Iranian Journal of Health and Environment
Year:2017 | Volume:10 | Issue:1|Papers Count:12

Background and Objective: Main sources of 4-chlorophenol wastewater are petroleum industry, coal, paper and resin production. The aim of this study was to compare the performance of raw and cationic surfactant modified nano clay in removal of 4-chlorophenol from aqueous solutions.Materials and Methods: The influence of contact time, initial pH of solution, adsorbent dosage and 4-chlorophenol concentration as effective parameters in adsorption process and the influence of modification solution pH and surfactant loading rates were investigated. The modified nano clay was characterized by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) spectroscopy. Finally, the isotherm and adsorption kinetics were investigated.Results: The removal efficiency of 4-chlorophenol was increased by increasing the initial pH from 3 to 11, so that after of 120 min, the absorption efficiency at an initial 4-chlorophenol concentration of 100 mg/L and 0.25 g adsorb ate was 26 and 95.5 % at pH 3 and 11, respectively. Under the same conditions the removal efficiency for the raw nano clay was 2 and 9% at pH 3 and 11, respectively. The FTIR and XRD analyses revealed that the nano clay structural changed from hydrophilic to hydrophobic and the interlayer spacing was increased. The adsorption of 4-chlorophenol on raw and modified nano clay was consistent with Langmuir and pseudo second-order kinetics. The maximum absorption capacity of raw and modified nano clay was 0.5 and 25.77 mg/g, respectively.Conclusion: The modification of nano clay with cationic surfactant increased the adsorption efficiency of 4-chlorophenol.

Background and Objective: The collection of exhaled breath condensate (EBC) is a noninvasive, safe and simple technique to obtain direct samples from lung and use for estimation of the effects of air pollution on human subjects. EBC contains several compounds including simple ions, hydrogen peroxide, proteins, cytokines, deoxyribonucleic acid (DNA), creatine, Electrolytes, trace elements and toxic metals that are diluted by water vapor. The objective of this study was to determine biomarker IL-6 in exhaled breath condensate using an exhaled breath condensate collector.Materials and Methods: The collector was designed and built and was used for collection and condensation of exhaled breath. EBC was taken from 36 young participants. Each person was asked to breathe for 10-15 min and the condensate was kept in a vial. The samples of exhaled breath were cooled down to -20 °C using the collector. The exhaled breath was converted to the solid/liquid mixture and then, the biomarker IL-6 was measured with ELISA (Enzyme -linked immunosorbent assay) method using HS600B R& D Kit.Results: The mean concentration of IL-6 was 1.08 pg/mL in collected samples. The standard deviation of IL-6 concentration was 0.47. Moreover, the average volume of collected EBC was 2.3 mL, ranged between 0.3 and 3.5 mL.Conclusion: The results of this study showed that the volume of the exhaled breath condensate was comparable with similar commercial devices. The average concentration of interlukin-6 was similar to the concentrations reported by other studies. Based on the findings, this equipment can be used by researchers as a suitable device for measurement of IL-6 in exhaled breath condensate.

Background and Objective: Polycyclic aromatic hydrocarbons (PAHs) are a group of organic pollutants that are mostly generated during the incomplete combustion. The main objective of this study was to characterize potential sources of PAHs in Tehran.Materials and Methods: Samples of PM10 were collected at 10 monitoring stations belonging to Tehran Air Quality Control Company (AQCC) and transferred to laboratory for analysis. Besides, a SKC Flite 2 Air Sampling Pump (SKC, USA) equipped with a sampling head and PM10 size-selective inlet was used at four stations to compare the results obtained by collecting AQCC monitors (AQCCMs) tapes with the standard sampling procedures for assessing the interchangeability of two field sampling methods. The principal component analysis (PCA) and diagnostic ratios were applied to identify emission sources and source contribution.Results: The average diagnostic ratios of phenanthrene (Phe) / (Phe+anthracene (Ant)), benzo (a) anthracene (BaA) / (BaA+chrysene (Chry)), fluorantene (Flu) / (Flu+pyrene (Py)), and indeno (1, 2, 3cd) pyrene (IcP) / (IcP+benzo (ghi) perylene (BghiP)) in samples were 0.79, 0.52, 0.43 and 0.38, respectively. These ratios showed that the combustion, especially fossil fuels and motor vehicles, was the main sources of PAHs emission in Tehran. The results of PCA analysis also indicated that 49, 29 and 22% of PAHs sources in Tehran atmosphere were attributed to gasoline-driven vehicles, diesel vehicles and other sources, respectively.Conclusion: According to the results, the combustion, especially fossil fuel and motor vehicle, was the main sources of PAHs emission in Tehran.

Background and Objective: Optimum number of air quality monitoring stations in Mashhad is an essential task for management of the urban environment. However, real monitoring and accurate information on the status of air quality require proper spatial distribution of air quality monitoring stations in the city of Mashhad. The aim of the present study was to determine optimum site locations for air quality monitoring, including Downtown Pedestrain Exposure Station, Downtown Background Exposure Station, and Residential Population Exposure Station by three Multiple-Criteria Decision-Making (MCDM) techniques.Materials and Methods: In the precent study, sites for new air quality monitoring stations t in Mashhad were determined based on a proposed protocol in the United States. Accordingly, the criteria effective for site selection such as population density, distance from existing stations, vicinity to vegitation, vehicle density and other factors were used by applying Analytic Hierarchy Process (AHP), Fuzzy set, and Probability Density Function (PDF).Results: Location similarity of the sites proposed by decision making methods was evaluated to know its reliability. The compactness of distribution of the proposed sites were compared by applying spatial statistic methods auch as Average Nearest Neighbor (ANN) and Standard. The results from ANN indicated that fuzzy set mapped the suggested sites was fully scattered within the entire city of Mashhad and was statistically significant at 99% confidence level. The PDF method also offered the same spatial pattern as fuzzy set. Overall results of this study indicated spatial optimization of suggested sites location for fuzzy set and PDF.Conclusion: The overall results of the decision-making methods used in this study indicated that it is necessary to increase number of air quality monitoring stations at Northwest of Mashhad due to the urban growth in the city. The results also showd the possibility of using Probability Density Function (PDF) as a method of decision-making in GIS for locating and ranking of new air quality monitoring stations.

Background and Objective: Mercury (Hg) is considered as a global pollutant that is widely dispersed in the environment. Monitoring of total mercury (THg) concentration in the sediments without determination of organic mercury (OHg) and selenium (Se) is an unreliable approach to evaluate the precise toxicological effects of Hg. In the present study, concentrations of THg, OHg and Se in the surface sediments of the eastern and western parts of Anzali wetland were investigated. In addition, the correlation of THg and OHg with Se and total organic carbon were analyzed.Materials and Methods: Forty surface sediment samples were collected from the eastern and western parts of the wetland. Analysis of total and organic mercury in the sediment samples were done with Advanced Mercury Analyzer and the concentration of selenium was measured using inductively coupled plasma atomic emission spectroscopy (ICP-OES).Results: The average concentrations of THg in the East and West wetlands were 109.53 and 68.39 ng/g dw, respectively. The average concentration of THg in the sediments of the eastern part of Anzali Wetland was significantly higher than that of the western part (P<0.001). The mean concentrations of OHg in East and West wetland were about 34.91 and 28.84 ng/g dw, respectively. There was no significant relationship. The ratio of OHg to THg showed significant differences in the two studied areas. The average concentrations of Se in East and West wetlands were 156.25 and 163.75 ng/g dw, respectively. There was a significant negative correlation between the concentration of selenium and organic mercury in sediments of the western part of wetland (P<0.05).Conclusion: The THg concentration in the sediments of Anzali wetland was lower in comparison to other studied regions of the world. However, the percentage of OHg in the Eastern and Western part of wetland was high. Therefore, bioavailability and toxicity of Hg would be high in the sediments and aquatic environment. In this study, in spite of high molar ratio of Se to THg, there was relatively high content of OHg. We recommend to measure the various Sespecies that are effectively bound to inorganic Hg and to determine the amount of Se and Hg in aquatic organisms.

Background and Objective: Bottled water consumption is rapidly increasing in recent years for various reasons. The main aim of this study was to survey the geological origin of Iranian bottled water and determine compliance or lack of compliance with the experimental data obtained through sampling 71 brands of drinking bottled water and mineral water.Materials and Methods: In this study the coordinates of access points as a georef of the chosen points were launched on the “Iran geological map” and “Iran mineral and warm water map”. The compliance of laboratory data and water types with the geological data were evaluated and compared with the important ionic ratios of the extracted water through using awh software.Results: In examining 71 brands of the bottled water, 28% of the brands did not agree with the laboratory results, reflected by observing higher levels of bicarbonate in 50% of the bottled waters than those of the geological data. Additionally, 70% of water types were calcic bicarbonate. In the bottled waters from North Alborz range with coastal Time deposits around the Caspian Sea, there was a source of brine or sea water that was about 55% of this amount.Conclusion: Water pass through different geological structures and the dissolution phenomenon might be an important factor for the observed disagreement. Because chemical treatment and use of additives on mineral waters are not allowed it prompts further studies to determine the cause and origin of this issue through sampling from the factory and water source.

Background and Objective: Urban and industrial development has increased concentration of heavy metals in the environment. The goal of this study was to assess the impact of Kerman steel complex on their surrounding soil by heavy metals.Materials and Methods: This study was a snapshot and its type was descriptive analytical research. Heavy metals contents from 60 soil samples (top soil, 0-15 cm) near two Steel Complexes were analyzed using flame atomic absorption spectroscopy (AAS). Source identification and pollution degree indices including enrichment factor (EF) and its percentage (EF%), geo-accumulation index (Igeo), contamination factor (Cf), degree of contamination (Cd) and modified degree of contamination (mCd) were calculated to assess the soil pollution level.Results: The average concentration of Ni, Zn, Fe, Pb, Cr and Cd were 9.98, 54.38, 15063.33, 20.86, 3.54 and 0.038 mg/kg, respectively. The order of average EF for heavy metals was Pb>Zn>Cd>Fe>Ni>Cr. Cf index also showed that 90% of the samples were moderately to significantly polluted with lead element. The results of EF% indicated that Fe (68.18%) had higher enrichment than others. The average values of Cd and mCd indices were 2.90 and 0.48, respectively, that showed low degree of pollution.Conclusion: In this study, Pb and Cd concentration were related with activities of the steel complexes and other metals had a combination of natural and anthropogenic emission sources. The steel complexes should plan to reduce pollutants emission to their environment.

Background and Objective: Identification of potential risks in laboratories and trying to create safe conditions for the staff is very important from different aspects. The main objective of this study was to evaluate the potential risks in the laboratories of three research centers affiliated to Iranian Fisheries Science Research Institute.Materials and Methods: In order to assess and classify risks associated with working in the laboratories (11 laboratories of the Persian Gulf and Oman Sea Ecological Research Center, 9 laboratories of National Shrimp Research Center and 2 laboratories of National Aquatic Organisms Processing Center), the method of “Failure Mode Effects Analysis” (FMEA) as well as statistical methods (concerning compare means) were used.Results: The risk levels in all the laboratories of the Persian Gulf and Oman Sea Ecological Research Center, except for benthos laboratory, could be evaluated as moderate or high. Only in the case of the sample preparation laboratory, significant differences between the values of RPN before and after corrective action was observed. However, in this case the corrective actions have not been effective in decreasing the risk level. In most laboratories of National Shrimp Research Center, the corrective actions were effective in reducing the risk levels (with the exception of three laboratories). In both laboratories of National Aquatic Organisms Processing Center, after the corrective actions, the risk levels were sharply reduced.Conclusion: Considering the high level of risk in many evaluated laboratories, appropriate corrective actions were proposed. But after the second-stage evaluation, it was realized that the proposed corrective measures in some laboratories (especially in the Persian Gulf and Oman Sea Ecological Research Center) were not performed sufficiently and hence the risk still was remained at critical or semi-critical level.

Background and Objective: During the past few decades, air pollution has due to an increase in deaths from been the focus of international attention air pollution. In this study, Volatile Organic Hydrocarbons (VOCs) and Total Hydrocarbons (THCs) in ambient air of a Petrochemical Complex, Iran, was measured. Also, the relationship between these pollutants and some of their urinary metabolites was evaluated in the petrochemical complex workers.Materials and Methods: These pollutants were measured in two stages, in spring (40 samples) and summer (40 samples), in ambient air of the different units of the complex. Urinary metabolites were measured in accordance with the NIOSH standard method using a GC-FID and TD/ GC-MS.Results: Total average of THCs in the spring and summer was 14.06 and 15.85 ppm, respectively; this amount was 14.09 and 16 ppm for VOCs. In summer, the highest values of VOCs (48.19 ppm) and THCs (47.63 ppm) were measured in Recovery unit. Total average of the urinary metabolites including Phenol, Phenylglyoxylic acid (PGA) and Mandelic Acid (MA) was 16.67, 34.8, and 67.24 mg/g creatinine respectively; in spring, it was 15.34, 57.34, 30.5 mg/g creatinine respectively.Conclusion: Background variables such as age, weight, and smoking habit had different impacts on the level of metabolites. The values of measured pollutants were lower than the guideline values proposed by the American Association of Industrial Hygienists (ACGIH). In addition, the values of measured metabolites in urine were less than the biological exposure index (BEI) provided by ACGIH.

Background and Objective: Radon is highly regarded because of its impacts on public health. Northern regions of Iran have a high potential for radon emissions. This research aimed to measure residential radon concentrations in Tarom country- Zanjan and to compare the results with international standards and acceptable values.Materials and Methods: Passive diffusive samplers, Solid State Nuclear Track Detector (SSNTD), with the ability to determine background and longtime concentration, were selected for this study. A total of 30 detectors were located based on a pre-identified network in the residential buildings of Chavarzaq, Ab Bar and Gilvan for a period of three months. Then, detectors were sent to a laboratory for counting the traces.Results: Based on the results, average radon concentrations in Chavarzaq, Ab Bar and Gilvan were 220.51, 95.25 and 119.84 Bq/m3, respectively. The average radon concentration in Tarom was about 130.57 Bq/m3. There was no meaningful relationship between radon concentration with the age of buildings or number of occupants. In comparison of the results with USEPA standards it was observed that among total samples just one of them was in the range of target level, and 15 detectors were in the range of target to action levels and the remaining samples showed high level of radon requiring corrective measures. In addition, 12 detectors showed values less than the reference level of WHO and the remaining detectors had higher values than WHO level.Conclusion: Based on results of this research, soil analysis before construction, application of building materials resistant to leakage and regular monitoring of radon levels in region were suggested.

Background and Objective: Phosphorus (P), as one of the agricultural, industrial and urban wastewater pollutants, plays an important role in eutrophication of surface waters. Use of cationic sorbents for removal of anions including phosphate from aqueous environments is a well-known and effective method. Meanwhile, layered double hydroxides (LDHs) are known as effective anion exchange sorbents. In this study, the efficiency of Mg-Al layered double hydroxide (Mg-Al-LDH) for P removal from aqueous solutions was investigated.Methods and Materials: The Mg-Al layered double hydroxide (Mg-Al-LDH) was synthesized by co-precipitation method and used for removing of P from aqueous solutions. The kinetics and equilibrium studies of phosphate adsorption by Mg-Al-LDH were performed using a batch experiment at different contact times, initial phosphate concentrations, pH values, ionic strengths and doses of sorbent.Results: The results of the kinetics experiments showed that sorption of P with LDH reached equilibrium after 30 min. The highest correlation coefficient was obtained for the pseudo-second order model, indicated that chemical sorption controlled the rate of phosphate sorption by LDH. The results showed that the sorption experiments data were in good agreement with Langmuir model and the maximum adsorption capacity predicted by this model was 37.83 mg P/g LDH.Conclusion: The current study revealed that P adsorption by LDH was increased by increasing contact time and concentration of LDH, but decreased by increasing initial concentration of P, pH and ionic strength. The optimum conditions for phosphate anion adsorption by Mg-Al-LDH were determined as P initial concentration of 20 mg/L, contact time of 120 min, pH of 3.0, sorbent dose of 10 g/L and ionic strength of 0.03 mol/L.

Background and Objective: Nicotine as the most toxic alkaloid in tobacco is one of the compounds which causes human death over the past few decades. The purpose of this paper was to remove nicotine environmental pollution from aqueous solutions using halloysite polythio phene nano composite.Materials and Methods: Halloysite-polythiophene nano composite was prepared using a homogeneous solution of HNT and FeCl3 at 0-5°C by the ball milling technique. In this study, parameters such as pH, contact time and initial concentration of nicotine in laboratory scale were studied and the physical properties of the adsorbent were characterized via fourier transform infrared (FTIR) and scanning electron microscopy (SEM). Then, the absorption results were described using Langmuir and Freundlich isotherms.Results: The results showed that the pH, initial concentration of nicotine and contact time had a direct effect on the nicotine adsorption process. The adsorption of nicotine followed Langmuir isotherm (R2<0.995). Moreover, the best adsorption result was achieved at pH=7, 50mg adsorbent, contact time of 90 min and 50mg/L of nicotine.Conclusion: The results of this study showed that the Halloysite modification as a mineral composite with polythiophene and the synthesis of HNT@PTh nanocomposite can be used as an effective adsorbent to adsorb the nicotine.