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Carcinogenic and Health Risk Assessment of Respiratory Exposure to BTEX Compounds in Gasoline Refueling Stations in Karaj – Iran
2023
Alimohammadi, Mehdi | Behbahaninia, Azita | Farahani, Maryam | Motahari, Saeed
BTEX is one of the common compounds in the breathing air of gas station workers, which can cause high carcinogenic and health risks. The present study was conducted to assess the carcinogenic and health risks of occupational exposure to BTEX compounds in gasoline fuel distribution stations in Karaj. This descriptive and cross-sectional study was conducted to assess the carcinogenic and health risks caused by exposure to BTEX compounds in 2021 during the summer and winter in six fuel distribution stations in Karaj. Occupational exposure to BTEX was measured according to the NIOSH 1501 method. Cancer and non-cancer risk assessment were performed according to the United States Environmental Protection Agency (USEPA) method. Data were analyzed in SPSS software version 26. The average occupational exposure to benzene, toluene, ethyl benzene, and xylene during a work shift among all participants in summer and winter were 83.33 - 89.33, 202 - 210.66, 126.55 - 136.83, and 168.81 - 174.83 µg.m-3, respectively. The highest concentration of BTEX compounds was observed in Gas station in the center of the city. The mean carcinogenic risk value of benzene and ethylbenzene were 139×10-2 and 27×10-2, respectively. The highest carcinogenic risk value due to exposure to benzene and ethyl benzene was observed in Gas station in the center of the city. The mean non-carcinogenic and health risks of occupational exposure to benzene, toluene, ethyl benzene, and xylene were 173.79, 14.19, 3.61, and 12.87, respectively. The findings demonstrated the values of carcinogenic and non-carcinogenic risk in the majority of participants were within the definitive and unacceptable risk levels. Therefore, corrective measures are necessary to protect the employees from the non-cancer and cancer risks.
显示更多 [+] 显示较少 [-]Role of Salinity and Oxidation-Reduction Potential in Mobility of Heavy Metals in Suspended Sediments at Estuarine Zone
2023
Jahanirad, Mina | Nasrabadi, Touraj | Karbassi, Abdolreza
Effect of salinity and oxidation-reduction potential (ORP) in the mobility of metals bound to suspended sediments at estuarine zone is investigated. Saline and freshwater samples as well as suspended sediments from estuarine zone of the Chalus River and the Caspian Sea, have been collected. Two series of four aquaria sets (natural and ORP-augmented conditions) containing turbid water with salinities of 0.25, 0.75, 1.5 and 2.5 psu were arranged. An increasing pattern of exchangeable-phase of all studied metals contents (at higher salinities) was observed under natural and ORP-modified conditions. Furthermore, the exchangeable-phase metal contents under ORP-modified conditions are higher (or equal) when compared with natural conditions. The overall trend of metals mobility potential might be evaluated as: Cd > Pb > Mn > Cu > Zn > Co > Ni. Findings of this research confirm the direct effect of both salinity and ORP parameters in mobility of metals bound to suspended particles in estuarine zones.
显示更多 [+] 显示较少 [-]Prediction of Air Pollutants Concentration Emitted from Kirkuk Cement Plant Based on Deep Learning and Gaussian Equation Outputs
2023
Ajaj, Qayssar | Mohd Shafri, Helmi Zulhaidi | Ramli, Mohammad | Wayayok, Aimrun
Researchers are interested in developing techniques to monitor, manage and predict the risks of gases and particles emitted from cement factories, which have a direct and negative impact on human health. Deep learning (DL) is a critical component of data mining, which further involves statistics and prediction. In this study, we developed a deep learning prediction model called the Deep Pollutant Prediction Model (DPPM). The data used for DPPM are separated into two types: observed data from a pollution monitoring station of the Institute of Mental Health in Ahmedabad City, India coded as (GJ001), to validate the model and simulated data generated using the Gaussian Plume Model for the hypothetical receptor (Laylan District, Kirkuk, Iraq) to predict the pollution that emitted from Kirkuk Cement Plant 5 km apart from the study area. The findings indicated that the DPPM has high efficiency in both Allahabad and Laylan stations, with more closed results for the data in the Laylan station, which is based on the Gaussian equation simulated data. Since the highest loss function value in the Laylan is 0.0221 of the CaO parameter, while it is 4.466 of the AQI parameter for the Allahabad Station, and the smallest loss function value in the Laylan is equal to 0.0041of both Fe2O3 and MgO parameters, it corresponds to 0.038 of Xylene for the Allahabad station. The results of the study proved that data continuity and non-volatility produce excellent outcomes for DPPM.
显示更多 [+] 显示较少 [-]Uranium in Groundwater: Distribution and Plausible Chemo-Radiological Health Risks Owing to the Long-term Consumption of Groundwater of Panchkula, Haryana, India
2023
Tanwer, Naresh | Anand, Poonam | Batra, Neha | Kant, Krishan | Gautam, Yogender | Sahoo, Sunil
A comprehensive investigation was engaged to determine the spatial distribution of Uranium (U) and the consequential chemical and radiological health risk associated due to the consumption of groundwater containing U, in Panchkula district. A well-accepted technique of fluorescence of U estimation in an aqueous medium was employed having a detection limit of 0.50 µgL-1. The chemo-radiological health risk and water quality index was computed using a standard equation of concerned agencies to determine the suitability for human health. The concentration of U was observed to vary from 1.70 – 12.28 µgL-1 with the mean value of 5.89 µgL-1 The concentration of U was far below the standard prescribed limits as per World Health Organisation, Atomic Energy Regulatory Board, and United Nation Environmental Protection Agency. Except nitrate and total alkalinity in few samples, all water quality paramters were within the recommended limit of BIS. The annual effective dose (AED), excess cancer risk (ECR), and lifetime average daily dose (LADD) indicated no potential health issue due to the consumption of groundwater of studied locations. The correlation was computed between U and various macro-anions and cations present in water samples. U was observed to have a significant weak positive correlation with total dissolved solids (TDS), electrical conductivity (EC), and salinity.
显示更多 [+] 显示较少 [-]Recycling Polyethylene Terephthalate for use in Structural Concrete with Natural River Aggregates
2023
Huaquisto-Caceres, Samuel | Quenta-Flores, Darwin | Flores-Quispe, Eduardo Luis
Polyethylene terephthalate (PET) is one of the most common types of plastic waste found in municipal waste and has a negative impact on the environment, recycling and its use in concrete is an alternative solution to address these problems. The objective of the study was to evaluate the physical-mechanical behavior of hydraulic concrete with additions of PET plastic bottle fibers and natural river aggregates. The concrete was evaluated in its fresh state by means of the Slump and in its hardened state by means of density and compressive and flexural strengths, for which cylindrical and prismatic specimens were prepared with PET fibers at proportions of 2%, 4%, 6% and 8% by weight of cement plus the standard concrete designed for 21 MPa. It was found that the slump and density of the concrete decreased with additions of PET fibers. The 28-day compressive and flexural strengths increased to optimum values of 22.79 MPa and 3.19 MPa at 2% and 6% PET fibers, respectively. It is concluded that the viable application of 2 mm by 30 mm PET fibers in concrete is at 4% with dosages of 15.78 kg/m3 added to the standard concrete for structural elements subjected to compression and flexure with sustainable production at low cost.
显示更多 [+] 显示较少 [-]Natural Extraction of Dyes from Saffron ‘Crocus sativus L’ Flower Waste, Cotton Dyeing, and Antioxidant Effectiveness
2023
Lachguer, Khadija | Boudadi, Imane | Fayzi, Lahbib | El Merzougui, Soumaya | El Bouchti, Mehdi | Cherkaoui, Omar | Serghini, Mohammed Amine
The production of saffron, the spice obtained from the dried stigmas of Crocus sativus L. (Iridaceae family) flowers, generates, after pruning, considerable quantities of waste containing natural dyes. Saffron flower waste could be a source of extraction of natural dyes with antioxidant activity. In this study, we investigate the possibility of using saffron flower waste for dyeing cotton and evaluating the antioxidant effect of this dye by the DPPH free radical, reducing power and β-carotene bleaching assay. The dye has been evaluated for the composition of the color by the UV-visible spectrum and tested for the dyeing of cotton. The results indicate the presence of polyphenols and flavonoids. The dyeing conditions have been optimized at 6% dye concentration, dye bath pH of 3, dyeing temperature at 98 °C and dyeing time of 60 min. 2% dye concentration with 5 to 10% mordant concentration remains sufficient for dyeing with pre-mordanting. The exhaustion of the bath after dyeing has been improved by a rate of 20% in the case of addition of mordants which have produced a shade of green color. The dye contributes to the significant antioxidant activities with more DPPH scavenging capacity, FRAP reducing power, and β-carotene bleaching inhibition. Cotton fabrics dyed with bio-dyes obtained from saffron flower waste show good color fastness properties and could be a potential source of natural antioxidant agent. It presents an important eco-friendly alternative to synthetic dyes for large-scale application in textile and food industries.
显示更多 [+] 显示较少 [-]Contamination Levels, Source Apportionments, and Health Risks Evaluation of Heavy Metals from the Surface Water of the Riruwai Mining Area, North-Western Nigeria
2023
Badamasi, Hamza | Olusola, Johnson | Durodola, Solomon | Akeremale, Olaniran | Ore, Odunayo | Bayode, Ajibola
Mining is one of the most environmentally damaging human activities, having long-term health effects on humans. In this research, the levels of contamination, source distribution, and health risks of heavy metals to residents from drinking surface water near Riruwai mining sites were investigated. The findings of the study indicated that the heavy metal levels ranged from As (0.00–0.04 mg/L), Cd (0.00–0.04 mg/L), Cr (0.02–0.06 mg/L), Mn (0.02–0.07 mg/L), and Pb (0.00–0.05 mg/L), with mean levels of 0.02, 0.013, 0.03, 0.02, and 0.04 mg/L, respectively. The concentrations of all metals, with the exception of Mn and Cr, are higher than acceptable limits. The values of the heavy metal pollution index (HPI) for all the metals, with the exception of Mn, exceed the threshold limit of 100, indicating serious pollution of the surface water. This was confirmed by the results of Nemerow’s pollution index (NPI). Multivariable analysis revealed anthropogenic and natural sources as the main sources of heavy metal contamination, with Cd, As, Cr, and Pb originating from mining activities and Mn possibly coming from parent materials. The total hazard index (HI) and non-cancer risk (HQ) values in children and adults are within acceptable limits. However, the total life cancer risks (TLCR) of As and Cd were higher than the tolerable limit of 1.00E-06. Therefore, heavy metals in surface water, particularly As, Cd, and Pb, should be properly monitored and a treatment program implemented to safeguard the health of local residents, especially children.
显示更多 [+] 显示较少 [-]Response Surface Methodology for Adsorption of Humic Acid by Polyetheretherketone/ Polyvinylalcohol Nanocomposite Modified with Zinc Oxide Nanoparticles from Industrial Wastewater
2023
Pournamdari, Elham
The applicability of Polyetheretherketone/Polyvinylalcohol Nanocomposite Modified with Zinc Oxide Nanoparticles synthesized for eliminating humic acid rapidly from industrial wastewater. Identical techniques, including BET, FTIR, XRD, and SEM have been utilized to characterize this novel material. Also, the impacts of variables including initial humic acids (HAs) concentration (X1), pH (X2), adsorbent dosage (X3), and sonication time (X4) came under scrutiny using central composite design (CCD) under response surface methodology (RSM). The values of 10 mgL-1, 6.0, 0.025 g, and 5.0 min were investigated through batch experiments, considered as the ideal values for humic acids (HAs) concentration, pH, adsorbent dosage, and contact time, respectively. Adsorption equilibrium and kinetic data were fitted with the Langmuir monolayer isotherm model and pseudo-second-order kinetics (R2: 0.999) with maximum adsorption capacity (102.0 mgg-1), respectively. The overall results confirmed that Polyetheretherketone/Polyvinylalcohol Nanocomposite Modified with Zinc Oxide Nanoparticles could be a promising adsorbent material for humic acids (HAs) removal from industrial wastewater.
显示更多 [+] 显示较少 [-]Assessment of Microplastic Pollution Sources in the Coastal Recreational Zones
2023
Silakov, Mikhail | Sibirtsova, Elena | Temnykh, Alexandra
The authors propose a methodology for assessing the sources of microplastic pollution (particles 0.5-5 mm in size), which makes it possible to differentiate coastal recreational areas according to the degree of vulnerability to microplastic accumulation. The methodology takes into account the sources of microplastics coming to the beach directly from vacationers - factors of recreational activities, as well as the influence of factors of the adjacent territory: the type of adjacent territory, saturation with transport infrastructure, etc. An analysis of the results of monitoring the microplastic concentration in beach and bottom sediments of seven beaches of the Sevastopol region with varying degrees of anthropogenic load during 2018–2020, as well as an assessment of the sources of microplastic pollution on these beaches using the proposed methodology, made it possible to differentiate these coastal recreational areas according to the degree of vulnerability to accumulation of microplastic pollution. The most vulnerable are the beaches that are actively visited by tourists and located in close proximity to large blocks of apartment buildings and extensive transport infrastructure (Pesochniy and Omega). The beaches Konstantinovsky and Goryachka (placed close tothe thermal power station), located in the zone of active navigation of ships of various tonnage, are confined to areas of low and moderate pollution. The main stream of vacationers on them are local residents with a high turnover rate. The least vulnerable are the beaches with park areas: Uchkuevka, Solnechny and Zolotoy. The source of microplastic pollution on these beaches is mainly vacationers.
显示更多 [+] 显示较少 [-]Trichoderma tomentosum Ts141 as a Potential Candidate for Bioremediation of Cadmium, Lead, and Nickel Ions
2023
Hosseinzadeh, Samira | Aliloo, Ali Asghar | Shahabivand, Saleh | Ghaderi, Mohammad
Fungi are successful microorganisms in the bioremediation of environmental pollution. So, this study aimed to determine the potential of Trichoderma tomentosum to remediate cadmium, lead, and nickel contaminations from potato dextrose agar (PDA) and potato dextrose broth (PDB) media. Growth rates, toxicity tolerance sporulation, bio-sorption capacity, and bio-sorption efficiency of the fungus were evaluated under different concentrations of CdCl2, Pb(NO3)2, and NiCl2. The findings demonstrated that the growth rate of the fungus differed depending on concentration, metal type, and medium. More metals in PDA medium induced more inhibition on fungus growth rates; however, the rate was independent from the heavy metals concentrations in PDB medium. Cadmium was the most toxic metal tested against T. tomentosum, with a 72h LC50 of 37 ppm. It was about 3.16 and 4.24 times as toxic as nickel and lead, respectively. In the control condition, sporulation of the fungus began at 72 hours, but under the heavy metals, it began at 168, 168, and 192 hours, respectively, for Pb, Ni, and Cd. Both the bio-sorption capacity and efficacy of the fungus were significantly enhanced by an increase in metal content and the highest values were obtained at 200 ppm of the salts. The heavy metals total bio-sorption capacity order was Ni < Cd < Pb in the aqueous medium. The conclusion was that T. tomentosum has a greater potential for the biosorption of heavy metals; hence, the fungus may be employed for the bioremediation of heavy metals from polluted sites, particularly wastewater and industrial influents.
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