Changes of symptoms, tear film stability and eosinophilic cationic protein in nasal lavage fluid after re-exposure to a damp office building with a history of flooding.

UNLABELLED: The aim was to study health effects in office workers (N = 18) in a medical case book archive with dampness caused by flooding. They were first investigated in a building without dampness (exposure free for 10 days). Then all returned to the damp building, and were re-investigated after 2 days. We measured tear film break up time (BUT), nasal patency, biomarkers in nasal lavage (NAL), and dynamic spirometry. Both buildings had low CO(2) (380-600 ppm), low levels of respirable particles (8-10 microg/m(3)), and formaldehyde (5-7 microg/m(3)). The flooded building had slightly higher (149 ng/m(3) vs. 94 ng/m(3)) levels of microbial volatile organic compounds (MVOC). After 2 days of re-exposure, there was an increase of ocular (P < 0.001), nasal (P = 0.002), and throat symptoms (P < 0.001), dyspnea (P = 0.006), headache (P = 0.002), nausea (P = 0.04), and tiredness (P = 0.01). The median BUT decreased from 16 to 8 s (P = 0.003), and eosinophilic cationic protein (ECP) in NAL increased slightly (P = 0.04). A separate test of the weekday effect showed slight improvements, or no change of symptoms and signs from Monday to Wednesday. In conclusion, subjects previously exposed to building dampness had an increase of symptoms, reduced tear film stability, and signs of eosinophilic inflammation in the nasal mucosa after 2 days of re-exposure. PRACTICAL IMPLICATIONS: The study is in agreement with previous cross-sectional studies, suggesting that building dampness may cause mucosal irritation, general symptoms such as headache and tiredness, impaired tear film stability, and eosinophilic inflammation in the airway mucosa. From a preventive point of view, health consequences of water leakage and flooding should not be neglected. The measurements of molds and microbial volatile organic compounds could not identify any obvious exposure contrast between the damp building and the dry control building. This illustrates the limitations of air measurements of microbial exposures in damp buildings.