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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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]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.
Afficher plus [+] Moins [-]Phytoarchitecture Integrates Hybrid Onsite Phytosanitation to Suppress Building Environmental Pollution
2023
Samudro, Harida | Samudro, Ganjar | Mangkoedihardjo, Sarwoko
Efficiency of environmental resources is one of the goals of the sustainable development of a building and its sanitation. Sanitation efficiency was sought through hybrid offsite system, which was a decentralization of sanitation services. This study proposed a hybrid onsite system combining phytoarchitecture and phytosanitation, which empowers renewable building plants to improve resource efficiency, as well as sustainable building environmental health. Based on various empirical studies on sanitation management in rural and urban areas in many places, this retrospective study identified three wastewater disposal efficiencies. It was through quantity distribution, environmental media in which the greywater could be discharged, and quality treatment. The results marked the feasibility of wastewater services for greywater treatment, which served at least 75% of the wastewater quantity. Its main contribution was related to the distribution of discharge to all environmental media, and the improvement of the quality of greywater at its disposal. Building plants could be used for hybrid onsite system, thereby making these plants multifunctional to maintain the quality of the building environment. This hybrid onsite phytosanitation system covered various feasibility features compared to other existing systems. Implementation was flexible for new provisions and adaptation to existing systems for both urban and rural areas. Thus, the service maintained sustainable buildings and environmental health.
Afficher plus [+] Moins [-]Analysis of Heating Value of Hydro-Char Produced by Hydrothermal Carbonization of Cigarette Butts
2023
Tajfar, Iman | Pazoki, Maryam | Pazoki, Abolghasem | Nejatian, Niloofar | Amiri, Mohammadjavad
Hydrothermal carbonization is a thermal technique that offers numerous environmental benefits, particularly in managing solid waste streams by decomposing the raw materials of solid wastes and converting them into the renewable source of energy known as hydro-char. This study evaluates the heating value of hydro-char produced through the hydrothermal carbonization of cigarette butts, taking into account influential factors such as time, temperature, and pressure, as well as its benefits and economic implications, using a novel approach involving simulations aimed at reducing the number of required tests, saving time, and cutting costs.The range of 150 to 350 oC for temperature and 30 to 240 minutes for reaction time were considered and resulted in a thermal value range of 15.94 to 23.12 MJ/Kg for hydro-char, which makes its heat value greater than lignite coal and within the range of bituminous coal. The findings also indicated that temperature and time have a direct impact on the heat value, with time being the more influential factor, although high temperatures can expedite the reaction rate and should not be disregarded. Finally, the economic analysis of the project was conducted using the NPV method, which demonstrated that the viability of this method depends on the cost of coal, making it a promising alternative for accessing new and cost-effective fuel resources while considering environmental benefits. Besides, this study highlights the potential of hydrothermal carbonization as a viable and advantageous method for producing fuel resources from biomass and organic waste, and provides quantitative and comparable evidence of the applicability and benefits of the proposed hydrothermal carbonization methodology in comparison to conventional methods.
Afficher plus [+] Moins [-]Assessing the Effect of Environmental Stressors on the Community Structure of Macroinvertebrates and Water Quality of River Ugbalo, Nigeria
2023
Olusegun Olatunji, Emmanuel | Abubokhai Elakhame, Luckey | Catherine Osimen, Ekikhalo | Ovie Edegbene, Augustine
Aquatic macroinvertebrates play significant roles in the benthic zone of the aquatic ecosystem and they have different tolerance level to pollution. Globally, macroinvertebrates are usedas bioindicators in determining the ecological health and water quality status of aquatic ecosystem. Therefore, this study focused on the community structure of benthic macroinvertebrates in River Ugbalo, south-south Nigeria. Macroinvertebrates and physicochemical parameters were sampled in three marked out stations between March 2018 and February 2020. Physicochemical parameters were analyzed following standard procedures, while macroinvertebrates were collected with Kick net and Van Veen grab. Physicochemical parameters showed that the water quality of the three stations sampled were fair considering the values of pH, turbidity, sulphate, nitrate, phosphate, DO, BOD, and EC which were within the World Health Organization and Federal Environmental Protection Agency of Nigeria. Cluster analysis based on Bray- Curtis similarity showed that macroinvertebrates were clustered by stations rather than seasons. A total of 5,580 macroinvertebrates individuals were recorded showing high biodiversity in the river. Diptera was the most abundant Order with 2,488 individuals followed by Odonata with 697 individuals. The least represented Order was Lepidoptera with 13 individuals. The diversity indices showed that Margalef index (5.93), Simpson diversity (0.95), Evenness (0.63), and Shannon-Weiner index (3.30) were highest in Station 1. This research work showed that the water quality of the studied stations was fair and station 3 was the most perturbed station. We recommend the enactment and enforcement of policies that will lead to aquatic ecosystem restoration.
Afficher plus [+] Moins [-]Water Quality Status of Mangrove Ecosystem in Bedono, Sayung, Demak, Central Java
2023
Retnaningsih Soeprobowati, Tri | Jumari, Jumari | Wasiq Hidayat, Jafron | Muhammad, Fuad | Hanif Al Falah, Mirza | Kadek Dita Cahyani, Ni | Gell, Peter
Mangrove ecosystems have many functions for coastal areas, including ecological, social, and economic services. These functions have a systemic impact on the environment of other coastal ecosystems and human life. The mangrove ecosystem covering an area of 197.92 ha in Bedono, Demak Regency, Central Java was threatened due to the wave abrasion and high tides. Some parts of Bedono Village had become inundated and flooded permanently, zink as part of the ocean. This research was conducted to quantify water pollution in the mangrove ecosystem of Bedono Village using the Storage and Retrieval (STORET) method and the pollution index (PI). The fieldwork was conducted June 2022, by collecting water samples for laboratory analysis tests and in-situ water quality measurement. The parameter of the water quality that exceeded threshold of the Government Regulation of the Republic of Indonesia Number 22 of 2021 are the dissolved oxygen (DO) ranges between 4.39-8.78 mg L-1, BOD ranges between 30-32.4 mg L-1, phosphate ranges between 0.063-0.074 mg L-1, ammonia ranges between 0.148-0.48 mg L-1, Cr ranges between 0.071-0.21 mg L-1, and Pb ranges between 0.071-0.21 mg L-1. Based on the STORET method, the water quality in the mangrove ecosystem was found to be in the category of moderately (-16, for harbor function) – heavily polluted (-80, for tourism and -90, marine biota), whereas based on the PI index it was lightly polluted (1.77-4.12, for harbor function) – moderately polluted (11.06-13.83for tourism, and 9.96-11.85, marine biota).
Afficher plus [+] Moins [-]Reducing Environmental Pollutants by using Triorganotin(IV)-Tyrosine Complexes that Prolong the Life of the Polymers used in Outdoor Patios
2023
R. Arraq, Rafid | G. Hadi, Angham | S. Ahmed, Dina | Zainulabdeen, Khalid | Hashim, Hassan | A. Ahmed, Ahmed | M. Yusop, Rahimi | H. Jawad, Ali | A. Mohammed, Salam | Al-Amiery, Ahmed | Yousif, Emad
When exposed to UV light at ambient temperature, three tri organotin (IV) complexes with tyrosine as a ligand (85–97% yields) were utilized as additives to prevent the photo-degradation of PVC films (40 μm thickness). The compounds were described using NMR (1H, 13C and 119Sn), IR, and elemental analysis. The compounds formed were assigned trigonal bipyramidal geometry depending on the spectrum data. Several Triorganotin (IV) tyrosine complexes were synthesized and mixed with polymers to form thin films (vinyl chloride). Up to 300 hours of UV light (wavelength: 313 nm) exposure was given to these films. A microscope, atomic force microscopy, and scanning electron microscopy were used to examine the surface morphology of the PVC films. Rapid UV-weathering was employed to determine weight loss and the production of certain functional groups, including carbonyl and polyene. Compared to pure PVC film, the films with manufactured complexes showed less undesired alterations. By absorbing UV light and scavenging peroxides, hydrochlorides and radicals. The polymer was photo stabilized by the triorganotin (IV)-tyrosine complexes (vinyl chloride). It was discovered that Ph3SnL has the fastest rate of PVC photostabilization.
Afficher plus [+] Moins [-]Fuzzy Inference of Air Quality – A case study of Vadodara City
2023
Seema, Nihalani
Abstract: Air Quality Index (AQI) is derived from a series of observations of different air pollutants for reporting air quality. The severity of air pollution and its impacts on the general public are typically reported using the air quality index. Different methods have been developed by various regulatory agencies and scientists, to calculate the AQI using aggregation methods involving critical pollutants. This paper presents a comparison between conventional AQI and Fuzzy AQI. 20 sampling locations were chosen for Vadodara city in order to investigate the effects of urban air pollution, and ambient air quality was measured twice a week from October 2017 to February 2018. The Central Pollution Control Board (CPCB) method formulas were used to calculate the traditional Air Quality Index using the measured values of Coarse particulate matter (PM10), Sulphur dioxide (SO2), and Oxides of nitrogen (NOX). Additionally, the membership functions were provided as input to the Mamdani fuzzy inference system (FIS) for the fuzzy logic system, and the fuzzy air quality index (FAQI) was calculated. The computed conventional AQI values were compared with FAQI values. A close co-relation was observed between conventional AQI and fuzzy AQI values. The application of the fuzzy inference system demonstrates its capability to manage difficult issues including data ambiguity. The findings clearly show that the FIS is capable of resolving inherent discrepancies and interpreting complex conditions.
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