Interesting thing on the news this morning about Heathrow. Apparently the pollution levels around the airport are actually generated primarily by vehicles and not aircraft as most anti runway campaigners suggest.
So plans to reduce London pollution levels by introducing less polluting vehicles could have a knock on affect by lowering pollution around the airport to keep a new runway within pollution laws, which it wouldn't currently meet.
Sounds like good news, unless of course you live around Heathrow, in which case it's no doubt bad news