London has dangerously high levels of the noxious pollutant nitrogen dioxide in its air, even higher than the notoriously smoggy Beijing. Surprisingly, the lion’s share of the blame for these rising levels can be placed not on old clunkers but on fleets of new cars that run on diesel.
Diesel gets better mileage than gasoline, which has led countries across Europe to promote diesel-fueled cars as a way to meet lower EU-wide CO2 requirements. That may have helped reduce that particular greenhouse gas, but has also worsened air pollution in cities like London. Bloomberg reports:
“Successive governments knew more than 10 years ago that diesel was producing all these harmful pollutants, but they myopically plowed on with their CO2 agenda,” said Simon Birkett, founder of Clean Air in London, a nonprofit group. “It’s been a catastrophe for air pollution, and that’s not too strong a word. It’s a public-health catastrophe.”
Tiny particles called PM2.5s probably killed 3,389 people in London in 2010, the government agency Public Health England said in April. Like nitrogen dioxide, or NO2, they come from diesel combustion. Because the pollutants are found together, it’s hard to identify deaths attributable only to NO2, said Jeremy Langrish, a clinical lecturer in cardiology at the University of Edinburgh.
This is a thorny issue, and there are many trade-offs to mull over in crafting these kinds of policies. Ideally, every driver would drive electric, emission-free cars powered by consistent renewable energy, but we don’t live in that world. Electric car technology is getting better (Elon Musk’s work with Tesla has been remarkable), but for now that green dream remains a fantasy.