Petcoke (green petroleum coke) is a by-product from refining heavy oils. It is cheaper and burns hotter than coal. Petcoke also contains more heart- and lung-damaging sulfur and planet-warming carbon.
The US is the world's largest producer and exporter of petcoke as the country's oil refineries are unable to sell the toxic waste product at home.
In Paraíba, Brazil, the main users of petcoke are the cement factories. Local residents exposed to the powder stored near their houses suffer from abnormalities in their lung functions.