Of the 453 requirements outlined in the 1990 update to the Clean Air Act for the EPA to fulfill, 12 were met on schedule, 202 were met late, 89 have not been met and are past due, and 150 are unmet but not yet due.
"While EPA has made progress toward implementing the air toxics program mandated by the Clean Air Act, most of the completed requirements were met late and many requirements and significant challenges remain," the report said. "As a result of EPA's limited progress, the agency has not identified and reduced health risks from air toxics to the extent and in the time frame envisioned in the act."
In February 2004, EPA completed one of four categories of requirements after the agency finished releasing 96 rules that set emission standards for 174 types of industrial facilities -- four years behind schedule. This delay has pushed back another deadline regarding an agency evaluation of the residual health risks.
In addition, EPA has completed only 16 of 70 emission standards for small stationary sources, such as dry cleaners, that accounted for one-third of air toxics emissions in 2002, according to the report.
EPA also has proposed but not finalized a standard for air toxics stemming from cars and other mobile sources of pollution.
Among other requirements not met, according to the report, EPA has failed to review and update the list of air toxics that are regulated "despite evidence that potentially harmful chemicals remain unregulated."
GAO said that the air toxics program has been a lower priority for EPA than other air quality programs that agency officials believe address more serious health risks, such as one that aims to reduce smog.
Senior EPA officials were paraphrased in the report as saying the agency's progress in implementing the air toxics program does not fully reflect efforts to reduce air toxics, which are also limited as side benefits through other air quality programs.
EPA issued a statement saying the administration "is committed to protecting public health and the environment by continuing to improve our air quality."
The statement notes that gross domestic product has increased 195 percent since 1970 while emissions have dropped 53 percent, including a 12.2 percent reduction in 2000 and a 3 percent reduction from 2003 to 2004.
The statement also said that emissions are expected to be cut by roughly 1.7 million tons annually next year, when industrial facilities are expected to comply with air toxics emission limits.
The report was requested by 11 Democrats, including House Energy and Commerce ranking member John Dingell of Michigan, as well as Senate Environment and Public Works ranking member James Jeffords, I-Vt., and Republican Sens. Lincoln Chafee of Rhode Island and Olympia Snowe of Maine.