Lennart Bodin

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 residing in damp buildings. However, little information has been available on objective pathophysiologic findings in relation to these environments. Twenty-eight teachers, who had worked for at least five years in a recently renovated school that had had severe moisture problems for years, were randomly selected for this study. Eighteen teachers, who had worked in another school that had no moisture problems, were randomly selected to serve as the control group. Although remedial measures had been taken, an increase in the prevalence of mucous membrane irritations was still reported by the teachers in the target school. We used a nasal challenge test with three concentrations of histamine (1, 2 and 4 mg/mL). Recordings of swelling of the nasal mucosa were made with rhinostereometry, a very accurate optical non-invasive method. The growth curves of mucosal swelling induced by the three concentrations of histamine differed significantly 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 exposure to indoor environments with moisture problems may contribute to mucosal hyperreactivity of the upper airways. Such hyperreactivity also seems to persist for at least one year after remedial measures have been taken.

Effects on human eyes caused by experimental exposures to office dust with and without addition of aldehydes or glucan

UNLABELLEDnThirty-six volunteers (in three susceptibility groups: 11 subjects were non-allergic with nasal histamine hypersensitivity, 13 were non-allergic with normal sensitivity, and 12 were pollen allergic with or without nasal hypersensitivity) were exposed for three and a half hours in a climate chamber. Each subject was exposed to clean air (dust 45 +/- 38 microg/m(3) total suspended particle, TSP), house dust at 357 +/- 180 microg/m(3) TSP, house dust 382 +/- 175 microg/m(3) TSP with added glucan (50 ng/m(3)) and house dust 394 +/- 168 microg/m(3) TSP with added aldehydes corresponding to a gaseous phase of 300 microg/m(3) in the air. The study was explorative by nature. No significant effects of exposures as such were seen on break-up time, conjunctival epithelial damage score and Trolox Equivalent Antioxidant Capacity (TEAC) in tear film and subjective ratings. However, in TEAC a significant different time course was seen during exposures to aldehyde-containing dust indicating a subacute and late response to the exposures. Perceived eye irritation increased significantly during exposures to normal dust. The perception ratings were highly correlated, whereas no correlation was found between the subjective responses and the objective measurements.nnnPRACTICAL IMPLICATIONSnThe findings indicate that measurement effects on the eyes are rather insensitive measures of short time effects of office dust exposures.

Nasal mucosal histamine reactivity among young students and teachers, having no or prolonged exposure to a deteriorated indoor climate.

Background: In a study performed in the spring of 1995, we found a significantly greater nasal mucosal histamine reactivity among teachers, who had worked for several years in a recently renovated moisture‐damaged school, than in those in a control school. In the present study we investigated the students who begun their high‐school studies at both schools in the autumn of 1995 and compared them with the teachers as regards mucosal reactivity, atopy and symptoms.