Abstracts: ISEE 22nd Annual Conference, Seoul, Korea, 28 August-1 September 2010: Air Pollution - Exposure Characterization and Health Effects
Peking University, Beijing, People's Republic of China.
Abstracts published in Epidemiology have been reviewed by the societies at whose meetings the abstracts have been accepted for presentation. These abstracts have not undergone review by the Editorial Board of Epidemiology.
Volatile organic compounds (VOCs) may result in adverse health effects and are regarded as important indoor air pollutants. Although there are many studies about indoor VOCs, little is associated with VOCs pollution in the hospitals, especially waiting areas. This study is aimed to investigate the pollution status and explore the sources of VOCs in hospital waiting areas.
Samples were collected from 9 waiting areas of 3 hospitals in Beijing. According to the prevalence, abundance, and toxicity, 65 target compounds were detected and quantified by preconcentrator-GC/MS system. Indoor/outdoor ratios, correlation analysis, and principal component analysis (PCA) were performed to investigate the characteristics of emission sources.
More than 100 VOCs species were detected in indoor and outdoor air. The average VOCs concentration was 123.64–713.22 μg/m3. Toluene, xylenes, ethylene, and benzene were the most abundant aromatics with indoor concentrations significantly higher than that of outdoors except benzene. High levels of toluene and xylenes were found exceeding the indoor air standard of China (2003) in some waiting areas. Strong correlation between indoor and outdoor air for benzene, n-hexane, and toluene was observed in indoor air with low indoor–outdoor ratio values. VOCs like n-nonane, decane, undecane, m/p-xylene, and tetrachlorethylene were about 3–4 times the concentration of outdoor air with weak correlation. Three factors were extracted by PCA from outdoor samples and accounted for 62.03%, 17.70%, and 10.23% of the variance, respectively. For the indoor samples, the PCA identified 4 factors that explained 36.24%, 21.86%, 18.01%, and 9.05% of the variance, respectively.
This study present a clear picture of the characteristics of VOCs in different waiting areas of hospitals. The major components were aromatics, alkanes, and alkenes that accounted for 61%–98% of the total contents. The indoor–outdoor values of most VOCs exceeded 1, indicating that indoor sources existed. Variability in indoor waiting areas was dominated by compounds associated with construction materials and furnishings followed by diesel emission, cleaning products, and industrial emission.