The impact of information on perceived air quality: 'Organic'  vs. 'synthetic' building materials

As indoor air quality complaints cannot be explained satisfactorily and building materials can be a major source of indoor air pollution, we hypothesized that emissions from building materials perceived as unfamiliar or annoying odors may contribute to such complaints. To test this hypothesis, emissions from indoor building materials containing linseed oil (organic) and comparable synthetic (synthetic) materials were evaluated by a naı¨ve sensory panel for evaluation of odor intensity (OI) and odor acceptability (OA). The building materials were concealed in ventilated climate chambers of the CLIMPAQ type. When information was provided about the identity and type of building material during the evaluation, i.e. by labeling the materials in test chambers either as organic or synthetic, the OI was significantly lower for all the organic materials compared with evaluations without information. Similarly, OA was increased significantly for most organic  samples, but not the synthetic  ones. The major effect is probably that OA is increased when the panel is given information about the odor source.