Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are a class of synthetic organic compounds with extremely high chemical stability and environmental persistence that are widely used in the industrial sector and in consumer goods. Their strong C-F bonds make them difficult to degrade, meaning they can migrate through the atmosphere and settle over long distances, posing long-term risks to the global ecological environment and human health. This article systematically reviews the classification, physicochemical properties, concentration levels, spatial distribution, migration and transformation behaviors, and health and ecological impacts of PFASs in the atmosphere, along with related analytical detection techniques and pollution control methods. Studies show that short-chain PFASs are more likely to migrate through the atmosphere due to their high water solubility and volatility, while long-chain PFASs tend to be adsorbed onto particulate matter and display stronger bioaccumulation. Although atmospheric research on PFASs lags behind that focused on their dynamics in water and soil, the existing data still reveal a difference in their distribution and regional pollution characteristics in the gas and particle phases. Toxicological studies have confirmed that PFAS exposure is associated with liver injury, immunosuppression, developmental toxicity, and cancer risk and can threaten ecological security through the food chain. Currently, governance technologies are confronted with the challenges of low efficiency and high cost. In the future, it will be necessary to combine multi-media models, new analytical techniques, and international collaboration to promote the development of source control and innovative governance strategies.

To investigate the seasonal characteristics, sources, and regional transport patterns of precipitation components in the high-elevation mountainous regions, field sampling was conducted at Mt. Heng (Hunan, South China) from June 2021 to May 2022. In total, 114 precipitation samples were collected and subjected to chemical analysis, including pH, major inorganic ions, and heavy metals. During the study period, the precipitation at Mt. Heng was generally weakly acidic. The concentrations of metals and acidic anions (NO₃⁻ and SO₄²⁻) were higher in the winter and lower in the summer, whereas the concentration of the primary neutralizing cation, NH₄⁺, peaked during the summer. An association was observed between precipitation pH and metal concentrations, whereby acidic precipitation samples exhibited marginally elevated metal concentrations overall. An additional analysis of winter precipitation chemistry at Mt. Heng revealed an increasing trend of ions from 2015 to 2018, followed by a decrease from 2019 to 2021. This trend coincided with the concentrations of NO₂ and SO₂ in the surrounding cities, reflecting the results of clean air actions. The results of the source analysis revealed five major sources: secondary sources (41.5%), coal combustion (24.7%), a mixed source of biomass burning and aged sea salt (11.6%), dust (10.8%), and industrial emissions (11.4%). Backward trajectory cluster analysis revealed that air masses originating from the northern regions were generally more polluted than those from the southern regions. This study provides fundamental data and scientific support for regional atmospheric pollution control and ecological protection in South China.