Science of the Total Environment最新文献

Ultrafine particles (UFPs), an integral component of air pollution generated through dynamic processes, possess high surface reactivity and heterogeneous chemistry that drives toxicity. UFPs toxicity is associated with oxidative stress and inflammation at the olfactory-brain interface, which are also common in age-related diseases of the brain. However, how UFPs composition shapes time-resolved cellular injury and adaptation in aged individuals remains unclear. Cells of the olfactory mucosa (OM), which directly interface with inhaled air and provide access to the brain, offer a relevant model to assess these effects. This study investigates source-specific and time-dependent effects of UFPs on primary human OM cells, focusing on the interplay between particle composition, exposure duration, and age-related susceptibility to UFPs. OM cells from aged female donors were exposed invitro to well-characterized UFPs collected from a megacity (Nanjing, China) and a Nordic urban area (Kuopio, Finland). Transcriptional responses were profiled at 4, 12, 24, and 72 h, alongside assays for cytotoxicity, DNA damage, and cell-cycle dynamics. Interaction modeling identified 2614 genes with divergent temporal trajectories between sources. Nanjing metals and polycyclic aromatic hydrocarbons rich UFPs produced sustained oxidative stress, DNA damage, early G0/G1 checkpoint activation, and a senescence-linked transcriptional program (p53/p21 axis). While Kuopio mineral-/biomass- influenced UFPs elicited a milder viability loss, S/G2 enrichment, and a compensatory proliferative transcriptomic signature after 12 h exposure. Overall, UFP-induced toxicity in OM cells is both source- and time-dependent. UFPs chemical properties dictated the pace and nature of cellular response and adaptation at the olfactory interface in OM cells derived from aged individuals, underscoring the need for composition-aware air-pollution risk assessment in aging populations.

A deeper understanding of the transport processes and pathways of pollutants and plastic debris in aquatic environments, such as water bodies, riverine and coastal zones, is required to effectively understand, prevent, and mitigate marine pollution. In this study, we present an updated version of the high-performance, three-dimensional Canadian Microplastics Simulation (CaMPSim-3D) particle tracking model (PTM), focused on simulating microplastics transport in marine and riverine environments. CaMPSim-3D is an efficient tool that utilizes the principles of ray tracing to enhance the accuracy and performance of particle simulations. New features of the PTM include the implementation of free-slip boundary conditions, particle settling and resuspension mechanisms, and turbulent diffusion, which improve the solution of the diffusion equations. A novel method for computing gradients over triangular prism elements and a double ray casting approach to solve the diffusion equations are also proposed. Additionally, accurate particle settling velocity for circular and elliptical microplastic fibres has been incorporated into the model. Several test cases are presented to demonstrate the new features of the PTM. A sensitivity analysis is performed to investigate the effects of different boundary conditions, particle settling velocity, and turbulent diffusion on the transport and fate of microplastics at two sites: the Saguenay Fjord and the Ottawa River. A test case for model validation against field sampling is also presented for the Ottawa River. The results show that the PTM is efficient, and the use of turbulent diffusion and settling/resuspension mechanisms is necessary, particularly when simulating sinking particles with higher density than water. The findings of this study provide valuable insights into the transport processes of microplastics in aquatic environments and can be used to improve the accuracy of microplastics simulations as well as to identify microplastics accumulation areas.

Rouen, a densely populated city, is subject to anthropogenic pressure on its aquatic systems, resulting from both diffuse urban and industrial activities. In September 2019, a major fire at a chemical plant released 9500 tons of chemicals, generating a massive smoke plume. To assess its medium- and long-term impact on water bodies, sampling campaigns were carried out at three surface waters and two groundwater sites. Between 2021 and 2023, water and suspended particulate matter (SPM) were collected using passive samplers. Targeted analyses were performed to determine the concentrations and exported fluxes of selected regulated contaminants, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and dioxins/furans. In parallel, untargeted analyses were conducted using chromatography coupled with high-resolution mass spectrometry (GC-HRMS, LC-HRMS) and ultra-high-resolution Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS). Chromatogram reprocessing enabled the annotation of dozens of organic compounds, which were compared with an in-house database. The targeted analyses revealed a strong anthropogenic influence on surface and groundwater quality. The surface rivers located near the city center and the plant area were the most impacted, showing relatively elevated specific particulate PAH fluxes and the highest dioxin concentrations in SPM. But no direct causal link could be established between the targeted contaminants and the fire incident. In contrast, untargeted analyses identified non-regulated organic molecules potentially associated with the fire, in both dissolved and particulate phases, suggesting that the accident left a persistent chemical signature in the aquatic environment. SPM collected at sites closest to the plant exhibited the strongest presence of these potential fire markers.

Environmental microplastics (MPs) are ubiquitous contaminants with potential to harm organisms, including birds. Birds are exposed to MPs, although the mechanisms through which they ingest MPs are currently unclear. Examining the gut contents or feces of birds has provided insight into their ingestion of MPs, but previous research has put relatively little focus on passerines, which are the largest and most diverse order of birds. We collected fecal samples from five species of passerines which vary in their diets and foraging locations: Common Yellowthroat Geothlypis trichas, Gray Catbird Dumetella carolinensis, Northern Cardinal Cardinalis cardinalis, Wood Thrush Hylochichla mustelina, and White-throated Sparrow Zonotrichia albicollis. We quantified and characterized MPs in fecal samples, and used procedural and field blanks to account for MP contamination. We found MPs in samples from all five species. Ground foraging birds had more MPs in their feces by both count and density. While all species had mostly fiber-shaped MPs in their feces, insectivorous birds had more fragment-shaped MPs compared to birds with mixed diets. Transparent was the most common color of MP across all species. Our results suggest that MP exposure differs between species based on characteristics of their feeding behavior, and thus certain species of passerines may be more at risk than others of the deleterious effects of MPs on fitness. Moving forward, bird feces could be used to monitor MP presence in the environment, but it is important to consider these differences among species when designing monitoring efforts.

Wildfires significantly impact biodiversity, yet their effects on acoustic communities and soundscapes more generally are still not fully comprehended. This study employs passive acoustic monitoring (PAM) and ecoacoustics tools to assess the impact of human-caused wildfires on the anuran communities and the soundscape composition in the premontane strata of the Yungas Andean forests of Argentina. We deployed nine automated recording units across burned, semi-burned, and non-burned forest sites. We assessed anuran species richness by manual annotations from the recordings and analyzed the soundscape diversity and composition using Operational Sound Units and Hill-based soundscape diversity indices. Non-burned forest sites exhibited significantly higher anuran species richness compared to fire-affected sites. In addition, soundscape diversity was reduced in fire-affected sites, with non-burned forests retaining high-frequency biophony, unlike burned forests dominated by low-frequency sounds. Principal coordinate analysis revealed differences in soundscape composition among acoustic communities, with burned and semi-burned sites clustering separately from non-burned sites. Daily sound patterns showed dramatic changes in burned areas, indicating disrupted ecological acoustic niches. Our findings show that wildfires significantly alter both the anuran diversity and soundscapes composition, particularly affecting habitat-specialist species like treefrogs. Ecoacoustic tools effectively captured imminent post-fire soundscape changes, highlighting their utility for monitoring impacts on biodiversity. These results underscore the need for integrated wildfire prevention programmes aiming to conserve acoustic communities and soundscapes in threatened ecosystems. Long-term PAM is recommended to track post-fire biodiversity recovery and to evaluate conservation actions in the Yungas forests and other fire-prone landscapes.

The study performed a life-cycle assessment of biofuel pellet production from microwave (MW) torrefied camelina straw and switchgrass through various pathways. A cradle-to-gate analysis and identifies the environmental impact, such as global warming associated with feedstock production, preparation, pretreatment by torrefaction, and densification of MW camelina straw (CS) and switchgrass (SG) pellets, using recycled plastic (high-density polyethylene (HDPE)) as a binder, was compared based on the functional unit of 1 kg CS and SG pellets. The regional method Impact 2002+, which uses midpoint and endpoint approaches, was applied to translate inventory data into potential environmental impacts. The results showed that MW-torrefied/biocarbon/HDPE pellet production generated lower global warming potential (0.00327 kg CO₂ eq. for torrefied CS with biocarbon/HDPE pellet and 0.00224 kg CO₂ eq. for torrefied SG with biocarbon/HDPE), and other categories varied in environmental impacts. This suggests that blending torrefied biomass-MW absorber (biocarbon) with HDPE to produce CS and SG pellets resulted in reduced GHG emissions, yielding a promising outcome that would help alleviate the environmental burden of waste plastic disposal.