Background: The adverse health effects of biomass fuel exposure (BFE) is complex and widespread. According to our knowledge, the interstitial lung disease due to BFE is not clear in literature. Objective: In this descriptive crossectional study, the main objective was to assess the effects of BFE on the respiratory system. Methods: Patient group was included non-smoker 21 woman and the control group was included non-smoker 22 woman. High resolution computed tomographic (HRCT) examinations were made with supin and prone positions in two groups. The spirometric measurements, including the diffusion capacity at rest for carbon monoxide, single breath (DLCO), were also made. Results: It was found that BFE caused obstructive and restrictive spirometric impairments. The prevalence of the fibrotic bands, peribronchovascular thickenings, nodular radio opacities, and curvilinear densities in the high resolution computed tomographic examinations were 7, 5, 7, and 16 times higher in the exposure group than the control group, respectively. There was a significant positive correlation between the forced vital capacity (FVC), forced expiratory volume first second (FEV1), FEV1/FVC, forced expiratory flow during middle half of forced vital capacity (FEF25-75), DLCO and the volumetric densities of the HRCT slices with deep expiration in prone position. Conclusions: We think that, the findings due to BFE, pose a special situation and it can be named "biomass lung". (C) 2004 Elsevier Ireland Ltd. All rights reserved.