HOUSTON -- Several Houston-area plants will be forced to pay millions of dollars for polluting the air, officials told KPRC Local 2.

The Texas Attorney General announced the fines against seven Texas plants, including five in the Houston area.

Seven Lyondell subsidiary plants were alleged in 2005 to have allowed chronic or long-term releases of hazardous chemicals.

"There will be a price to pay if someone doesn't comply with the environmental law," Texas Attorney General Greg Abbott said.

That price is approximately $6.5 million. It's what Lyondell agreed to pay to settle a suit brought by the attorney general.

Five of the plants are located near Houston -- in Channelview, La Porte, Pasadena and just outside Alvin.

State inspectors alleged the plants released a variety of harmful chemicals, including nitrogen oxides, carbon monoxide, and organic compounds.

Some of the violations date back to 2003.

"I think actions like this will ensure everyone will work toward compliance," Abbott said.

But it's not happening soon enough for clean air watchdogs. Houston has some of the dirtiest air in the country and has for decades, industry experts say.

Critics complained the Texas commission on Environmental Quality is moving too slowly with too few resources to police pollution.

"It's now August 2008 and we finally have a penalty in place and we're finally starting to re-mediate these emissions, that's just not acceptable. People are breathing this stuff. It's creating ozone for the entire region. We've been in non-attainment for ozone for 30 some-odd years now. This cannot be taking this long," said Matthew Tejada, with the Galveston-Houston Association for Smog Prevention.

Houston Mayor Bill White issued a statement saying he supports the settlement hammered out by the attorney general.

He said the violations tallied against those Lyondell plants points to the need for real-time monitoring of emissions at all of the areas petrochemical plants.