Showing 48 results for Dust
Ghr Siyahati Ardakani, M Mirsanjari, Hr Azimzadeh, E Solgi,
Volume 11, Issue 3 (12-2018)
Abstract
Background and Objective: The establishment of pelletizing and steel industries in Ardakan suburbs has increased the pollutants such as heavy metals into the environment. The purpose of this study was to investigate the contamination of the area soil by heavy elements around these industries using the pollution index (PI), comprehensive pollution index (NIPI), accumulation index (Igeo) and enrichment index (EF).
Materials and Methods: 57 soil samples were prepared by systematic-random sampling from 0 to 5 cm depth and levels of As, Cd, Cr, Mo, Ni, Pb, V and Zn were analyzed by ICP-OES.
Results: The highest and lowest mean of Igeo (0.49 and 0.36) and PI (2.16 and 1.17), were related to nickel, and the highest EF was calculated for Zn at about 25.1 and the lowest were detected for molybdenum approximately that was 17.1. The EF index of lead, vanadium and zinc, which was 15.8%, 5.3% and 1.8%, respectively, classified the study area in a medium enrichment class. Hot spots of lead, vanadium, nickel and zinc was at the nearest distance to these industries and downstream of wind direction.
Conclusion: Indicators of Igeo and EF showed a low level of soil pollution. The PI and NIPI indices in most stations were classified in medium pollution class, and the highest of these indicators was related to the surface soil of station 30, which was located near the steel industry. Therefore, it can be concluded that the activities of these industries had affected the soil contamination of the study area.
M Moradzadeh, Kh Ashrafi, M Shafiepourmotlagh,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Hydrocarbon processing industries are considered as potential sources of volatile organic compounds (VOCs) due to their specific nature. These compounds can directly or indirectly through producing secondary pollutants have adverse effects on the health of individuals. Therefore, identification of them is an important step in the formulation of control programs. This study aimed to identify the type and amount of the most important volatile organic compounds in the South Pars region.
Materials and Methods: In this study, industrial processes located in the region were investigated and information was gathered for estimation of VOCs emissions. The emission was estimated over a one-year period and was ranked according to three criteria including emission, health hazards and ozone production potential.
Results: The results showed that the greatest emission was due to equipment leakage and storage tanks (64%), cooling towers (21%) and flaring (11%). The 171 VOCs were determined in Plum of these processes and propylene had the greatest contribution (21%). The alkenes had the highest share in total mass (41%) and ozone production (78%). By weighting the list based on the three criteria mentioned above, formaldehyde is the most important emitted VOC and the main sources of it were olefins and aromatic units.
Conclusion: This method can be a useful tool for identifying effective organic compounds in such areas. Here, the optimum control strategy is mitigating of emission of formaldehyde from the aromatic and olefins processes. The next priority is to control propylene, ethylene and butylene emission sources.
M Khalaji, Sa Hiseini, R Ghorbani, N Agh, H Rezayi,
Volume 12, Issue 2 (9-2019)
Abstract
Background and Objective: Nutrient-rich effluents (mainly nitrogen and phosphorus) may lead to algae blooms and many harmful effects in aquatic environments. Micro-algae have been more effective among the various methods used for the removing of nutrients from wastewater. Microalgae Chlorella vulgaris has specific characteristics such as rapid growth, resistant to systems manipulation, simple and inexpensive production technology, as well as the rapid uptake of nutrients such as phosphate and nitrate.
Materials and Methods: In the present study, two concentrations of chlorella vulgaris microalgae (13 and 26 million cells/mL) were injected into dairy effluent, diluted using distilled water by 25, 50 and 75%, and the amount of nutrient removal and microalgae growth were examined during the growth period.
Results: Results indicated that different concentrations of algae at various percentages of dilution (25, 50, 75%) had a significant effect on the removal of nutrients and algal growth (p<0.05). The absorption of nutrients (nitrate, phosphate and ammonia) were 57.01, 51.84 and 43.15 percent respectively that containing lower density of initial algae compared to the treatments of 2nd group (29.15, 51.84 and 43.15 percent) with higher algae concentration. In both algal concentrations, the highest percentage of phosphate and ammonia adsorption were in dilution of 25% effluent and the highest percentage of nitrate adsorption were in the first group with 50% dilution and in the second group with 75% dilution.
Conclusion: The more percentage of nutrients (nitrate, phosphate, ammonia) was eliminated compared to the second group (26 million cells / mL) when the microalgae concentration (group I) was 13 million cells / mL. Absorption of nutrients was decreased by increasing the concentration of microalgae. Regarding to the percentage of nitrate adsorption, the higher absorbance in the dilution was occurred at the highest concentration of algae.
S Shojaee Barjoee, Hr Azimzadeh, A Mosleh Arani,
Volume 12, Issue 4 (2-2020)
Abstract
Background and Objective: Non-biodegradation in nature and creation of adverse health effects in humans is important features of heavy metals. The main objective of this study was to determine the level of contamination, carcinogenic and non-carcinogenic risks of falling dust containing heavy metals on residents around the industrial areas of Ardakan. Another objective was to identify potential sources of heavy metal release into the environment.
Materials and Methods: In this cross-sectional analytical study, the falling dust was collected in summer around Tile and Ceramic, Khak-e-chini, sand and gravel and glass industries by installing 35 Inverted Frisbee traps with artificial grass cover. The concentration of Cd, Ba, Cu, Ni, Cr, Mn and V were measured by ICP-MS. Probable sources of the heavy metal of the dust were evaluated using Pearson correlation coefficient and cluster analysis. Ecological risk indices for determining the level of contamination and proposed relationships proposed by the US Environmental Protection Agency were used to assess the carcinogenic and non-carcinogenic risks.
Results: The highest and lowest mean concentrations of heavy metals were measured for Cd and Ba, respectively. The results of Pearson correlation analysis and cluster analysis revealed three anthropogenic and also natural sources for heavy metals of the falling dust. According to the Ecological Risk Potential Index, Cd in 45.10% of the samples was in a very high class and in 54.88% of the samples was a high class. Pollution class of the ecological risk index of all the heavy metals was medium to high. The carcinogenic risk of Cr and Ba in children and adults was estimated to be higher than 10–4. In both age groups, the Hazard index for each metal was less than 1 and its sum was measured as 1.29 for children and 0.16 for adults.
Conclusion: Cd increases the ecological risk of the falling dust in the area. Ther heavy metal carcinogenic risk results showed that the concentrations of Cr and Ba were higher than standard. Also, the non-carcinogenic risk was higher in children than in adults.
Saeed Sotoudeheian, Behnaz Shirazi Rumenan,
Volume 13, Issue 2 (8-2020)
Abstract
Background and Objective: During the last few years, air pollution and increasing levels of particulate matters (PMs) have become major public health issues in the megacity of Tehran. The high cost of constructing and maintaining air pollution monitoring stations has made it difficult to achieve adequate spatial-temporal coverage of PM data over various regions. In this regard, the use of remote sensing data such as aerosol optical depth (AOD) can be a simple and cost-effective way to overcome the problem.
Materials and Methods: Due to the weakness of univariate linear relationship of PM10-AOD under normal conditions, this relationship has been studied for the time periods of dust storm occurrence during 2007-2010 in Tehran. Satellite product with spatial resolution of 3 and 10 km obtained from MODIS sensor were used to fit the models.
Results: Results showed that the best performance of univariate model was achieved for 5 km radius of AOD extraction and daily mean of PM10 concentrations (r = 0.55). Moreover, the use of meteorological auxiliary variables and the development of multivariate linear regression model have improved the performance of the model (r = 0.64). The final model also exhibited accurate capability for prediction of high PM10 concentrations during dusty days.
Conclusion: Overall, the obtained univariate linear relationships of PM10-AOD was stronger during dusty episodes than those of normal conditions, suggest a higher correlation between AOD and PM10 from dust activities as compared with PM10 originating from other sources. Furthermore, the final developed model could be used to predict daily level of PM10 concentrations during dusty episodes.
Hamid Karyab, Faeze Karyab,
Volume 13, Issue 3 (11-2020)
Abstract
Background and Objective: Since industrial waste management requires accurate knowledge of quantity and quality of solid wastes, this study was conducted to assess quantitative and qualitative characterization of industrial solid waste in Qazvin province, Iran and investigate its related pattern management.
Materials and Methods: Based on the guideline of Iranian Environment Protection Organization, industries were classified into 10 groups. Then according to the abundance of industries in each group, 276 industries and 4 wastewater treatment plants were selected. The Basel Convention criterion was used to identify special solid wastes. Quantitative and qualitative characteristics and management pattern of industrial wastes were determined by referring to the industries and completing a researcher-made questionnaire.
Results: The total types of identified industrial solid wastes were 1726. According to the guideline of Basel Convention, 33.7% of identified wastes were classified as special wastes. The total amount of solid wastes was 38826 ton/month. The maximum solid wastes production was in the chemical industries with 14,380 ton/month. The recovery and recycling rates were 8.96 and 6.44%, respectively, and 36.44 % of industrial waste was sold directly.
Conclusion: The results of the study showed that the management of industrial solid wastes in Qazvin province does not follow a specific pattern. In addition, the quantity and the composition of solid wastes in the study area is a serious potential for environmental pollution and threatening human health. Therefore, it is necessary to establish a center responsible for industrial wastes management and design a centralized industrial waste disposal system.
Abdolmotaleb Seid Mohammadi, Ghorban Asgari, Reza Shokoohi, Parastoo Shahbazi,
Volume 13, Issue 3 (11-2020)
Abstract
Background and Objective: Considering the importance of alkalinity in pH regulation and its buffering role, in this study, the effect of inlet wastewater alkalinity on the efficiency of the anaerobic unit of the wastewater treatment plant. Moreover, a superior chemical compound in providing alkalinity to wastewater was investigated.
Materials and Methods: This study was performed in the treatment plant to determine the relationship between input alkalinity and removal efficiencies of COD, BOD5 and TSS. In order to determine the optimal alkali material for superb anaerobic wastewater performance, four common chemical substances including, NaOH, Na2CO3, Ca(OH)2 and MgO were selected and examined using One Factor At Time (OFAT) test method.
Results: According to the results maximum removal efficiencies were obtained 62, 66.6 and 71.2% for COD, BOD5 and TSS, respectively under alkaline condition of 1260 mg/L CaCO3. Furthemore, the optimal dose to supply one unit of alkalinity by Na2CO3, Ca(OH)2 and MgO were 0.53, 0.54 and 0.3 mg/L, respectively. These values were obtained 5 min contact time and mixing rate of 150 rpm. However, for NaOH the optimal dose supply was obtained 0.35 mg/L for 3 min contact time and mixing rate of 100 rpm.
Conclusion: In conclusion, the performance of anaerobic baffled reactor is highly related to the supply of influent alkalinity to the reactor. In addition, the use of MgO can be considered as a suitable alkaline substance to neutralize acidic wastewater and provide alkalinity for ABR system.
Forough Tajiki, Hossein Mohammad Asgari, Isaac Zamani, Farshid Ghanbari,
Volume 14, Issue 1 (5-2021)
Abstract
Background and Objective: Considering the fact that Iran is located in semi-arid climate and the harmful effects of dust storms on different ecosystems, this study aimed to identify and locate dust storms using fungal bio-aerosols (spores) and HYSPLIT model in southwestern region of Iran.
Materials and Methods: MODIS satellite images and HYSPLIT model were used to investigate the temporal changes of dust masses entering the Khuzestan province. Sampling was carried out from dust storms in Abadan and Khorramshahr cities and from the soil of the dried parts of Hur al-Azim and Shadegan wetlands in a two-month period (from May to July 2019).
Results: The results of numerical modeling show that Abadan and Khorramshahr cities were affected by dust storms of internal origin (from Hur-al-Azim wetland). After isolation of bioaerosols from air and soil samples, a total of 6 fungal genera were identified in soil samples and 6 genera in dust samples of internal origin by PCR-Sequencing method. Talaromyces, Alternaria, Penicillium and Aspergillus were identified as the predominant genera fungi in soil and air samples.
Conclusion: With 70% similarity of fungi found in soil and air samples, it can be concluded that the main source of fungi in Abadan and Khorramshahr is Hur al-Azim wetland.
Fatemeh Bagheri, Mehri Rezayi,
Volume 14, Issue 1 (5-2021)
Abstract
Background and Objective: The aim of this study was to investigate dust origin particulate (PM2.5) in Mashhad city in a long period of time (2014-2019) based on unhealthy days. Furthermore, changes in meteorological parameters and their relationship with dust storms have also been investigated.
Materials and Methods: In order to locate dust pollution hotspots in mashhad air, first, information about unhealthy days of Mashhad city in a 5-year period was obtained from the site of Mashhad Pollutants Monitoring Center and then HYSPLIT model was used to locate air pollution hotspots caused by particulate matter. To verify the results, the outputs obtained from this model were also compared with the DREAM8b model.
Results: By examining the meteorological parameters and its relationship with the outputs obtained from THEHYSPLIT and DREAM8b models, the maximum wind speed and relative humidity were obtained in autumn. There was no rainfall in the studied days (19 days) and the highest temperature was related to summer, indicating the relationship between the occurrences of polluted days due to particulate matter less than μ 2.5, wind speed and relative humidity in autumn. The results of the two models showed that the southern and northeastern regions of Mashhad city had the highest source of dust particles during the studied days.
Conclusion: Although in previous articles, the origin of dust in Mashhad city was announced outside the geographical boundaries of the province, long-term investigation at low altitude (below 10m) showed that local origin of dust have an essential role in air pollution in Mashhad city under unstable atmospheric conditions. Inappropriate use of agricultural lands and severe changes in land use often in the northern region and implementation of construction projects such as the southern belt of Mashhad city play essential roles in increasing PM2.5 particles in the air of Mashhad. This finding shows the importance of decision making for the implementation of soil stabilization projects etc... at the local level.
Moslem Rahimi, Maryam Mohammadi Rouzbahani, Khoshnaz Payandeh, Ahad Nazarpour, Ebrahim Panahpour,
Volume 14, Issue 2 (9-2021)
Abstract
Background and Objective: Due to the spread of dusty air and the transfer of these particles to the cities of Khuzestan province, it is very important to study the status of these particles in terms of heavy metal pollution and their pollution status.
Materials and Methods: In this study, the concentrations of Cr, Cu, Zn, Pb, Ni, Mn, Mg and Fe in the air of 4 cities of Khuzestan province (Ahvaz, Dezful, Mahshahr and Abadan) in dusty and dust-free conditions over a period of 9 months (autumn, winter and spring) were measured in 2018-2019. Due to the spread of dusty air and the transfer of these particles to the cities of Khuzestan province, it is very important to study the status of these particles in terms of heavy metal pollution and their pollution status.
Results: 48 samples in contaminated conditions and 48 samples in non-contaminated conditions were collected at the specific points and exact times using a High Volume sampling pump with a flow rate of 110 L/min for 6 hours. Metal concentrations were measured using ICP. Except for Ni, Mn and Mg, the mean concentration of other studied metals were higher at dusty conditions as compared with their values in non-dusty conditions (p < 0.05). In dusty and non-dusty air conditions the order of heavy metals based on their concentrations were obtained as following: Zn> Mg> Mn> Ni> Cr> Pb> Fe> Cu and Mg> Mn> Ni> Pb> Fe> Cr, respectively. This result shows that the origin of zinc and copper metals and the increase in chromium concentration in polluted air are due to the entering of dust and pollution transfer from the outside area into cities. The cities of Ahvaz, Dezful, Mahshahr and Abadan were highly enriched in terms of heavy metals pollution either in dusty or non-dusty conditions.
Conclusion: The findings of this study showed that despite low concentration of heavy metals in airborne dust particles in clear and dusty air, high health risks of metals such as zinc in cities of Khuzestan province, especially Mahshahr are probable. Further investigation showed that particles are generally derived from intra-city or provincial activities, which call for more attention due to the drought conditions that attributes to more dust formation.
Farah Rashadi, Nahid Navidjouy, Ali Ahmad Aghapour, Mostafa Rahimnejad,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: Microbial fuel cell (MFC) is a new green technology that uses the catabolic ability of microorganisms to produce bioenergy while simultaneously removing organic matter and other wastewater contaminants. Electrode material is one of the factors affecting the performance of microbial fuel cells. The aim of this study was to investigate the performance of microbial fuel cells in COD removal and bioenergy production from synthetic and real beverage wastewater.
Materials and Methods: In this research, a two-chamber microbial fuel cell with Nafion membrane and aerated cathode was set up using two electrodes made of carbon felt and flat graphite after being contacted by synthetic wastewater with a concentration of COD 5000 mg/L and real beverage wastewater. Organic matter removal efficiency and voltage, power density and maximum current were determine.
Results: Experimental results showed that maximum COD removal efficiency of 92 % was achieved in synthetic wastewater and with a carbon felts electrode. In this condition, maximum voltage, power density and output current density of 469 mV, 175.28 mW/m2, and 855 mA/m2, were obtained, respectively. However, by using real industrial wastewater (beverage), maximum removal efficiency of COD, voltage, power density and output current density, related to carbon felt electrodes were obtaines as 84 %, 460 mV, 91/65 mW/m2, and 635 mA/m2, respectively.
Conclusion: The findings showed that synthetic wastewater outperforms microbial fuel cells in terms of bioelectric production and organic matter removal as compared to real wastewater (beverage). The reason for the decrease in the cell performance might be the presence of solids and other confounding pollutants in real wastewater.
Zeinab Alizadeh, Kavoos Dindarloo, Mohsen Heidari,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: Heavy metal (HM) pollution of settled dust on the interior surfaces of elementary schools may affect the health of young students; hence, the health risk of such pollution should be assessed. Therefore, the aims of this study were to measure the content of heavy metals in the settled dust in the indoor of elementary schools in Bandar Abbas and to assess the attributed health risks.
Materials and Methods: In this study, dust samples were collected from the interior surfaces of elementary schools in Bandar Abbas. Settled dust samples were digested using aqua regia solution and then their metals contents were measured using ICP-OES. To assess the health risk attributed to this pollution, daily intake doses through ingestion, inhalation and skin absorption routes were estimated. Then, non-carcinogenic and carcinogenic risks were calculated considering the daily intake doses and toxicity factors.
Results: The average concentrations of arsenic, cadmium, cobalt, chromium, nickel and lead in settled dust were 5.45, 0.58, 11.44, 69.72, 83.95 and 66.72 mg/kg, respectively. The non-carcinogenic risk level for all metals was below threshold, while the carcinogenic risk level for arsenic (2.18×10-6) exceeded the threshold.
Conclusion: This study showed that the settled dust in elementary schools of Bandar Abbas is polluted with various levels of heavy metals. Health risk assessment showed that the exposure to dust containing heavy metals in the elementary schools of Bandar Abbas does not pose significant non-carcinogenic risk, but the carcinogenic risk of As exceeded the threshold limit and should be considered.
Mohammad Hossein Nemati,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: Environmental pollution with heavy metals and consequently their entry into food chains leads to irreparable damage to human health. The aim of this study was to determine the concentration of heavy metals including copper, zinc, lead and cadmium in blood and milk of grazing livestock around Zinc industry in Zanjan province (VSIPZ).
Materials and Methods: A total of 10 samples of grazing blood and milk were taken in each of the four geographical directions of the desired location. Also, in order to compare the current situation in the study area with the non-polluted areas, the control area (Qarah Poshtlu area of Zanjan) was considered. Dry ash method was used to digest organic matter.
Results: The results showed that the concentration of copper in the blood of cows and sheeps and the concentration of lead in the blood of cows in the west of VSIPZ was higher than the control group (p <0.05). There was no significant difference between the study areas and the control in terms of zinc and cadmium concentration in blood samples. Copper concentrations in cows and sheeps milk were lower than the control group in the southern and eastern regions of the VSIPZ, respectively (p <0.05). Zinc and lead concentrations in sheeps’ milk were higher than the control in the south and west of the VSIPZ, respectively (p <0.05).
Conclusion: In general, the results implied that the accumulation of lead in sheeps’ milk in the west of VSIPZ is more than maximum allowable concentration and can endanger the health of consumers.
Zahra Khebri, Fatemeh Sadeghian, Fahimeh Faqhihi,
Volume 14, Issue 3 (12-2021)
Abstract
Background and Objective: Dolochar is the residual ash from the production of sponge iron in the process of direct reduction of iron ore by the coal-based method. In Iran, this waste is transported to the nearest landfill. However, these methods are a major environmental concern due to the fineness of the waste and the presence of heavy metals in its composition. The aim of the present study is to investigate the methods of reusing dolochar in order to solve the environmental problem and further use it as auxiliary materials in applications such as road construction and wastewater treatment.
Materials and Methods: In depth investigation of the word “Dolochar” in Science Direct, SID, and MagIran databases showed that there is no long history of reusing it. Only 14 English articles were found, all of which were used in research; Therefore, the present article deals with the issue of reusing Dolochar in Iran for the first time.
Results: By reviewing previous studies, reuse of Dolochar has been classified into five sections. Dolochar use in wastewater treatment (removal of copper, chromium, paint, phosphate, nitrate, surfactant), removal of chromium from mine effluent (more than 94%), as a synthesis gas, as a filter medium (three times better than sand filters) and it is also used in construction and road construction (alternatives to aggregates).
Conclusion: The high capacity of Dolochar in waste absorption and wastewater treatment shows that it is necessary to reuse it in Iran instead of burying or leaving it in the environment.
Asghar Yavari, Mehdi Moradi Nazar, Seyedeh Maryam Sharafi, Amir Hossein Nafez, Meghdad Pirsaheb,
Volume 15, Issue 1 (4-2022)
Abstract
Background and Objective: It is important to determine the quality of the compost to use compost properly. The aim of this study was to determine the effect of mixing ratio of bulking agent on stability and maturity indices in poultry waste compost.
Materials and Methods: Two piles of sawdust mixture with poultry wastes and volume ratios of 1:1 (W1) and 2:1 (W2) were prepared by Windrow method and a pile containing poultry manure was used as control (W0). In order to determine the stability and maturity indices in compost, the most important physicochemical and biological parameters were studied.
Results: The thermophilic phase lasted about 7 weeks for W1 and about 4 weeks for W2. The initial C/N ratios in the W0, W1 and W2 were 27.10, 31.40 and 56.24, respectively, which eventually reached less than 20. The reduction of organic matter in the three piles was 8.30%, 62.59% and 85.53%, respectively. The thermophilic phase caused a sharp decrease in the population of indicator and pathogenic microorganisms in all piles. The highest dehydrogenase activity in W1 pile was 2.95 mgTPF/gDW.h and by decreasing temperature until the last day, its value decreased to 0.29 mgTPF/gDW.h.
Conclusion: The best ratio for mixing sawdust with poultry manure was 1:1 (v:v). Microbial and enzymatic activities are useful parameters for monitoring poultry composting process and determining the rate of compost stability, and the use of this compost in agriculture will improve soil quality.
Qasim Jalal Smian, Soheil Sobhanardakani, Atefeh Chamani,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: Nowadays, individuals spend a lot of time indoors; thus they are exposed to hazardous compounds including polycyclic aromatic hydrocarbons (PAHs) with teratogen, mutagen, and carcinogen potential. Therefore, this study was conducted to detect, and determine the content and source apportionment of PAHs in office building dust samples of Isfahan metropolis in 2023.
Materials and Methods: In this descriptive cross-sectional study, 84 indoor dust samples were collected from 28 sampling sites. After extraction of analytes, the gas chromatography/mass spectrometry (GC–MS) method was used to determine PAHs content in the samples. Molecular diagnostic ratios (MDRs) were used to determine the origin of PAH compounds. Furthermore, all statistical analyses were performed by SPSS software.
Results: The results showed that 16 priority PAHs were detected in the office building dust samples with the minimum, maximum, and mean values (µg/kg) of 4575, 16589, and 9838. Moreover, based on the results obtained, the mean contents of NAPH, FLU, PHE, FULA, PYR, BaA, CHR, BbF, BkF, BaP, DahA, BghiP, and IcdP species were higher than the maximum permissible concentration (MPC) established by Iran DOE. The results of the MDRs method indicated that although PAHs originated from both pyrogenic and petrogenic sources, the pyrogenic sources had the main role in the pollution of office building dusts with PAHs.
Conclusion: Due to risks arising from exposure to PAHs, detection, determination of contents, source identification, and especially health risk assessment of PAHs in indoor dust of other closed places such as commercial, educational, and recreational buildings as well as households is recommended.
Hossein Masoumbeigi, Davood Motalebi Peykani, Ghader Ghanizadeh, Hamed Akbari Jour, Maryam Esmaeili,
Volume 16, Issue 4 (3-2024)
Abstract
Background and Objective: The health and safety of the employees of any industry is one of the most important issues to prevent the occurrence of accidents. This study aimed to identify and assess related risks in a battery-manufacturing industry using FMEA method and estimate the ratio of the cost of accidents to prevention.
Materials and Methods: In this descriptive and analytical study, the production activities of the industry were first identified. Then the work process, employee duties, and Potential risks were determined by the HAZID method. Evaluation and prioritization of risks were done using FMEA method. Risks whose RPN was higher than 145 were determined as important risks and the ratio of incident cost to accident prevention was calculated.
Results: In 62 active units of this industry, 716 risks were identified and prioritized, 16 of which (2.23%) had RPN above 145 with the highest priority. The financial pulp unit with falling and fire hazards and the assembly unit with the risk of fumes and lead dust leakage with RPN 245 were among the most dangerous units and hazards identified in the industry. In all units except one unit, the ratio of the cost of accidents to prevention varied from 1.2 to 25.
Conclusion: The results showed that it is necessary to consider the correction of the important risks by the industry officials, according to the set priorities so that potential accidents caused by these risks are minimized. This prioritization can play an effective role in optimal risk management and reduce related costs.
Sakine Shekoohiyan, Mojtaba Pourakbar, Asghar Zohdi Shiran, Farshid Ghanbari, Mostafa Mahdavianpour, Ehsan Aghayani,
Volume 16, Issue 4 (3-2024)
Abstract
Background and Objective: The development of the automobile industry has caused various pollutants to enter the environment, one of which is fluoride. Therefore, this study aims to improve the fluoride removal from wastewater pre-paint units of the automotive industry to achieve discharge standards to surface waters.
Materials and Methods: The study is descriptive and on an applied scale, which has been carried out to compare the efficiency of the chemical coagulation process using lime and alum, as well as the electrocoagulation process using aluminum anodes in the presence of lime to remove fluoride.
Results: The results of real wastewater characteristics showed that the pH of wastewater is in the range of 6.1 to 6.3, and its fluoride concentration is in the range of 45 to 55 mg/L. The results of the experiments show that in the most optimal possible state in the chemical coagulation process, it is possible to achieve fluoride removal efficiency in the range of 76 to 81 percent. However, the removal efficiency in the electrocoagulation process using an aluminum anode at a concentration of 5 mol/L of calcium ions, and current density of 20 A/m2 after reaction time of min 20 to 99% can also be achieved.
Conclusion: Considering the high fluoride removal rate (more than 99%) in the electrocoagulation process in the presence of calcium ions, this process can be introduced as an efficient technology for fluoride removal.
Zahra Khodarahmi, Sakine Shekoohiyan, Mohsen Heidari,
Volume 16, Issue 4 (3-2024)
Abstract
Background and Objective: Given the concern about the presence of microplastics in the air and settled dust, and the lack of a standard approach for their detection, it is necessary to investigate the methods and techniques used to study this type of pollution in Iran. Therefore, this study aimed to systematically review the methods and techniques used for sampling, quantification, and characterization of microplastics in the air and settled dust in indoor and outdoor environments in Iran.
Materials and Methods: In this systematic review, the keywords Microplastic*, Air*, Atmosphere*, Dust, Indoor, Outdoor, Iran, and their corresponding Persian equivalents were searched until Dec 1, 2023, in Scopus, PubMed, Web of Science, Google Scholar, Magiran, and SID databases. Obtained articles from the databases were analyzed in order to find the eligible ones.
Results: Overall, 175 articles were found in the initial search, and after removing the duplicates and nonrelevant, 13 eligible articles were included in the study. In most of the studies, the samples were digested with H2O2, and the microplastics were mainly analyzed using a variety of microscopes and µRaman spectroscopy. The abundance of microplastics in the indoor environment was much higher than in the outdoor environment.
Conclusion: The results of this study showed that there is the required equipment for the sampling and analysis of microplastics in air and settled dust in Iran, and these pollutants have been detected in both indoor and outdoor environments.
Hassan Malvandi,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: Dust particles in urban environments are often contaminated with heavy metals, posing significant health risks, particularly to children. Schools are one of the environments where children are exposed to dust particles. Therefore, the aim of this study was to determine the concentration of heavy metals in the dust collected from Mashhad schools and to assess the associated health risks.
Materials and Methods: Dust samples were collected from 27 schools in the fall of 2022 using a brush. The values of various indices were estimated, including the geoaccumulation index (Igeo), contamination factor (CF), pollution load index (PLI), enrichment index (EF), potential ecological risk index (PERI), and health risk indices such as hazard quotient (HQ) and hazard index (HI).
Results: The average concentrations of cobalt (Co), iron (Fe), calcium (Ca), aluminum (Al), lead (Pb), and barium (Ba) were 9.63, 18538.58, 84017.79, 11270.42, 32.07 and 111.56 µg/g, respectively. The Igeo values ranged from -3.69 to 1.51, while the CF values ranged from 0.16 to 4.26. The results of the pollution indices indicated that most of the studied elements were at the first level of pollution, suggesting that the degree of pollution was negligible or low. Additionally, the HQ and HI values were both less than 1.
Conclusion: Overall, the concentrations of the studied elements were not a concern, remaining at uncontaminated levels, and there was no potential health risk associated with exposure to these elements.
