London is reported to be the worst polluted part of the UK.
Surprisingly York has terrible air quality. Its a quirk of geography basically the air just gets trapped over it. You can see the haze from the top of Whitwell somedays. Luckily here up on the Wolds we don't have that problem, mind you the rape can get a bit overpowering sometimes.
It shouldn't be too much of a surprise given its location downwind (the prevailing wind) of cities like Leeds and Sheffield, to say nothing of the power stations to the south.
When I moved to York from Suffolk in an autumn the early 1990s I went house-hunting on my bike. There was a prolonged period of high pressure and freezing fogs and I got a very bad chest as a result. There has been nothing quite as severe since fortunately.
Driving to the Limousin on the 9th April I was amazed at the deterioration in air quality as I went south. From the Dartford Bridge, mid-day, the waters of the Thames were hidden under a layer of fog. The ferry I boarded at Dover had to keep the foghorn going until about half-way across La Manche.
