London has a dirty secret.
Levels of the harmful air pollutant nitrogen dioxide at a city-center monitoring station are the highest in Europe. Concentrations are greater even than in Beijing, where expatriates have dubbed the city’s smog the “airpocalypse.”
It’s the law of unintended consequences at work. European Union efforts to fightclimate change favored diesel fuel over gasoline because it emits less carbon dioxide, or CO2. However, diesel’s contaminants have swamped benefits from measures that include a toll drivers pay to enter central London, a thriving bike-hire program and growing public-transport network.
An unintended consequence of EU membership?