In vitro exposure of human lung cells to emissions of several indoor air sources created in a climate chamber

In the last decade, studies on indoor air pollution suggest a link between exposure to indoor particulate matter and compounds, in particular ultrafine particles and secondary organic aerosols, and several health effects. The mechanisms of how those complex mixtures relate to health effects are still not fully understood. In vitro testing, i.e., performing a given procedure in a controlled environment outside of a living organism, provides an additional source of information next to the exposure of persons or animals to controlled environmental conditions in a laboratory environment. Possible end-points that can be determined with such a system are oxidative stress, inflammation and cell-death. The applicability of an in vitro system with human lung cells as an instrument to evaluate possible biological effects of emissions of several indoor air sources (scented candles, hair and water resistant spray) created in a climate chamber was studied. Results demonstrate that the procedure for testing the emissions of scented candles and two sprays resulted in reproducible test conditions and reproducible toxicological results. In vitro testing seems to have potential as a means to get more and better understanding of the mechanisms and causes for health effects of 'real-life' complex mixtures caused by sources such as burning candles and using spray cans. More tests with different indicators and endpoints, different concentrations and exposure time are required