Characteristics of selected indoor air pollutants from moxibustion

Concentrations and risk of monoaromatic hydrocarbons (MAHC), formaldehyde (HCHO), and polycyclic aromatic hydrocarbons (PAHs) in two moxibustion rooms were determined. The mean concentrations of MAHC, HCHO and PAHs were 535.2 μg/m3, 157.9 μg/m3 and 12.86 μg/m3, respectively, with notable health risks, indicating relatively serious pollution in indoor air due to the use of burning moxa. The indoor emissions of target pollutants from burning moxa in test chamber were also investigated. Toluene, benzene and xylene appeared to be dominant MAHCs, and naphthalene (NA) the dominant PAH, which were consistent with the pollution levels of the detected moxibustion rooms. The emission characteristics of smoky moxa and mild moxa were much in common and relatively close to that of tobacco; while that of smoke-free moxa showed a distinction. Though pollutants emission patterns varied within the three types of moxa, all of them had apparently higher emission intensities than other typical indoor sources, including tobacco. The results of this study can offer some references during the selection of moxa sticks and application of moxibustion.