Impact of Exposure to Biomass Fuel on Pulmonary Function and Lung Age in Rural Women

Abstract

BACKGROUND Around half a million of people still rely on biomass fuels for cooking, which is a major source of household air pollution, associated with increased morbidity and mortality. Biomass smoke exposure is associated with airway obstruction and decreased ventilatory function. Though various studies are available in relation to biomass exposure and pulmonary function, literature is limited on lung age. Hence, the current study was undertaken to evaluate the effect of biomass fuel on pulmonary function and lung age in rural women and correlate biomass exposure index with the spirometry parameters and lung age. METHODS A cross sectional study was conducted in rural areas of Tamilnadu. Around 350 women were screened and 100 women aged > 18 years with biomass exposure for at least five years and able to perform spirometry were selected for inclusion in the study. After obtaining consent, the subjects were evaluated further with detailed history and spirometry to record the lung function parameters and lung age. Biomass exposure index was calculated from hours spent in cooking per day multiplied with the years of cooking. RESULTS Mean age of the participants was 49.88 ± 10.76 years. 68 % had indoor kitchen with inadequate ventilation in 57 % of households. Majority of the women were housewives and belonged to the middle- and low-income groups. Around 19 % were symptomatic with cough and expectoration being predominant symptoms. Spirometry was abnormal in 83 % of the women and showed obstruction in majority. Mean forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), forced expiratory flow 25 - 75 % (FEF) and peak expiratory flow (PEF) were reduced in the study population. A significant negative correlation was observed between the biomass exposure index (BEI) hour-years and FEV 1 and FEF 25 % - 75 %. A significant positive correlation was observed between BEI hours-year and lung age. CONCLUSIONS Majority of the women exposed to biomass fuel smoke, though asymptomatic, had abnormal lung function with increased lung age. Intensity of exposure as measured by biomass exposure index correlated significantly with FEV1, FEF 25 - 75 % and lung age. Hence, regular surveillance of the women using biomass fuel for cooking should be done for early identification of respiratory impairment. KEY WORDS Biomass Exposure, Biomass Fuel, Pulmonary Function, Lung Age, Biomass Exposure Index