But the government is becoming increasingly concerned about the problems that pollution brings, such as sickness from filthy air and arid soil from acid rain, which has made it keen to boost the use of renewables and increase energy efficiency.

ECONOMIST: Anti-hero

Oliver Twist also highlights the rank poverty of the inner cities - particularly when the plot moves to Jacob's Island, " the filthiest, the strangest, the most extraordinary of the many localities that are hidden in London " where the houses were "so filthy, so confined, that the air would seem to be too tainted even for the dirt and squalor".

BBC: News Magazine

And I had the opportunity to go up in the air and see it a few times, and just filthy floodwater, because floodwater is filthy, as far as the eye could see.

WHITEHOUSE: President Obama & Prime Minister Gillard Visit Wakefield High School | The White House