I used to live in Gdansk, and later Gdynia, and let me tell you - as soon as it's cold outside, people burn all kinds of shit at home, the air's so thick you can practically cut it with a knife. We theorized that the smog's mainly from residential burning of coal, but of course who know's what's in the stove.

All I know, is that it smells really unhealthy, and the smoke coming out of houses is a deep, black colour, almost like oil.