Seasonal variation characteristics of atmospheric peroxyacetyl nitrate (PAN) and its source apportionment in a megacity in southern China.

Owing to its biotoxicity and inductive effect on photochemical pollution, atmospheric peroxyacetyl nitrate (PAN), which is a typical product of atmospheric photochemical reactions, has attracted much research attention. However, to the best of our knowledge, few comprehensive studies have been conducted on the seasonal variation and key influencing factors of PAN concentrations in southern China. In this study, PAN, ozone (O), precursor volatile organic compound (VOC), and other pollutant concentrations were measured online for 1 year (from October 2021 to September 2022) in Shenzhen, a megacity in the Greater Bay Area of China.

Long-term observations of oxygenated volatile organic compounds (OVOCs) in an urban atmosphere in southern China, 2014-2019.

Oxygenated volatile organic compounds (OVOCs) are important precursors and intermediate products of atmospheric photochemical reactions, which can promote the formation of secondary pollutants such as ozone (O) and secondary organic aerosol (SOA). However, there have been few studies on the sources of and long-term variation in ambient OVOCs. This study combined sensitive, near real-time measurements of VOCs by proton transfer reaction-mass spectrometry (PTR-MS) with an improved photochemical age parameterization method to quantify daytime sources of OVOCs in an urban atmosphere in China from 2014 to 2019, permitting the observation of the impacts of emission control strategies that were implemented during this period.

Sources of oxygenated volatile organic compounds (OVOCs) in urban atmospheres in North and South China.

Oxygenated volatile organic compounds (OVOCs) are critical precursors of atmospheric ozone (O) and secondary organic aerosols (SOA). Although China is experiencing increasing O pollution from north to south, understanding the major sources of OVOCs in this region is still limited due to their active photochemical behaviors. In this study, five critical OVOCs at a northern urban site (Beijing) and a southern urban site (Shenzhen) were monitored in summer using proton transfer reaction-mass spectrometry (PTR-MS).