Nasal hyperreactivity among teachers in a school with a long history of moisture problems

Upper airway symptoms have frequently been reported in people working or re siding in damp buildings. However, little information has been available on objective pathophysiologic findings in relation to these environments. Twe nty-eight teachers, who had worked for at least five years in a recently re novated school that had had severe moisture problems for years, were random ly selected for this study. Eighteen teachers, who had worked in another sc hool that had no moisture problems, were randomly selected to serve as the control group. Although remedial measures had been taken, an increase in th e prevalence of mucous membrane irritations was still reported by the teach ers in the tai get school. We used a nasal challenge test with three concen trations of histamine (2, 2 and 4 mg/mL). Recordings of swelling of the nas al mucosa were made with rhinostereometry, a very accurate optical non-inva sive method. The growth curves of mucosal swelling induced by the three con centrations of histamine differed significant ly between the two groups (p < 0.01). The frequencies of atopy, evaluated with the skin-prick test, were almost identical in both groups. The study indicates that long-term exposu re to indoor environments with moisture problems may contribute to mucosal hyperreactivity of the upper airways. Such hyperreactivity also seems to pe rsist for at least one year after remedial measures have been taken.