Environmental Science and Pollution Research最新文献

Ciprofloxacin (CIP) is an extensively used broad-spectrum, fluoroquinolone antibiotic used for treating diverse bacterial infections. Effluent treatment plants (ETPs) worldwide lack technologies to detect or remediate antibiotics. CIP reaches the aquatic phase primarily due to inappropriate disposal practices, lack of point-of-use sensing, and preloaded activated charcoal filter at ETPs. The co-existence of bacteria and CIP in such aqueous pools has promoted fluoroquinolone resistance in bacteria and should be minimized. The worldwide accepted standard detection methodologies for the detection of CIP are high-performance liquid chromatography and mass spectrometry, which are lab-based, require state-of-the-art equipment, and are expensive. Hence, it is difficult to integrate them for on-site monitoring. Further, the current remediation technologies like conventional sludge-treatment techniques fail to remove antibiotics such as CIP. Several point-of-use technologies for the detection of CIP are being investigated. These typically involve the development of electrochemical sensors where substrates, modifiers, biorecognition elements, and their chemistries are designed and optimized to enable robust, point-of-use detection of CIP. Similarly, remediation techniques like adsorption, membrane filtration, ion exchange, photocatalysis, ozonation, oxidation by Fenton's reagent, and bioremediation are explored, but their onsite use is limited. The use of these sensing and remediation technologies in tandem is possibly the only way the issues related to antimicrobial resistance may be effectively tackled. This article provides a focused critical review on the recent advances in the development of such technologies, laying out the prospects and perspectives of their synergistic use to curb the menace of AMR and preserve antibiotics.

Wastewater treatment plant (WWTP) is a sustainable technique for making wastewater reusable for non-potable purposes. However, in developing countries, most conventional WWTPs are not equipped to trap all pharmaceutical residues (PRs) and pharmaceutically active chemicals (PhACs). This study aims to perform non-target screening of these contaminants in wastewater and explore health and environmental hazards and the removal efficiency of a WWTP in Malaysia. At Indah Water WWTP, a total of 28 wastewater samples (i.e., 2 L each of 14 influent and 14 effluent) were collected every day for a week from February to April 2023. The supernatant of the centrifuged sample was analyzed with the LCMS-QTOF system. Chromatographic profiles were analyzed, and the compounds were annotated using the METLIN database. Categorical data were statistically analyzed with SPSS 29.0 using a chi-square test and continuous variables using paired t-test and multiple regression. PRs like micronutrient (9, 2.3%) and PhACs like lipid (83, 20.8%) were more frequent. Detection frequencies of PRs and PhACs were 72 (18%) and 328 (82%), respectively. Efficiency of WWTP was 36.4 to 100% for PRs removal (mean ± SD: 65.85 ± 56.43%) and 20 to 100% for PhACs removal (mean ± SD: 49.30 ± 55.94%). A total of 943 (mean ± SD: 67.36 ± 43.28) and 400 (mean ± SD: 28.57 ± 32.44) unique PRs and PhACs were recorded. A total of 40 (10%) PRs and PhACs had the potential to irritate eyes, skin, and respiratory tract, and 46 (11.5%) chemicals needed to be avoided from being discharged into the environment. Though WWTP was 98.0% compliant with environmental standards, its efficiency should still be increased to remove the full range of PRs and PhACs. The research has implications for SDGs 6 and 14.

Human-induced global warming, primarily attributed to the rise in atmospheric CO₂, poses a substantial risk to the survival of humanity. While most research focuses on predicting annual CO₂ emissions, which are crucial for setting long-term emission mitigation targets, the precise prediction of daily CO₂ emissions is equally vital for setting short-term targets. This study examines the performance of 14 models in predicting daily CO₂ emissions data from 1/1/2022 to 30/9/2023 across the top four polluting regions (China, India, the USA, and the EU27&UK). The 14 models used in the study include four statistical models (ARMA, ARIMA, SARMA, and SARIMA), three machine learning models (support vector machine (SVM), random forest (RF), and gradient boosting (GB)), and seven deep learning models (artificial neural network (ANN), recurrent neural network variations such as gated recurrent unit (GRU), long short-term memory (LSTM), bidirectional-LSTM (BILSTM), and three hybrid combinations of CNN-RNN). Performance evaluation employs four metrics (R², MAE, RMSE, and MAPE). The results show that the machine learning (ML) and deep learning (DL) models, with higher R² (0.714-0.932) and lower RMSE (0.480-0.247) values, respectively, outperformed the statistical model, which had R² (- 0.060-0.719) and RMSE (1.695-0.537) values, in predicting daily CO₂ emissions across all four regions. The performance of the ML and DL models was further enhanced by differencing, a technique that improves accuracy by ensuring stationarity and creating additional features and patterns from which the model can learn. Additionally, applying ensemble techniques such as bagging and voting improved the performance of the ML models by approximately 9.6%, whereas hybrid combinations of CNN-RNN enhanced the performance of the RNN models. In summary, the performance of both the ML and DL models was relatively similar. However, due to the high computational requirements associated with DL models, the recommended models for daily CO₂ emission prediction are ML models using the ensemble technique of voting and bagging. This model can assist in accurately forecasting daily emissions, aiding authorities in setting targets for CO₂ emission reduction.

Water pollution because of the presence of heavy metals remains a serious worry. The present work demonstrates the exclusion of cobalt ion (or Co(II)) from water using novel and cost-effective biosorbents. Initially, the biosorbent was chemically modified using orthophosphoric acid and then subjected to calcination to result acid modified date seed biochar (AMDB). Three biosorbents (AMDB400, AMDB500, and AMDB600) were synthesized concerning different activation temperatures (400, 500, and 600 °C). The maximum biosorption of Co(II) was achieved on AMDB600 (149.5 mg/g), followed by AMDB500 (138.33 mg/g), and ADMB400 (129.17 mg/g). For all three biosorbents, the Co(II) removal remained effective within 50-100 min; later it reached saturation. The kinetic analysis suggested strong Co(II) adsorption on AMDB surfaces. The Co(II)-AMDB biosorption data fits well with Temkin isotherm, indicating the heterogeneity on the biosorbent surface and no interaction between adsorbed Co(II)-Co(II) species. The thermodynamic analysis suggested the exothermic and spontaneous adsorption. The intraparticle diffusion of Co(II) within the biosorbent was surface diffusion controlled, as characterized by pore volume and surface diffusion model. The biosorbent reusability was 88.7% after five adsorption-desorption cycles. Thus, presently synthesized biosorbent could be novel and cost-effective for Co(II) and other heavy metal elimination from water bodies.

This research investigates the interactive effects of elevated ozone (eO₃) and carbon dioxide (eCO₂) on stomatal morphology and leaf anatomical characteristics in two wheat cultivars with varying O₃ sensitivities. Elevated O₃ increased stomatal density and conductance, causing oxidative stress and cellular damage, particularly in the O₃-sensitive cultivar PBW-550 (PW), compared to HUW-55 (HW). Conversely, eCO₂ reduced stomatal density and pore size, mitigating O₃-induced damage by limiting O₃ influx. Ultrastructural analysis showed that eO₃ increased plastoglobule density and damaged chloroplast structure, while eCO₂ preserved chloroplast integrity and enhanced photosynthetic efficiency. Additionally, eCO₂ increased leaf thickness and improved mesophyll conductance, counteracting the negative effects of O₃ on leaf anatomy. The CO₂-induced modifications in stomatal and leaf anatomy significantly impacted plant physiology by altering stomatal conductance and O₃ uptake. The protective effect of eCO₂ was more pronounced in the O₃-sensitive cultivar PW than in the O₃-tolerant HW. These findings provide insights into the stomatal and leaf anatomical responses of plants under future climate conditions, aiding in the developing strategies to improve crop resilience and productivity under O₃ stress.

As tailpipe emissions have decreased, there is a growing focus on the relative contribution of non-exhaust sources of vehicle emissions. Addressing these emissions is key to better evaluating and reducing vehicles' impact on air quality and public health. Tailoring solutions for different non-exhaust sources, including brake emissions, is essential for achieving sustainable mobility. Studying emissions from vehicles in real-world scenarios provides a better understanding of their environmental impact compared to laboratory testing alone. This study presents findings on the direct measurement of brake particles and the characterization of this source of particulate matter in real-world conditions using a mobile laboratory. In situ measurements of particle concentration and size distribution showed good agreement with previous laboratory studies, indicating the suitability of the approach to investigate break particle emissions during real-world operation. The study demonstrates that particle size distributions can vary based on the temperature of the brake disk, which is influenced by the initial braking speed, with significant variations observed between speeds of 60, 80, 100, and 120 km/h. Particles with sizes between 6 and 523 nm were released into the air from the brake system, although it is likely that larger particles were also emitted but not captured due to the upper detection limit of the Engine Exhaust Particle Sizer. During harsh braking events, such as decelerations of 4.2 m/s² from 120 km/h, a concentration of up 10⁶ (#/cm³) was measured for particles under 8 nm. Moreover, scanning electron microscope analysis revealed that nanoparticles are present in the form of agglomerates, whose shape can change depending on the formation process. Elements present in the particles comprised mainly iron, copper, and aluminium, indicating wear of the brake pad materials and disk components.

The submarine groundwater discharge (SGD) into the sea is known to alter various biotic and abiotic properties of coastal waters. However, its influence on the lower trophic levels, namely, meiofauna, is poorly understood. This study highlights the impact of SGD on the density, distribution, and diversity of intertidal meiofaunal communities along the subterranean estuaries (STEs) of the southwest coast of India (Arabian Sea). As an outcome of extensive field sampling between 2019 and 2022, we found that groundwater discharge has a direct influence on the local meiofaunal communities. Significant decline in meiofaunal density and diversity in the SGD impacted sites with 2 to 4 times lower densities than the unimpacted sites were documented. Lower groundwater salinity, lesser organic carbon content, hypoxic sediment conditions, and lower mean grain size in STEs can be the major driving factors determining the lower meiofaunal densities. δ¹³C and δ¹⁵N isotopic signatures indicated that major sources of organic carbon in STEs of the Kerala coast are from C3 plants.

Applying nano-delivery systems for phytohormones via foliar application has proven effective in reducing grain cadmium (Cd) levels in crops. However, the mechanisms underlying this reduction remain inadequately understood. This study integrated the determination of leaf photosynthetic parameters, Cd translocation analysis, and metabolomics to elucidate the effects of reduced glutathione (GSH) and melatonin (MT), delivered with or without chitosan-encapsulated mesoporous silica nanoparticles (MSN-CS), on grain Cd levels in rice. Our findings revealed that the foliar application of MT@MSN-CS significantly outperformed MT alone in reducing grain Cd levels and enhancing leaf photosynthesis under Cd stress. Conversely, GSH@MSN-CS showed comparable effects to GSH alone. Foliar-applied GSH@MSN-CS and MT@MSN-CS both decreased the Cd transport coefficients from panicle nodes to brown rice by 26.2-53.3%, with MT@MSN-CS demonstrating superior efficiency in reducing Cd concentrations across roots, stems, leaves, panicle nodes, and grains. Metabolomic analysis revealed substantial shifts in rice metabolite profiles following GSH@MSN-CS and MT@MSN-CS treatments. Foliar application of MT@MSN-CS or GSH@MSN-CS may rapidly and effectively activate the primary antioxidant defense system and alleviate membrane lipid peroxidation in rice grown on low-to-moderately Cd-contaminated soils by upregulating amino acid metabolism. The secondary defense mechanism, phenylpropanoid biosynthesis, was reprogrammed to reduce energy expenditure and decrease Cd translocation.

Mosses and lichens are often used to assess atmospheric deposition of ²¹⁰Pb. The most widely used method for determining this isotope is gamma spectrometric analysis. There is often a need to enhance the sensitivity of the method, which can be achieved by pre-concentrating ²¹⁰Pb. The simplest method in this case is direct dry ashing according to commonly accepted standardized procedures. However, the question of potential losses of ²¹⁰Pb during the combustion of mosses and lichens remains unclear. The main objective of this study is to investigate the effect of the dry ashing procedure on the accuracy of determining ²¹⁰Pb concentrations in the studied samples. The conducted experiment showed that ashing samples with low (< 8%) ash content, which includes all mosses and lichens, at a temperature of 450 °C leads to significant losses of ²¹⁰Pb (up to 40%). For samples with an ash content > 14% (litter), the losses of this isotope do not exceed 3-4%. For both groups, the value of ashing losses has a nearly linear dependence, inversely proportional to the ash content in the studied material. The obtained relationships allowed us to calculate the corrections necessary to account for ²¹⁰Pb losses during ashing of both low and high ash materials. The application of several statistical tests demonstrated good convergence and consistency of the results of ²¹⁰Pb determination obtained by direct measurement in unashed samples and those calculated through the measured activity of this isotope in ashes, corrected for ashing losses.

The use of rare earth elements has increased in recent years, leading to a rise in environmental concentrations. Despite the growth in number of studies regarding toxicity, knowledge gaps remain. For Daphnia magna, standardized test methods involve exposure periods of either 48 h or 21 days to assess toxicological effects. In this study, the exposure period was adjusted to 7 days to evaluate sublethal endpoints not measurable in 48-h tests. Additionally, this approach enabled us to obtain results within a shorter time frame than that required for 21-day tests. This study focused on the individual toxicity of lanthanum (La) and gadolinium (Gd) to Daphnia magna. We assessed mortality, feeding rate, somatic growth, and maturity under static conditions, modifying the media by adding MOPS buffer to maintain an initial pH of 6.8 and providing Raphidocelis subcapitata as a daily food source. Results showed that the solubility of La decreased considerably, with the highest recovery rate dropping from 133.33% at the start to 32.73% by the end of the 7-day exposure period. In contrast, Gd solubility remained stable, with a recovery rate of 86.88% at the start and 81.30% at the end of the test. Daily lethal concentrations (LC_x) were calculated, revealing LC₁₀ values on the first day, LC₂₀ on the second day, and LC₅₀ by the third day for La and the second day for Gd. By the test's end, the LC₁₀, LC₂₀, and LC₅₀ values were 30.40, 78.96, and 403.67 µg L^-1 for La, and 10.67, 33.73, and 241.28 µg L^-1 for Gd. For the sublethal endpoints, maturity was the most sensitive endpoint with the EC₂₀ and EC₁₀ corresponding to 0.79 and 0.26 µg L^-1 for La and 0.39 and 0.14 µg L^-1 for Gd. Gd had a higher toxicity in all endpoints assessed. While a thorough comparison to existing literature remains challenging due to variations in endpoints assessed, the methodology employed in this study yielded a range of informative results. This approach provides a useful range-finding test for Daphnia magna toxicity assessments, particularly for preliminary screening, and may complement standardized methodologies.