Does a mask protect cyclist against fumes?
Q - I have seen cyclists in urban areas wearing face masks, presumably fitted with filters to reduce the amount of pollutants they inhale. Is there any benefit to these masks? Will these filters become less effective or bacteria-laden with continued use?
A - The general view of experts in this field is that healthy people are not at risk from air pollution and that respiratory protection is therefore not necessary. The sort of masks that one can buy are of varying effectiveness against particles, and the Consumers Association brought out an issue of Which? on this about five years ago.
Nobody yet knows whether any of these masks filter out the ultra-fine particles that some believe harm the vulnerable and none of them is effective against pollution gases.
All filters become less effective the longer they are used, and manufacturers give advice on useful life. My view is that masks are unnecessary, although wearing them makes a visible point to other road users about pollution. I personally do not wear one when I cycle into the city.
Incidentally, it would be more logical to wear them inside cars, since the people in them are more likely to be unfit and pollutants become concentrated inside vehicles!
Anthony Seaton is professor of occupational and environmental medicine, University of Aberdeen