Environmental science. Advances最新文献

The risks to ecosystems that are posed by chemicals present in the environment need to be properly understood in order to ensure that they are both properly managed during their life cycle, and to understand the potential causes of serious ecological impacts. A mass mortality event which occurred off the North East coast of England in late 2021 affecting crabs and lobsters was an occasion when chemical risk assessment was used to help understand the possible causes. The environmental risk assessment of chemicals typically considers both the exposure to the chemical in question and the hazard posed by it to quantitatively evaluate the level of potential harm posed. There are established procedures for evaluating the relevance and reliability of both hazard and exposure data for chemicals, and their use within risk assessment provides traceability and clearly documents any limitations associated with the data which helps to ensure that they are not used inappropriately. The additional transparency surrounding the limitations and uncertainties associated with the data used can enhance the scientific credibility of assessments which are complex or politicized. This comment considers the quality of the evidence available for understanding whether pyridine may have been the cause of the mass crustacean mortality event which occurred off the North East coast of England in late 2021.

Swine manure mismanagement can lead to several environmental issues, such as eutrophication and gaseous emissions. This study examines swine manure solid separation using a coagulant (0.15 M FeCl₃) with unmodified and iron-modified corn stover biochar, and evaluates phosphorus (P) recovery efficiency from the separated solids using Mehlich-III, Olsen, and citrate-bicarbonate-dithionite (CBD) extractants. Adding a combination of 0.15 M FeCl₃ and iron-modified biochar to manure effectively separated 100% P from the solution into the solid fraction by forming a strong iron phosphate (P⁻) complex using inner-sphere and cation-bridging mechanisms. The spontaneity and feasibility of the process were assessed through a change in the Gibbs' free energy (ΔG⁰), which was determined to be −23.3 kJ mol⁻¹. We evaluated the nutrient stability of the manure solid fraction using conductometric and pH metric analyses, and Mehlich-III solution in the presence of a dispersive medium (0.15 M NaCl), and the manure was characterized using Raman and FTIR spectra. Furthermore, the release pattern of macronutrients was determined by the degree of dissociation under the influence of different extractants. It is worth mentioning that CBD successfully extracted P (7477 mg kg⁻¹) from cation-bridged P⁻ and iron-bound P⁻. This study presents an effective technique to separate P into solid fractions and offers a promising strategy for P recovery.

We investigated how temperature influences flame retardant levels in vehicle air and dust, and analyzed vehicle interior materials to identify major sources. Airborne concentrations of flame retardants varied dramatically, with some compounds increasing over 50 000-fold at elevated summer temperatures compared to winter temperatures. In contrast, dust levels were more stable but consistently high, reflecting substantial flame retardant content in interior materials. All sampled vehicle materials contained more than 1 μg g⁻¹ of three chlorinated organophosphate flame retardants. The combination of high material concentrations and temperature-driven emissions suggests that individuals who spend an extended time in vehicles may face elevated exposure to these chemicals, particularly during warmer conditions.

This study examines the environmental impact of blockchain technology operating under the Proof-of-Work (PoW) algorithm, with a focus on Bitcoin's (BTC) carbon footprint. Utilizing a comprehensive dataset comprising 2895 daily observations from 2014 to 2021, we analyze key mining-related variables—miner efficiency, miner revenues, total BTC mined, mining difficulty, and hash rate—through the application of a Bayesian Vector Autoregression (BVAR) model to evaluate their effects on CO₂ emissions over time. The primary objective is to identify the main determinants influencing BTC's carbon footprint within the current mining landscape. Our results indicate that BTC CO₂ emissions and mining difficulty are the most significant factors affecting carbon emissions. As mining difficulty increases—typically due to the entry of more miners and the deployment of more powerful hardware—profit margins decrease. High-cost, energy-intensive rigs may temporarily cease operations, leading to a reduction in output and a shift towards more efficient equipment. These findings reinforce and expand upon previous research by elucidating both the causal and time-varying dynamics of mining in relation to environmental outcomes. The results underscore the necessity for policies and industry practices that promote the adoption of more energy-efficient mining hardware and encourage the use of renewable energy sources in cryptocurrency mining. Supporting technological innovation and sustainable energy integration is essential for mitigating the environmental footprint associated with PoW-based blockchain systems such as BTC.

Shallow, eutrophic lakes often exhibit high and extremely variable phytoplankton biomass. This variability makes drinking water supply from shallow lakes particularly vulnerable to rapid change, as phytoplankton blooms can strongly impact treatment processes. Using 39 years of water quality data (typically bi-weekly), this study investigates the roles of climate variability and flow management in driving change in chlorophyll a (an indicator of phytoplankton biomass) in a shallow, hydrologically managed drinking water reservoir. Generalized additive modelling shows a significant increase in phytoplankton biomass (1992–1997), leading to a doubling of average chlorophyll a concentrations. Interestingly, we also see a shift towards smaller spring blooms and larger summer blooms. Our results show this variability in phytoplankton is largely related to climate variability, nutrients, and flow source. Specifically, the increase in phytoplankton biomass coincided with periods with greater precipitation and associated nutrient-rich inflows from an agriculturally dominated catchment, along with strong El Niño events that potentially contributed to a warm, stable water column during the growing season. During high flows from the local catchment, flows from the upstream supply reservoir are typically reduced to prevent downstream flooding. However, flows from the supply reservoir have a diluting impact due to its lower nutrient concentrations. Thus, where reservoir flow sources vary in chemistry, considering water quality in flow management could help to ameliorate bloom severity and reduce drinking water treatment costs. Importantly, understanding management and climatic drivers of reservoir water quality contributes to advance planning and mitigation of risks to water treatment.

Welding emits high levels of particulate matter (PM) and ultrafine particles (UFPs), which are associated with health risks including asthma, chronic obstructive pulmonary disease (COPD), and certain cancers. This study quantifies inhalation doses and health risks from different PM size fractions (PM₁₀, PM_2.5, and UFPs: 15–595 nm) generated by Shielded Metal Arc Welding (SMAW), Wire Arc Additive Manufacturing (WAAM), and Friction Stir Welding (FSW) under typical industrial conditions. Real-time PM and UFP concentrations were measured using a scanning-mobility-particle-sizer and low-cost PM sensors. Inhalation doses were estimated based on age, height, breathing frequency, inhalation rate, activity levels, and density variation (2 to 7 g cm⁻³), with age-specific respiratory deposition (16–20, 21–40, 41–60 years) quantified via the multiple-path-particle-dosimetry model for total, regional, and lobar levels. For PM₁₀, the highest deposition fraction (80–95%) occurred in the head region of individuals aged 16–20, while PM_2.5 showed the highest deposition fraction in the 41–60 age group, particularly in the head (35–90%) and pulmonary (19%) regions. UFPs (<100 nm) are predominantly deposited in the thoracic and pulmonary regions, and the magnitude of UFP deposition in these regions increases with higher welding currents and voltages. SMAW and WAAM processes exhibited the highest particle deposition, with deposition of both PM and UFPs being greatest in the oldest age group. Within the lungs, the lower lobes showed the greatest particle deposition (21%), dominated by UFPs across all age groups. The estimated excess lifetime cancer risk (1.28 × 10⁻⁴ to 6.88 × 10⁻⁴) exceeded WHO benchmark thresholds, while hazard quotients for PM_2.5 (20–88) and PM₁₀ (16–81) were significantly above recommended safety limits. These findings underscore the urgent need to regulate occupational exposure and include UFPs in air quality standards.

Arctic pollution has been a focal point in environmental research over the past five decades. Recently, the number of pollutants identified as relevant to the Arctic has significantly increased. Consequently, the expert group on Persistent Organic Pollutants (POPs) and Chemicals of Emerging Arctic Concern (CEACs) of the Arctic Monitoring and Assessment Programme (AMAP) has prepared a series of assessments of contaminants in the Arctic, including influences of climate change. This review addresses local sources of Arctic organic pollutants associated with infrastructure in the Arctic. Industrial, military, and public infrastructures, including domestic installations, sewage treatment, solid waste management, and airports, were identified as significant local pollution sources. Additionally, operational emissions (e.g., from shipping, transportation, heating, and power production) contribute to the overall local pollution profile. Based on currently available scientific information, elevated POP and CEAC levels are mostly found in close proximity to identified local pollution sources. To date, hazardous effects have only been confirmed for a few selected chemicals, such as polycyclic aromatic compounds (PAC) and certain pharmaceutical residues. However, studies are biased in the sense that they often focus on well-known contaminants, at a risk of overlooking CEAC and their effects. The review identifies several measures to reduce human impacts on local Arctic environments, including (i) using local indicator pollutants in ongoing national monitoring schemes, (ii) harmonizing emission reduction policies and licensing of industrial activities in the region to minimize exposure risks and environmental pollution, (iii) encouraging local municipalities, industries, and related stakeholders to coordinate their activities to minimize pollutant emissions.

The widespread presence of microplastics and nanoplastics (MNPs) in stormwater poses significant risks to both ecological and human health, necessitating the development of effective and sustainable mitigation strategies. Stormwater management engineered porous media systems (SWMEPMS) have emerged as promising solutions, leveraging filtration processes to capture and retain MNPs while supporting Sustainable Development Goals (SDGs 6, 11, and 14). Despite their potential, research on the fate of MNPs within SWMEPMS remains limited. Most importantly, no prior study has systematically and comprehensively reviewed how SWMEPMS remove MNPs from stormwater, particularly in relation to removal mechanisms, porous media and MNP characteristics, and water chemistry, despite their growing application and relevance. To bridge this gap, the standardized PRISMA methodology was employed to review the sources, transport, retention, and removal characteristics of MNPs in SWMEPMS. Key findings of the review highlight that MNPs in stormwater runoff are predominantly composed of polymers, including polyethylene, polypropylene, polystyrene, and tire wear particles (TWPs). SWMEPMS demonstrate up to 100% removal efficiency through mechanisms like sedimentation, straining, entrapment, entanglement, accumulation, agglomeration, electrostatic interactions, and surface complexation. Engineered porous media characteristics, such as surface properties, particle size distribution, and porosity, play crucial roles in enhancing removal efficiency, with porous media like limestone and biochar demonstrating greater performance than sand. The presence of functional groups, such as carbonyl, hydroxyl, carboxyl, and amino groups, on either the media or MNPs enhanced the removal efficiency of SWMEPMS. This review synthesizes existing knowledge, identifies gaps, and offers recommendations for future research to enhance this technology.

The land application of livestock manure can have significant effects on the emergence and proliferation of antibiotic resistance genes (ARGs) and antibiotic residues in the soil–plant ecosystem. While previous studies have documented the effects of manure application on ARGs in either soil or plant compartments, research addressing its impact on ARGs concurrently in both soil and plants remains relatively limited. This study aims to assess the occurrence of ARGs in and on lettuce cultivated in soil with beef cattle manure application. Results showed that seven ARGs (bla_TEM, erm(B), erm(F), tet(M), tet(O), tet(Q), and tet(X)) and one class 1 integron–integrase gene (intI1) were quantified in both soil and lettuce compartments following manure application. The relative abundance of manure-borne tet(M), tet(Q), and tet(X) was significantly elevated in surface soils (Kruskal–Wallis tests, p < 0.05). Notably, tet genes increased by 1–3 orders of magnitude within the lettuce endosphere and roots, revealing a potential transmission from soil to lettuce. In contrast, the relative abundance of bla_TEM, erm(B), and erm(F) increased only in the episphere and root but not within the endosphere of lettuce. Additionally, concentrations of tylosin in surface soil showed positive correlations with tet genes, suggesting their potential roles in facilitating the ARG proliferation in the soil–plant ecosystem. In summary, this study demonstrates that manure application promoted the transmission of manure-borne ARGs from soil to lettuce, highlighting a potential pathway for human exposure to antimicrobial resistance through the food chain. This finding underscores the need for the development of manure management practices to mitigate ARG spread in agriculture.

Improper waste management in municipal dumpsites raises health concerns due to toxic elements (TEs). This study evaluates the enrichment, sources, and public health risks of TE contamination in an urban dumpsite in a southeastern city of Bangladesh. Nine TEs were determined spectrophotometrically from 175 representative soil samples of 35 sites. Pollution indices, the Positive Matrix Factorization (PMF) model, and Monte-Carlo Simulation (MCS) were employed in assessing contamination levels, apportion sources, and associated public health risks. The results revealed significant topsoil contamination, with Cd contributing 91% to the overall ecological risk. Three distinct sources contributing to TE contamination were identified: industrial sources (F₁, 15.78%, dominated by Cd), geogenic origins (F₂, 40.93%, characterized by Fe, Co, Mn, and Ni), and mixed residential/commercial/traffic sources (F₃, 43.30%, with high loadings of Cu, Zn, Pb, and Cr). Health risk assessment (HRA) revealed that children faced 4.61 times higher non-carcinogenic risk (NCR) and 2.53 times higher carcinogenic risk (CR) compared to adults. NCRs were primarily driven by Fe and Mn, while Ni, Cd, and Cr were the main contributors to CRs, exceeding acceptable limits. Using the PMF-HRA method, F₂ was identified as a significant source of both NCR (79.27% in children and 88.69% in adults) and CR (66.18% in children and 61.63% in adults), with F₃ also posing significant risks, particularly for children. These results highlight the urgent need for comprehensive waste management reforms and targeted remediation strategies at the studied dumpsite to mitigate TE contamination, safeguard public health, and protect the surrounding environment, particularly for vulnerable populations and critical infrastructure in the region.