Clearing the air

We are, of course, in the midst of an air pollution crisis which, like every other threat to our health these days, is ‘worse than smoking’. According to the Royal College of Physicians, everyone in Britain is effectively smoking at least one cigarette a day, rising to many more in the most polluted cities. What’s more, as Bloomberg once put it, London has a ‘Dirty Secret: Pollution Worse than Beijing’s’. And London’s air pollution has ‘been at illegal levels since 2010’, according to the New York Times.

Serious though the problem may be — I’ll take Public Health England’s word for it that air pollution contributes to between 28,000 and 36,000 deaths per year — the hyperbole misses something important: that the air in Britain has become steadily cleaner over the past 70 years. I can still smell London as it was in the early 1970s. I remember my childhood visits and how my mother would insist on washing my hair as soon as we returned, the water in the basin turning black afterwards. And I was born a decade after the 1956 Clean Air Act, when ‘pea-souper’ smogs were already a distant memory.

But never mind anecdote — the Department for the Environment and Rural Affairs has been keeping comparable statistics since 1970. Sulphur dioxide pollution in Britain has since declined by 97 per cent. That, perhaps, is not surprising, given that the main source of it was coal-burning — something which largely disappeared after the Clean Air Acts. But progress on other forms of pollution has been pretty drastic, too. Nitrogen oxide pollution is down 72 per cent, non-methane volatile organic compounds down 66 per cent, PM10s (large diameter particles of soot and other matter) down 73 per cent and PM2.5s