Emissions of Volatile Chemical Products (VCPs) in China: An Updated High-Resolution Mass-Balance-Based Inventory

Abstract

Emmision of Volatile chemical products (VCPs) China: An Updated High-Resolution Mass Balance-Based Invenotry have emerged as a significant source of organic compound emissions in China, contributing to ozone and secondary organic aerosol (SOA) formation. Previous work established the VCP emission inventory by the mass balance (MB) method in China from 2000 to 2017, but localized component emissions and spatial variations have not been systematically investigated. This study presents a high-resolution VCP-gridded emission inventory in China, incorporating an updated method for emission estimation, localized source profiles, and spatial allocation. Results reveal that VCP emissions amounted to 13.88 Tg in 2022, dominated by coatings and adhesives. Industrial and domestic VCPs contribute two-thirds and one-third of total VCP emissions, respectively. Oxygenated volatile organic compounds (OVOCs) and aromatics constitute over 70% of total emissions and ozone formation potential (OFP), with aromatics (3.86 Tg, primarily from coatings) contributing 17.45 Tg to OFP. The component emissions of VCPs in China exhibit distinct characteristics compared to the United States, marked by higher contributions of aromatics and N/S-containing compounds. Spatial analysis highlights industrial VCP emissions dispersed across suburban regions, whereas domestic VCP emissions are concentrated in urban cores. Key species like m/p-xylene and methanol align with industrial emissions, whereas ethanol and D5-siloxane match domestic emission patterns, indicative of promising application as industrial and domestic VCP tracers, respectively. The model-ready gridded emission inventory for VCP developed in this study can be used by a chemical transport model to evaluate the impacts of VCP emissions on atmospheric chemistry and secondary pollution at different times and spatial scales in China.