Variation of PM2.5 and PM10 in emissions and chemical compositions in different seasons from a manure-belt laying hen house

Duck House Inhalable Particulate Matter Induces Lung Injury by Activating Ferroptosis

The particulate matter (PM) generated during poultry farming is characterized by its complex composition and substantial emission levels. However, researches on the respiratory damage caused by poultry house PM and the underlying mechanisms remain limited. In this study, inhalable PM collected from duck houses was administered to experimental mice through inhalation exposure. After 10 days of short-term exposure and 30 days of long-term exposure, mice samples were collected for lung histopathological analysis and inflammatory cytokines detection. The results showed that inhalation of duck house PM induced pulmonary and systemic inflammatory responses in both groups of mice, with significant upregulation of IL-6 and CXCL2. Compared to short-term exposure, long-term exposure resulted in more severe microscopic lesions in the lungs. In addition, the concentrations of malondialdehyde (MDA) and glutathione (GSH) increased in mice, indicating that duck house PM could trigger oxidative stress in lungs, we also found duck house PM induced ferroptosis in mice. Furthermore, it was confirmed that duck house PM caused cell damage and increased intracellular iron levels in MLE-12 cells, and PM reduced GSH in a dose-dependent manner. Notably, ferroptosis inhibitor treatment effectively alleviated PM-induced cell damage. These findings indicated that duck house PM can induce ferroptosis in both mice and cells, and ferroptosis plays a critical role in duck house PM-induced lung damage. These results laid a solid foundation for further exploring the mechanism of PM-induced lung injury, and providing a new insight for targeting ferroptosis to treat such damage.

Time series analysis of PM2.5 pollution risk based on the supply and demand of PM2.5 removal service: a case study of the urban areas of Beijing

Demonstrating the temporal changes in PM2.5 pollution risk in regions facing serious PM2.5 pollution problems can provide scientific evidence for the air pollution control of the region. However, research on the variation of PM2.5 pollution risk on a fine temporal scale is very limited. Therefore, we developed a method for quantitative characterizing PM2.5 pollution risk based on the supply and demand of PM2.5 removal services, analyzed the time series characteristics of PM2.5 pollution risk, and explored the reasons for the temporal changes using the urban areas of Beijing as the case study area. The results show that the PM2.5 pollution risk in the urban areas of Beijing was close between 2008 and 2012, decreased by approximately 16.3% in 2016 compared to 2012, and further decreased by approximately 13.2% in 2021 compared to 2016. The temporal variation pattern of the PM2.5 pollution risk in 2016 and 2021 showed significant differences, including an increase in the number of risk-free days, a decrease in the number of heavily polluted days, and an increase in the stability of the risk day sequence. The significant reduction in risk level was mainly attributed to Beijing's air pollution control measures, supplemented by the impact of COVID-19 control measures in 2021. The results of PM2.5 pollution risk decomposition indicate that compared to the previous 2 years, the stability and predictability of the risk variation in 2016 increased, but the overall characteristics of high risk from November to February and low risk from April to September did not change. The high risk from November to February was mainly due to the demand for coal heating during this period, a decrease in PM2.5 removal service supply caused by plant leaf fall, and the common occurrence of temperature inversions in winter, which hinders the diffusion of air pollutants. This study provides a method for the analysis of PM2.5 pollution risk on fine temporal scales and may provide a reference for the PM2.5 pollution control in the urban areas of Beijing.

Lnc-Clic5 as a sponge for miR-212-5p to inhibit cow barn PM2.5-induced apoptosis in rat alveolar macrophages

Particulate matter 2.5 (PM2.5) is a highly hazardous airborne particulate matter that poses a significant risk to humans and animals. Urban airborne particulate matter contributes to the increased incidence and mortality of respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD), in humans. However, the specific mechanism by which PM2.5 affects animals in barn environments is yet to be elucidated. In this study, we investigated the effect of exposure to cow barn PM2.5 on rat alveolar macrophages (NR8383) and found that it induced apoptosis via the miR-212-5p/RASSF1 pathway. We found that lnc-Clic5 expression was downregulated in NR8383 cells exposed to cow barn PM2.5. Lnc-Clic5 plays a competitive endogenous RNA (ceRNA) regulatory role by sponging miR-212-5p to attenuate the regulation of RASSF1. Moreover, lnc-Clic5 overexpression inhibited NR8383 apoptosis by targeting the miR-212-5p/RASSF1 pathway. Co-treatment with miR-212-5p and lnc-Clic5 in the presence of cow barn PM2.5 revealed that lnc-Clic5 reversed NR8383 cell apoptosis induced by PM2.5 when miR-212-5p was overexpressed. These findings contribute to the study of ncRNAs and ceRNAs regulating PM2.5-induced apoptosis in animal farms, provide therapeutic targets for lung macrophage apoptosis, and may be useful for further evaluating the toxicological effects of PM2.5 in farmhouses on the respiratory systems of humans and animals.