In an unprecedented action, the Environmental Protection Agency's own scientific panel on Friday challenged the agency's proposed public health standards governing soot and dust.
The Clean Air Scientific Advisory Committee, mandated by Congress to review such proposals, asserted Friday that the standards put forward by EPA Administrator Stephen L. Johnson ignored most of the committee's earlier recommendations and could lead to additional heart attacks, lung cancer and respiratory ailments.
The Los Angeles Basin, especially the Riverside area, and the Owens Valley in the Eastern Sierra have the worst particulate pollution in the nation. The problem in urban areas is largely attributable to truck exhaust and diesel-powered vehicles; the Owens Valley has major dust storms.
In December, Johnson proposed to slightly tighten the health standards that state and local governments must meet in regulating industries and other sources of pollution. But those standards, governing the smallest and most hazardous particles of soot, were substantially weaker than the scientists' recommendations.
Johnson also proposed to exempt rural areas and mining and agriculture industries from standards governing larger coarse particles, and he declined to adopt the panel's proposed haze reduction standards.
EPA officials are taking public comment on the proposed rules through April and plan to meet a court deadline to adopt final standards by September.
Some panel members called the administrator's actions "egregious" and said his proposals "twisted" or "misrepresented" their recommendations.
"We are obligated to recommend something beneficial to public health," said the panel's longest-serving member, Morton Lippmann, a professor of environmental medicine at New York University School of Medicine.
After a teleconference Friday lasting nearly four hours, the committee members decided to write a letter to Johnson laying out the scientific evidence for their conclusions and urging him to reconsider his proposals.
It was the first time since the committee was established under the Clean Air Act nearly 30 years ago that the committee had asked the EPA to change course, according to EPA staffers and committee members.
"We're in uncharted waters here," acknowledged committee Chairwoman Rogene Henderson, an inhalation toxicologist. She said their action was necessary because "the response of the administrator is unprecedented in that he did not take our advice. It's most unusual for him not to take the advice of his own science advisory body."
Several members said Johnson's proposals incorrectly said the committee had called for eliminating the regulation of coarse particulates for mining and agriculture.
Those exemptions have been lambasted by state and regional air regulators across the nation, including officials from the Owens Valley and elsewhere in California.
Panel member Richard Poirot, an environmental analyst with Vermont's Air Pollution Control Division, said the proposed exemptions were being wrongly attributed to committee recommendations.
In a more conciliatory tone, many members also said that as part of their earlier recommendations they should have communicated more clearly the reasons for their views, praised EPA staffers' hard work and acknowledged that Johnson as the policymaker had the final say.
Johnson was not available for comment Friday. But acting EPA air chief William Wehrum said: "We greatly respect the input CASAC has given us so far. If they choose to give us further input we will ... certainly consider it carefully as we move forward to make any final decision."
He said that the EPA had made "every effort" to explain why it did not follow all of the panel's findings and that it was seeking broad comment on the panel's recommendations as well as the proposed rules.
"The science behind particulate matter is extremely complex, and there's a lot of it out there. We know there's a diversity of opinion," he said.
The California Environmental Protection Agency, the California Air Resources Board, other air-quality regulators and environmentalists have denounced the EPA particulate proposals.
Cal/EPA's air pollution epidemiology chief, Bart Ostro, charged during the teleconference that the EPA had incorporated "last-minute opinions and edits" by the White House Office of Management and Budget that "circumvented the entire peer review process."
He said research that he and others had conducted also had been misrepresented in the EPA's lengthy justification for the proposed new standards.
In an interview later, Ostro said he was referring to marked-up drafts of Johnson's proposals that showed changes by the White House budget office and language that was "very close to some of the letters written by some of the trade associations."