Complaints about discomfort and effects on health are commonly reported from homes, workplaces, schools and daycare centres in various countries. Despite difficulties in relating these problems to specific agents in the indoor environment, it is often possible in practice to initiate efficient remedial actions by using a strategy involving structured information from the occupants and various technical measurements. In this presentation, a practical approach to indoor air problems is discussed, based mainly on experience from studies using the standardized MM questionnaires. By using suitable reference values, one can deal with the complex situation arising from multiple low‐level exposures of physical and biological origin, psychosocial and socioeconomic factors and variations in susceptibility of the occupants.

The administration of drugs together suggests an inhibition of debrisoquin metabolism caused by the concurrent drugs given. By separating debrisoquin from the other cocktail drugs, this method is likely to be used as a tool to phenotype the enzymes CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 with only 2 urinary collections and 2 blood-sampling occasions.