Journal of hazardous materials advances最新文献

Graphene oxide-based nickel-iron superparamagnetic nanoadsorbent (GO/Ni-Fe) was synthesized from electronic waste to effectively remove doxycycline (DXC) in aqueous media. The GO/Ni-Fe nanoadsorbent has been characterized using a number of instrumental techniques, including X-ray diffractometer, Zeta potential, Fourier transform infrared spectroscopy, elemental analyzer, vibrating sample magnetometer, transmission electron microscopy, energy dispersive x-ray, and X-ray photoelectron spectroscopy. These techniques showed that nickel-iron (Ni-Fe) nanoparticles with an average size of 4.26 nm were successfully fabricated on GO surfaces. The batch experiments were conducted under different conditions, including contact time, adsorption dosage, pH, concentration, and temperature, to determine the optimal conditions of the adsorption process. The maximum adsorption (90% removal) was established within 20 min, while the adsorbent dose was only 0.1 g/L at pH 5. The adsorption process was best fitted with the pseudo-second-order model, which suggests the interaction of doxycycline with the GO/Ni-Fe nanoadsorbent is mainly controlled by the chemisorption process. This may be due to hydrogen bonding as well as electrostatic interaction and π-π interaction between adsorbates and adsorbents. The isotherm data of the adsorption process was best fitted with Langmuir isotherm model with a maximum adsorption capacity of 13.02 mg g ^{− 1} at 25 °C, indicating that the adsorption is a monolayer adsorption to heterogeneous surfaces with electrostatic interaction. The superparamagnetic properties of GO/Ni-Fe nanoadsorbent can be easily separated by external magnetic field and regenerated with methanol washing. The findings unambiguously demonstrated that magnetically separable GO/Ni-Fe nanoadsorbent could be a good choice to remove DXC from wastewater sources.

We present a methodology and the first tests to estimate the settling velocity of airborne microplastics based on wind tunnel experiments. A novel approach and original perspective are proposed, discussing in detail challenges and faced problems, both on the theoretical and experimental sides. Several experiments were performed, releasing fragments of different microplastic types, PET, PVC and LPDE. A statistical analysis was applied to the measurements and the values of the settling velocities were estimated to range between 0.1 and 0.2 ms${}^{-1}$, in agreement with most values found in the related literature. Based on the observed velocities, the applicability of the Stokes’ law, which is often used also for airborne microplastics, is then addressed, highlighting its potential limitations in the context of the microplastic dynamics in the atmosphere. We confirm that using the Stokes’ law may lead to a substantial overestimation of the settling velocity for the airborne microplastics. We also recommend to consider moving to the concept of ‘effective deposition velocity’, to account for the turbulent processes characterising the real atmosphere.

The mass concentration of diesel particulate matter (DPM) and its elemental constituents (twenty-four) emitted from stationary diesel engine exhaust at ten different sizes (56 nm to 18 µm) increased with rise in engine-operating load. The maximum value of DPM concentration varied from 10.3 ± 2.4 mg/Nm³ at 0 % load to 20.4 ± 6.5 mg/Nm³ at 100 % load at size-bin of 0.10–0.18 μm. The elements of S, Ca, K, Al, Na, Mg, Fe, and Zn contributed as the major components to DPM mass with more than 90 % to total elements at six engine-operating loads. Ca, K, Al, Na, and Mg also showed higher values of EFs compared to Fe, Zn, As, Cr and Ni. Compared to Cu, Mn, Co, Se, Pb, Ba, Sr, fuel-based emission factor (EF) of Ti, Ga, Cd, Bi, and Te showed lower side of the estimated values. The levels of hazardous particulate elements generated from stationary diesel engine exhausts was a matter of concern from human health point of view as these elements showed better potential in causing significant cancer and non-cancer diseases through long-term exposure. The elements in DPM revealed significant deposition in the pulmonary and alveolar region of the human respiratory tract.

Water pollution caused by chromium released from tannery is a serious concern to the environment and public health. Chromium removal from tannery effluent is a crying need before discharging to the surface water. In this study, acrylic acid-grafted sawdust was prepared by Tectona grandis sawdust grafting with acrylic acid employing gamma irradiation in the presence of air and Mohr's salt. It was treated with NaOH and the characterization of surface morphology and functional groups of modified sawdust was studied by SEM and FTIR.. The effects of solution pH, adsorbent dosage, adsorption time, and initial Cr(III) ion concentration were investigated by batch sorption studies. The process was found to be pH, temperature and concentration dependent. Langmuir and Freundlich isotherms were applied to realize the adsorption process in depth, and it was found that the Langmuir isotherm model fitted well with experimental data (R² value of 0.983). The maximum monolayer adsorption capacity of acrylic acid-grafted sawdust for Cr(III) from aquous solution was found to be 21.55 mg g^-1 at 25 °C. Pseudo-first-order and pseudo-second-order kinetic models were employed to analyze the kinetics of the process, and it was found that the experimental process followed the pseudo-second-order kinetic model, i.e. chemisorption. This study revealed that acrylic acid-grafted sawdust has a decent potential for the removal of Cr(III) from tannery effluents.

In recent years, the escalating concerns surrounding the pervasive presence of microplastics in the environment had prompted a pressing need to evaluate their potential impacts on ecosystems and human health. This study investigates the pathways and implications of microplastic intake through poultry product consumption by focusing on environmental toxicity and human health risks. Through an integrated approach encompassing available experimental data and literature synthesis, the intricate mechanisms of microplastic transfer from poultry feed to animal tissues are elucidated by highlighting the potential environmental implications of such contamination. An in-depth toxicological assessment evaluated the health risks associated with microplastic ingestion with poultry food consumption by emphasizing the acute and chronic effects on human well-being. This study emphasizes the urgency of implementing informed policy decisions and sustainable practices to mitigate the environmental and human health risks posed by microplastic contamination in the poultry food chain. The insights provided by this study serve as a foundational basis for generating awareness and implementing effective measures aimed at safeguarding both environmental integrity and human well-being from the escalating threats of microplastic pollution.

Background

Influenza represents a global One Health concern, and the utilization of nanoparticle-based vaccines or drugs emerges as a promising solution for its prevention and treatment. Nanoparticles, with their precision in drug distribution, heightened efficacy, and minimized adverse effects, have garnered attention as viable candidates in the fight against influenza. This meta-analysis assesses the effectiveness, safety, and potential applications of nanoparticles, particularly those incorporating natural compounds like curcumin, in influenza prevention and treatment.

Methods

A systematic literature search was conducted to gather and examine studies focusing on nanoparticle-based strategies for influenza prevention and treatment, with a specific emphasis on natural compounds such as curcumin. The results obtained were meticulously evaluated.

Findings

The results indicate that nanoparticles significantly enhance the effectiveness of influenza prevention. In animal models, nanoparticle interventions exhibit heightened antiviral activity, leading to a substantial reduction in viral load and improved survival rates. The precision of drug administration enabled by nanoparticles facilitates higher drug concentrations at the infection site, maximizing therapeutic benefits. Notably, nanoparticle-based therapies exhibit superior safety profiles compared to traditional antiviral medications, with minimal cytotoxicity and fewer side effects. The combination of phytochemicals with nanoparticles offers a promising avenue for influenza treatment, providing durable therapeutic alternatives with inherent natural qualities that enhance antiviral activity. The synergistic effect of phytochemicals and nanoparticles opens new avenues for the development of antiviral agents.

Conclusion

In conclusion, nanoparticles demonstrate both efficacy and safety in the treatment of influenza, acting as potent therapeutic agents due to their targeted drug delivery and enhanced antiviral activities. The inclusion of phytochemicals further amplifies their potential. Future research endeavours should focus on refining nanoparticle formulations, elucidating their mechanisms of action, and exploring innovative combinatorial strategies. The revolutionary impact of nanoparticles in influenza treatment holds the promise of advancing antiviral medicines and ultimately improving patient outcomes.

The risk assessment of PAHs in settled indoor dusts from different localities of Awka, Ekwulobia, and Rumuodomaya–Ogale, Eastern Nigeria, were investigated. Settled dust samples (n = 144) were collected from the windows and floor using brush and analyzed for PAHs with GC- FID. Dust from the windows showed higher total PAHs concentrations than the floor in the order; Rumuodomaya–Ogale > Ekwulobia > Awka. The 3- and 4-ring PAHs were dominant in the window and floor dust of Awka in all the months, while the 3-ring PAHs were the dominant compound in Ekwulobia. The concentrations of total PAH in the window and floor dusts of Ekwulobia, showed a significant difference across the months (p < 0.05). In Rumuodomaya–Ogale, the 3, 4, and 5-ring PAHs supersede in the window and floor dust. This showed that dust is a major sink for 3–5-ring PAHs. The compounds; BaA, DahA, Ant, BaP, and DBA were the major contributors to benzo(a)pyrene as toxicity equivalence ($Ba{P}_{TEQ}$) values of the window and floor dust. The total incremental life cancer risk was < 1.0 × 10⁻⁰⁴ in all the study area; hence, the increased indoor activities during COVID-19 lockdown had no significant cancer effect on human health of the populace.

The current study comprehensively reviews the ecological niche and pathogenicity shift in the freshwater microbial community in response to the stress induced by a high pollution load. The study provides a unique understanding of how a change in oxygen level tends to affect the survival of aquatic biota by delving into how an increase in pollutant load affects freshwater stability. The review indicated that high pollution loads alter the balance of freshwater resources such as organic matter, dissolved gases, light penetration, and essential nutrients. This causes oxygen dynamics and a species-dependent change in the community and niche of microorganisms in freshwater environments. This oxygen dynamics also causes the alteration of the genome of freshwater microorganisms, leading to the development of antibiotic resistance genes and thereby increasing the pathogenicity of freshwater microorganisms. The oxygen dynamic created lowers the natural defence strategies of the freshwater environment, thereby increasing the efficacy of the pathogens to infest the respective host. A detailed study of the mechanisms involved in freshwater exotoxins production and interaction with microorganisms will give an important insight into the niche shift in response to the effect of the exotoxin. The effect of the change in the pathogenicity of freshwater microorganisms is of importance to both environmental and medical interests. This is because the change in pathogenicity is not only detrimental to aquatic organisms but also resists improperly treated drinking water. Such water could retrogress wellness and quality of life when used continuously. An extensive study on how specific pollutants cause a shift in the niche and pathogenicity of freshwater microbiota will provide a detailed understanding of the impact of pollution on the stability of freshwater environment.

Industry is the main source of soil pollution in Jordan, where higher concentrations of potentially toxic elements were found in the soil around industrial estates. This study is dealing with an industrial pollution hot spot that is a steel factory in central Jordan that emits various ashes and gases. This area is moderately inhibited, and its soil is increasingly utilized in agricultural activities. High Fe, Cr, Mn, Pb, and V contents were recorded in the soil adjacent to the factory mainly concentrated on the prevailing wind direction. The studied sites bear heavy metalloids concentrations exceeding the permissible limit of WHO/EPA. These concentrations were found in topsoils and they decreased downward because of low mobility due of high soil alkalinity and lower pedogenesis. Moreover, the synchrotron-based XAFS technique was used to understand changes in oxidation states of Fe atom as well as in its structural parameters with depth. EXAFS analysis reveals association of Fe atoms mainly with oxygen (O), which indicates the anthropogenic Fe source. XANES data shows that Fe occurs in divalent (Fe²⁺) and trivalent (Fe³⁺) forms, which indicates that magnetite is dominating the topsoil. This Fe-phase is usually formed during oxygenated high thermal manufacturing processes. The topsoils SEM-EDS investigations confirmed the dominance of magnetite spheres, which coincides with the positive correlation between Fe and other elements as indicated from the statistical interpretation of the data.

The damage caused by mercury ions (Hg²⁺) to human beings motivates the development of highly efficient technologies for the removal of Hg²⁺ from water. Here, based on the coordination theory between functional groups and Hg²⁺, two covalent organic polymers (COPs) materials were successfully prepared by a more environmentally friendly Michael addition elimination reaction, and the thiourea structure, which has a particularly strong affinity for Hg²⁺, was successfully introduced into the material framework. The introduction of the special dithiourea structure created a rich environment of S and N atoms within the COPs structure, which exhibited high adsorption performance for Hg²⁺. Adsorption experiments showed that the dithiourea-functionalized COPs exhibited high adsorption capacities for Hg²⁺, with the maximum adsorption capacities of 840.9 and 880 mg g⁻¹ for the two materials, respectively. The adsorption performance remained relatively good after four adsorption-desorption cycles, and the adsorption selectivity for Hg²⁺ was intense. Mechanistic studies by X-ray photoelectron spectroscopy and density flooding theory calculations suggest that it is the S atoms within the structure that chelate with the Hg²⁺ and contribute to the adsorption capacity of the Hg²⁺. Therefore, this study provides a new strategy for the development of COP adsorbents for efficient removal of Hg²⁺ in aqueous solutions during remediation activities.