Characterization of risks and pathogenesis of respiratory diseases caused by rural atmospheric PM2.5

Key toxicity enhancement effect of aqueous-phase secondary formation: Insights from hourly measurements during haze events

Haze events pose substantial health risks, yet the link between the chemical composition of particulate matter (PM) and the exacerbated health impacts during such episodes remains unclear. This study conducted hourly off-line measurements of the chemical composition and oxidative potential (OP) of water-soluble fractions (WSF) of PM2.5 during three haze episodes in the North China Plain (NCP). Results revealed that water-soluble inorganic ions were the primary contributors to the increase in WSF mass (60.8 %), while water-soluble organic carbon (WSOC) was the key driver of OP enhancement, accounting for 78.7 % of OP per unit WSF mass (OPm). Molecular characterization via excitation-emission matrix spectroscopy (EEM) and high-resolution mass spectrometry (Orbitrap) identified highly oxygenated humic-like substances (HO-HULIS) as the major contributors to OPm (43 %). Notably, secondary organic aerosol (SOA)-related HO-HULIS, including highly oxygenated and unsaturated compounds, oxygenated/nitro polycyclic aromatic hydrocarbons (o/n-ConA), and oxygenated/nitro polyphenols (o/n-Poly), were identified as key toxic components. Source apportionment (PMF) analysis indicated that secondary organic aerosols (SOA), particularly those formed through aqueous-phase reaction, contributed 64.8 % of OPm, underscoring the critical role of aqueous-phase SOA in health risk enhancement during haze events.

Moderating effect of green space on relationship between atmospheric particulate matter and cardiovascular and cerebrovascular disease mortality in Ningxia, China

OBJECTIVE

This study explores the moderating effect of green space on the association between atmospheric particulate matter (PM) and cardiovascular and cerebrovascular disease (CCVD) mortality.

METHODS

Data on CCVD mortality, PM, meteorological factors, and the Normalized Difference Vegetation Index (NDVI) of green spaces in Ningxia from 2010 to 2020 were collected. A time-series generalized additive mixed-effect model (GAMM) was applied to analyze the exposure-response relationship between PM and CCVD mortality. The moderating effect of green spaces was examined using green space buffers of different radii (300 m, 500 m, 1000 m, and 2000 m) and density.

RESULTS

There were 150,356 CCVD deaths in Ningxia during the study period. The annual mean concentrations of PM2.5 and PM10 were 44.44 μg/m³ and 105.30 μg/m³, respectively, with an annual mean NDVI value of 0.25 within a 500 m radius buffer. An increase of 10 μg/m³ in PM2.5 and PM10 concentrations was significantly associated with an elevated risk of CCVD mortality, with the strongest excess risk (ER) observed at lag07 lag. The ER for PM2.5 was 1.43% (95% CI: 0.97%, 1.89%), and for PM10 was 0.55% (95% CI: 0.38%, 0.72%). The interaction analysis indicated that higher green space density could moderate the association between PM exposure and CCVD mortality risk. and as the green space buffer zone expanded, the interaction on CCVD mortality risk progressively strengthened. The independent moderation analysis indicated that an increase in green space buffer zone was associated with a reduced risk, and as green space density increased from Q1 to Q3, the ER for PM2.5-related CCVD mortality decreased from 1.56% to 0.6%, while the ER for PM10-related CCVD mortality decreased from 0.53% to 0.09%. In conclusion, atmospheric PM is associated with increased CCVD mortality risk, while larger green space buffers and higher green space density significantly moderated this association.

Estimating the spatiotemporal distribution of PM2.5 concentrations in Tianjin during the Chinese Spring Festival: Impact of fireworks ban

SETTING

off fireworks during the Spring Festival (SF) is a traditional practice in China. However, because of its environmental impact, the Chinese government has banned this practice completely. Existing evaluations of the effectiveness of firework prohibition policies (FPPs) lack spatiotemporal perspectives, making it difficult to comprehensively assess their effects on air quality. Consequently, this study used remote sensing technology based on aerosol optical depth and multiple variables, compared nine statistical learning methods, and selected the optimal model, transformer, to estimate daily spatiotemporal continuous PM2.5 concentration datasets for Tianjin from 2016 to 2020. The overall model accuracy reached a root mean square error of 15.30 μg/m³, a mean absolute error of 9.55 μg/m³, a mean absolute percentage error of 21.07%, and an R2 of 0.88. Subsequently, we analysed the variations in PM2.5 concentrations from three time dimensions-the entire year, winter, and SF periods-to exclude the impact of interannual variations on the experimental results. Additionally, we quantitatively estimated firework-specific PM2.5 concentrations based on time-series forecasting. The results showed that during the three years following the implementation of the FPPs, firework-specific PM2.5 concentrations decreased by 52.70%, 49.76%, and 86.90%, respectively, compared to the year before the implementation of the FPPs. Spatially, the central urban area and industrial zones are more affected by FPPs than the suburbs. However, daily variations of PM2.5 concentrations during the SF showed that high concentrations of PM2.5 produced in a short period will return to normal rapidly and will not cause lasting effects. Therefore, the management of fireworks needs to consider both environmental protection and the public's emotional attachment to traditional customs, rather than simply imposing a blanket ban on fireworks. We advocate improving firework policies in four aspects-production, sales, supervision, and control-to promote sustainable development of the ecological environment and human society.

Disease types and pathogenic mechanisms induced by PM2.5 in five human systems: An analysis using omics and human disease databases

Atmospheric fine particulate matter (PM2.5) can harm various systems in the human body. Due to limitations in the current understanding of epidemiology and toxicology, the disease types and pathogenic mechanisms induced by PM2.5 in various human systems remain unclear. In this study, the disease types induced by PM2.5 in the respiratory, circulatory, endocrine, and female and male urogenital systems have been investigated and the pathogenic mechanisms identified at molecular level. The results reveal that PM2.5 is highly likely to induce pulmonary emphysema, reperfusion injury, malignant thyroid neoplasm, ovarian endometriosis, and nephritis in each of the above systems respectively. The most important co-existing gene, cellular component, biological process, molecular function, and pathway in the five systems targeted by PM2.5 are Fos proto-oncogene (FOS), extracellular matrix, urogenital system development, extracellular matrix structural constituent conferring tensile strength, and ferroptosis respectively. Differentially expressed genes that are significantly and uniquely targeted by PM2.5 in each system are BTG2 (respiratory), BIRC5 (circulatory), NFE2L2 (endocrine), TBK1 (female urogenital) and STAT1 (male urogenital). Important disease-related cellular components, biological processes, and molecular functions are specifically induced by PM2.5. For example, response to wounding, blood vessel morphogenesis, body morphogenesis, negative regulation of response to endoplasmic reticulum stress, and response to type I interferon are the top uniquely existing biological processes in each system respectively. PM2.5 mainly acts on key disease-related pathways such as the PD-L1 expression and PD-1 checkpoint pathway in cancer (respiratory), cell cycle (circulatory), apoptosis (endocrine), antigen processing and presentation (female urogenital), and neuroactive ligand-receptor interaction (male urogenital). This study provides a novel analysis strategy for elucidating PM2.5-related disease types and is an important supplement to epidemiological investigation. It clarifies the risks of PM2.5 exposure, elucidates the pathogenic mechanisms, and provides scientific support for promoting the precise prevention and treatment of PM2.5-related diseases.

Health assessment of emerging persistent organic pollutants (POPs) in PM2.5 in northern and central Taiwan

Over the last two decades, Taiwan has effectively diminished atmospheric concentrations of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) through the adept utilization of advanced technologies and the implementation of air pollution control devices. Despite this success, there exists a dearth of data regarding the levels of other PM2.5-bound organic pollutants and their associated health risks. To address this gap, our study comprehensively investigates the spatial and seasonal variations, potential sources, and health risks of PCDD/Fs, Polychlorinated biphenyls (PCBs), and Polychlorinated naphthalene (PCNs) in Northern and Central Taiwan. Sampling collections were conducted at three specific locations, including six municipal waste incinerators in Northern Taiwan, as well as a traffic and an industrial site in Central Taiwan. As a result, the highest mean values of PM2.5 (20.3-39.6 μg/m3) were observed at traffic sites, followed by industrial sites (14.4-39.3 μg/m3), and the vicinity of the municipal waste incinerator (12.4-29.4 μg/m3). Additionally, PCDD/Fs and PCBs exhibited discernible seasonal fluctuations, displaying higher concentrations in winter (7.53-11.9 and 0.09-0.12 fg I-TEQWHO/m3) and spring (7.02-13.7 and 0.11-0.16 fg I-TEQWHO/m3) compared to summer and autumn. Conversely, PCNs displayed no significant seasonal variations, with peak values observed in winter (0.05-0.10 fg I-TEQWHO/m3) and spring (0.03-0.08 fg I-TEQWHO/m3). Utilizing a Positive Matrix Factorization (PMF) model, sintering plants emerged as the predominant contributors to PCDD/Fs, constituting 77.9% of emissions. Woodchip boilers (68.3%) and municipal waste incinerators (21.0%) were identified as primary contributors to PCBs, while municipal waste incinerators (64.6%) along with a secondary copper and a copper sludge smelter (22.1%) were the principal sources of PCNs. Moreover, the study specified that individuals aged 19-70 in Northern Taiwan and those under the age of 12 years in Central Taiwan were found to have a significantly higher cancer risk, with values ranging from 9.26 x 10-9-1.12 x 10-7 and from 2.50 x 10-8-2.08 x 10-7respectively.