Sources of fine organic aerosol. 1. Charbroilers and meat cooking operations

Abstract

Meat cooking operations are a major source of organic aerosol emissions to the urban atmosphere, comprising up to 21 % of the primary fine organic carbon particle emissions in the Los Angeles area. In the present study, the chemical composition of meat smoke aerosol is examined by high-resolution gas chromatography and gas chromatography/ mass spectrometry. The objective is to search for molecular markers that will confirm the presence of meat smoke aerosol in urban atmospheric samples. More than 75 organic compounds are quantified, including the series of the n-alkanes, n-alkanoic acids, n-alkenoic acids, dicarboxylic acids, n-alkanals, n-alkenals, n-alkanones, n-alkanols, furans, lactones, amides, nitriles, polycyclic aromatic hydrocarbons, steroids, and pesticide residues. Prominent among the compounds emitted are n-hexadecanoic acid (i.e., palmitic acid), n-octadecanoic acid (i.e., stearic acid), cis-9-octadecenoic acid (i.e., oleic acid), nonanal, 2-octadecanal, 2-octadecanol, and cholesterol. Although cholesterol can be emitted from other sources, cholesterol concentrations measured in the West Los Angeles atmospheric aerosol are consistent with the cholesterol mass emission rates determined from meat cooking source tests.