Large contributions of anthropogenic sources to amines in fine particles at a coastal area in northern China in winter

Amines in fine particles constitute a significant fraction of secondary organic aerosols and have adverse effects on air quality and human health. To understand the chemical composition, variation characteristics, and potential sources of fine particulate amines in the coastal area in northern China, field sampling and chemical analysis were conducted in coastal Qingdao in the winter of 2018 and 2019. A total of 15 major amines were identified and quantified by using an ultra-high-performance liquid chromatography coupled with mass spectrometry. The average concentration of total amines in PM2.5 samples was approximately 130 ng m−3. Dimethylamine was the most abundant species with average fractions of 44.8% and 65.0% in the quantified amines during the two field campaigns, followed by triethylamine (22.9% and 8.7%) and methylamine (8.3% and 4.4%). The amines in PM2.5 usually exhibited elevated concentrations in the presence of high levels of SO2 and NOx or in the condition of high relative humidity. A receptor model of positive matrix factorization was employed and seven major sources were identified, including coal combustion, industrial production, vehicle exhaust, biomass burning, agricultural activities, secondary formation, and marine emission. Surprisingly, most of 15 amines in fine particles primarily originated from the primary emissions of anthropogenic activities particularly related to coal combustion and industrial productions, which should be given close concern to address the amine pollution.