Respiratory health among office workers in Malaysia and endotoxin and (1,3)-β-glucan in office dust

<jats:p><jats:bold>OBJECTIVE:</jats:bold> To examine the associations between endotoxin and (1,3)-β-glucan concentrations in office dust and respiratory symptoms and airway inflammation among 695 office workers in Malaysia.<jats:bold>METHODS:</jats:bold> Health data were collected using a questionnaire, sensitisation
testing and measurement of fractional exhaled nitric oxide (FeNO). Indoor temperature, relative air humidity (RH) and carbon dioxide (CO<jats:sub>2</jats:sub>) were measured in the offices and settled dust was vacuumed and analysed for endotoxin and (1,3)-β-glucan concentrations. Associations were
analysed by two level multiple logistic regression.<jats:bold>RESULTS:</jats:bold> Overall, 9.6% of the workers had doctor-diagnosed asthma, 15.5% had wheeze, 18.4% had daytime attacks of breathlessness and 25.8% had elevated FeNO (≥25 ppb). The median levels in office dust were 11.3 EU/mg endotoxin
and 62.9 ng/g (1,3)-β-glucan. After adjusting for personal and home environment factors, endotoxin concentration in dust was associated with wheeze (<jats:italic>P</jats:italic> = 0.02) and rhinoconjunctivitis (<jats:italic>P</jats:italic> = 0.007). The amount of surface dust (<jats:italic>P</jats:italic> = 0.04) and (1,3)-β-glucan concentration
dust (<jats:italic>P</jats:italic> = 0.03) were associated with elevated FeNO.<jats:bold>CONCLUSION:</jats:bold> Endotoxin in office dust could be a risk factor for wheeze and rhinoconjunctivitis among office workers in mechanically ventilated offices in a tropical country. The amount of dust and (1,3)-β-glucan (a marker
of indoor mould exposure) were associated with Th2 driven airway inflammation.</jats:p>