BRONCHIAL RESPONSIVENESS OF NONSMOKING WOMEN EXPOSED TO ENVIRONMENTALTOBACCO-SMOKE OR BIOMASS FUEL COMBUSTION

We studied bronchial responsiveness (BR) in three groups of housewives with or without history of exposure to tobacco smoke or combustion of biomass fuels. Methacholine bronchoprovocation test was used to study BP. The group I subjects (60), who served as controls, were nonsmoker s and had no chronic exposure to passive smoking or environmental toba cco smoke (ETS) or biomass fuels. Three of these women showed a 20 per cent FEV(1) fall with a cumulative methacholine dose of 72.5 mg or le ss. Of 60 women in group II GETS-exposure) and 52 in group III (biomas s exposure), 26 (43.3%) and 10 (19.2%) respectively showed bronchial h yper-responsiveness (BHR). The odds ratios for BHR in groups II and II I were 14.53 and 4.52 respectively. The number of hyper-responders was significantly more and the mean PD20 less in the exposed than the non -exposed groups. The occurrence of BHR in the ETS exposed group was mo re (P < 0.05) than the biomass combustion group. There were more hyper -responders (both groups LI and III) amongst those who had an exposure index (EI) of 50 or more compared to those with EI of less than 50. W e conclude that chronic cumulative exposure to both ETS and biomass cu mbustion produces significant BHR. Further, BHR developed more often o n ETS exposure, and when the exposure was present for a longer period.