Lung Function Decline after 24 Weeks of Moxa Smoke Exposure in Rats.

Area of Science:

• Pulmonary Medicine
• Toxicology
• Traditional Chinese Medicine

Background:

• Moxibustion, a traditional therapy, involves burning moxa, which generates smoke containing inhalable particulates.
• Smoke inhalation is increasingly linked to adverse respiratory health outcomes.
• Understanding the specific effects of moxa smoke on lung function is crucial for safety assessments.

Purpose of the Study:

• To investigate the impact of varying moxa smoke concentrations on the pulmonary function of Wistar rats.
• To establish a dose-response relationship between moxa smoke exposure and lung function parameters.

Main Methods:

• A randomized block design experiment involving 28 male Wistar rats divided into control and three moxa smoke exposure groups (low, medium, high concentrations).
• Rats were exposed to moxa smoke (27.45–384.67 mg/m³) for 20 minutes daily over 24 weeks.
• Lung function was assessed using the AniRes 2005 animal pulmonary function system.

Main Results:

• No mortality was observed across all experimental groups.
• No significant differences were found in forced expiratory volume in one second/forced vital capacity percentage (FEV1/FVC%), inspiratory resistance (Ri), or expiratory resistance (Re).
• Dynamic compliance (Cdyn) significantly decreased in medium and high concentration groups compared to controls, while the low concentration group showed no significant change.

Conclusions:

• Moxa smoke exposure at low concentrations (27.45 mg/m³) did not impair rat lung function.
• Medium and high concentrations of moxa smoke demonstrably reduced lung function, indicated by decreased dynamic compliance.
• The study suggests that higher concentrations of moxa smoke may pose a risk to lung health, warranting further safety evaluations.