Comparison of Chinese Herbal Oils and Lemon Oil for Formation of Secondary Organic Aerosol

Received: July 6, 2011
Revised: August 16, 2011
Accepted: August 16, 2011
Download Citation: RIS|BibTeX|https://doi.org/10.4209/aaqr.2011.07.0093  

Cite this article:
Huang, H.L., Sheu, S.C., Wu, Y.Y. and Hsu, D.J. (2011). Comparison of Chinese Herbal Oils and Lemon Oil for Formation of Secondary Organic Aerosol. Aerosol Air Qual. Res. 11: 854-859. https://doi.org/10.4209/aaqr.2011.07.0093

ABSTRACT

Several studies reported that evaporation of fragrant essential oils in an indoor environment may cause the emission of secondary organic aerosols (SOAs). However, the tendency of forming SOAs from the use of Chinese herbal oils has not been reported. This study investigated the formation of SOAs from various Chinese herbal oils when reacting with ozone in a controlled environment chamber under different test conditions. Lemon oil, a fragrant essential oil, was also tested under the identical experimental conditions for comparison. The results showed that the formation of SOAs from Chinese herbal oils was limited, compared with lemon oil. Of the Chinese herbal oils tested, Chinese mulberry and perillae folium oils produced more SOAs than the other oils. GC/MS analysis of the essential oils demonstrated the presence of SOA precursors, such as d-limonene, in Chinese mulberry and perillae folium oils but not in the other Chinese herbal oils. Compared with the tested Chinese herbal oils, evaporation of 1 mL lemon oil in the presence of 30 ppb ozone may cause an increase of 6.4 μg/m³ in indoor PM level in a typical room or office. This study concluded that the use of Chinese herbal oils tested in this study would result in a lower particle concentration in indoor settings compared with fragrant essential oils.

Keywords: Particulate matter (PM); Secondary organic aerosol (SOA); Chinese herbal oil; Fragrant essential oil; Aromatherapy