Chemical characteristics of fine particulate matter emitted from commercial cooking

The chemical characteristics of fine particulate matter(PM2.5) emitted from commercial cooking were explored in this study.Three typical commercial restaurants in Shanghai,i.e.,a Shanghai-style one（SHS）,a Sichuan-style one（SCS） and an Italian-style one（ITS）,were selected to conduct PM2.5 sampling.Particulate organic matter（POM） was found to be the predominant contributor to cooking-related PM2.5 mass in all the tested restaurants,with a proportion of 69.1% to 77.1%.Specifically,80 trace organic compounds were identified and quantified by gas chromatography/mass spectrometry（GC/MS）,which accounted for 3.8%-6.5%of the total PM2.5 mass.Among the quantified organic compounds,unsaturated fatty acids had the highest concentration,followed by saturated fatty acids.Comparatively,the impacts of other kinds of organic compounds were much smaller.Oleic acid was the most abundant single species in both SCS and ITS.However,in the case of SHS,linoleic acid was the richest one.ITS produced a much larger mass fraction of most organic species in POM than the two Chinese cooking styles except for monosaccharide anhydrides and sterols.The results of this study could be utilized to explore the contribution of cooking emissions to PM2.5 pollution and to develop the emission inventory of PM2.5 from cooking,which could then help the policymakers design efficient treatment measures and control strategies on cooking emissions in the future.