Volatile organic compounds (VOCs) such as benzene and toluene, and low molecular weight carbonyls like formaldehyde belong to the main air pollutants found in indoor environments. They are suspected to induce acute and chronic adverse health effects like asthma, allergic and cardiovascular diseases, and strongly affect well-being. Our aim was to further develop and optimize an in vitro method to study the exposure of epithelial tumour lung cells (A549) by using a commercial exposure chamber (CULTEX) to assess the biological effects of VOCs and carbonyl compounds at low concentration levels. Exposing the cells to toluene, benzene and formaldehyde at mixing ratios varying from 0.1 to 0.6ppmv in air resulted in reproducible direct effects with the induction of an inflammatory response and a modification of the glutathione redox status.