PM_2.5 is an important pollutant which affects air quality and human health. In this study, chemical components (water-soluble inorganic ions, organic carbons (OC), elemental carbons (EC), and elemental metals) and health effects were analyzed in wintertime in a suburban area in Hangzhou Bay. OC and SNA (sulfate, nitrate, and ammonium) contributed 76.2% to local PM_2.5. NH₄⁺ existed mainly in the form of (NH₄)₂SO₄ and NH₄NO₃. Seven sources were resolved from PMF analysis, namely secondary inorganic aerosol (31.8%), vehicle exhaust (19.5%), industry mixed with coal combustion (16.3%), crustal dust (9.5%), biomass burning (9.4%), sea salt (8.7%), and the leather industry (4.8%). Potential source contribution function (PSCF) and concentration weighted trajectory (CWT) analysis were applied to study regional transport in this region. Secondary inorganic formation was enhanced from the air plume from the northwest, especially from north Jiangsu Province. The results of the health risk assessment of associated metals indicated the higher potential of Cr and Mn to cause noncarcinogenic effects in children. A significant carcinogenic risk was observed for all people of Cr emitted from the leather industry. Our results showed the chemical characterization and sources of PM_2.5 in a suburban region, the health effects of which should be addressed in future policies to safeguard public health, especially in the leather industry.

While integrating greenhouse gas and air pollutant (AP) mitigation is essential for urban sustainability and public health, municipal-level prioritisation of co-control targets remains hindered by fragmented microdata and decoupled emission inventories. Using Jiaxing—a typical industrialised city in the Yangtze River Delta—as a case study, this work develops a two-dimensional H/G screening framework based on a harmonised 2024 integrated emission inventory and enterprise-level environmental statistics. By converting 54 non-zero source categories into an aggregated matrix, the framework evaluates AP contributions (H-score, averaging PM_2.5, NO_x, SO₂, VOCs, and NH₃) against 100-year global warming potential (GWP₁₀₀)-weighted CO₂-equivalent emissions (G-score). The 70th-percentile screening separates coupled co-control candidates (e.g., combined heat and power, thermal power generation, and motor vehicles) from decoupled, pollutant-specific priorities (e.g., industrial solvent use for VOCs, and paved roads for particulate matter (PM)). Spatial mismatch analysis also contrasted VOC-dominant and CO₂-dominant reporting units, cautioning against a single citywide priority list. Application of an observed 75th-percentile abatement benchmark to reporting industrial enterprises identified a benchmark-implied VOC reduction of 7941 tonnes in 2024. This inventory-based screening framework provides a practical, reproducible methodology to separate integrated-review sources from single-dimension priorities and to identify priority sources for subsequent exposure and health co-benefit assessment.

Ozone (O₃) is a crucial atmospheric component that significantly affects air quality and poses considerable health risks to humans. In the coastal areas of the Yangtze River Delta, typhoons, influenced by the subtropical high-pressure system, can lead to complex ozone pollution situations. This study aimed to explore the causes, sources, and health risks of O₃ pollution during such events. Ground-based data from Jiaxing City’s key ozone precursor (VOCs) composition observations, ERA5 reanalysis data, and models CMAQ-ISAM and PMF were employed. Focusing on the severe ozone pollution event in Jiaxing from 3 to 11 September 2022, the results showed that local ozone production was the main contributor (60.8–81.4%, with an average of 72.3%), while external regional transport was secondary. Concentrations of olefins and aromatic hydrocarbons increased remarkably, playing a vital role in ozone formation. Meteorological conditions, such as reduced cloud cover during typhoon periphery transit, promoted ozone accumulation. By considering the unique respiratory exposure habits of the Chinese population, refined health risk assessments were conducted. Acrolein was found to be the main cause of chronic non-carcinogenic risks (NCRs), with NCR values reaching 1.74 and 2.02 during and after pollution. In lifetime carcinogenic risk (LCR) assessment, the mid-pollution LCR was 1.73 times higher, mainly due to 1,2-dichloroethane and benzene. This study presents a methodology that is readily adaptable to analogous pollution incidents, thereby providing a pragmatic framework to guide actionable local government policy-making aimed at safeguarding public health and mitigating urban ozone pollution.