Problems, related to the occurrence of organic pollutants in the indoor environment.

Evaluation of the occurrence of organic compounds in the indoor environment is needed on at least two levels: 1. Evaluation of the overall prevalence of organic compounds in the indoor air. 2. Evaluation of abnormal concentrations in the indoor air as a result of more or less special circumstances. On both levels this evaluation can be problematic as a result of missing information on exposure to, and health risks of the measured compounds. As a result of this, only general remarks can be made about the relevance of the presence of organic compounds in the indoor air. The choice of the right policy is therefore often difficult. When, as a result of special circumstances the indoor air concentrations of organic compounds are elevated as in the case of houses built on polluted soil, or houses treated with a hydrofobing agent it is as a consequence, often difficult to take effectively the proper decisions. To solve these problems, a great deal of research appears to be necessary. By using all available information produced by the analysis and new techniques like pattern and source-recognition it may be possible to do this research in a more direct way.