On Nucleation Pathways and Particle Size Distribution Evolutions in Stratospheric Aircraft Exhaust Plumes with H2SO4 Enhancement.

Stratospheric aerosol injection (SAI) is proposed as a means of reducing global warming and climate change impacts. Similar to aerosol enhancements produced by volcanic eruptions, introducing particles into the stratosphere would reflect sunlight and reduce the level of warming. However, uncertainties remain about the roles of nucleation mechanisms, ionized molecules, impurities (unevaporated residuals of injected precursors), and ambient conditions in the generation of SAI particles optimally sized to reflect sunlight. Here, we use a kinetic ion-mediated and homogeneous nucleation model to study the formation of H2SO4 particles in aircraft exhaust plumes with direct injection of H2SO4 vapor. We find that under the conditions that produce particles of desired sizes (diameter ∼200-300 nm), nucleation occurs in the nascent (t < 0.01 s), hot (T = 360-445 K), and dry (RH = 0.01-0.1%) plume and is predominantly unary. Nucleation on chemiions occurs first, followed by neutral new particle formation, which converts most of the injected H2SO4 vapor to particles. Coagulation in the aging and diluting plumes governs the subsequent evolution to a narrow (σg = 1.3) particle size distribution. Scavenging by exhaust soot is negligible, but scavenging by acid impurities or incomplete H2SO4 evaporation in the hot exhaust plume and enhanced background aerosols can matter. This research highlights the need to obtain laboratory and/or real-world experiment data to verify the model prediction.

Air Pollution Drives Macrophage Senescence through a Phagolysosome-15-Lipoxygenase Pathway.

Urban particulate matter (PM; uPM) poses significant health risks, particularly to the respiratory system. Fine particles, such as PM2.5, can penetrate deep into the lungs and exacerbate a range of health problems, including emphysema, asthma, and lung cancer. PM exposure is also linked to extrapulmonary disorders such as heart and neurodegenerative diseases. Moreover, prolonged exposure to elevated PM levels can reduce overall life expectancy. Senescence is a dysfunctional cell state typically associated with age but can also be precipitated by environmental stressors. This study aimed to determine whether uPM could drive senescence in macrophages, an essential cell type involved in particulate phagocytosis-mediated clearance. Although it is known that uPM exposure impairs immune function, this deficit is multifaceted and incompletely understood, partly because of the use of particulates such as diesel exhaust particles as a surrogate for true uPM. uPM was collected from several locations in the United States, including Baltimore, Houston, and Phoenix. Bone marrow-derived macrophages were stimulated with uPM or reference particulates (e.g., diesel exhaust particles) to assess senescence-related parameters. We report that uPM-exposed bone marrow-derived macrophages adopt a senescent phenotype characterized by increased IL-1α secretion, senescence-associated ß-galactosidase activity, and diminished proliferation. Exposure to allergens failed to elicit such a response, supporting a distinction between different types of environmental exposure. uPM-induced senescence was independent of key macrophage activation pathways, specifically inflammasome and scavenger receptors. However, inhibition of the phagolysosome pathway abrogated senescence markers, supporting this phenotype's attribution to uPM phagocytosis. These data suggest that uPM exposure leads to macrophage senescence, which may contribute to immunopathology.

Quantifying the impact of urban road traffic on air quality: activity pre-pandemic and during partial and full lockdowns.

The impact of partial and full COVID lockdowns in 2020 on vehicle miles traveled (VMT) in Kuwait was estimated using data extracted from the Directions API of Google Maps and a Python script running as a cronjob. This approach was validated by comparing the predictions based on the app to measuring traffic flows for 1 week across four road segments considered in this study. VMT during lockdown periods were compared to VMT for the same calendar weeks before the pandemic. NOx emissions were estimated based on VMT and were used to simulate the spatial patterns of NOx concentrations using an air quality model (AERMOD). Compared to pre-pandemic periods, VMT was reduced by up to 25.5% and 42.6% during the 2-week partial and full lockdown episodes, respectively. The largest reduction in the traffic flow rate occurred during the middle of these 2-week periods, when the traffic flow rate decreased by 35% and 49% during the partial and full lockdown periods, respectively. The AERMOD simulation results predicted a reduction in the average maximum concentration of emissions directly related to VMT across the region by up to 38%, with the maximum concentration shifting to less populous residential areas as a result of the lockdown.

Physiological impacts of atmospheric pollution: Effects of environmental air pollution on exercise.

In this review, we discuss some of the recent advances in our understanding of the physiology of the air pollution and exercise. The key areas covered include the effect of exercise intensity, the effects of pre-exposure to air pollution, acclimation to air pollution, and the utility of masks during exercise. Although higher intensity exercise leads to an increase in the inhaled dose of pollutants for a given distance traveled, the acute effects of (diesel exhaust) air pollution do not appear to be more pronounced. Second, exposure to air pollution outside of exercise bouts seems to have an effect on exercise response, although little research has examined this relationship. Third, humans appear to have an ability to acclimate to ground level ozone, but not other pollutants. And finally, masks may have beneficial effects on certain outcomes at low intensity exercise in pollution with significant levels of particles, but more study is required in realistic conditions.

Self-reported exposure to dust and diesel exhaust, respiratory symptoms, and use of respiratory protective equipment among Arctic miners.

Arctic miners face significant risks from diesel exhaust and dust exposure, potentially leading to adverse respiratory health. Employers must limit harmful exposures, using personal protective equipment (PPE) as a last line of defense. This study explored the association between reported respiratory exposure and symptoms, and PPE training and usage. Data from the MineHealth study (2012-2014) included a total of 453 Arctic open pit miners in Norway, Sweden, and Finland. Participants answered questions on exposure to dust and diesel exhaust, respiratory symptoms, and PPE use, in addition to age, gender, BMI, smoking, and self-rated health. Estimated exposure to dust was common, reported by 91%, 80%, and 82% and that of diesel exhaust by 84%, 43%, and 47% of workers in Sweden, Finland, and Norway, respectively. Reported dust exposure was significantly related to respiratory symptoms (OR 2.2, 95% CI 1.3-3.7), diesel exposure increased the occurrence of wheezing (OR 2.6, 95% CI 1.3-5.4). PPE use varied between the studied mines. Non-use was common and related to reduced visibility, wetness, skin irritation and fogging of the respiratory PPE. Future research should employ more precise exposure assessment, respiratory function as well as explore the reasons behind the non-compliance of PPE use.

Sustained Reductions of Bay Area CO2 Emissions 2018-2022.

Cities represent a significant and growing portion of global carbon dioxide (CO2) emissions. Quantifying urban emissions and trends over time is needed to evaluate the efficacy of policy targeting emission reductions as well as to understand more fundamental questions about the urban biosphere. A number of approaches have been proposed to measure, report, and verify (MRV) changes in urban CO2 emissions. Here we show that a modest capital cost, spatially dense network of sensors, the Berkeley Environmental Air Quality and CO2 Network (BEACO2N), in combination with Bayesian inversions, result in a synthesis of measured CO2 concentrations and meteorology to yield an improved estimate of CO2 emissions and provide a cost-effective and accurate assessment of CO2 emissions trends over time. We describe nearly 5 years of continuous CO2 observations (2018-2022) in a midsized urban region (the San Francisco Bay Area). These observed concentrations constrain a Bayesian inversion that indicates the interannual trend in urban CO2 emissions in the region has been a modest decrease at a rate of 1.8 ± 0.3%/year. We interpret this decrease as primarily due to passenger vehicle electrification, reducing on-road emissions at a rate of 2.6 ± 0.7%/year.

Differential impact of diesel exhaust particles on glutamatergic and dopaminergic neurons in Caenorhabditis elegans: A neurodegenerative perspective.

The growing body of evidence links exposure to particulate matter pollutants with an increased risk of neurodegenerative diseases. In the present study, we investigated whether diesel exhaust particles can induce neurobehavioral alterations associated with neurodegenerative effects on glutamatergic and dopaminergic neurons in Caenorhabditis elegans (C. elegans). Exposure to DEP at concentrations of 0.167 µg/cm2 and 1.67 µg/cm2 resulted in significant developmental delays and altered locomotion behaviour. These effects were accompanied by discernible alterations in the expressions of antioxidant genes sod-3 and gst-4 observed in transgenic strains. Behaviour analysis demonstrated a significant reduction in average speed (p < 0.001), altered paths, and decreased swimming activities (p < 0.01), particularly at mid and high doses. Subsequent assessment of neurodegeneration markers in glutamatergic (DA1240) and dopaminergic (BZ555) transgenic worms revealed notable glutamatergic neuron degeneration at 0.167 µg/cm2 (∼30 % moderate, ∼20 % advanced) and 1.67 µg/cm2 (∼28 % moderate, ∼24 % advanced, p < 0.0001), while dopaminergic neurons exhibited structural deformities (∼16 %) without significant degeneration in terms of blebs and breaks. Furthermore, in silico docking simulations suggest the presence of an antagonistic competitive inhibition induced by DEP in the evaluated neuro-targets, stronger for the glutamatergic transporter than for the dopaminergic receptor from the comparative binding affinity point of view. The results underscore DEP's distinctive neurodegenerative effects and suggest a link between locomotion defects and glutamatergic neurodegeneration in C. elegans, providing insights into environmental health risks assessment.

Assessment of genotoxicity biomarkers in gasoline station attendants due to occupational exposure.

Gasoline station attendants are exposed to numerous chemicals that might have genotoxic and carcinogenic potential, such as benzene in fuel vapor and particulate matter and polycyclic aromatic hydrocarbons in vehicle exhaust emission. According to IARC, benzene and diesel particulates are Group 1 human carcinogens, and gasoline has been classified as Group 2A "possibly carcinogenic to humans." At gas stations, self-service is not implemented in Turkey; fuel-filling service is provided entirely by employees, and therefore they are exposed to those chemicals in the workplace during all working hours. Genetic monitoring of workers with occupational exposure to possible genotoxic agents allows early detection of cancer. We aimed to investigate the genotoxic damage due to exposures in gasoline station attendants in Turkey. Genotoxicity was evaluated by the Comet, chromosomal aberration, and cytokinesis-block micronucleus assays in peripheral blood lymphocytes. Gasoline station attendants (n = 53) had higher tail length, tail intensity, and tail moment values than controls (n = 61). In gasoline station attendants (n = 46), the frequencies of chromatid gaps, chromosome gaps, and total aberrations were higher compared with controls (n = 59). Increased frequencies of micronuclei and nucleoplasmic bridges were determined in gasoline station attendants (n = 47) compared with controls (n = 40). Factors such as age, duration of working, and smoking did not have any significant impact on genotoxic endpoints. Only exposure increased genotoxic damage in gasoline station attendants independently from demographic and clinical characteristics. Occupational exposure-related genotoxicity risk may increase in gasoline station attendants who are chronically exposed to gasoline and various chemicals in vehicle exhaust emissions.

Airborne environmentally persistent free radicals (EPFRs) in PM2.5 from combustion sources: Abundance, cytotoxicity and potential exposure risks.

As an emerging atmospheric pollutant, airborne environmentally persistent free radicals (EPFRs) are formed during many combustion processes and pose various adverse health effects. In health-oriented air pollution control, it is vital to evaluate the health effects of atmospheric fine particulate matter (PM2.5) from different emission sources. In this study, various types of combustion-derived PM2.5 were collected on filters in a partial-flow dilution tunnel sampling system from three typical emission sources: coal combustion, biomass burning, and automobile exhaust. Substantial concentrations of EPFRs were determined in PM2.5 samples and associated with significant potential exposure risks. Results from in vitro cytotoxicity and oxidative potential assays suggest that EPFRs may cause substantial generation of reactive oxygen species (ROS) upon inhalation exposure to PM2.5 from anthropogenic combustion sources, especially from automobile exhaust. This study provides important evidence for the source- and concentration-dependent health effects of EPFRs in PM2.5 and motivates further assessments to advance public health-oriented PM2.5 emission control.

VOC source apportionment, reactivity, secondary transformations, and their prioritization using fuzzy-AHP method in a coal-mining city in India.

This study assessed the air quality status in different functional zones of Dhanbad-a coal-mining and industrial hub, based on the measurement of aromatic and halogenated volatile organic compounds (VOCs) using gas chromatography. The study encompasses source apportionment of VOCs and their chemical reactivity in terms of OH radical loss rate (LOH), ozone-forming potential (OFP), and their secondary organic aerosol forming potential (SOAp). Furthermore, prioritization of VOCs based on a fuzzy-analytical hierarchical process (F-AHP) has also been done. The results found xylene species to have the highest concentration in all three seasons across traffic-intersection and industrial zones and toluene at the institutional zone. The study identified four sources using positive matrix factorization (PMF) model, viz., mixed traffic exhaust (35%), coal combustion sources (30%), industrial (26%), and solvent usage (9%). LOH and SOAp were ~ 16 times more at the industrial and traffic-intersection zone than the institutional zone. The aromatic species contributed 97% to the OFP, and many species exhibited less contribution to the mixing ratio of VOCs but displayed a high contribution to LOH, OFP, and SOAp, suggesting the need to prefer reactivity-based strategies in addition to concentration-based strategies in the future for their regulation. The F-AHP-based priority component analysis identified 16 species out of 29 in the priority watch list (nine in tier-1, four in tier-2, and three in tier-3). The paucity of data and lack of ambient air quality standards on VOCs (except benzene) make it difficult to determine which aspect should be dealt with first and which species require more attention. Therefore, the F-AHP method used in this study could help identify the influencing parameters to be considered while devising efficient VOC management policies.

Scenario analysis of energy consumption and related emissions in the transportation industry-a case study of Shaanxi Province.

In the context of pursuing carbon neutrality and balancing the use of fossil fuels with renewable energy, the transportation industry faces the challenge of accurately predicting energy demand, related emissions, and assessing the effectiveness of energy technologies and policies. This is crucial for formulating energy management plans and reducing carbon dioxide (CO2) and atmospheric pollutant emissions. Currently, research on energy consumption and emission forecasting primarily relies on energy consumption quantities and emission factors, which lack precision. This study employs the low emissions analysis platform (LEAP) model, utilizing a "bottom-up" modeling approach combined with scenario analysis to predict and analyze the energy demand and related emissions in the transportation industry. Compared to previous studies, the methodological framework proposed in this research offers higher precision and can explore energy-saving and emission-reduction pathways for different modes of transport, providing a valuable energy forecasting tool for transport policy formulation in other regions. The forecast results indicate that under the business-as-usual (BAU) scenario, by 2049, the energy consumption and related emissions in Shaanxi Province's transportation industry are expected to increase by 1.15 to 1.85 times compared to the baseline year. In the comprehensive (CP) scenario, the industry is projected to reach a carbon peak around 2033. The study also finds that energy consumption and emissions predominantly originate from private passenger vehicles, highway freight, and civil aviation passenger, which have the greatest potential for emission reduction under the transport structure optimized (TSO) scenario. Therefore, policymakers should consider regional development characteristics, combine different transportation modes, and specifically analyze the emission reduction potential of the transportation industry in various regions, formulating corresponding reduction policies accordingly.

Impacts of ethanol blended fuels and cold temperature on VOC emissions from gasoline vehicles in China.

The Chinese central government has initiated pilot projects to promote the adoption of gasoline containing 10%v ethanol (E10). Vehicle emissions using ethanol blended fuels require investigation to estimate the environmental impacts of the initiative. Five fuel formulations were created using two blending methods (splash blending and match blending) to evaluate the impacts of formulations on speciated volatile organic compounds (VOCs) from exhaust emissions. Seven in-use vehicles covering China 4 to China 6 emission standards were recruited. Vehicle tests were conducted using the Worldwide Harmonized Test Cycle (WLTC) in a temperature-controlled chamber at 23 °C and -7 °C. Splash blended E10 fuels led to significant reductions in VOC emissions by 12%-75%. E10 fuels had a better performance of reducing VOC emissions in older model vehicles than in newer model vehicles. These results suggested that E10 fuel could be an option to mitigate the VOC emissions. Although replacing methyl tert-butyl ether (MTBE) with ethanol in regular gasoline had no significant effects on VOC emissions, the replacement led to lower aromatic emissions by 40%-60%. Alkanes and aromatics dominated approximately 90% of VOC emissions for all vehicle-fuel combinations. Cold temperature increased VOC emissions significantly, by 3-26 folds for all vehicle/fuel combinations at -7 °C. Aromatic emissions were increased by cold temperature, from 2 to 26 mg/km at 23 °C to 33-238 mg/km at -7 °C. OVOC emissions were not significantly affected by E10 fuel or cold temperature. The ozone formation potential (OFP) and secondary organic aerosol formation potential (SOAFP) of splash blended E10 fuels decreased by up to 76% and 81%, respectively, compared with those of E0 fuels. The results are useful to update VOC emission profiles of Chinese vehicles using ethanol blended gasoline and under low-temperature conditions.

Quantifying the contributions of road and air traffic to ambient ultrafine particles in two urban communities.

Traffic-related activities are widely acknowledged as a primary source of urban ambient ultrafine particles (UFPs). However, a notable gap exists in quantifying the contributions of road and air traffic to size-resolved and total UFPs in urban areas. This study aims to delineate and quantify the traffic's contributions to size-resolved and total UFPs in two urban communities. To achieve this, stationary sampling was conducted at near-road and near-airport communities in Seattle, Washington State, to monitor UFP number concentrations during 2018-2020. Comprehensive correlation analyses among all variables were performed. Furthermore, a fully adjusted generalized additive model, incorporating meteorological factors, was developed to quantify the contributions of road and air traffic to size-resolved and total UFPs. The study found that vehicle emissions accounted for 29% of total UFPs at the near-road site and 13% at the near-airport site. Aircraft emissions contributed 14% of total UFPs at the near-airport site. Notably, aircraft predominantly emitted UFP sizes below 20 nm, while vehicles mainly emitted UFP sizes below 50 nm. These findings reveal the variability in road and air traffic contributions to UFPs in distinct areas. Our study emphasizes the pivotal role of traffic layout in shaping urban UFP exposure.

Characteristics of typical intermediate and semi volatile organic compounds in Shanghai during China International Import Expo event.

To ensure good air quality during the China International Import Expo (CIIE) event, stringent emission-reduction measures were implemented in Shanghai. To assess the efficacy of these measures, this study measured typical categories of intermediate/semi volatile organic compounds (I/SVOCs), including alkanes (C10-C26 n-alkanes and pristane), EPA-priority polycyclic aromatic hydrocarbons (PAHs), alkylnaphthalenes, benzothiazole (BTH) and chlorobenzenes (CBs), at an urban site of Shanghai before and during two CIIE events (2019 and 2020; non-CIIE versus CIIE). The average concentrations of alkanes and PAHs during both 2019 and 2020 CIIE events decreased by approximately 41% and 17%, respectively, compared to non-CIIE periods. However, the decline in BTH and CBs was only observed during CIIE-2019. Secondary organic aerosol (SOA) formation from alkanes, PAHs and BTH was evaluated under atmospheric conditions, revealing considerable SOA contributions from dimethylnaphthalenes and BTH. Positive matrix factorization (PMF) analysis further revealed that life-related sources, such as cooking and residential emissions, make a noticeable contribution (21.6%) in addition to the commonly concerned gasoline-vehicle sources (31.5%), diesel-related emissions (20.8%), industrial emissions (18.6%) and ship emissions (7.5%). These findings provide valuable insights into the efficacy of the implemented measures in reducing atmospheric I/SVOCs levels. Moreover, our results highlight the significance of exploring additional individual species of I/SVOCs and life-related sources for further research and policy development.

Biological effects of diesel exhaust inhalation. III cardiovascular function.

OBJECTIVE: Inhalation of diesel exhaust (DE) has been shown to be an occupational hazard in the transportation, mining, and gas and oil industries. DE also contributes to air pollution, and therefore, is a health hazard to the general public. Because of its effects on human health, changes have been made to diesel engines to reduce both the amounts of particulate matter and volatile fumes they generate. The goal of the current study was to examine the effects of inhalation of diesel exhaust. MATERIALS AND METHODS: The study presented here specifically examines the effects of exposure to 0.2 and 1.0 mg/m3 DE or filtered air (6h/d for 4 d) on measures of peripheral and cardio-vascular function, and biomarkers of heart and kidney dysfunction in male rats. A Tier 2 engine used in oil and gas fracking operations was used to generate the diesel exhaust. RESULTS: Exposure to 0.2 mg/m3 DE resulted in an increase in blood pressure 1d following the last exposure, and increases in dobutamine-induced cardiac output and stroke volume 1 and 27d after exposure. Changes in peripheral vascular responses to norepinephrine and acetylcholine were minimal as were changes in transcript expression in the heart and kidney. Exposure to 1.0 mg/m3 DE did not result in major changes in blood pressure, measures of cardiac function, peripheral vascular function or transcript expression. DISCUSSION AND CONCLUSIONS: Based on the results of this study, we suggest that exposure to DE generated by a Tier 2 compliant diesel engine generates acute effects on biomarkers indicative of cardiovascular dysfunction. Recovery occurs quickly with most measures of vascular/cardiovascular function returning to baseline levels by 7d following exposure.

Evaluation of neural reflex activation as a potential mode of action for respiratory and cardiovascular effects of fine particulate matter.

OBJECTIVES: Mortality from respiratory and cardiovascular health conditions contributes largely to the total mortality that has been associated with exposure to PM2.5 in epidemiology studies. A mode of action (MoA) for these underlying morbidities has not been established, but it has been proposed that some effects of PM2.5 occur through activation of neural reflexes. MATERIALS AND METHODS: We critically reviewed the experimental studies of PM2.5 (including ambient PM2.5, diesel exhaust particles, concentrated ambient particles, diesel exhaust, and cigarette smoke) and neural reflex activation, and applied the principles of the International Programme on Chemical Safety (IPCS) MoA/human relevance framework to assess whether they support a biologically plausible and human-relevant MoA by which PM2.5 could contribute to cardiovascular and respiratory causes of death. We also considered whether the evidence from these studies supports a non-threshold MoA that operates at low, human-relevant PM2.5 exposure concentrations. RESULTS AND DISCUSSION: We found that the proposed MoA of neural reflex activation is biologically plausible for PM2.5-induced respiratory effects at high exposure levels used in experimental studies, but further studies are needed to fill important data gaps regarding the relevance of this MoA to humans at lower PM2.5 exposure levels. A role for the proposed MoA in PM2.5-induced cardiovascular effects is plausible for some effects but not others. CONCLUSIONS: Further studies are needed to determine whether neural reflex activation is the MoA by which PM2.5 could cause either respiratory or cardiovascular morbidities in humans, particularly at the ambient concentrations associated with total mortality in epidemiology studies.

Lichen biomonitoring to assess spatial variability, potential sources and human health risks of polycyclic aromatic hydrocarbons (PAHs) and airborne metal concentrations in Manchester (UK).

Airborne metals and organic pollutants are linked to severe human health impacts, i.e. affecting the nervous system and being associated with cancer. Airborne metals and polycyclic aromatic hydrocarbons (PAHs) in urban environments are derived from diverse sources, including combustion and industrial and vehicular emissions, posing a threat to air quality and subsequently human health. A lichen biomonitoring approach was used to assess spatial variability of airborne metals and PAHs, identify potential pollution sources and assess human health risks across the City of Manchester (UK). Metal concentrations recorded in lichen samples were highest within the city centre area and along the major road network, and lichen PAH profiles were dominated by 4-ring PAHs (189.82 ng g-1 in Xanthoria parietina), with 5- and 6-ring PAHs also contributing to the overall PAH profile. Cluster analysis and pollution index factor (PIF) calculations for lichen-derived metal concentrations suggested deteriorated air quality being primarily linked to vehicular emissions. Comparably, PAH diagnostic ratios identified vehicular sources as a primary cause of PAH pollution across Manchester. However, local more complex sources (e.g. industrial emissions) were further identified. Human health risk assessment found a "moderate" risk for adults and children by airborne potential harmful element (PHEs) concentrations, whereas PAH exposure in Manchester is potentially linked to 1455 (ILCR = 1.45 × 10-3) cancer cases (in 1,000,000). Findings of this study indicate that an easy-to-use lichen biomonitoring approach can aid to identify hotspots of impaired air quality and potential human health impacts by airborne metals and PAHs across an urban environment, particularly at locations that are not continuously covered by (non-)automated air quality measurement programmes.

Are electric vehicles really the optimal option for the transportation sector in China to approach pollution reduction and carbon neutrality goals?

Profound worldwide fleet electrification is thought to be the primary route for achieving the target of carbon neutrality. However, when and how electrification can help mitigate environmental impacts and carbon emissions in the transport sector remains unclear. Herein, the overall life-cycle environmental impacts and carbon saving range of two typical A-class vehicles in China, including electric vehicle (EV) and internal combustion engine vehicle (ICEV), were quantified by the life cycle assessment model for endpoint damage with localization parameters. The results showed that the EV outperformed the ICEV for the total environment impact after a travel distance of 39,153 km and for carbon emissions after 32,292 km. The ICEV was more carbon-friendly only when the driving distance was less than 3229 km/a. Considering a full lifespan travel distance of 150,000 km, the whole life-cycle average environmental impacts of EV and ICEV were calculated as 8.6 and 17.5 mPt/km, respectively, but the EV had 2.3 times higher impacts than the ICEV in the production phase. In addition, the EV unit carbon emission was 140 g/km, 46.8% lower than that of the ICEV. Finally, three potential reduction scenarios were considered: cleaner power mix, energy efficiency improvement and composite scenario. These scenarios contributed 19.1%, 13.0% and 32.1% reductions, respectively. However, achieving carbon peak and neutrality goals in China remains a great challenge unless fossil fuels are replaced by renewable energy. The research can provide scientific reference for the method and practice of emission reduction link identification, eco-driving choice and emission reduction path formulation.

Establishment of a system to analyze effects of airborne ultra-fine particulate matter from brake wear on plants under realistic exposure conditions.

Research on airborne ultrafine particles (UFP) is driven by an increasing awareness of their potential effects on human health and on ecosystems. Brake wear is an important UFP source releasing largely metallic and potentially hazardous emissions. UFP uptake into plant tissues could mediate entry into food webs. Still, the effects of these particles on plants have barely been studied, especially in a realistic setting with aerial exposure. In this study, we established a system designed to mimic airborne exposure to ultrafine brake dust particles and performed experiments with the model species Arabidopsis thaliana. Using advanced analytical methods, we characterized the conditions in our exposure experiments. A comparison with data we obtained on UFP release at different outdoor stations showed that our controlled exposures are within the same order of magnitude regarding UFP deposition on plants at a traffic-heavy site. In order to assess the physiological implications of exposure to brake derived-particles we generated transcriptomic data with RNA sequencing. The UFP treatment led to diverse changes in gene expression, including the deregulation of genes involved in Fe and Cu homeostasis. This suggests a major contribution of metallic UFPs to the elicitation of physiological responses by brake wear derived emissions.

Impacts of ship emissions and sea-land breeze on urban air quality using chemical characterization, source contribution and dispersion model simulation of PM2.5 at Asian seaport.

Fine particulate matter (PM2.5) emitted from marine transportation, bulk materials handling at the docks, and dust dispersion has garnered increased attention, particularly in the interface between port and urban areas. This study explored the inter-transport of PM2.5 between Kaohsiung Harbor and neighboring Metro Kaohsiung. Chemical analyses of PM2.5 samples from four sites include water-soluble ions, metallic elements, carbons, anhydrosugars, and organic acids to establish PM2.5's chemical fingerprints. The CALPUFF air dispersion model is employed to simulate the spatiotemporal distribution of PM2.5 in Kaohsiung Harbor and adjacent urban areas. A clear seasonal and diurnal variation of PM2.5 concentrations and chemical composition was observed in both harbor and urban areas. The high correlation of nighttime PM2.5 levels between the port and urban areas suggests inter-transport phenomena. Sea salt spray, ship emissions, secondary aerosols, and heavy fuel-oil boilers exhibit higher levels in the port area than in the urban area. In Metro Kaohsiung, mobile sources, fugitive dust, and waste incinerators emerge as major PM2.5 contributors. Furthermore, sea breeze significantly influences PM2.5 dispersion from Kaohsiung Harbor to Metro Kaohsiung, particularly in the afternoon. The average contribution of PM2.5 from ships' main engines in Kaohsiung Harbor ranges from 2.9% to 5.3%, while auxiliary engines contribute 3.8%-8.3% of PM2.5 in Metro Kaohsiung.