"The Houston area produces about a quarter of the nation's gasoline, and about a third of the plastics that are in our cars, cupboards and just about everywhere else. So it is no surprise that this heavily industrial area has a problem with air pollution. But in the past decade, Houston's air has improved dramatically."
"How that happened is a tale of good science, new technology and a Texas law that prompted companies along the Houston Ship Channel to disclose their emissions.
The channel is a muddy brown body of water that is surrounded by refineries, tank farms and about 200 petrochemical companies. It meanders inland from Galveston Bay toward downtown.
Dana Blume is standing on the deck of a fireboat plying the channel. She's been monitoring the air and water for the Port of Houston Authority for the past 14 years."