Effect of indoor air pollution on the respiratory system of women using different fuels for cooking in an urban slum of Pondicherry

Background. Some of the highest exposures to air pollutants in developing countries occur inside homes where biofuels are used for daily cooking. Inhalation of these pollutants may cause deleterious effects on health. We studied the effects of exposure to indoor air pollution from the use of cooking fuels on lung functions and respiratory symptoms in women aged 15-60 years. Methods. The study was conducted in Kuruchikuppam, an urban slum in Pondicherry. The study participants were 105 women using biofuels, 105 using kerosene and 105 using liquid petroleum gas (LPG), selected from among 1117 women aged 15-60 years, by a stratified random sampling technique. These women were interviewed at home to collect information about exposure to fuel smoke and presence of respiratory symptoms. Lung functions were assessed by measuring forced vital capacity (FVC), forced expiratory volume in the first second (FEV(1)) and peak expiratory flow rate (PEFR). Occurrence of respiratory symptoms over six months was noted by making monthly follow up visits. Results. Women using biofuels experienced more respiratory symptoms (23%) than those using kerosene (13%; p>0.05) or LPG (8%; p<0.05). Lung functions-FVC FEV(1), FEV(1)% and PEFR-were significantly lower in biofuel users compared with both kerosene (p<0.01) and LPG users (p<0.001). Lung functions in kerosene users also were significantly poorer when compared with LPG users (p<0.01). Predicted pulmonary functions using multiple regression equations, derived from the data set of the present study, indicated that women using biofuels were more liable to have reduced pulmonary functions than women using kerosene or LPG. Conclusion. Women exposed to biofuel smoke suffer more from respiratory illnesses and have decreased pulmonary functions compared with women exposed to kerosene or LPG smoke. To reduce pollutant exposures we recommend the use of smokeless chullas or cleaner fuels such as charcoal, biogas and kerosene.