Objective assessment of ocular and respiratory alterations in employees in a sick building

Sick building syndrome (SBS) is a constellation of diffuse, "irritative" symptoms predominantly involving the eyes and the respiratory tract. To date, the effects of working in a "sick building" have not been adequately assessed using objective measures. We undertook the present study to determine whether objective alterations could be found in the eyes and respiratory' tracts of employees working in an office building in which a high rate of SBS had been reported in the preceding year.

We studied 163 office workers: 87 workers from a modern, air-conditioned building (the sick building), and 76 employees employed in three traditional-style office buildings (the comparison buildings). After being surveyed for SBS symptoms, all subjects underwent a series of objective tests, including spirometry, a methacholine test, prick tests for aeroallergens, and submitted tear samples. In addition, Schirmer's test and the break-up time test were used to explore for potential ocular effects of sick building exposure.

Employees in the sick building complained more frequently of ocular symptoms, upper-airway disturbances, and general and respiratory' symptoms than did employees in the comparison buildings; prick tests were positive in 20% and 17.4%, respectively. Groups did not differ significantly on spirometry measures. Bronchial hyperreactivity to methacholine (PD15 = 16.348 mumol) was present in 20.5% of the sick building workers and in 16.2% of comparison buildings workers. Methacholine dose-response slope values were similar. Stability of tear film was significantly reduced (P < 0.01) in the employees in the sick building compared with employees in the comparison buildings.

Our results indicate that (1) atopy does not seem to influence the prevalence of SBS symptoms, and (2) the lower respiratory tract seems unaffected by exposure to a "sick building," but (3) alterations in tear film stability do exist after such exposure.