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Community Multiscale Air Quality Modeling System (CMAQ)

Understanding the emissions and criteria pollutant formation from Volatile Chemical Products (VCPs)

Stock photo of cosmetic bottles on a shelf

Volatile organic compounds (VOCs) from adhesives, cleaning agents, personal care products, paints, pesticides, and other volatile chemical products (VCPs) result in human exposure in the vicinity of product use. Evaporated VOCs also react in the atmosphere to produce secondary pollutants including ozone and secondary organic aerosol (SOA), a contributor to PM2.5. While VOCs from these sources have been part of the EPA National Emission Inventory (NEI) for decades, reductions in tailpipe VOC emissions mean that this source is of increasing interest for air quality in urban locations. Southern California is one such location that experiences ozone concentrations persistently in excess of the National Ambient Air Quality Standard (NAAQS) and where the EPA Community Multiscale Air Quality (CMAQ) model largely underestimates the organic portion of PM2.5 in most air quality management applications. Current and ongoing work at EPA seeks to understand the magnitude of emissions from VCPs as well as the chemical reactions that result in criteria pollutant formation.