Adverse effects of smoke exposure on the upper airway

This paper reviews secondhand smoke (SHS) exposure and diseases and symptoms of the upper airway, including the sinuses. Risks to flight attendants, who were occupationally exposed until smoking was banned on all flights, are emphasised.

A systematic database search was conducted; the US Surgeon General's reports and other major reviews were evaluated. Literature summarised by National Research Council (NRC) reports on the airline cabin environment are included.

A limited number of research publications on adults were identified; these are included. Many studies cited by the NRC were never published and information is taken directly from the reports.

Data from observational studies of cabin crews and the general public were extracted from surveys; exposure monitoring of cabin crews is reported. Data from controlled exposure studies are included; most are challenge studies using volunteers screened for sensitivity to SHS.

Evidence shows that active and passive smoking cause upper airway diseases, including sinonasal and laryngeal cancers in adult active smokers. Experimental studies indicate that brief exposures to SHS result in nasal mucosa inflammation. However, direct evidence on sinusitis is limited.

Evidence does not show a strong connection between active smoking and sinusitis, and active smokers have substantial exposures to SHS. However, extrapolation of these studies to cabin crews needs to be cautious, as other environmental conditions may increase risk for upper airway disease and symptoms. Surveys of cabin crews, while flawed, consistently indicate high rates of upper airway symptoms.