Contrasts in spatial and temporal variability of oxidative capacity and elemental composition in moxibustion, indoor and outdoor environments in Beijing

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

OBJECTIVE

Moxibustion is a complementary therapy that has been used for thousands of years. Burning moxa produces smoke and inhalable particulates. Recent research has indicated that smoke inhalation is associated with negative lung effects. This study aimed to evaluate the lung function of rats after moxa smoke exposure at different concentrations.

METHODS

Using a randomised block experiment design, 28 male Wistar rats were randomly divided into three moxa smoke groups (opacity) (n=7): low concentration (27.45 mg/m3), medium concentration (168.76 mg/m3), and high concentration (384.67 mg/m3) with a control group. Rats in the moxa smoke groups were exposed in an automatic dynamic exposure device separately with different concentrations for 20 min/d, 6d/week, for 24 weeks. Rats in the control group were exposed in the same space without moxa smoke. Lung function was evaluated by the AniRes 2005 animal pulmonary function analysing system. Statistical Product and Service Solutions 18.0 software was used for data analysis.

RESULTS

In the study, no deaths were found in any group. There was no difference of forced expiratory volume in one second/forced vital capacity percentage (FEV1/FVC%), inspiratory resistance (Ri), and expiratory resistance (Re) among each group after 24 weeks of moxa smoke exposure (P>0.05). Compared with the control group (0.33 ml/cmH20), dynamic compliance (Cdyn) was reduced in the medium (0.29 ml/cmH20) and high (0.25 ml/cmH20) concentration groups (P<0.05); however, Cdyn in the low concentration group (0.29 ml/cmH20) was not significantly affected.

CONCLUSION

Moxa smoke exposure at low concentrations did not affect the rat's lung function. Moxa smoke of medium and high concentrations destroyed the lung function represented by decreased Cdyn. However, moxa smoke of low concentrations (27.45 mg/m3) is much higher than the concentration in a regular moxibustion clinic (3.54 mg/m3). Moxa smoke at higher concentrations might destroy the lung function. The safety evaluation of moxa smoke requires further research.

Concentration characteristics, source apportionment, and oxidative damage of PM2.5-bound PAHs in petrochemical region in Xinjiang, NW China

Polycyclic aromatic hydrocarbons (PAHs) are of considerable concern due to their potential as human carcinogens. Thus, determining the characteristics, potential source, and examining the oxidative capacity of PAHs to protect human health is essential. This study investigated the PM_2.5-bound PAHs at Dushanzi, a large petrochemical region in Xinjiang as well as northwest China. A total of 33 PM_2.5 samples with 13 PAHs, together with molecular tracers (levoglucosan, and element carbon), were analyzed during the non-heating and heating periods. The results showed that the PM_2.5 concentrations were 70.22 ± 22.30 and 95.47 ± 61.73 μg/m³, while that of total PAHs were 4.07 ± 2.03 and 60.33 ± 30.80 ng/m³ in sampling period, respectively. The fluoranthene, pyrene, chrysene, benzo[b]fluoranthene, and benzo[k]fluoranthene were the most abundant (top five) PAHs, accounting for 71.74 and 72.80% of total PAH mass during non-heating and heating periods. The BaP equivalent (BaPeq) concentration exceeded 1 ng/m³ as recommended by National Ambient Air Quality Standards during heating period. The diagnostic ratios and positive matrix factorization indicated that oil industry, biomass burning, coal combustion, and vehicle emissions are the primary sources. The coal combustion remarkably increased during heating period. The plasmid scission assay (PSA) results showed that higher DNA damage rate was observed during heating period. PAHs in PM_2.5 such as Chr, BaP, and IcdP were found to have significantly positive correlations with the plasmid DNA damage rates. Additionally, the relationship among BaPeq and DNA damage rate suggested that synergistic reaction may modify the toxicity of PAHs.

Effect of moxa smoke produced during combustion of Aiye (Folium Artemisiae Argyi) on behavioral changes in mice inhaling the smoke

OBJECTIVE

To evaluate the effects that inhalation of the combustion products of the traditional Chinese herb Aiye (Folium Artemisiae Argyi) has on the central nervous system.

METHODS

Forty Kunming mice (half male) were randomly assigned (n = 10/group) to a control group (C) or one of three moxa smoke concentration groups (% opacity): low (L1; 0.4% ), medium (M1; 2% ), and high (H1; 15% ). Mice in the latter three groups were exposed to moxa smoke in a dynamic gas exposure cabinet for 20 min per day for 7 days. Mice in control group were placed in the same cabinet without any intervention. For the sleep experiments, another 50 mice were divided into five groups of 10 mice each: a saline-injected control group, L1 + pentobarbital sodium (PS)-injected group, M1 + PS group, H1 (15% ) + PS group, and a positive control group (10 mg/kg, chlorpromazine, p.o.). The weight, general activities, locomotor activities, rotarod performance, sleep duration, and sleeping rate induced by a subthreshold dose of pentobarbital sodium were recorded in the mice, and the composition of moxa smoke was analyzed using headspace gas chromatography (GC-HS).

RESULTS

A low concentration of smoke significantly decreased the frequency of locomotor activities and the time for which the mice remaining on the rotarod; however, a high smoke concentration significantly prolonged the pentobarbital-induced sleeping time and sleeping rate.

CONCLUSION

The concentration-dependent relaxing effects of moxa smoke on the Central Nervous System (CNS) were confirmed. Moreover, GC-HS analysis showed that the component present in the highest concentration in moxa smoke was eucalyptol, an essential oil well recognized for its soothing effects on the CNS. This may therefore be accountable for the sedative effects of moxa smoke.