConfusion between Similar pieces of equipment, a unique system identifier developed. After thatall failure modes and their causes for each equipment or system listed, the immediate effects ofeach failure mode and interactive effect on other equipment or system was described too. Riskpriority number was determined according to global and local criteriaResults: After all some actions and solution proposed to reduce the likelihood and severity offailures and raise their delectability.Conclusion :This study illustrated that although of the first step drug manufacture may seem safe,but there are still many hazardous condition that could cause serious accidents, The result proposedit is necessary: (1) to develop comprehensive manual for periodical and regular inspection ofinstruments of workplaces in purpose of recognize unknown failures and their causes, (2) developa comprehensive program for systems maintenance and repair, and (3) conduct worker training

    Selenium and Human Health

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    Introduction: Selenium is an essential element for human health and it is toxic at high concentrations. Selenium is a constituent component of selenoproteins that have enzymatic and structural roles in human biochemistry. Selenium is a best antioxidant and catalyst for production of thyroid hormone. This element has the key role in the immune function; prevention of AIDS progression and the deactivity of toxins. Furthermore, selenium is essential for sperm motility and can reduce abortions. Selenium deficiency was also associated with adverse mood states. The findings regarding cardiovascular disease risk related to selenium deficiency is unclear, though other conditions such as vascular inflammation, oxidative stress and selenium deficiency can cause this disease too. Moreover, consuming of 60 mg of selenium per day may be associated with reduction of cancer risk. In this study, a review of studies has been performed on the biochemical function of selenium toxicity, and its effects on human health. Furthermore, certain identified cancers associated with selenium have been discussed to absorb more attention to the status of this element and also as a guide for further studies. Selenium plays the dual character (useful and harmful) in human health, and then it is necessary to determine the concentration of this element in body fluids and tissues. An appropriate method for routine measurement of selenium in clinical laboratories is electro thermal atomic absorption spectrometry (ETAAS) with very low detection limit and good precision

    Application of the Photocatalytic Process of Ag-ZnO / UV-C for the Degradation of 2,4-Dichlorophenoxyacetic acid In Aqueous Aolutions

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    Introduction: A variety of pesticides is used to combat weeds. Check-resistant residues of contaminants in drinking water resources have detrimental effects on human health and on environment. In recent years, advanced oxidation methods o remove toxins from the environment, particularly the aquatic environment is further considered. Methods: In this study, samples adding different concentrations (mg/L10, 20, 30) of pesticides were prepared in deionized water. Specimens of the individual phases in a batch reactor with the catalyst (g / L 1 ,2, 3 and, 4), pH (3,5, 7, 9, 11) and contact time (60, 120, 180, 240 min) exposure contacts coupled Ag / ZnO and UV-c was performed. Results: The results showed a reduction in pesticide concentrations (2, 4-D) and increasing the reaction time, the degradation efficiency increases. The highest degradation efficiency was for 240 minutes and the initial concentration of toxin was (2, 4-D) 10 mg/L  to 96 percent. The kinetics of the elimination of toxins (2, 4-D) by the process of photocatalytic Ag / ZnO in the presence of UV-C light corresponded to the pseudo first. CONCLUSION: The most effective degradation of toxins (2, 4-D) by the process of photocatalytic Ag / ZnO under conditions of neutral pH and with increasing reaction time and reduce toxin concentrations (2, 4-D) is the result

    Evaluation of synthesized iron oxide nanoparticles in removal of copper ions from aqueous solution

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    Abstract Introduction: water source pollutant, result of direct releasing of metal ions to environment, is one of the most important problems in the world. In this study, efficiency of synthesized iron oxide nanoparticles in presence of extract tangerine Peel was investigated for removal of copper ions in the solution. Methods: Iron oxide nanoparticles were prepared by co-perception method using Tangerine Peel extract. The Tangerine Peel extract used to decrease of nanoparticle size and to prevent of particles coagulation. The effect of different parameter includes initial copper concentration, adsorbent dose, contact time and solution pH was investigated on removal of copper. The experimental data were fitted to Langmuir and Freundlich isotherm models. Results: The results showed that the removal efficiency was increased by increasing of pH and decreased from 88% to 81% by increasing of initial copper concentration from 5 mg/l to 10 mg/l. The most removal percent was 92% when copper concentration was 5 mg/l and adsorbent doze was 0.6 g in 100 ml suspension. Conclusion: The results showed the removal efficiency is depended on to pH. The increase of copper concentration decreased the removal efficiency. Adsorption experimental data were in good accordance with Langmuir isotherm model. The synthesized iron oxide nanoparticles with extract Tangerine Peel is a good adsorbent for removing of heavy metals from aqueous solution

    Evaluation of Adsorption Process in Dye Removal from Industrial Wastewater

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    Abstract Introduction: Innovative processes for treatment of industrial effluents containing dyes and heavy metals are often used to reduce the toxicity of these compounds in order to reach the refining standards. Recently, a special focus on innovative processes took place for physical and chemical removal by new absorbent, biomass absorption, membrane filtration, radiation, and electrochemical coagulation. In this study, the recent developments and application of different treatment methods was analyzed for dyes removal from industrial wastewater. Methods: This study extracted from 45 articles of different sites between 1997 until 2014, which it was evaluated the advantages and limits of adsorption process. The main operating conditions affecting on the absorption process such as pH, temperature, concentration of pollutants and dose of contaminants were evaluated for dyes treatment. Conclusion: This review study indicated that the pH factor was frequently studied and its impact has been widely studied in treatment of contaminated wastewater with dyes. Previous studies had shown that adsorption process will be the most promising methods of treatment in the complex systems at the near future. Adsorption process for removing of organic contaminants and metals recovery systems have shown a good performance in the batch reactor. Among of conventional processes, adsorption is known as one of the most effective technology for wastewater treatment of organic and inorganic pollutants with concentrations less than 1000 mg/l. It is important to note that the cost of treatment method varies depending on the used process and the local conditions. In general, the key factors in choosing a method are usability of method, simplicity of design and cost benefits. The adsorption process provided all benefits and it is suitable for the removal of dyes from wastewater

    Evaluations of Effective Factors on Efficiency Zinc Oxides Nanoparticles in Cadmium Removal from Aqueous Solution

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    Introduction: Cadmium is a heavy metal with high toxicity and is best known as a carcinogen element. For protecting human health and environment it is necessary to remove excess Cadmium from industrial wastewater before discharging it to surface and ground water. In this study the efficiency of Zinc Oxides Nanoparticles in Cadmium removal from aqueous solution was evaluated. Methods: This is a laboratory experimental study. Adsorption tests were performed in a batch reactor in a laboratory scale using zinc oxide nanoparticles and the effect of initial cadmium concentrations, adsorbent dose, pH, and contact time on the removal efficiency was studied. Theresidual cadmium concentration in the solutionwas determined using flame atomic absorption spectroscopy Varian AA20 made in Australia. Finally for designing graphs, we used Excel software. Results: The results indicated that the adsorption process is affected by different parameters such as initial pollutant concentrations, adsorbent dose, pH, and contact time and Cadmiumremoval efficiency increases with increasing adsorbent dose and reaction time and decreases with increasing initial concentration of Cadmium. Therefore, it is observed that by raising the initial Cadmium concentration, the adsorption rate increases. The maximum efficiency of adsorptionin pH=7amounted to 89.6%. Conclusion: It is concluded that Zinc Oxide nanoparticles have proper efficiency in removal of Cadmium from aqueous solutions and can be used in the treatment of wastewater that contains ion Cadmium. However, its efficiency is deeply dependent on ion strength and the interaction of other metals in wastewater

    Differential Expression Pattern of the Human Endoderm-Specific Transcription Factor Sox17 in Various Tissues and Cells

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    Background: Sox17 is a member of the Sry-related high mobility group (HMG) of transcription factors that is necessary for endodermal formation and liver development in multiple species. Sox17 gene expression is required for formation of definitive endoderm that gives rise to various tissues.Objective: To examine the expression of Sox17 in various human tissues and cells.Methods: Semiquantitative polymerase chain reaction (RT-PCR) was used to evaluate the expression of Sox17 in adult liver, small intestine, spleen, placenta, fetal liver as well as embryonic stem cells (ESCs), and human HepG2 hepatoma cell line.Results: Low Sox17 gene expression was observed in ESCs. However, there was no expression of Sox17 in human placental tissue, small intestine, adult liver, spleen, and HepG2 cells. But its expression in human fetal liver was very high.Conclusion: The data presented in this study reflect the differential expression pattern of Sox17 in the fetal development during early mammalian endodermal formation which is temporal and tightly regulated

    The Evaluation of Removal Efficiency of COD Due to Water Contaminated by Gasoline by Granular Active Carbon

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    Abstract Introduction: Oil pollution has severe effects on the water resources, environment, soil and human health. One of the most important goals of environmental engineers is removing of contaminants from water. Adsorption process is an effective manner for removing of contaminants in aqueous solutions. In this study, the efficiency of adsorption process by activated carbon granular has been investigated to decrease chemical oxygen demand (COD) due to gasoline in water. Methods: This study was an experimental study that was conducted in laboratory scale. The adsorption process was done batch in 100 ml in closed Erlenmeyer and the effective parameters such as the initial concentration of contaminant (1, 2% V/V) and contact time (2, 5, 10, 20, 30 and 60 min) were adapted. In all experiments, pH of 7.85 and the adsorbent mass of 1g/100mL were fixed. The COD values were measured by return reflux method according to D 5220 method presented in Standard Methods book for water and wastewater examinations. Data were analyzed with Freundlich, Langmuir and Temkin isotherm models for determining of adsorption isotherm. The charts were drawn by Excel software. Results: The results of this study showed that the average of gasoline removal percent in 1 and 2% was 93.64±3.17 and 53.7 ± 22.76, respectively that the difference was significant (P-value0.05). Regression coefficients showed that adsorption data followed by Freundlich isotherm model and pseudo-second order kinetic. Conclusion: We can conclude from this study that the activated carbon is an appropriate adsorbent for decreasing of COD due to gasoline contamination in water. The use of this adsorbent can well decrease COD of water contamination due to gasoline at times of 30 min
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