Showing 233 results for Co
Mohammadali Zazouli, Samaneh Dehghan, Mahdieh Mohammadi Alashti, Afsaneh Fendereski, Reza Dehbandi,
Volume 16, Issue 4 (3-2024)
Abstract
Background and Objective: One of the main limitations of using compost is the possibility of heavy metals with high concentrations. Unlike organic contaminants, these elements resist decomposition by microorganisms and, when present at elevated levels, pose a toxicity risk to soil, plants, aquatic ecosystems, and human health.
Materials and Methods: This study was a descriptive cross-sectional study conducted in 2021-2022w. Samples were collected from three compost factories in Mazandaran (Babol, Behshahr, and Tonekabon) using random sampling methods and prepared according to the acid digestion method (National Standard Institute 5615). The concentration of heavy metals in the samples was measured using an ICP-OES.
Results: The average concentration of arsenic, zinc, lead, cadmium, cobalt, chromium, copper, and nickel in the analyzed samples were 1.38±3.47, 490±151.5, 74±12, 2.56±0.65, 4.5±1.46, 31.72±16.47, 186.11±49.9, 22.72±4.2 mg/kg dry weight of compost, respectively. The average concentration of heavy metals in different cities was compared using the Kruskal-Wallis test, based on which the concentration of heavy metals in none of the cities was significantly different from each other (p>0.05).
Conclusion: The concentration of heavy metals in the investigated compost samples was lower than the limits specified in both domestic and international standards. Therefore, the final product of the examined compost factories meets the health standards for heavy metals and is safe for use in environmental applications.
Sadegh Hosseinniaee, Mohammad Jafary, Ali Tavili, Salman Zare,
Volume 16, Issue 4 (3-2024)
Abstract
Background and Objective: The toxicity of heavy metals is one of the most important environmental issues in the current century. This research aimed to investigate the effect of municipal solid waste compost on the absorption of nutrients and lead and zinc metals in M. cuneatum and V. speciosum plants.
Materials and Methods: In a greenhouse experiment, compost at four levels (0, 1, 3 and 5% w/w) was completely mixed with natural soil contaminated with heavy metals (Pb and Zn). After six months of harvesting the plants, the shoot and root biomass was determined. Also, the concentration of macronutrients and micronutrients, Pb and Zn in the roots and aerial parts of plants and available Pb and Zn in the soil were measured using the ICP-OES. In order to investigate the correlation between the measured plant and soil parameters, principal component analysis (PCA) was performed
Results: Compost significantly improved the shoot dry weight of M. cuneatum and V. speciosum by 13 and 19%, respectively. 5% compost significantly reduced shoot lead by 64 and 34.4% in M. cuneatum and V. speciosum, respectively, compared to the control. Compost was more effective in increasing potassium, phosphorus, copper, and nickel than magnesium, manganese, and calcium, and increased shoot potassium by 22 and 32%, respectively, in M. cuneatum and V. speciosum compared to the control; this increase was 30 and 14% for copper and 19 and 21% for phosphorus, respectively. PCA analysis showed that, among the investigated elements, potassium, phosphorus and copper were most affected by composting and had the maximum role in improving plant growth and reducing lead toxicity.
Conclusion: Municipal solid waste compost improved the growth of M. cuneatum and V. speciosum and reduced phytotoxicity by immobilizing lead in the soil.
Safieh Hassanzad, Hossein Pirkharrati, Masoumeh Ahangari, Farrokh Asadzadeh,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: One of the significant challenges in mining areas is the pollution of the environment by heavy metals. Therefore, it is crucial to assess the pollution risk associated with mining wastes and take action to mitigate their environmental impact. The current study assessed the risk potential of recently deposited tailings in the Songun copper mining area.
Materials and Methods: Based on the conditions of tailings, 26 samples were randomly selected from the recently deposited mine wastes. Twenty-two thin and thin polished sections were prepared for lithology and mineralogy studies. Inductively-Coupled Plasma Mass Spectrometry (ICP-MS) was employed to analyze all 26 samples, while X-ray diffraction method (XRD) was used to analyze a subset of 10 samples.
Results: Sulfide minerals, as the main source of environmental pollution, remain intact and unaffected in the tailings. However, the majority of potentially toxic elements (PTEs) exhibit higher concentrations in the waste composition than the standard levels, resulting in a total ecological risk index of 49.93. Geochemical indicators highlight significant pollution levels for elements such as lead (Pb), arsenic (As), and copper (Cu). The values of the non-carcinogenic risk index for children (except As and Fe) and adults are lower than 1, indicating a non-significant non-carcinogenic health risk. However, the carcinogenicity index also indicates a significant carcinogenic risk in the case of long exposure to wastes, particularly for children.
Conclusion: Therefore, wastes pose a significant environmental risk potential, and due to this risk, proper management of their storage is necessary to prevent the release of PTEs into the environment.
Ehsan Manavipour, Akbar Eslami, Abbas Shahsavani, Ahmad Alahabadi, Reza Saeedi, Fatemeh Shokri Dariyan, Mehrnoosh Abtahi,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: In today's society, preparing healthy food has become challenging due to the variety of food production methods. Oil is produced in several ways in our country. In the cold pressing method, there is insufficient monitoring of the manufactured product. The aim of the present study is to investigate the physicochemical characteristics and the levels of heavy metals of industrial oil compared to cold-pressed oil.
Materials and Methods: In this research, 54 samples of sunflower, sesame, and canola oil produced by both cold pressing and industrial refiningmethods were prepared. Their physicochemical characteristics, including refractive index, acid value, iodine value, saponification value, peroxide value, anisidine value, as well as the concentrations of lead, iron, arsenic and copper were determined. Additionally, the effect of storage time on these characteristics was investigated.
Results: The Iodine number showed the highest deviation from the standard (61%), with an average of 136.70 gI/100g for the cold-pressed oil and 134.48 gI/100g for industrially refined oiland. The average value of the physicochemical characteristics, except for the saponification value, were higher in the cold-pressed oil samples compared to the industrially refined oil samples, but the observed difference was not statistically significant. An investigation into the effect of storage time on physicochemical properties revealed a significant increase in peroxide value (p<0.01) and anisidine (p <0.05) in both oil groups over a two-month period. The average concentration of arsenic, lead, iron and copper in the studied oils was 0.03, 0.78, 0.05 and 0.05 mg/kgoil, respectively. A deviation from the standard was observed only in one sample of cold-pressed sunflower oil, with an arsenic concentration of 0.11 mg/kgoil).
Conclusion: Based on the obtained results, the refined industrial oils exhibited more favorable chemical characteristics and stability. It is suggested that cold-pressed oils should be consumed within a short period of time. For frying purposes, refined industrial oils are preferable.
Abbas Khazaee, Mehrnoosh Abtahi, Mahsa Jahangiri-Rad, Fatemeh Shokri-Daryan, Mohammad Rafiee,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: Identifying the quality of non-conventional waters and exploring their optimal utilization are fundamental measures for maintaining public health. This study aims to investigate the effluent quality of the irrigation canals in Pakdasht farms.
Materials and Methods: In this cross-sectional descriptive study, 120 samples were collected from 6 irrigation canals in Pakdasht fields over a period of 5 months. The physicochemical and microbial characteristics of the canal effluents were determined based on the standard methods of water and wastewater tests. The concentration of heavy metals was measured using an ICP device. To determine the possibility of using the effluent of Pakdasht canals for agricultural purposes, the Environmental Protection Organization of Iran and FAO standards were used.
Results: The average concentrations of COD, BOD5, TSS, TDS, NO3-, SO4-2, PO4-3 parameters were 259, 125, 105, 697, 4.5, 94.4, 13.5 mg/L. Additionally, the average number of total and fecal coliforms in the effluent of the canals exceeded the standard values set by IRNDOE and FAO. The mean pH was 6.97, the electrical conductivity (EC) was 1014 μm/cm, and the turbidity was 76.2 NTU. The detected concentrations of heavy metals were awithin the following ranges: Cr (0.025-0.045 mg/L), Cd (0.0006-0.001 mg/L), Pb (0.0006-0.001 mg/L), Co (0.038-0.059 mg/L), and Ni (0.05-0.06 mg/L), which were roughly lower than the suggested standards. However, both HEI and WWQI indices confirmed that the water was unsuitable for agricultural irrigation.
Conclusion: Based on the comparison of the results of the parameters measured in this study with the environmental and FAO standards, the effluent from the irrigation canals of Pakdasht city is deemed unsuitable for the irrigation of warm-season crops but suitable for fodder and industrial crops.
Mohammad Fahiminia, Hossein Jafari Mansoorian, Akbar Eskandari, Amirhossein Karimpour Ardestani, Gharib Majidi, Samira Bahrami Valeh,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: Waste management as an inevitable byproduct is one of the most critical environmental issues in any society. Its management is essential for preventing environmental pollution. The aim of this research is to examine the management of production waste in the Azadi Sports Complex.
Materials and Methods: This research is a descriptive, cross-sectional, and empirical study that utilizies questionnaires, field visits, weight analysis, sampling, and determination of the physicochemical characteristics of waste. The questionnaire includes questions about the production rate, source reduction, separation, recycling, collection, storage location, transportation outside the complex, and final disposal of waste.
Results: The amount of waste generated from the Azadi Sports Complex was 449.87±4.83kg/day, with the highest waste production observed from the Wrestling Federation (95.37 kg/day) and the lowest from the Kung Fu Federation (12.75 kg/day) and the clinic (12 kg/day). The results of the physicochemical characteristics indicated that the average moisture content was 47%. Combustible materials accounted for 67% with a high calorific value of 12807 kcal/kg, and the ash content was 42%. The dry and wet wastes were collected daily, mixed together, and stored together in an enclosed area.
Conclusion: The results showed that the waste separation, recycling, and storage practices in the Azadi Sports Complex are unsatisfactory. Additionally, there is no existing program for waste reduction at the source or recycling. Therefore, the establishment of a proper waste management system to mitigate the waste volumes in this complex is necessary.
Hadi Niknejad, Fathollah Gholami-Borujeni, Khadijeh Sajjadpour, Samira Mojerlou, Reza Ghasemnejad, Mohammad Rafiee,
Volume 17, Issue 2 (9-2024)
Abstract
Background and Objective: Personal hygiene and adherence with health protocols in food preparation and distribution centers by operators are essential for controlling the transmission of infectious diseases. This study aimed to investigate the microbial contamination and compliance with health protocols among bakery workers in Mahmoudabad, Mazandaran, in 2020.
Materials and Methods: In a cross-sectional descriptive study, 149 samples were collected from the hands of workers in bakeries in Mahmoudabad. The microbial load was determined using the System Sure Plus device. Additionally, standard checklists, which included questions related to compliance with health protocols in the workplace, were used. The collected data was then analyzed using SPSS 26 software.
Results: Among the studied samples, 51.1%had a microbial load higher than 30 RLU (Relative Light Units), 28.86% had a microbial load of 10-30 RLU and 20.13% had a microbial load less than 10 RLU. Based on the results of the checklists, the rates of adherence to hand disinfection protocol, observance of social distancing, use of liquid soap, and use of a mask were 43.6%, 61.7%, 59.7%, and 53.7%, respectively. Additionally, data analysis revealed a significant relationship between business gown usage and microbial contamination on personnel's hands (p = 0.031).
Conclusion: Based on the results, it was evident that the workers' hand hygienewas in a concerning condition, posing a potential threat to their overall well-being. Therefore, individual health education and food safety practices should be improved, and inspections by environmental health monitors should be considered to ensure stricter public health standards.
Behnaz Abdollahinejad, Mahdi Farzadkia,
Volume 17, Issue 2 (9-2024)
Abstract
Background and Objective: Earthworms are important in soil formation. They maintain soil structure and fertility and can be used as indicators to evaluate various changes and impacts. Therefore, the present study was developed to investigate the effects of diesel pollutant on the population and survival of the earthworm species E.fetida in the co-vermicomposting process.
Materials and Methods: This experimental study was conducted over 90 days to investigate the effects of diesel concentration on the survival of E.fetida in the co-vermicomposting process. One kilogram of soil contaminated with diesel, vermicompost, and raw activated sludge was added to each reactor in a ratio of 0.25:0.35:1. 10. Additionally, 20 adult E. fetida were added to the reactors with diesel concentrations of 10 and 30 g/L after the adaptation process.
Results: The survival of earthworms and the formation of cocoons in reactor number 3 were higher than in other reactors. Additionally, the amount of diesel removal in reactor number 3 (diesel concentration: 10 g/kg dried soil +20 E.fetida) was higher (70.5%) compared to the other reactors.
Conclusion: The results of the study showed that earthworm reproduction is more sensitive than survival or weight change to higher concentrations of diesel-contaminated soil. The presence of petroleum compounds in the soil is harmful for the growth of E.fetida, and its acute effects on the production of earthworm cocoons were observed.
Hadi Niknejad, Nima Kalvani, Mehdi Seyedirad, Alireza Ala, Reza Saeedi, Mehrnoosh Abtahi, Fathollah Gholami-Borujeni,
Volume 17, Issue 2 (9-2024)
Abstract
Background and Objective: There have been concerns about microbial contamination along the coastal cities in the north of the country, particularly in cities of Mazandaran province, which could pose health risks for swimmers and tourists. The present study aimed to quantitatively assess the risk of gastrointestinal diseases resulting from exposure to E. coli and enterococci bacteria during recreational activities on the beaches of Fereydunkanar.
Materials and Methods: In this cross-sectional descriptive study, 66 grab samples collected during the summer were analyzed to investigate microbial contamination in the recreational beach waters of Fereydunkanar.The Monte Carlo simulation method was used to calculate both daily and annual infection risks.
Results: The findings demonstrated that transmission of enterococci was more likely than that of E. coli in the swimming areas of these beaches. The average annual infection risk for E. coli was 0.41 for adults and 0.69 for children . Additionally, the annual risk of enterococci infection was 1 for adults and 0.99 children and, which exceeds the range advised by the WHO and EPA. These findings indicate that children have a higher infection risk compared to adults.
Conclusion: Unrestricted discharge of municipal and industrial wastewater effluents into sea and rivers can contribute to the presence of harmful microbes in beaches. By implementing effective environmental and recreational management strategies, it is possible to minimize the risk of public health hazards at recreational beaches while also preserving the natural beauty of these important public spaces.
Sadaf Moeini, Seyed Masoud Monavari, Fariba Zamani Hargolani,
Volume 17, Issue 2 (9-2024)
Abstract
Background and Objective: The increase in waste at integrated urban waste centers, along with the problems and adverse environmental consequences due to their inappropriate establishment have become more apparent. This research was conducted with the aim of determining and investigating environmental pollution in urban waste integration management centers.
Materials and Methods: This research investigated the environmental pollutants in the integrated waste center in Koohak at various distances ranging from 0 to 900 meters. Four main criteria—waste, water pollution, air pollution and sound pollution—were determined, each with 16 sub-criteria. The map of each criterion and sub-criteria were multiplied by the coefficients they received from the weights obtained using the Analytical Network Process (ANP) method. By combining the criteria using the Weighted Linear Combination (WLC) method and superimposing them, finally, the studied area was ultimately classified into three classes: inappropriate, medium, and suitable.
Results: Air pollution, with a weight of 0.26, had the highest rating compared to the other three criteria. Noise pollution (0.25), water pollution (0.24) and waste-related criteria (0.23) were ranked next. The results of the Kruskal-Wallis test indicated a significant difference in pollutant concentrations between different stations (p<0.05). Additionally, the results show that the average concentration of pollutants at distances of 0-300 meters differed significantly from those at all other distances (p<0.05). After determining the suitable zones using the WLC method, the results showed that 62.5 percent of the criteria were approved by the environmental organization.
Conclusion: By examining the results of the methods used in this research, it can be concluded that the combination of ANP and WLC methods provide effectivee results. However, uncertainty in subjective decisions and time constraints in decision-making have posed challenges in assessing waste collection in integrated urban waste centers.
Ali Amoozadeh, Hamzeh Saghafi,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: In recent decades, the issue of crop product safety has led to develop methods for analyzing pollutants in crops. In the present study, ultra-trace amounts of lead (II) ions were measured in lettuce and water samples collected from Shahmirzad, located in Semnan province, an area known for its lead-containing mineral mines.
Materials and Methods: After sampling and pre-preparation, the lead content in each sample was extracted using solid phase extraction with modified silica gel. The recovery percentage of lead was then determined using atomic absorption spectroscopy.
Results: Optimization of key parameters such as pH, adsorbent amount, analyte flow rate, and volume resulted in a recovery rate of 104%. The experiments also demonstrated a very low limit of detection (LOD) of 1.14 ng/mL, a concentration factor of 250, high analyte selectivity of the adsorbent in the presence of interfering ions, and a high adsorbent capacity of 2.93 μg/g.
Conclusion: The evaluation of experimental data indicates that the current study provides a highly selective method that can be applied to the extraction and recovery of various analytes from different sample types.
Seyyed Shahram Naghibzadeh, Mazaher Moeinaddini, Mehdi Zafaranieh,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: Identiying the most optimal solution has long been an significant challenge for waste management decision-makers. This study aims to develop a decision support system to identify optimal environmental and economic scenarios for waste management.
Materials and Methods: This study presents the development and application of a decision support system that estimates the environmental burden and cost of waste using Life Cycle Assessment (LCA) and Life Cycle Cost (LCC) tools. The system then identifies optimal environmental and economic scenarios for waste management through a linear programming model. Data from the Karaj waste management system were utilized to apply and validate the decision support system.
Results: The outputs of the linear programming model in this system included one scenario based on minimizing environmental impacts and two scenarios based on minimizing costs imposed on the Karaj waste management system (MSWS). In both the environmental and second economic scenarios, incineration contributed the most to waste management, whereas composting was the dominant method in the first economic scenario. Additionally, recycling the maximum possible amount of recyclable materials was a common feature in all three scenarios, due to its environmental and economic benefits.
Conclusion: The result of this study demonstrate that the current Decision Support System can provide optimal environmental and economic scenarios for waste management to the decision-makers in the field. This is achieved by considering the inherent differences in the types of waste produced, the technologies employed, and the processing costs associated with each waste management system.
Gholamreza Shaghaghi, Amir Hossein Javid, Sara Allahyaribeik, Ali Mashinchian Moradi,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: The discharge of seawater concentrate from desalination plants into the sea causes irreparable effects on the environment. The purpose of this study is to identify the effects of this discharge, model methods for optimizing it, and design an effective outlet that minimizes environmental impacts and costs.
Materials and Methods: This study discusses impacts of seawater concentrate discharged into the sea, numerical modeling of diffusion, and outlet design based on discharge standards.A review of articles and sources from databases such as Google Scholar, Academia, Scopus, Civilica and Irandak was conducted using keywords such as “brine discharge”, “numerical modeling”, and “outlet design.” Out of 132 reviewed articles, 45 articles were consistent with the objectives of the study.
Results: The effects of seawater discharge can be observed in the discharge area and at greater distances. Numerical modeling is employed to predict pollutant concentrations at various distances and to determine the optimal discharge point while considering established standards. The design of the diffuser and the use of multiple nozzles at an angle of 60 degrees result in the greatest dilution at the discharge point.
Conclusion: The use of desalination systems necessitates addressing the effects of climate change. Appropriate modeling and design of the outlet are essential for complying with environmental standards and optimizing costs. Further research in this field is needed.
