Air Quality Atmosphere and Health最新文献

Seasonal patterns and potential exposure of size-segregated particulate matter (PM) were studied in central Delhi from January 2021 to December 2022. A total of 79 samples were collected using an eight-stage Andersen cascade impactor. The samples were categorized as submicron (PM_{< 0.43–1.1}), fine (PM_1.1–2.1), and coarse (PM_2.1- > 9) fractions of PM. During 2021, average mass concentrations of submicron, fine, and coarse PM were 67.2 ± 10.7, 33.6 ± 5.7 and 124.1 ± 9.1 µg/m³ respectively. During 2022, the corresponding average mass concentrations were 55.1 ± 7.5, 25.8 ± 3.6 and 117.2 ± 8.9 µg/m³ respectively. The submicron and fine particles were more prevalent during the post-monsoon and winter seasons, while coarse particles were more pronounced during summer. The lognormal mass-size distribution displayed a bimodal pattern during the winter and the post-monsoon seasons of 2021 and 2022. Conversely, summer and monsoon seasons exhibited unimodal distributions. The inhalation dose was calculated for all seasons, found in the order post-monsoon > winter > summer > monsoon. Total, regional, and lobar depositions of size-segregated PM in respiratory airways of various age groups were also quantified using the multiple-path particle dosimetry model. Among different age groups, the deposited concentrations ranged from 35–51% for inhaled submicron particles, 57–68% for fine particles, and 89–96% for coarse particles, respectively. The deposited mass in respiratory airways was maximum for coarse particles in summer, while maximum in winter for submicron and fine particles in all age groups. Concentration weighted trajectory analysis for various size ranges in different seasons highlighted the influence of local, regional, and long-range transport of pollutants at the receptor site.

Fine particulate matter (PM_2.5) has been shown to cause oxidative stress, which has negative health consequences. The oxidative potential (OP) of PM_2.5, a promising health exposure metric, was assessed in five Colombian cities using the synthetic respiratory tract lining fluid assay that tracks the depletions of glutathione and ascorbate. For this, a set of 91 integrated 2-week ambient PM_2.5 samples were collected using Ultrasonic Personal Aerosol Samplers (UPAS) at background (5), traffic (37), industrial (12) and residential (37) sites. Across all site types, mean PM_2.5 mass concentration was 20.20 ± 9.36 µg m^− 3. The oxidative potential (OP^AA for ascorbate and OP^GSH for glutathione) varied widely across cities with an average of 2.67 ± 1.27 for AA and 2.93 ± 1.22 % depletion m^− 3 for GSH. OP metrics among cities were not correlated with PM_2.5 mass concentrations. Overall, industrial sites showed higher PM_2.5 mass concentrations and OP^AA. In contrast, OP^GSH was not found to differ among industrial, traffic, or residential sites, but was lower for background sites. Our findings provide substantial evidence of variations in PM_2.5 OP between cities and within the cities. Further research is needed to assess the association between OP and adverse health effects, as well as to attribute the sources that cause such variations.

Electronic cigarettes (e-cigarettes) are a growing public health concern. Vaping liquids used in e-cigarettes emit a range of chemicals, including potentially hazardous volatile organic compounds (VOCs). Exposure to VOCs is associated with adverse effects including asthma attacks, neurological disorders, and increased risk of cancer. This study investigated the VOCs emitted into the headspace of a gas chromatograph/mass spectrometer from e-cigarette vaping liquids, identified potentially hazardous compounds, and compared emissions between regular and organic versions. Vaping liquids (n = 25) were randomly selected from the market and analysed for their volatile emissions using headspace gas chromatography/mass spectrometry. The products were available for sale in the US, Australia, and New Zealand, and included regular (flavoured and flavourless) and organic (flavoured) versions. Results revealed that the vaping liquids collectively emitted 162 VOCs with 47 classified as potentially hazardous. Notably, all of the flavoured vaping liquids (regular and organic) emitted one or more VOCs classified as potentially hazardous. Further, among the 47 VOC occurrences classified as potentially hazardous, none were listed on any vaping liquid label or related product website. We found no significant difference in VOCs emitted between the regular (flavoured) and organic (flavoured) vaping liquids, and 40% of the hazardous VOCs detected were the same among these regular and organic versions. This study adds to the growing body of evidence that vaping liquids are a source of exposure to numerous volatile compounds, including potentially hazardous VOCs such as benzene, toluene and xylene. Moreover, the long-term health effects of vaping liquids are not well understood, highlighting the need for improved information on ingredients and health risks.

Environmental pollution has become highly important for countries and societies because climate change and global warming are stimulated by increasing carbon dioxide (CO₂) emissions. Hence, all related parties have been searching for solutions. Considering the high role of energy use in causing CO₂ emissions, energy-related research and development (R&D) investments are considered a strategic tool to curb the emissions. Accordingly, the study analyzes the effect of energy-related R&D investments on power sector CO₂ emissions. In doing so, the study examines leading R&D investing countries (namely, Canada-CAN; Switzerland-CHE; Germany-DEU; France-FRA; Japan-JPN; Norway-NOR; United States-USA), considering three R&D investment sub-types (i.e., energy efficiency R&D investments-EEF; renewable energy R&D investments-RRD; nuclear energy R&D investments-NRD), uses data from 1985/Q1 to 2022/Q4, and performs Wavelet Local Multiple Correlation (WLMC) approach to analyze over times and frequencies. The results show that (i) the effects of R&D investments are weak (strong) at lower (higher) frequencies; (ii) the effects of R&D investments vary based on times, frequencies, and countries; (iii) the most dominant R&D type is EEF (CHE, DEU, FRA, & JPN), RRD (CAN & NOR), and NRD (USA); (iv) there is an important externality among R&D types. Thus, the findings reveal the time, frequency, and country-based varying effect of R&D investments on power sector CO₂ emissions implying a need for comprehensively balanced planning for R&D investments. Hence, the countries should take the highly effective R&D investment types in combating power sector CO₂ emissions, allocate further budget to the effective ones, and re-consider the budget distribution among the R&D types.

This work studies the elemental seasonal variation in the PM_2.5 obtained from the Monterrey Metropolitan Area with particular emphasis on sulfur species. The existence of these sulfur species was identified in all samples analyzed in this work. The results of this work evidence the formation of surface layers rich in sulfur compounds, which indicates the formation of secondary organic aerosols. This point was confirmed by the highest correlation identified between O₃ concentration and relative humidity with the sulfur wt% in PM_2.5. Additionally, this work proposes a multiple-liner correlation among sulfur wt% formed on PM_2.5 with several pollutants and meteorological conditions, identifying the main contributors to their formation. Results suggest first the formation of sulfite species followed by their oxidation to sulfate species, which are promoted by specific conditions of relative humidity and O₃. Among all evaluated seasons, samples obtained in fall showed the highest amount of sulfur wt% attributable to a synergetic effect between relative humidity and O₃ concentration.

Understanding the risk trade-offs between nitrogen dioxide (NO₂) and ozone (O₃) pollution is crucial for ozone governance. The air quality health index (AQHI) provides a more comprehensive measure of air pollution mixtures. This study used environmental, meteorological, and health data of 13 cities in the Beijing–Tianjin–Hebei region for 2018–2020 to assess the health effects of pollutants during both cold and warm seasons. The study reveals that NO₂ pollution in the cold season (20.4–63.4 µg/m³) is more severe compared to warm season (18.3–49.7 µg/m³), and its concentrations have been decreasing annually in most cities. However, the study also highlights a concerning trend of increasing ozone concentrations during the cold season across all cities in the region (The average annual increase is 3.5 µg/m³). This increase may be linked to the abatement of nitrogen oxides (NO_X) and particulate matter (PM). The health benefit of reducing environmental air NO₂ concentrations maybe offset by the increase in O₃ concentrations. Emission control measures to reduce nitrogen dioxide, sulfur dioxide, and particulate matter levels have been effective in reducing the negative impacts on health caused by air pollution in various cities in the Beijing–Tianjin–Hebei region. It was necessary to construct the cold season AQHI (AQHI-C) and warm season AQHI (AQHI-W) separately in the Beijing–Tianjin–Hebei region, especially for the assessment of health risks during the cold season.

Over six million Americans rely on solid fuels for residential heating, which can result in high concentrations of fine and ultrafine particulate matter (PM). Little is known on the characteristics of indoor PM in rural homes, including lung deposited surface area (LDSA) concentration and metals composition, and whether these characteristics may vary by fuel type.Homes using oil, cordwood, or pellet were recruited into the study. Indoor air quality assessment over 48 h included PM_2.5 and PM₁₀ mass concentration (Purple Air monitors) and ultrafine (LDSA) PM < 1 μm, number concentration, and diameter (Partector). Teflon© or polytetrafluoroethylene (PTFE) filters were used to collect PM mass for metals characterization by inductively coupled plasma mass spectrometry (ICP-MS). Participants completed a time activity diary to link household behaviors to changes in LDSA, particle number, and size distribution.Ten homes completed the study- three used primary oil-fueled furnaces/boilers, four used primarily cordwood, and three used pellet fuel. Activity logs and real time measurements highlighted elevated indoor pollution events such as loading wood stoves and cooking. Maximum indoor air particle number concentrations measured were similar across fuel types, though total average particle concentrations, maximum mass, and LDSA concentrations were highly variable. For individual elements Ca, K, Cu, Cd, and Pb, there was a trend of higher concentrations in cordwood heated home, followed by pellet, and then oil heat.

In recent years, the global environmental landscape has experienced significant shifts, with the need for cleaner, more sustainable energy sources becoming increasingly evident. This transformation is especially apparent in China, where environmental innovation is considered the important influential intensity of the green economy. It has been recognized as a fundamental driver of green growth. Thus, this study anticipates a link between human capital, environmental innovation and environmental regulation by applying the QARDL estimation technique. The findings inferred that human capital, both in the long and short run, positively enhances Chinese ecological innovation. Environmental regulations create an enhancement in short-run environmental innovation. Based on estimation results, the policy suggestions to be put forward; the government has to spend more on education, boost the development of high-level human capital, focus on the emergence of high talents, and support talent promotion methods.

The physical and chemical characterizations of airborne particulate matter (PM) in the ambient air of Dhaka, Bangladesh are reported. The daily average concentrations of PM₁₀ and PM_2.5 ranged from 73 to 416 µg/m³ and 44 to 233 µg/m³, respectively. The characterization was performed using Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), inductively coupled plasma mass spectrometry (ICP-MS), thermogravimetric analysis (TGA), and elemental (i.e., CHNS) analysis. In general, PM_2.5 particles were found to be regular in size and stony spherical in shape, whereas PM₁₀ particles displayed a wide array of morphologies, including irregular particle size and shape with sponge morphology. ICP-MS analysis confirmed the presence of trace metals such as V, Mn, Co, Ni, Cu, Zn, As, Sr, Cd, and Pb in the PM samples. The concentrations of metals in PM₁₀ and PM_2.5 were found to be 220 ± 66 mg/g and 453 ± 113 mg/g, respectively. PM₁₀ was found to contain three times more volatile solvents, water, organic compounds, and microbes compared to PM_2.5. Consolidating all findings, a plausible structure for PM was proposed, wherein a metallic core is encapsulated by an organic shell. This study contributes to understand the composition and mechanism for the formation of PM, shedding light on the complex nature of urban air pollution.

Graphical Abstract