Abstract
A questionnaire study among 70 employees at seven mobile day care centers where urea formaldehyde glued particle board has been used for indoor paneling and among 34 employees at three control institutions selected at random where no particle board has been used as building materials, showed a significantly higher frequency of the following symptoms among the staff at the mobile institutions: mucous membrane irritation, headache, abnormal tiredness, menstrual irregularities and use of analgetics (p<0.01). As there was no difference in the age distribution or smoking habits of the two groups working in day care institutions from the same geographical location, we are, therefore, of the opinion that the differences in the frequency of symptoms discovered must be attributed to the differences in the indoor climate conditions prevalent in the institutions. The median concentration of formaldehyde in the mobile institutions was 0.43 mg/m3 in contrast to a concentration in the control institutions of about 0.08 mg/m3. We assume, therefore, that the higher concentration of formaldehyde in the mobile institutions was a cause of the increased frequency of symptoms among the staff. The National Health Service should be aware of the fact that non-specific symptoms such as headache and abnormal tiredness can be the result of unfavorable indoor climate conditions due to the presence of formaldehyde in building materials.