The economic concerns of working people are legitimate, but they will not be solved by further investments in a dying industry, which will come at a terrible cost to everyone who faces the fires, ...
Government environment measures have also helped maintain low pollution levels. Nuku'alofa, the capital of the Pacific island nation Tonga, is ranked in seventh place.
BBC Eye investigates the legacy of oil in South Sudan: from violence to pollution and asks who should be held responsible? (Image: Composite image of George Tai and oil field in the background.