Long-term exposure to incense smoke alters metabolism in Wistar albino rats

The burning of incense is an important source of indoor air pollution in Asia. We assessed the effect of long-term exposure to incense smoke on the body weight and levels of circulating glucose, triglycerides, total cholesterol, HDL-cholesterol, insulin, adiponectin and leptin in Wistar albino rats. Two groups of rats were used. First group (n = 12) was exposed daily to incense smoke for 4 months at the rate of 4 g day(-1) in the exposure chamber. Another group of rats (n = 12), was used as non-exposed control. Blood samples were collected from all animals after 4, 8, 12 and 16 weeks of exposure. Serum glucose, triglycerides, total cholesterol and HDL-cholesterol, LDL-cholesterol insulin, adiponectin and leptin were measured. Our results showed that incense smoke exposure was associated with decreased weight gain and the adverse metabolic changes of increased triglycerides and decreased HDL-cholesterol concentrations. Exposure to incense was also associated with a transient increase of leptin levels. Taken together, these data suggest that incense smoke influences metabolism adversely in rats. The effect of incense smoke on human health and the underlying mechanisms need to be studied further.