In addressing the recent oil slick in the Gulf of Mexico, the US government has swung into action, mobilising the military and high-level officials for months on end. But roughly 350 miles east, the slow-motion environmental disaster above Houston continues unabated.

Because air pollution is not only invisible, but its impact on health and the environment is not immediate, it provokes little outrage; there are no images of oil-soaked birds or devastated fishermen to provoke media ire and political action.

In Houston, the energy capital of the world, there are 497 industrial facilities with a total of 27,463 flares, boilers and the like, emitting chemicals that have been linked with everything from nervous system damage to cancer. And yet environmentalists have been fighting a tough battle bringing attention to this cause.

Robert Sanborn, president of Children at Risk, a think-tank dedicated to improving the lives of Houston’s chilldren, explains:

In Texas, we do put business first. This is a good case of David and Goliath, and the state pays attention to Goliath. It’s a reality of Texas. The oil industry is the lifeblood of Houston. It’s the lifeblood of Texas industry.