A combined dynamic inhalation device designed for moxa-smoking toxicity testing

OBJECTIVE: To design a combined dynamic inhalation device for testing the toxicity induced by moxa smoking.METHODS: The new apparatus(Patent No.201120101911.5) includes air renewal and recycling systems, a gas generating device, a gas control unit, and a device to measure and control temperature and humidity. Sprague-dawley rats were tested for acute and sub-chronic toxicity after exposure to moxa-burning smoke.RESULTS: We found an LC50 of 1.2 × 104mg/m3 in the acute toxicity assays. In sub-chronic toxicity tests the organ coefficients studied showed no sig-nificant differences within rats groups of the same gender after treatment with moxa smoke or a month of recovery. However, mean gray degree of lung 70 heat shock protein(HSP70) was significantly elevated in the high dose group in comparison with the low dose group(P < 0.05); mean gray degree, mean optical density, gross area of HSP70 in other organs and caspase-9 parameters showed no significant differences between groups.CONCLUSION: These results suggest that moxa smoke had no overt toxicity in rats. This work provides evidence and reference for the design of dynamic inhalation exposure systems.