The National Resources Defense Council (NRDC) says EPA Administrator Scott Pruitt has missed the statutory deadline to report to the American people which U.S. counties exceed the national health standard for ground-level ozone, or smog.

On Oct. 1, 2015, EPA strengthened its smog standard, reducing the acceptable limit from 75 parts per billion to 70 ppb to better protect Americans, especially children, senior citizens and anyone who works or exercises outdoors, from the harmful effects of smog pollution. The Clean Air Act gives the agency two years to announce which areas of the country have unsafe smog levels of 70 ppb or higher.

“Mr. Pruitt is showing a blatant disregard for the law by refusing to give Americans a full accounting of how much unsafe smog they’re breathing," said John Walke, director of NRDC’s Clean Air Project.

Walke said the failure is irresponsible and illegal. “It risks the health of millions of people and stalls required cleanup steps. And it’s why we’ll continue to use every tool available to make sure all Americans learn sooner rather than later whether their air is dirty and endangering their health.”

An EPA analysis shows that the more protective limit is expected to prevent 230,000 asthma attacks among children, 160,000 days when dirty air keeps kids home from school, 630 asthma-related emergency room visits, 340 cases of acute bronchitis among children and 320 to 660 premature deaths, outside of California.

The NRDC says the safeguard can only protect people's health if the EPA tells the whole truth about which areas of the country don’t comply.

“States can’t meet their legal obligation to devise plans to reduce smog to safe levels if they don't know everywhere the problem exists,” said Walke. “If we have to take Pruitt back to court to protect the health of millions of Americans, NRDC stands ready to do so again.”