Acidic reaction products of monoterpenes and sesquiterpenes in atmospheric fine particles in a boreal forest

Abstract

Biogenic acids were measured in aerosols at the SMEAR II (Station for Measuring Forest Ecosystem-Atmosphere Relations II) station in Finland from June 2010 until October 2011. The analysed organic acids were pinic, pinonic, caric, limonic and caryophyllinic acids from oxidation of α-pinene, β-pinene, limonene, 13-carene and β-caryophyllene, respectively. Due to a lack of authentic standards, the caric, limonic and caryophyllinic acids were synthesised for this study. The mean, median, maximum and minimum concentrations (ngm-3) were as follows: limonic acid (1.26, 0.80, 16.5, below detection limit (