Environmental Science: Processes & Impacts最新文献

The impact of nanoplastics (NPs) and microplastics (MPs) on ecosystems and human health has recently emerged as a significant challenge within the United Nations Agenda 2030, drawing global attention. This paper provides a critical analysis of the influence of plastic particles on plants and soils, with the majority of data collected from recent studies, primarily over the past five years. The absorption and translocation mechanisms of NPs/MPs in plants are first described, followed by an explanation of their effects—especially particles like PE, PS, PVC, PLA, and PES, as well as those contaminated with heavy metals—on plant growth, physiology, germination, oxidative stress, and nutrient uptake. The study also links the characteristics of plastics (size, shape, concentration, type, degradability) to changes in the physical, chemical, and microbial properties of soils. Various mitigation strategies, including physical, chemical, and biological processes, are explored to understand how they address these changes. However, further research, including both laboratory and field investigations, is urgently needed to address knowledge gaps, particularly regarding the long-term effects of MPs, their underlying mechanisms, ecotoxicological impacts, and the complex interactions between MPs and soil properties. This research is crucial for advancing sustainability from various perspectives and should contribute significantly toward achieving sustainable development goals (SDGs).

Graphene has garnered significant attention due to its unique and remarkable properties. The widespread application of graphene materials in numerous fields inevitably leads to their release into the environment. This study examines the long-term impacts of graphene on anaerobic sequencing batch reactors. The low-concentration graphene (5 mg L⁻¹) exhibited a significant inhibitory effect on the removal of chemical oxygen demand, while the high-concentration group (100 mg L⁻¹) was less affected. The transmission electron microscopy and Raman spectroscopy results demonstrated that the anaerobic sludge could attack graphene materials, and cell viability tests showed that high concentrations of graphene were more conducive to microbial attachment. High-throughput sequencing revealed significant alterations in the microbial community structure under graphene pressure. Methanobacterium and Actinomyces gradually became the dominant genera in the high-concentration group. Network analysis showed that graphene increased the complexity and interaction of microbial communities. Additionally, high-throughput qPCR analysis demonstrated that graphene influenced the dynamics of antibiotic resistance genes, with most exhibiting increased abundance over time, especially in the low-concentration group. Consequently, when considering the application of graphene in wastewater treatment, it is crucial to evaluate potential risks, including its effects on system performance and the likelihood of antibiotic resistance gene enrichment.

Particulate air pollution is an environmental problem recognized as a global public health issue. Although the toxicological effects of environmental particle matter (PM) have been reported, the mechanism underlying the effect of PM on protein conformational changes, which are associated with the development of various diseases, has yet to be elucidated. In this study, we investigated the effect of urban PM on the secondary structure of proteins using bovine serum albumin (BSA). An urban aerosol (CRM28) was used as the original PM (PMO) and washed with acetone to investigate the effect of PM with two different chemical compositions. After washing with acetone, the remaining PM fraction contained decreased amounts of ions and carbon, while the metallic concentration was increased; thus, this PM fraction was labeled as PMM. After incubation of BSA with PM, the samples were subjected to Fourier-transform infrared (FT-IR) spectroscopy to investigate the changes in the absorption peak of the amide I band. BSA incubated with PMO and PMM showed an increase in the β-sheet ratio to the total secondary structure. Furthermore, the β-sheet content was more significantly increased when mixed with PMM (by 22.6%), indicating a more significant effect of the metallic fraction on the formation of β-sheets. In comparison, the lowest total amount of α-helix and β-sheets (with a decrease of 8.5%) was observed after incubation with PMO, associated with the protein partial unfolding in the presence of ions and carbonaceous PM constituents. The potential of a long-term effect of PM composition on protein structure would be of future interest in in vivo time-course studies.

Volatile organic compounds (VOCs) are released from many sources indoors, with ingress of outdoor air being an additional source of these species indoors. We report indoor VOC concentrations for 124 homes in Bradford in the UK, collected between March 2023 and April 2024. Whole air samples were collected over 72 hours in the main living area of the home. Total VOC (TVOC) concentrations in the homes were highly variable, ranging from 100 μg m⁻³ to >8000 μg m⁻³ (median concentration ∼1000 μg m⁻³). Acetaldehyde and 1,3-butadiene concentrations in >75% of homes were found to be in exceedance of the 1 in 1 000 000 lifetime cancer risk threshold. Higher concentrations of benzene, toluene, ethylbenzene and xylene (BTEX) as well as trimethylbenzenes were found in urban houses (summed xylene median 2.35 μg m⁻³) compared to rural homes (summed xylene median 1.22 μg m⁻³, p-value = 0.02), driven by ingress of elevated outdoor BTEX and trimethylbenzenes (outdoor urban BTEX median 1.69 μg m⁻³, outdoor rural BTEX median 0.78 μg m⁻³). Inferred air change rate (ACR) exhibited a degree of seasonality, with average ACR varying between median values of 1.2 h⁻¹ in the summer and 0.70 h⁻¹ in winter. Time-averaged emission rate data provided additional insight compared to measured concentrations, such as seasonal variability, with highest total VOC time-averaged emission rates occurring in summer months (median 51 953 μg h⁻¹), potentially a product of both increased occupancy times during school holidays as well as off-gassing of VOCs from surfaces. This comprehensive analysis underscores the critical role of seasonal, spatial, and contextual factors in shaping indoor VOC exposure, as well as potential health risks associated with consistently elevated concentrations of specific VOCs.

Phytoremediation is an effective technology for removing heavy metal cadmium (Cd) from soil without harming the soil; however, it is limited by its long remediation time and low efficiency. In this study, a plant growth regulator (PGR), triacontanol, was sprayed on the leaves of the hyperaccumulator Tagetes patula L. at different growth stages to enhance the accumulation of soil Cd, thereby ultimately enhancing the efficiency of phytoremediation. Results showed that leaves were the main site of Cd accumulation in T. patula, and foliar application of triacontanol increased the leaf biomass and Cd content, with maximum values of 14.69% and 15.44%, respectively. Furthermore, the Cd removal rate in the soil increased to 11.53%. The effect of a single application of triacontanol on Cd accumulation was better than that of two applications, and the bloom period was found to be the best application stage. The proportion of Cd in the cell walls increased, enhancing Cd fixation ability. The photosynthetic efficiency and antioxidant capacity of T. patula improved significantly. In the roots, metabolomic and transcriptomic analyses indicated that triacontanol promoted the metabolism of low-molecular-weight organic acids, leading to an increase in the available and exchangeable Cd in soil, with maximum values of 14.72% and 2.29%, respectively. The upregulation of Cd transport-related genes and pathways in the roots strengthened their ability to absorb Cd and resist Cd stress. These findings systematically elucidated the molecular mechanism of triacontanol-enhanced Cd accumulation in T. patula and provide technical support for its wide application.

Lead (Pb) has been used for centuries in currency, transportation, building materials, cookware, makeup, and medicine. Mining of Pb in the Roman era matched the ever-increasing demand for metallurgy, transportation, and industry, resulting in a marked deposition of human activity in the geologic record. Researchers use global snowpacks and ice cores to study the historic anthropogenic use of Pb and subsequent deposition into the environment. As the cryosphere resources erode with climate warming, there is an increased urgency to map the content and source of Pb distribution in the environment. In this systematic literature review, we examine studies of long-traveled background atmospheric lead signals in natural, undisturbed snowpacks and ice cores globally. After a systematic review of the literature, we have synthesized 165 published papers to contextualize current data availability and examine spatial and temporal coverage of existing long-range transported Pb records. Cumulatively, these papers contain 560 records for individual and transect sample sites. Of these site records, 147 are ice core analyses, 389 are from snowpits, and 24 span the snow to ice transition. The records are globally distributed, with a high concentration of records at the poles and fewer records at low latitude alpine sites. Long timescale records are available from the Greenland and Antarctic ice sheets (>100 000 years). Shorter timescale records are available for alpine glaciers (>15 000 years) and persistent snowpacks (generally <5 years). To illustrate the research potential of these records, we selected key global records to analyze and contextualize the Pb pollution record from the North Pacific, noting its unique record of China's industrial revolution and the subsequent explosion of industrial output from China over the last 45 years. Finally, we provide recommendations for future studies aimed at reducing current temporal and spatial gaps in the records. We suggest analyzing archived ice cores never before analyzed for Pb, focused proposals on regions with critical data gaps, continuous resampling of sites to include modern Pb emission sources, and use of analysis techniques which have low sample preparation requirements, high sensitivity, and capability for ultra-trace concentration Pb analysis.

Computational methods are crucial for assessing chemical biodegradability, given their significant impact on both environmental and human health. Organic compounds that are not biodegradable can persist in the environment, contributing to pollution. Our novel approach leverages graph attention networks (GATs) and incorporates node and edge attributes for biodegradability prediction. Quantitative Structure–Activity Relationship (QSAR) models using two-dimensional descriptors alongside weighted average and stacking approaches were employed to generate ensemble models. The GAT models demonstrated a stable function and generally higher specificity on the validation set compared to a graph convolutional network, although definitive superiority is challenging to establish owing to overlapping standard deviations. However, the sensitivities tended to decrease with potential performance overlap owing to the interval intersection. Ensemble learning enhanced several performance metrics compared with individual models and base models, with the combination of extreme Gradient Boosting and GAT achieving the highest precision and specificity. Combining GAT with random forest and Gradient Boosting may be preferable for accurately predicting biodegradable molecules, whereas the stacking approach may be suitable for prioritizing the correct classification of nonbiodegradable substances. Important descriptors, such as SpMax1_Bh(m) and SAscore, were identified in at least two QSAR models. Despite inherent complexities, the ease of implementation depends on factors such as data availability, and domain knowledge. Assessing the biodegradability of organic compounds is essential for reducing their environmental impact, assessing risks, ensuring regulatory compliance, promoting sustainable development, and supporting effective pollution remediation. It assists in making informed decisions about chemical use, waste management, and environmental protection.

Microplastic (MP) particles are ubiquitous in aquatic environments where they become exposed to UV-irradiation with subsequent alteration of surface properties. Such particles will interact with naturally occurring colloids being subject to processes like heteroaggregation that affect both MP surface properties and their removal rates from the water column. In this study, we investigated heteroaggregation and subsequent sedimentation of 1 μm polystyrene (PS, pristine and UV-weathered) with ferrihydrite (Fh), an iron (oxy)hydroxide commonly found in nature. Heteroaggregation of pristine PS with Fh was controlled by electrostatic attraction. At neutral pH values, strong heteroaggregation was observed which led to the sedimentation of almost all PS particles. UV-weathering of PS led to lower negative surface charge, decrease of particle size, and formation of degradation products. Changes in surface properties of PS resulted in a different aggregation behavior with Fh. With increasing weathering time, the isoelectric point (pH_IEP) of suspensions with PS and Fh shifted to lower pH values. Furthermore, we observed aggregation and subsequent sedimentation of weathered PS and Fh for a wider pH range (pH 3–7) compared to pristine PS (pH 6.5–7.5). We attribute this observation to increased surface reactivity of PS due to the formation of functional groups on the surface through UV-weathering. In addition, degradation products (e.g. oligomers) formed during weathering might have also interacted with PS and Fh and therefore further affected the surface properties of the particles. Overall, UV-weathering but also interactions of MP particles with environmental particles cause changes of MP surface properties, which influence its environmental behavior in water and might lead to a removal from the water column and accumulation in sediments.

The impact of organophosphate pesticide (OPP) exposure on osteoporosis in adult population remains unclear. Thus, it is necessary to explore the association between the exposure to a mixture of OPPs and the prevalence of osteoporosis as well as to identify the major contributor of OPPs in this association. Participants were selected from the 2005–2008 cycle of the NHANES cross-sectional study. OPP exposure was estimated using six different metabolites found in urine. Dual-energy X-ray absorptiometry (DXA) was used to measure bone mineral density (BMD). Survey-weighted generalized linear regression models (SWGLMs) were used to estimate the association between individual OPP exposure and osteoporosis/BMD. Weighted quantile sum (WQS) regression and quantile g-computation (Qgcomp) models were used to assess the mixture of OPPs and identify the key pollutants. SWGLMs indicated that higher concentrations of dimethyl dithiophosphate (DMDTP) and diethyl dithiophosphate (DEDTP) were associated with increased osteoporosis risk in the upper quartiles. WQS models revealed a significant combined effect of six OPP metabolites on osteoporosis (OR = 1.35, 95% CI: 1.06–1.73, P = 0.015), femoral neck BMD (β = −0.012, 95% CI: −0.020, −0.004, P = 0.003) and lumbar spine BMD (β = −0.015, 95% CI: −0.025, −0.006, P = 0.001), with DMDTP and DEDTP identified as key pollutants. Results from the Qgcomp models showed no substantial changes. This study indicated that exposure to both individual OPPs and their mixtures were associated with decreased BMD and increased osteoporosis risk, with DMDTP and DEDTP identified as major contributors to these associations. This underscores the need to prioritize control of these two pollutants to limit their exposure for osteoporosis prevention.

In recent decades, neonicotinoids (NEOs) have become widely adopted in agriculture for the control of crop pests and plant pathogens, leading to improved crop yields and enhanced agricultural productivity. However, the prolonged and widespread use of NEOs has raised significant concerns regarding their environmental persistence, food safety, and public health risks. These pesticides have been shown to contaminate various environmental compartments, including soil, surface water, and groundwater, posing potential hazards to ecosystems and human health. Microbes play a crucial role in mitigating the environmental impact of toxic pesticides, with microbial degradation emerging as a promising, cost-effective strategy for degrading pesticide residues. Several sulfoxaflor (SUL)-degrading microbes have been isolated and characterized, yet the identification of microbes, genes, and enzymes responsible for the degradation of NEOs remains an area requiring further investigation. Despite some progress, few reviews have comprehensively addressed the underlying mechanisms of NEOs degradation. This paper provides a detailed review of research on the environmental distribution, exposure risks, and ecotoxicological effects of NEOs, with a particular focus on the environmental fate of SUL. It aims to offer a novel perspective on the fate of NEOs in the environment, their potential toxicological effects, and the role of microbes in mitigating their impact.