Study of Thermal Behavior of Moxa Floss Using Thermogravimetric and Pyrolysis-GC/MS Analyses

Abstract

Moxa floss is a type of biomass used as the main combustion material in moxibustion, a therapy that applies heat from moxa floss combustion to points or body areas for treatment. Safety concerns regarding moxa smoke have been raised in recent years. Since moxa floss is the source material in moxibustion, its thermal behavior and pyrolysis products would be related to the products formed in moxa smoke. This work aims to understand the thermal behavior of moxa floss and investigate the pyrolysis products generated from moxa floss combustion. Six commercial moxa floss samples of 3 storage years and 10 storage years, and of low, medium, and high ratios, were selected. The kinetic data from moxa floss combustion was carried out by a thermogravimetric analyzer. Pyrolysis-gas chromatography and mass spectroscopy using a gas chromatograph and mass spectrometer equipped with a pyroprobe were used to examine the pyrolysis products. Thermogravimetric profiles for all the samples were overall similar and showed a monotonic weight decrease. The range of intensive reaction temperature occurred between 150°C and 450°C, which was characterized by a major weight loss and accompanied by an exothermal degradation of the main components. The average ignition temperature for the samples of 3 and 10 storage years was 218.3°C and 222.6°C, respectively, which was lower than most herbaceous plants. The identified pyrolysis products include monocyclic aromatic hydrocarbons, polycyclic aromatic hydrocarbons, ketones, acids, and alkanes. All were of relatively low intensities of below 5% in relative abundance. No volatiles were detected in the samples of 10 storage years. The relatively low values of ignition temperature suggested that moxa floss is more combustible and can be ignited more easily than other herbaceous plants. This may explain why moxa floss has remained as the preferred material used for moxibustion over the years.

Efficacy and Safety of a Novel Plum Blossom Needling with Mild Moxibustion Device for Upper Limb Pain Disorder and Motor Dysfunction in Patients with Stage 1 Post-Stroke Shoulder-Hand Syndrome: Study Protocol for a Multi-Center, Single-Blind, Randomized Sham-Controlled Trial

“…[58][59][60][61][62][63] Therefore, our hypothesis is that the efficacy and safety of MS possibly should be affected by the level of MSC, moxa quality and duration of exposure in MS. Firstly, moxa aged more than three years is considered as quality guarantee for its characteristics, and the moxibustion duration usually lasts for 20-30 min for each session. 64 Hence, moxa that has been aged for three years will be utilized in 30-minute treatment sessions in this trial.…”

Efficacy of Moxibustion Smoke for Stage 1 Post-Stroke Shoulder-Hand Syndrome: Protocol for a Multi-Center, Single-Blind Randomized Sham-Controlled Trial

“…In this clinical trial, moxa floss that has been aged for five years will be utilized, in order to ensure an even higher standard of quality and safety. 31 Few studies have been published that address the ideal duration of exposure to MS. One study found that exposure to moxibustion at a MSC level of 2.5 ± 0.5 mg/m 3 twice in one week, for 25 minutes per session, induced no significant adverse effects on heart rate or heart rate variability in young, healthy adults. 53 A cross-sectional survey of 803 acupuncturists in China who regularly practice moxibustion treatment, using the American Thoracic Society Division of Lung Disease questionnaire (ATS-DLD-78-A), showed that long-term, regular exposure to MS did not appear to have a significant causal relationship with respiratory diseases and symptoms in these practitioners.…”

“…According to clinical experience accumulated by doctors over many centuries in China, it is felt that Folium Artemisiae argyi that has been aged for at least three years is the most suitable material for moxibustion. 31 The mass concentration of particulate matter (PM) generated with an aerodynamic diameter of less than 10 mm (PM 10 ) has been evaluated in some studies in order to quantify MSC and evaluate the degree of air pollution produced during moxibustion. 29 , 32 According to one noteworthy study conducted in Beijing and Tianjin, China, the average PM 10 produced in a typical moxibustion treatment in China, using standard materials in an enclosed room, was observed to be 3.54 mg/m 3 .…”

The Mechanism Study of Moxa Combustion Products on Regulating Vascular Endothelial Function in Atherosclerotic Mice

“…Artemisinin is the medicine for treating malaria. Artemisia argyi , like Artemisia annua , belongs to the genus of composite and is the main material of moxibustion [ 13 ]. The clinical application of moxibustion and MS was recorded in “Handbook of Prescription for Emergency.” The original text was “in order to cut off the spread of pestilence, the moxa floss can be ignited and placed around the patient's bed to eliminate the virus infection.” Since the outbreak of the COVID-19 in 2020, MS has been used to sterilize the air in China and is also reported to have anti-inflammatory effect to regulate autonomic functions [ 14 – 17 ].…”

“…Artemisinin is the medicine for treating malaria. Artemisia argyi, like Artemisia annua, belongs to the genus of composite and is the main material of moxibustion [13]. e clinical application of moxibustion and MS was recorded in "Handbook of Prescription for Emergency.…”