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The Impact of Surfactant on Aquatic Ecosystems: A Study on Biochemical Alterations in Clarias gariepinus Induced with Linear Alkylbenzene Sulfonates
2024
Ikpesu, Thomas Ohwofasa
The toxicity of linear alkylbenzene sulfonates (LABs) to Clarias gariepinus was investigated. For 30 days, the fish were exposed to LABs at 0.00, 0.50, 1.00, 1.50, and 2.00 mg/L. After each trial period, one fish from each plastic tub was chosen and its heart was punctured for blood samples. The blood samples were then collected and deposited in pre-designated bottles for analysis. Following blood collection, a fish was dissected and its organs were extracted. The organs were preserved in liquid nitrogen at -25oC until they were analyzed. A portable refractometer was used to quantify total serum protein content. A microplate reader was used to measure reduced glutathione (GSH). Albumin was quantified using the Bromocresol Green albumin assay kit, whereas alanine aminotransferase activity was assessed colorimetrically. Subtracting albumin from protein concentration yielded the globulin content. On days 23 and 30, protein content corresponds positively with exposure length and differs significantly (p < 0.05) between the control and treatment groups. The activity of GSH reduced slightly but not significantly (p > 0.05). Significant variations in albumin and globulin (p < 0.05) only on day 30. AAS activity differs significantly (p < 0.05) between treatments and the control. This study demonstrated that LAB exposure can be harmful to human health. Because anthropogenic sources are the primary source of LAB exposure, authorities must implement strict mitigation measures to limit this risk.
Afficher plus [+] Moins [-]Investigating the spatial distribution of land surface temperature as related to air pollution level in Tehran metropolis
2023
Nasehi, Saeedeh | Yavari, Ahmadreza | Salehi, Esmael
Urban Heat Island (UHI) is a common urban problem associated with a wide variety of factors, including air pollution. This study investigated the relationship between Land Surface Temperature (LST) and air pollution as two spatial phenomena affecting urban areas. LST was estimated from OLI sensor images taken on 01/07/2020 using the single-channel algorithm. Air pollution was assumed to be indicated by the concentrations of NOX, NO2, NO, PM2.5 and SO2, which were obtained by Inverse Distance Weighting (IDW) interpolation from the data recorded on the same date as satellite images. Correlations were measured in terms of R and R2 and errors were estimated in terms of RMSE, MAE and MBE. The highest R and R2 were obtained for SO2 (20.89 and 45.99, respectively). The results showed that despite the high correlation between SO2 and LST, PM2.5 has a much better error distribution. Therefore, further research should be conducted on the relationship between these indices.
Afficher plus [+] Moins [-]Ionic Composition of Winter Atmospheric Precipitation in the Urban Area (South of West Siberia, Russia)
2023
Noskova, Tatiana | Lovtskaya, Olga | Panina, Maria | Ovcharenko, Elena | Papina, Tatyana
The work evaluates the urban snow cover pollution and determines the level of the city influence on the pollution of the urban atmosphere with major ions (ammonium, nitrite, nitrate, chloride, sulfate, phosphate, sodium, potassium, magnesium, calcium) during the winter period (on the case study of Barnaul city, 2014-2019). The priority ions that determine the high pollution of the urban atmosphere in winter are (nitrite, chloride, sodium), the sources of which are the exhaust of motor vehicles (nitrite) and the using of anti-ice reagents (chloride, sodium). The study showed an increase of the major ions in the urban snow cover (with the exception of nitrate ion) by more than two times compared with the regional and more than six times with the global natural background. To study the spatial features of the snow cover pollution interpolation surfaces of the spatial distribution of priority ions in the study area were constructed.
Afficher plus [+] Moins [-]Assessment of Environmental Hazard and Heavy Metal Contamination in Dhaleshwari River Sediment: A Toxicity based Study on Pollution
2023
Islam, Md. Al Sadikul | Hossain, Mohammad Enayet | Nahar, Kamrun | Majed, Nehreen
Developing nations, such as Bangladesh, face an enormous crisis in maintaining natural sustainability due to heavy metal contamination by the peripheral rivers. Frequent heavy metals discharged from tanneries, dyeing, and potential anthropogenic activities in Savar city pollute the Dhaleshwari river, which is an important river of the capital city, Dhaka. The present study aimed to assess the heavy metals contamination in the Dhaleshwari river sediment and evaluate the subsequent ecological risk indices emerging from the deposits. The contamination levels of heavy metals such as lead (Pb), cadmium (Cd), chromium (Cr), and nickel (Ni) were analyzed in the Dhaleshwari River sediment. Various environmental indices, such as Potential Enrichment Risk (PER), Geo-accumulation Index (Igeo), Enrichment factor (EF), Toxic unit analysis (TUs), etc., were observed in various compartments. The concentration of heavy metals ranged as follows: Lead (Pb), 297.3-414.6 mg/L; Cadmium (Cd), 1.5-4.4 mg/L; chromium (Cr), 97.9 -282.4 mg/L; Nickle (Ni), 85.1-264.5 mg/L; Iron (Fe), 11800-14375 mg/L. The metal concentrations were higher than the threshold effect level (TEL) and probable effect level (PEL) standards. Based on the TUs, the probability of toxicity is about 76% (TU > 2.3) at the Dhaleshwari river. Comparative evaluation of different environmental indices between present and past studies indicated progressive deterioration of sediments by heavy metals. Linear correlations of heavy metals in sediment samples demonstrated toxic accumulation of heavy metals in the surrounding ecosystem. The study outcomes emphasize the necessity of systematic investigation in the Dhaleshwari river and warranting effective prioritization to ensure river health over industrial wastewater discharge.
Afficher plus [+] Moins [-]Toxicological Effects of Simultaneous Exposure to Toluene and Noise on some Sexual and Stress Parameters in New Zealand White Rabbits
2023
Abouee-Mehrizi, Amirreza | Saed-Moucheshi, Shamseddin | Rasoulzadeh, Yahya | Mehdipour, Ahmad | Mohammadoghli-Reyhan, Fariba | Iraji, Zeynab | Alihemmati, Alireza | Shokoohi, Majid
Noise and toluene are among the numerous physical and chemical pollutants that can induce adverse effects on different body tissues and systems; nevertheless, most studies have only experimented the auditory changes induced by co-exposure to them. The present in-vivo study aimed to examine the endocrine effects of co-exposure to toluene and noise on the testes and adrenal glands. In this experimental study, 24 healthy male New Zealand White rabbits were used. The noise intensity was 100 dB (white noise) and the toluene concentration was 1000 ppm for two consecutive weeks. The luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, cortisol and adrenocorticotropic hormone (ACTH) were measured using the enzyme-linked immunosorbent assay (ELISA) method. The hematoxylin and eosin stain method (H&E) was performed for the histopathological analysis. Comparing different parameters in different groups on post-exposure days was carried out using GEE (generalized estimating equations) method. The results indicated that noise and toluene increased cortisol, LH and FSH levels during different days after the exposure. Exposure to toluene and noise made vacuolization and reduction of primary spermatogonial cells in the testes. Moreover, lymphocyte infiltration, congestion, swelling and vacuolization were detected in adrenal glands through exposure to toluene and noise. Toluene and noise induced different destructive effects on the endocrine system. More studies are required to elucidate other endocrine changes induced by exposure to toluene and noise.
Afficher plus [+] Moins [-]Greening of brick and tile production: an index to evaluate its environmental performance
2023
Oliveira, Leandro | Rebelato, Marcelo | Saran, Luciana
This work presents an index to evaluate the environmental performance of brick and tile manufacturing. The steps used were: 1) process study; 2) waste analysis; 3) determination of the potential impact of waste; 4) normalization of the potential impact; 5) comparative weighting among the potentials; 6) creation of the index. The index considers three parameters: the amount of waste produced, the disposal of waste, and the spatial dispersion of waste. The index was called CIRI (Ceramic Industry Rating Index) and was tested in a ceramic company. The field application showed that the waste that offered the highest environmental impact were gases generated from the burning of chips (30.850%), ashes generated from the burning of chips (30.483%), and steel drums (28.937%), which total of 90.27%. The CIRI index was 28.732%, which shows bad waste management. In view of the findings, two points must be considered: 1) the impacts generated by gaseous could be mitigated by companies by using technologies for drying tiles and bricks with a lower level of environmental impact; 2) entrepreneurs should be concerned about the fate given to the ashes because the dispose practiced is not environmentally correct. The index is useful for assessing the environmental impact of the brick and tile industry. It is useful for managers insofar as a proposal for process improvements. The novelty of this study lies in the index developed, which was designed to consider: the potential for environmental impact, the amount of waste, the spatial coverage, and the adequacy of waste disposal.
Afficher plus [+] Moins [-]Distribution of Natural Radionuclides and their Radiological Risks on Agricultural Soil Samples collected from Yemen
2023
Taher Hussien, Maher | Salaheldin, Ghada | Salaheldin Mohamed, Haby | Mansour, Howaida
The main objective of the current study is to determine the distributions of the specific radioactivity concentrations (226Ra, 232Th and 40K) from terrestrial sources using gamma spectroscopy system (HPGe-detector). Forty (40) agricultural soil samples were collected from Wadi Al-Hussini and Tuban in Yemen. The study locations are famous for exporting coffee all over the world. The average of radio-concentrations of 226Ra, 232Th and 40K were 61.95±11.57, 32.33±8.03 and 1045.17±153.47 Bq/kg for Wadi Al-Hussini and 65.20±11.59, 50.95±9.80 and 1078.13±157.57 Bq/kg for Tuban, respectively. The obtained results are higher than the average worldwide values reported by UNSCEAR. So, it is not acceptable with global safe criteria. Also, the radiation hazard parameters such as radium equivalent activity, absorbed gamma dose rate, outdoor and indoor annual effective dose equivalent, external and internal radiation hazard index, gamma index level, annual gonadal dose equivalent and excess lifetime cancer risk. All of these parameters are acceptable and within the worldwide values. The obtained results could be considered as reference data to follow up any changes in the future for natural radionuclides pollutants and their risks in the study area.
Afficher plus [+] Moins [-]Chemical Speciation, Bioavailability and Risk Assessments of Potentially Toxic Metals in Rainwaters as Indicators of Air Pollution
2023
Adegunwa, Abiodun | Adebiyi, Festus | Asubiojo, Olabode | Ore, Odunayo
Heavy metals contamination of rainwater is a function of the adsorbed metals present in the particulates of the atmosphere in which the rain was formed from and rainwater chemistry is an alternative way of monitoring urban air pollution for predominant metal species. Three distinct sampling sites (residential, industrial and commercial) were investigated in the south western part of Nigeria for one year. After acid digestion, quantification was done using a double-beam Atomic Absorption Spectrophotometer (AAS). The obtained results showed that heavy metals were predominantly present as free metal ion in the commercial and industrial areas but Mn and As mainly occurred in the suspended fraction. Residential area presented major fractions as bound to organic complexes except Cu and Cd which were principally available as suspended fraction. The health risks associated with the intake of the studied rainwaters indicated susceptibility to possible carcinogens upon consumption due to total RI > 10-4. Ecological risk assessment equally shown a very high level of ecological risks related with the metals due to RI ˃ 600. Sequel upon this, there is need for better sensitization of the citizenry to the sources and control of these pollutants.
Afficher plus [+] Moins [-]On-site Evaluation of NOx Removal Efficiency on Photocatalytic Pavements and Analysis of Environmental Variables
2023
Chun, Haejoon | Song, Min Young
The objective of this study was to identify the correlation between NOx concentration and envi-ronmental variables at photocatalytic concrete pavements containing TiO2 by direct monitoring in field. In order to confirm the NOx concentration according to various environmental variables of the photocatalytic concrete pavements, humidity, temperature, light intensity, and NOx concen-tration were measured continuously for 3 days at photocatalytic pavement, concrete pavement, and atmospheric conditions, respectively. We identified the NOx concentration at all measurement sites and calculated the NOx removal efficiency of the photocatalytic pavements. As a result, the NOx concentration of the photocatalytic pavement was 0.086 ppm on the 1st day, 0.125 ppm on the 2nd day, and 0.106 ppm on the 3rd day, which was mostly lower than that of the concrete pavement and the atmospheric conditions. When the NOx removal efficiency of the photocatalytic pavement on days 1–3 was examined by time, the NOx removal efficiency was evidently higher in the order of 0–6 h > 18–24 h or 6–12 h > 12–18 h for all three measurement days. In addition, the relationship between NOx removal efficiency and environmental variables was analyzed. As a result of corre-lation analysis between NOx removal efficiency and environmental variables of the site, relative humidity showed a positive (+) correlation, while temperature and light intensity showed a negative (-) correlation. Based on our results, we summarize some considerations for evaluating the NOx removal performance of photocatalytic pavements applied in the field.
Afficher plus [+] Moins [-]Characterization of Solid Waste Incineration Fly Ashes and their Heavy Metal Leaching Behavior
2023
Li, Yonglun | Chen, Weifang | Hu, Mingzhu
Two fly ashes from municipal solid waste incineration were selected to study their heavy metal leaching behavior. The main purpose of this research is to investigate the characteristics of fly ashes and compare the leaching of heavy metals in different leaching environment. pH and acid neutralization capacity analysis showed that fly ashes were highly alkaline. Fly ashes also contained a variety of heavy metals including Pb, Cu, Cr, Zn, Cd and Ni etc. Leaching studies showed that the alkalinity of fly ashes raised the pH of leaching solution from acidic to basic. Ni, Cu and Zn were strongly bound to ashes and manifested low leaching. In contrast, Cr and Cd had high mobility but their leaching was inhibited by the low solubility of carbonate Cr and Cd. Pb was highly leachable in the alkaline environment with concentration in the leaching solution reached as high as 9.74 mg/L. In addition, the presence of EDTA in the environment also increased leaching. Pb concentration was raised to 16.63 mg/L. This could be attributed to the chelating capacity of EDTA which means that the presence of organics in natural environment should be taken into consideration.
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