Source Profiles and Chemical Reactivity of Volatile Organic Compounds from Solvent Use in Shanghai, China

Chamber experiments, exhaust collection, and in-situ sampling were employed to study the emission profiles of volatile organic compounds (VOCs) from solvent use, specifically indoor paint, auto paint, furniture paint, and print ink, which are of significant importance with regard to VOC emissions in Shanghai. The results showed that there were some differences among these VOC source profiles of the emissions associated with different solvents. On the one hand, for emissions from imported indoor solvents, similar to 50% of the total mass concentration was contributed by aromatics, and similar to 30% by alkanes. On the other hand, VOC source profiles from domestic indoor paint, furniture paint, and auto paint were similar in the sense that aromatics made a much larger contribution to total VOCs, specifically, 98% for domestic indoor paint, 80%-93% for the other two, and C8-C9 aromatics accounted for similar to 70% of total VOCs. For VOCs from printing, C2-C5 species dominated by more than 50%, followed by C8-C9 aromatics. VOCs from the use of different solvents presented different chemical reactivities. Among the four solvents listed above, the average OH loss rate constant (k-avg) and maximum incremental reactivity (MIR-avg) of VOCs from printing were the lowest, with values of 8.2 x 10(-12) cm(3)/molecule/s and 2.9 g(O-3)/g(VOC), respectively. For VOCs from painting, the average reactivity was twice that of VOCs from printing, and its value of MIR-avg was 4.7-6.3 g(O-3)/g(VOC). There are significant variations in the VOC source profiles related to solvent use in different studies. The representativeness of the solvents studied and the VOC samples collected should thus be more closely examined. The accuracy of VOC source profiles related to solvent use is highly dependent on location and sampling frequency.