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Survey of silver nanoparticles (Ag-NPs) effects on blood indices of Rainbow trout (Oncorhynchus mykiss) juveniles Texto completo
2024
Mina Tavassoli Rudsari | Hamidreza Jamalzadeh | Elmira Mikaeili Agah
Silver nanoparticles (Ag-NPs) are potentially toxicant substances whose widespread use has raised considerations regarding environmental risks caused by the discharge of those nanoparticles (NPs) into aquatic ecosystems. The aim of this study was to analyze the impact of Ag-NPs on the hematologic parameters Rainbow trout, Oncorhynchus mykiss juvenile. Hematological toxicities of Ag-NPs to rainbow trout juveniles were assessed in four treatment groups: Control (without Ag-NPs), 0.1gr/L Ag-NPs solution (T1), 0.25gr/l Ag-NPs (T2) and 0.5gr/l Ag-NPs (T3). Blood samples were collected from fish after 5 and 10 days of exposure. Analysis of blood parameters in the 5th and 10th days of the experiment showed that the values white blood cells (WBCs) were higher in all treatments than those in the control group (p < /p>
Mostrar más [+] Menos [-]Effect of pollution on the ECO phytocenological assessment of Thymus caucasicus (Lamiaceae lindl.) populations in the territory of eastern Azerbaijan, Ardabil Texto completo
2024
Seyed Shiva Asbaghian Namin
Ecological and phytocenological assessments of 3 populations of Thymus caucasicus L. species were carried out in Ardabil. Classification of Th.caucasicus phytocenose on ecological groups were developed for the first time. In the result, the associations and their floristic composition and ecology were identified. Age, efficiency, aging indexes were appointed during cenological assessments of the Th.caucasicus formations. 3 natural cenopopulation of Th.caucasicus species were assessed, cenological situation studied in the territory, in 2013-2015 years and it was found that the 1st and 3rd populations were transition, 2nd was mature in 2013, in 2014, 1st was young, 2 nd and 3rd were mature, 1st and 2nd were young in 3rd was mature in 2015. Analysis of the parameters of population illustrated that restoration is higher in 1st and 2nd cenopopulation in 2015 rather than in 2013 - 2014.degradation of pasture to be casued that thymus population distrbution were significance decreased in the ardabil proviense.
Mostrar más [+] Menos [-]The Wastewater Quality of the Combined Cycle Power Plant of Montazer Ghaem for Re-using In Agriculture Texto completo
2024
Marjan Seyed Mousavi | Keivan Saeb
When the source of irrigation water is wastewater, then there are concerns about the pollution of crop products, the contact of farm workers with pathogens and environmental tensions on the farm''s surface. The purpose of this applied research was to investigate the quality of the wastewater of the combined cycle plant of Montazer Ghaem for re-using in agriculture. In this study, the characteristics of inlet wastewater and outlet effluent from the urban wastewater treatment plant of Montazer Ghaem were investigated based on the statistics of the period of operation and sampling. During the study, the effects of the medium âterm usage on the physical and chemical properties of the soil and several plants affected by this water were studied. For this purpose,three samples from the inlet wastewater and three samples of outlet effluents of the treatment plants were provided and 11 sewage quality parameters were tested. Also, three soil samples were prepared from 0 to 30 cm depths from adjacent lands under irrigation with wastewater and a control sample and their physical and chemical properties were determined. Analysis of the changes in the physicochemical parameters showed that, except for the pH which was approximately constant, all parameters including EC, TDS, COD, BOD, turbidity, fat, oil, heavy metals (Fe, Ni, Cr, Cd, Cu, V) in the inlet wastewater were decreased after refining and leaving the treatment plant. However, some of the parameters were higher than standard levels which indicate the improper performance of the refineries in the removal of physico-chemical contaminants
Mostrar más [+] Menos [-]The Impact of Environmental Education on The Environmental Behavior of Elementary School Students (Case Study: Students in Tehran) Texto completo
2024
Zaeimdar | Tavakoli | Lahijanian
The aim of this study is to evaluate the impact of environmental education on environmental change, environmental behavior of school students and elementary schools. The study conducted in Tehran. It is a cross-sectional study and to achieve the aim of the study a questionnaire consisting of 15 questions printed out. This is based on knowledge, attitudes and environmental behavior of students available to the study and presented to two groups of students; ordinary and green schools (8 schools) which constitute about 100 students from each schools. After checking the students' responses, the results of the analysis, were analyzed using SPSS software with the help of comparison test to two independent groups (T) and test comparing several independent groups (F) examined the research .The result revealed that between the two groups of green school students and ordinary ones, there are no significant difference (P> .05). This means that environmental education on behavior modified schools had little impact.
Mostrar más [+] Menos [-]Identify Ways to Reduce Noise Pollution in Aircraft Hangars Texto completo
2024
Bagheri | Razavian | Khoshmanesh
The noise pollution produced by various aircraft systems, including hydraulic, pneumatic, electrical systems and auxiliary aircraft equipment inside the aircraft hangars, generally cause hearing impairment and mental disorder of shift and office personnel. Identifying hangar noise pollutants can lead to find solutions and methods to deal with the contaminants in the aviation industry. In the first phase of the research, the sound study in each specified region of the hangar, the required measurements and frequency analysis are done to determine the type of sound control appropriate for the hangar. Measurements in this study were conducted in accordance with standards, and the results of the measurements and equilibrium calculations after recording were compared with the permissible exposure limits in accordance with the Occupational Exposure Limit values. The results show that the highest sound pressure level corresponds to sheet metal activities (128 dBC) and thereafter respectively, pneumatic systems (112 dBC), hydraulic pumps (104 dBC) and electrical systems (86 dBA), and found that noise pollution of the hangar during the specified time for shift and office personnel is higher than the permissible limits, and this exposure is harmful to the physical and mental health of the staff. In the second phase of the research, by the results of statistical analysis of the questionnaires, there was a significant relationship between the result of estimating noise intensity and the extent of its annoyance by shift and office personnel, which most people in the hangar believe that this level of noise pollution is very annoying.
Mostrar más [+] Menos [-]Evaluation of blood parameters changes of mice exposed to long-term Wi-Fi waves as a major environmental pollutant Texto completo
2024
Hamed Akbari | Lobat Taghavi | Seyed Kamal Eshagh Hossaini | Mohammad Gholami-Fesharaki | Seyed Alireza Hajiseyed Mirzahosseini
As the world entered the industrial era, the nature of environmental threats and dangers posed by technology also have gone through fundamental changes. One of these environmental pollutants is the propagation of waves with different wavelengths in the environment. In this study, we aimed to investigate the effect of 2.45 GHz microwaves on blood biomarkers of mice. In this study, 80 immature male BALB/c mice were used. According to the inclusion criteria, 72 mice were included in the study. Mice were divided into two groups (control group=24 mice, exposed group=48 mice). Exposed groups were divided into two subgroups of 24 (groups A and B). Subgroup A was exposed to a simple modem without antenna and subgroup B was exposed to a modem with two antennas. In the first phase of the study, mice were exposed daily for 60 minutes for 90 days and in the second phase for 8 hours daily for 90 days. Blood samples were taken on days 90 and 180. Data analysis was done by SPSS software version 25 (P value<0.05). This study shows that blood cells are affected by long-term exposure to Wi-Fi waves by decrease in number and volume. Furthermore, no significant difference was observed between the blood parameters of the two groups exposed to different modems which vary in the number of antennas. The results showed that the highest effect of Wi-Fi waves was on the following blood factors, respectively PLT, RBC, HCT, HGB, and WBC.
Mostrar más [+] Menos [-]Polycyclic aromatic hydrocarbons in street dust of Babylon City, Iraq: identification, quantification, and possible sources Texto completo
2024
Roa Mahdi Marmous | Atefeh Chamani
Polycyclic aromatic hydrocarbon compounds (PAHs) are stable organic isomers known for their carcinogenic, mutagenic, and teratogenic effects, making monitoring and quantifying their presence in the environment critically important. This study aimed to identify, quantify, and determine the origin of PAH compounds in street dust samples collected from Babylon City, Iraq in 2023. A total of 39 street dust samples were collected from 13 selected locations with three replicates. The analytes were extracted using the Soxhlet method, followed by identification and quantification using gas chromatography with mass spectrometry (GC-MS). Ten PAH compounds were identified in the dust samples, with a mean concentration of 19.5 mg/kg. The total concentration ranged from 4.19 to 123 mg/kg. Low molecular weight isomers accounted for 86.2% of the total PAH content. The mean levels of phenanthrene (PHE), fluoranthene (FULA), and pyrene (PYR) isomers were below the maximum levels set by the Dutch Ministry of Health, while other isomers did not statistically differ from the permissible limit. Dust pollution with PAHs was very high at 7 locations (>50.00 mg/kg) and high at the remaining 6 locations. Strong positive correlations were observed among all isomers at a significance level of 99%, and multivariate data analysis indicated pyrogenic sources as the origin of PAHs in the dust samples. Results suggest that gasoline combustion and mixed combustion are the primary sources of PAH dust pollution in the study area. Therefore, regular monitoring of PAH levels is recommended to mitigate associated risks in Babylon City, Iraq.
Mostrar más [+] Menos [-]Pb heavy metal monitoring using biological indicators, Prosopis juliflora, Eucalyptus microtheca and Ziziphus spina-christi in Ahvaz city (Iran) Texto completo
2024
Azadeh Ghorbani Talkhoncheh | Maryam Mohammadi Rouzbahani
Lead is one of the toxic and dangerous elements of the environment and has no biological role in the body of living organisms. Three plant species Prosopis juliflora, Eucalyptus microtheca and Ziziphus spina-christi were considered as investigated plants in Ahvaz city of Iran.The highest amount of lead in the unwashed leaf samples of Algaroba trees at the low traffic station was 72.56±0.01 mg kg-1. The lowest amount of lead in leaf samples related to washed leaves of Lotus trees in low traffic station was 60.13±0.25 mg kg-1. The pattern of lead accumulation in the washed and unwashed leaves of the studied trees in high traffic and low traffic areas was obtained as Algaroba>Eucalyptus>Lotusand in the vicinity of the gas station as Eucalyptus>Lotus>Algaroba. The highest and lowest concentrations of lead in the soil were obtained 40.4 mg kg-1 and 18.33 mg kg-1, respectively. The results of this study on the accumulation of lead in all species and stations showed that the accumulation of lead was more than the WHO limit of 2 mg kg-1. The BCF of the leaves of the Prosopis juliflora, Eucalyptus microtheca and Ziziphus spina-christi in Ahvaz city was higher than 1, so it can be concluded that these trees have the ability to accumulate lead in their leaves, and they can be classified as hyperaccumulator plants.
Mostrar más [+] Menos [-]Microplastics in feed affect the toxicokinetics of persistent halogenated pollutants in Atlantic salmon Texto completo
2024
Granby, Kit | Bhattarai, Bina | Johannsen, Ninna | Kotterman, Michiel J.J. | Sloth, Jens J. | Cederberg, Tommy Licht | Marques, António | Larsen, Bodil Katrine
Microplastics (MPs) are carriers of persistent organic pollutants (POPs). The influence of MPs on the toxicokinetics of POPs was investigated in a feeding experiment on Atlantic salmon (Salmo salar), in which fish were fed similar contaminant concentrations in feed with contaminants sorbed to MPs (Cont. MPs); feed with virgin MPs and contaminated feed (1:1), and feed with contaminants without MPs (Cont.). The results showed that the salmon fillets accumulated more POPs when fed with a diet where contaminants were sorbed to the MPs, despite the 125–250 μm size MPs themselves passing the intestines without absorption. Furthermore, depuration was significantly slower for several contaminants in fish fed the diet with POPs sorbed to the MPs. Modelled elimination coefficients and assimilation efficiencies of lipophilic chlorinated and brominated contaminants correlated with contaminant hydrophobicity (log Kow) within the diets and halogen classes. The more lipophilic the contaminant was, the higher was the transfer from feed to salmon fillet. The assimilation efficiency for the diet without MPs was 50–71% compared to 54–89% for the contaminated MPs diet. In addition, MPs caused a greater proportional uptake of higher molecular weight brominated congeners. In the present study, higher assimilation efficiencies and a significantly higher slope of assimilation efficiencies vs log Kow were found for the Cont. MPs diet (p = 0.029), indicating a proportionally higher uptake of higher-brominated congeners compared to the Cont. diet. Multiple variance analyses of elimination coefficients and assimilation efficiencies showed highly significant differences between the three diets for the chlorinated (p = 2E-06; 6E-04) and brominated (p = 5E-04; 4E-03) congeners and within their congeners. The perfluorinated POPs showed low assimilation efficiencies of 12%, which can be explained by faster eliminations corresponding to half-lives of 11–39 days, as well as a lower proportional distribution to the fillet, compared to e.g. the liver.
Mostrar más [+] Menos [-]Effects of LDPE and PBAT plastics on soil organic carbon and carbon-enzymes : A mesocosm experiment under field conditions Texto completo
2024
Jia, Xinkai | Yao, Yu | Tan, Gaowei | Xue, Sha | Liu, Mengjuan | Tang, Darrell W.S. | Geissen, Violette | Yang, Xiaomei
Although the effects of plastic residues on soil organic carbon (SOC) have been studied, variations in SOC and soil carbon-enzyme activities at different plant growth stages have been largely overlooked. There remains a knowledge gap on how various varieties of plastics affect SOC and carbon-enzyme activity dynamics during the different growing stages of plants. In this study, we conducted a mesocosm experiment under field conditions using low-density polyethylene and poly (butylene adipate-co-terephthalate) debris (LDPE-D and PBAT-D, 500–2000 μm (pieces), 0%, 0.05%, 0.1%, 0.2%, 0.5%, 1%, 2%), and low-density polyethylene microplastics (LDPE-M, 500–1000 μm (powder), 0%, 0.05%, 0.1%, 0.5%) to investigate SOC and C-enzyme activities (β-xylosidase, cellobiohydrolase, β-glucosidase) at the sowing, seedling, flowering and harvesting stages of soybean (Glycine Max). The results showed that SOC in the LDPE-D treatments significantly increased from the flowering to harvesting stage, by 12.69%–13.26% (p 0.05), but significantly decreased in the 0.05% and 0.1% LDPE-M treatments from the sowing to seedling stage (p 0.05). However, PBAT-D had no significant effect on SOC during the whole growing period. For C-enzyme activities, only LDPE-D treatments inhibited GH (17.22–38.56%), BG (46.7–66.53%) and CBH (13.19–23.16%), compared to treatment without plastic addition, from the flowering stage to harvesting stage. Meanwhile, C-enzyme activities and SOC responded nonmonotonically to plastic abundance and the impacts significantly varied among the growing stages, especially in treatments with PBAT-D (p 0.05). These risks to soil organic carbon cycling are likely mediated by the effects of plastic contamination and degradation soil microbe. These effects are sensitive to plastic characteristics such as type, size, and shape, which, in turn, affect the biogeochemical and mechanical interactions involving plastic particles. Therefore, further research on the interactions between plastic degradation processes and the soil microbial community may provide better mechanistic understanding the effect of plastic contamination on soil organic carbon cycling.
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