37 research outputs found

    The evaluation and determination of heavy metals pollution in edible vegetables, water and soil in the south of Tehran province by GIS

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    In this study, heavy metals pollutions in waters, soils and vegetables were investigated from farms, near oil refinery in south of Tehran city, Iran (Shahre Ray). The most important heavy metals in Iranian oil are vanadium, cobalt, nickel, arsenic and mercury (V, Co, Ni, As, Hg). In this region, the concentration of heavy metals in soils, well waters and leafy edible vegetables were evaluated in ten different points of farms. Geographic information systems (GIS) were used to estimate the levels of heavy metals concentration at unmeasured locations. After sample preparation, concentrations of heavy metals in vegetables, soils and waters were determined by atomic absorption spectrometry (AAS). Five different leafy edible vegetables from farms, i.e., Persian leek, dill, parsley, spinach and radish were sampled in spring, summer and autumn 2012. In vegetables and well water samples, the concentrations of V, Ni and Co were above the permissible limit of heavy metals as compared to WHO guidelines and the concentrations of these metals in agricultural soils were found to be lower in accordance to soil references. The industrial waste waters had high concentration of heavy metals in this area. In consequence, the results of this study indicate that industrial waste water can cause pollution in well waters and edible vegetables. So, this region is not suitable for cultivation and growing vegetables

    The evaluation and determination of heavy metals pollution in edible vegetables, water and soil in the south of Tehran province by GIS

    No full text
    In this study, heavy metals pollutions in waters, soils and vegetables were investigated from farms, near oil refinery in south of Tehran city, Iran (Shahre Ray). The most important heavy metals in Iranian oil are vanadium, cobalt, nickel, arsenic and mercury (V, Co, Ni, As, Hg). In this region, the concentration of heavy metals in soils, well waters and leafy edible vegetables were evaluated in ten different points of farms. Geographic information systems (GIS) were used to estimate the levels of heavy metals concentration at unmeasured locations. After sample preparation, concentrations of heavy metals in vegetables, soils and waters were determined by atomic absorption spectrometry (AAS). Five different leafy edible vegetables from farms, i.e., Persian leek, dill, parsley, spinach and radish were sampled in spring, summer and autumn 2012. In vegetables and well water samples, the concentrations of V, Ni and Co were above the permissible limit of heavy metals as compared to WHO guidelines and the concentrations of these metals in agricultural soils were found to be lower in accordance to soil references. The industrial waste waters had high concentration of heavy metals in this area. In consequence, the results of this study indicate that industrial waste water can cause pollution in well waters and edible vegetables. So, this region is not suitable for cultivation and growing vegetables

    Using silver nano particles for sampling of toxic mercury vapors from industrial air sample

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    Introduction: Mercury is one of the toxic metals that damages the nervous system and kidneys. Therefore, monitoring of mercury vapors in the environments is essential. .Material and Method: A new adsorbent was made from silver nanoparticles on a bed of quartz. The nano-adsorbent was capable for sampling of the trace amounts of mercury vapor from air. In this study, the required mercury vapor was generate by hydride generation atomic absorption spectrometry and the necessary analysis was performed by cold vapor atomic absorption spectrometry. . Results: Mercury vapors in the Stationary phase, were concentrated as much as 2300 times (Atomic absorption detection limit was 1.15 microgram per liter of air). Thus by this stationary phase, the trace amounts of mercury vapors can be detected up to 0.5 nano gram per liter of air. The detected value of the presented method is 200 times lower than the occupational safety and health administration (OSHA) standards for mercury vapors. Heater accessory at the temperature of 245 °C was used for thermal desorption of mercury from nano silver adsorbent. Optimal time of desorption was obtained 150 seconds and the Repeatability of the method was 58 times. The mercury vapors absorbed on nano silver adsorbent could be maintained at 80 days at the room temperature (25 °C). .Conclusion: The presented adsorbent is very useful for sampling of the trace amounts of mercury vapors from air. Moreover, it can be regenerated easily is suitable or sampling at 25 to 70 °C. Due to oxidation of silver and reduction in uptake of nanoparticles, oven temperature of 245 °C is used for the recovery of metallic silver. Low amount of adsorbent, high absorbency, high repeatability for sampling, low cost and high accuracy are of the advantages of the presented method

    Neuropsychological effects of long-term occupational exposure to mercury among chloralkali workers

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    BACKGROUND: Mercury is one of the most well-known toxic metals for humans. Chloralkali workers are exposed to mercury vapours extensively, which may be associated with neurotoxicity. OBJECTIVE: The aim of this study was to determine the associations between mercury concentration in blood and air samples, and mercury's neuropsychological effects among chloralkali workers. METHODS: This study was conducted on 50 chloralkali workers as the exposed group and 50 non-industrial office workers as the unexposed group. All subjects were assessed using the Hamilton Depression Rating Scale, Piper Chronic Fatigue Scale and Essential Tremor Rating Scale. Mercury concentration was measured in blood and air samples using cold vapour atomic absorption spectrometry. RESULTS: There was significantly more severe fatigue, depression and tremor in the exposed group compared with the unexposed group. The mean concentration of blood mercury in the exposed group was 22.59±12.5μgL-1 which was significantly higher than the unexposed group (1.28±1.05μg L-1). Based on multiple linear regression, shift work, smoking, fatigue, depression and tremor were predictor variables for blood mercury concentration. CONCLUSIONS: This study indicated that this sample of chloralkali workers suffered from neuropsychological problems such as fatigue, depression and tremor, which is probably related to mercury exposure. © 2020-IOS Press and the authors. All rights reserved

    A novel method based on functionalized bimodal mesoporous silica nanoparticles for efficient removal of lead aerosols pollution from air by solid-liquid gas-phase extraction 03 Chemical Sciences 0306 Physical Chemistry (incl. Structural)

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    In this study, the enrichment and novel sorbent based on functionalized bimodal mesoporous silica nanoparticles (HS-UVM7 and NH2-UVM7) was used for removal of lead aerosols pollution from air by solid liquid gas phase extraction method (SLGPE). In bench scale set up, the lead aerosols (Pb (NO3)2, PbO was generated by dispersive aerosols generator system (DAGS) and removed from air by reaction loop (RL) / impinger trap (IT) in a liquid phase which was mixed with nano adsorbent in optimized pH. The effect of parameters such as, flow rate, volume of liquid phase, time stirring, temperature, concentration, pH and amount of sorbent (mg) were studied and evaluated by flame atomic absorption spectrometry (FAAS). In optimized conditions, the adsorption capacity of HS-UVM7 and NH2-UVM7 for Pb(NO3)2 aerosols was obtained 255.6 mg g-1 and 177.6 mg g-1, respectively which was more than UVM7. The lead oxides aerosols (PbO) were extracted only by HS-UVM7 at acidic pH with the adsorption capacity of 271.2 mg g-1. The characterization of SEM, XRD, TEM, and FTIR showed that the HS-UVM7 has beneficial surfaces for removal of (Pb (NO3)2 and PbO aerosols from the air by SLGPE method at pH = 5. The method validation was confirmed by standard addition and NIOSH method. Figure not available: see fulltext. © 2020 Springer Nature Switzerland AG

    A survey of neurobehavioral symptoms of welders exposed to manganese

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    Introduction: Occupational exposure to manganese can cause neurobehavioral symptoms. The aim of present study was to survey neurobehavioral symptoms of welders exposed to manganese- containing welding fumes and compare the frequency of these symptoms with unexposed group. .Material and Method: Twenty seven of welders as exposed group, and 30 administrative workers as unexposed controls, were participated in this study. Neurobehavioral symptoms data were gathered using Q16 questionnaire. Manganese concentrations were determined according to the NIOSH 7300 method. After preparing of blood samples using microwave assisted acid digestion method, all samples were analyzed to determine manganese by graphite furnace- atomic absorption spectroscopy (GF-AAS). .Result: The mean exposure to air manganese was 0.023± 0.012 mg/m3. Manganese concentrations in blood samples of welders (15.88± 7.11 µg/l) were significantly higher than unexposed workers (9.37± 8.70 µg/l), (P-V<0.05). The frequency of neurobehavioral symptoms of welders was significantly higher compared to unexposed workers (P-V<0.05). The correlation between neurobehavioral symptoms and blood manganese was significant for welders (P-V<0.05). . Conclusion: Welders’ exposure to manganese and its potential health effects should be evaluated periodically and effective control measures should be applied in order to to prevent neurobehavioral symptoms

    Evaluating X-ray absorption of nano-bismuth oxide ointment for decreasing risks associated with X-ray exposure among operating room personnel and radiology experts

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    Introduction: During recent years, carcinogenic effects of X-ray have been proven. Todays, lead is used in many equipment such as  coats, thyroid shield, and gloves for body protection against X-ray. However, these equipments have several disadvantegous including toxicity, heaviness, and inflexibility. Hence, newer methods like protective semisolid products (cream, ointment) for topical application are being replaced. Therefore, the feasibility of using an ointment containing bismuth oxide nanoparticles (Bi2O3) as a X-ray adsorbent was evaluated in this study.   Methods and Materials: First, synthesis of Bi2O3 and then formulating it in the form of ointment was investigated. In this study, X-ray device and dosimeter was employed to check the X-ray absorption in different thickness of bismuth oxide nanoparticles ointment.   Results: In dosimetry test, the protective effect of the ointment containing Bi2O3 nanoparticles was evaluated significantly (P<0.05) better than control group and equal sheet lead group. Dosimetry tests showed that the bismuth oxide nanoparticles ointment and cream absorb  56% of the radiation whereas this value is  41% for lead. K absorption edge for bismuth is higher than other metals and its nanoparticles have more absorbent surface to volume ratio (S/V).   Conclusion: It seems that due to higher atomic number and lower toxicity, Bi2O3 nanoparticles have better efficiency in X-ray absorbtion, comparing to the lead. Cream and ointment of bismuth oxide nanoparticles can be used as X-ray absorbant for different professions such as physicians, dentists, radiology experts, and operating room staff and consequently increase health and safety of these employees

    Nanographene oxide modified phenyl methanethiol nanomagnetic composite for rapid separation of aluminum in wastewaters, foods, and vegetable samples by microwave dispersive magnetic micro solid-phase extraction

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    A new method based on graphene oxide modified (4-phenyl) methanethiol nanomagnetic composite (Fe3O4@4-PhMT-GO) was used for extraction and separation of aluminum from wastewater, food, and vegetable samples in aluminum cookware by microwave dispersive magnetic micro solid-phase extraction (MDM-μ-SPE). In optimized conditions, the working range (WR), the linear range (LR), the limit of detection (LOD), and enrichment factor (EF) were obtained 5�5200 μg L�1, 5�1600 μg L�1, 1.5 µg L�1, and 48.8, respectively (RSD = 2.5). By MDM-μ-SPE procedure, the aluminum concentrations in baking rice and spinach with aluminum cookware were obtained 97.43 ± 2.57 mg g�1 and 131.64 ± 5.18 mg g�1, respectively which was analyzed by atom trap flame atomic absorption spectrometer (AT-FAAS). The results showed, the aluminum concentrations in cooked foods with Teflon cookware were less than aluminum cookware. The methodology was validated by standard reference materials (SRM) and inductively coupled plasma mass spectrometry analysis (ICP-MS). © 2021 Elsevier Lt
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