Safety of smoke generated by Japanese moxa upon combustion

Introduction: Moxibustion is an ancient method of traditional medicine (along with acupuncture) using moxa, or processed mugwort leaves. Both the smoke and heat generated by burning moxa are considered to have therapeutic effects. However, recently there have been reports of harmful substances released in smoke from everyday objects such as scented candles or incense. Therefore it appeared to be important to evaluate the safety of products resulting from the combustion of moxa. Methods: We used three types of commonly used moxa. Experiments were conducted by lighting moxa which had been classified according to their level of refinement. Gases released were collected after igniting moxa. A gas chromatograph mass spectrometer (GC/MS) was used for both qualitative and quantitative analysis. Standard conditions for Japanese therapeutic environments were employed. Results: 1,3-butadiene was present from the smoke at the highest level of concentrations of substances governed by assorted indoor air quality and environmental standards (1,3-butadiene, benzene, toluene, ethylbenzene, and xylene) and fell below maximum values. Also, simulation in an indoor environment with 1,3-butadiene was safely within indoor environmental standards. Conclusion: Our simulation results have shown that quantities of harmful substances released upon combustion of moxa during normal clinical therapy of Japan are below maximum levels. Hence are safe for both patient and practitioner. However we detected few amounts of harmful substances released from moxa. These harmful substances are invariably generated upon combustion, although varieties and quantities vary according to substance. So measures to maintain an appropriately safe work environment must be practiced,even though safety was confirmed. (C) 2016 The Authors. Published by Elsevier GmbH.