Water, Air, & Soil Pollution最新文献

PAHs pollution is a widespread pollution in river basins and wetland water bodies. A Northeast China chemical industry zone was studied, focusing on reclaimed water and sludge from sewage treatment plants. The pollution levels of 16 polycyclic aromatic hydrocarbons (PAHs) were monitored across three water periods. A model comparing pollution levels with sludge and recycled water aroma indices was established and validated. The model revealed interaction relationships among the 16 PAH pollutants. Analysis of bacterial communities identified the mechanism for combined phenanthrene and pyrene degradation, along with nine key enzymes involved. Population responses to 16 PAH pollution stress were explored, highlighting metabolic differences and functional relationships within eukaryotic and prokaryotic microbial communities. Molecular dynamics simulations identified a key enzyme, uncovering pi–pi T-shaped and pi–alkyl forces in the interaction between pyrene dioxygenase and pyrene.

The removal of pesticides from water sources is critically important for safe and clean drinking water. We investigated atrazine (ATZ) removal from various natural water sources using electrooxidation (EO) to cater to the need for safe drinking water. Under optimum operating conditions, 99% ATZ and ~ 70% TOC removal was achieved in 120 min of electrolysis time. Radical scavenging study and Electron Spin Paramagnetic Resonance (EPR) test showed that OH radicals and singlet oxygen were primarily responsible for the ATZ removal. ATZ removal was studied using synthetic water, filtered water, and river water, and the highest removal efficiencies observed were 98.30 ± 1.02%, 84.57 ± 1.18%, and 72.51 ± 1.34%, respectively. The phytotoxicity of EO-treated water was assessed using Vigna radiata seeds. The seed germination percentages observed at 0, 30, 90, and 120 min of EO treatment were 30, 50, 70, and 90%, respectively, compared to 100% obtained in the control (i.e., water without ATZ). Using solar energy as a power source instead of DC power reduced the total cost of the EO process by 12.78%. The EO process can effectively treat contaminated water, aiming to improve water quality and contributing to achieve sustainable development goals.

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The widespread discharge of nickel-contaminated wastewater into aquatic environments Presents a major threat to both human well-being and the environment. To address this issue, a sustainable and efficient adsorbent, Rumex abyssinicus-based activated carbon (RAAC), was developed for nickel removal. RAAC was synthesized by chemically activating Rumex abyssinicus with phosphoric acid and pyrolyzing it at 500°C. Characterization revealed that RAAC possesses a highly porous structure, making it highly effective for adsorption. Using factorial analysis methods, the adsorption process was optimized by investigating key parameters: pH, interaction duration, starting nickel levels, and the amount of adsorbent used. Nickel removal efficiency reached 99.2% under optimal conditions: a pH of 9, a 40-min interaction period, an initial nickel level of 40 mg/L, and an adsorbent amount of 0.2 g/100 mL. The Langmuir isotherm provided the best fit for the experimental data, suggesting monolayer adsorption with a maximum adsorption capacity of 101.33 mg/g. The Dubinin-Radushkevich (D-R) isotherm further confirmed the adsorption behavior, yielding a maximum capacity of 76.07 mg/g and an adsorption energy of 107.40 kJ/mol, indicating a chemisorption mechanism. Kinetic analysis demonstrated that the adsorption process adhered to the pseudo-second-order model, further supporting the dominance of the chemisorption mechanism. The production cost of RAAC was calculated to be $3.55/kg. This study demonstrates that RAAC is a highly efficient and sustainable material for nickel removal.

Microplastics (MPs) carry and spread environmental pollutants far and wide. The surface structure of MPs changes when MPs are exposed to light, and which influences the adhesion of MPs to pollutants. In this study, ultraviolet (UV) irradiation (1000 W mercury lamp, 80W/cm²) was utilized to simulate the aging of PVC MPs in natural environments. The adsorption and desorption behaviors of PVC MPs on tildipirosin were investigated. Furthermore, Escherichia coli was used for antibiotic stress experiments. The results revealed that aged PVC MPs exhibited a new oxygen-containing absorption peak at 1736 cm⁻¹, attributing to the stretching of a C = O. Notably, tildipirosin adsorption by the pristine PVC MPs conformed to the pseudo-first-order kinetic model (R² = 0.975), while the aged PVC MPs followed the pseudo-second-order kinetic model. The adsorption process followed the Langmuir thermodynamic equation. Furthermore, the desorption rates of the pristine, 6-day-aged, and 12-day-aged PVC MPs were determined to be 24.2%, 24.3%, and 30.7%, respectively. Thus, the data indicated that tildipirosin was more easily desorbed from the aged PVC MPs. pH studies showed that electrostatic forces significantly impacted tildipirosin adsorption. The antibiotics stress experiments demonstrated that Escherichia coli K12 could tolerate a higher concentration (40 mg/L) of tildipirosin undergoing the domestication with low concentration (12.8 mg/L tildipirosin) sequential stress. The findings of this study are expected to contribute to the understanding of the synergistic behavior of MPs and antibiotics in the environment and the ecological risks involved.

This study investigates the prevalence and risk assessment of per- and polyfluoroalkyl substances (PFAS) in the Delaware River, analyzing 23 water samples collected in 2019 and 2021. The concentration of prevalent chemicals (PFTeDA, PFTrDA, and PFDS) were significantly reduced from average values of 461.67 ng/L, 447.63 ng/L, and 137.10 ng/L between 2019 and 2021, as determined by the analysis of PFAS levels. The most prevalent chemicals in 2021 were PFOA and 6:2FTS, with average concentrations of 5.37 ng/L and 4.23 ng/L, respectively. Based on EPA guidelines, the study assessed environmental and human health hazards from the compounds in the source of drinking water samples using the risk quotient (RQ) and Hazard Index (HI). Following 2016 EPA guidelines, 75% of 2019 and 2021 source water samples had medium risk levels for combined PFOA and PFOS, while the rest were low risk. The RQ of the samples based on 2022 EPA guidelines showed high risk in 92.3% and 38.4% of 2019 collected samples for PFOA and PFOS, respectively. Based on their RQs, all the source water samples in 2021 showed high-risk levels of PFOA. Additionally, the 2023 EPA Hazard Index (HI) approach showed that PFBS, PFHxS, PFNA, and HFPO-DA do not exceed the threshold value. These results underscore the necessity of continuous monitoring and regulation to reduce the adverse effects of PFAS contamination on the Delaware River ecosystem and public health.

The Aogu Wetland Forest Park in Taiwan, a vital ecological hotspot within the East Asian-Australasian Flyway, faces significant threats from anthropogenic activities, agricultural runoff, and climate variability. This study integrated multiple analytical approaches, including Hierarchical Cluster Analysis (HCA), Canonical Correspondence Analysis (CCA), and Generalized Additive Mixed Models (GAMMs), to investigate the spatial and temporal variability of phytoplankton communities across six sites over an eight-year monitoring period (2015–2023). Phytoplankton diversity, assessed using Shannon–Wiener and Margalef indices, revealed distinct patterns driven by environmental gradients, with diversity indices ranging from 0.06 (DS2, May) to 2.21 (CS, July). HCA grouped sites into distinct clusters based on nutrient dynamics and salinity, indicating the influence of site-specific conditions. CCA identified ammonia (NH₄-N), nitrate (NO₃-N), temperature, and salinity as the most significant environmental drivers affecting genera-level distributions. GAMM analyses further quantified nonlinear interactions between phytoplankton abundance and key parameters, such as total dissolved solids (TDS), total phosphorus (TP), NH₄-N, and NO₃-N, providing detailed insights into how these factors vary across seasons and sites. The dominance of Cyanobacteria during colder months, with an average winter temperature of 27.8 °C, indicates the heightened risk of harmful algal blooms associated with nutrient enrichment. Seasonal dynamics showed that warmer summer months intensified the effects of nitrate and total phosphorus, driving site-specific phytoplankton proliferation. Adaptive wetland management strategies, including enhanced hydrological connectivity, nutrient runoff reduction, and targeted restoration, are essential to mitigate eutrophication and sustain ecological resilience. This approach provided practical insights for balancing conservation goals with ecosystem services in one of Taiwan’s key wetlands.

Nuclear operations generate significant amounts of radioactive liquids (RLs), posing a severe threat to the environment. Effective decontamination of RLs remains a challenge. This study introduces pumice as a novel, sustainable, and economical adsorbent for radionuclides removal. The characteristics of pure pumice were verified through X-ray diffraction, a scanning electron microscopy (SEM), a Fourier-transform infrared spectroscopy (FTIR), and X-ray fluorescence spectrometry. Batch experiments were conducted to evaluate the effectiveness of pumice in removing radionuclides from RLs. The gross alpha, beta, and gamma technique was used to concurrently radiologically characterize the RLs before and after decontamination. The operating conditions for the process included a 5-min stirring time, stirring speed at 100 rpm, mass of pumice 3 g/L, and a pH of 5. Initial gross beta and gamma activities were 29,766 and 4623 Bq/L, respectively, while the experiments were conducted at room temperature. The batch experiments demonstrated that pumice effectively removed 65.77% of gross beta and 61.73% of gross gamma radioactivity. The Freundlich isotherm model and the pseudo-second-order kinetic model accurately represented the adsorption process, suggesting a heterogeneity of surfaces and a chemical reaction between radionuclides and active pumice sites. System energy was endothermic and resulted in a decrease in energy dissipation and an increase in system order.

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Under the COVID-19-induced lockdown, there was a sharp decrease in pollution emissions, which led to previously unheard-of trends in India’s most dangerous pollutants. The study is considered for March-June 2020 to investigate the impact of lockdown on the concentrations of air pollutants, at the four stations in Andhra Pradesh, India. The study period was divided into Before Lockdown (BLD), During Lockdown (Phase-I (P-I), Phase-II (P-II), Phase-III (P-III), Phase-IV (P-IV)) and After Lockdown (ALD). The air pollutant concentrations over four stations were retrieved using in-situ measurements under the Central Pollution Control Board (CPCB), India network. The percentage contribution of PM_2.5 in PM₁₀ was recorded as 60–70% at Tirumala (TML) before lockdown (BLD), Phase-I, Phase-II, and low contribution at Visakhapatnam (VSK) of 10–40%. The maximum reduction in all pollutants recorded at Visakhapatnam (VSK) was up to 30–70%, and the highest reduction in PM₁₀, NO₂, and SO₂ was nearly 35–75% recorded at Tirumala (TML), which shows the effect due to the lack of human activities. In this study, the predominant changes occur in the first phase of the lockdown in all the studied air pollutant’s mean concentrations. Pollutant concentrations decreased across all sites during the lockdown, aligning with National Ambient Air Quality Standards (NAAQS) for the first time. The Spatial analysis showed varying degrees of improvement across four locations, experiencing a significant decrease in concentrations. Pearson’s correlations between pollutants and meteorological factors indicated that wind speed and direction changes influenced pollutant dispersion. Also, the XGBoost model demonstrated high predictive accuracy for PM_2.5 but tended to underpredict at higher concentrations, especially in complex urban environments. This study is for policymakers to develop precise mitigation strategies for air pollution to create a sustainable Environment.

The use of green infrastructure (GI) in urban environments has been widely investigated for its associated ecosystem services including air pollution mitigation. Plants are well-known for their ability of purifying air through photosynthesis and microbial activities occurring in the rhizosphere, however the simple filtration of particulate matter in air by plants is still not well understood. This study aimed to investigate the potential to adapt classic filtration theory for application in GI design. Two native Australian plants used as filter media were involved in laboratory experiments to remove aerosol particles ranging in size from 0.3 to > 10 µm. A comparison of aerosol removal efficiencies obtained from the laboratory experiments and predicted through classic filtration theory showed good correlation for the smaller (needle-like) leaf system. In contrast, the correlation obtained for a plant with larger elliptical leaves was not as good, showing a larger difference between the results. Such outcomes led to the conclusion that smaller and spatially homogeneous plant systems have more predictable aerosol filtration characteristics, which can be reasonably calculated using filtration theory. This finding provides practical insight into GI design, allowing quantitative predictions of local air pollution reductions using green barriers.

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