A comparitive study between the coal-biomass briquette and raw coal in SO_2 pollution and adverse effects in rabbits

摘要

This study was conducted to evaluate the adverse health effects on rabbits exposed to SO_2 emitted indoors from burning coals, and compare differences between coal-biomass briquette (B.B.) and raw coal (R.C.). Thirty-six male rabbits were divided equally into three groups at random, and then exposed to burning R.C., B.B., and the third without burning coal (Control) for 90 days. Data showed that the average concentration of SO_2 in 24 h in R.C. was 13.04 mg m~(-3), which was 5-fold greater than B.B. (2.68 mg m~(-3)) and 31-fold higher than control (0.41 mg m~(-3)). After 45 days, the numbers of rabbits, with increased frequency of Comet cell was highest in R.C. After 90 days, the % positive Comet cell was significant at 10.36% in R.C., 5.42% in B.B., and 1.73% in Control. There was a nonlinear dose-effect relationship between % positive Comet cell and the concentration of SO_2. The incidence of interstitial pneumonia was 6/12 in R.C. and 4/12 in B.B. showing severe squamous metaplasia with atypical hyperplasia in bronchial epithelia in R.C. animals. The results of study indicate that use of B.B. reduced the emission of SO_2; but the smoke emitted from burning coal still produced DNA damage.