"Aircraft manufacturers design their aircraft to meet the regulatory standards, including those for cabin air, and airlines operate the aircraft in accordance with the manufacturer's instructions.
Studies of cabin air quality have consistently shown that the cabin air on commercial aircraft meets all regulatory standards and is as good as or better than that of typical offices or homes. There is no evidence to suggest that crew or passengers are exposed to levels of contaminants that could be harmful to health.
Incidents of smoke or fumes do occur occasionally as a result of minor malfunctions, such as electrical faults or oil leaks. Flight and cabin crew are trained in the procedures to follow in such events, as recommended by the regulatory authorities to all airlines. Research into such incidents carried out by and on behalf of the CAA has found no evidence that exposure to fumes in these circumstances has any persisting health effects."