Yesterday, the National Academy of Sciences' National Research Council (NRC) released a report citing "strong evidence" that exposure to ozone, or smog, contributes to premature mortality. According to BNA news service (subscription), "John Bailar, who led the National Research Council team, told BNA the agency is 'quite sure there is an effect, but not knowing how big it is, that's the challenge for the EPA. They have to find out the size of the problem.' " The report says that, if there is any threshold at which exposure to ozone is safe, it is likely below the level EPA recently announced as the new national air quality standard (0.075 parts per million). The NRC report should close the book once and for all on any uncertainty surrounding the link between ozone exposure and premature death. During the recent debate over the ozone standard, independent scientists, public health advocates, and EPA all recognized the potentially deadly effects of ozone and endorsed tight standards. The last remaining deniers reside mostly in the White House Office of Management and Budget (OMB). In fact, when EPA was preparing to propose its new standard for ozone, OMB edited a supporting document in order to downplay the relationship between ozone and premature mortality. The original document read, "There is considerable variability in the magnitude of the ozone-related mortality association reported in the scientific literature." OMB altered the language to, "There is considerable uncertainty in the magnitude of the association between ozone and premature mortality." [Emphasis added.] The nonprofit group Environmental Defense came up with another example of OMB interference. In a rulemaking that would limit emissions from small engines, OMB objected to EPA's assertion that ozone is related to premature death: The EPA response to OMB's objection states: "We have removed all references to quantified ozone benefits (including mortality) in the most recent version of the [economic impact statement]." The EPA document in question was, in fact, finalized with the monetized benefits of reducing ozone removed. Meanwhile, EPA has yet to finalize the clean air standards for these high-polluting engines. The NRC report says that policy makers "should give little or no weight" to arguments like the one advanced by OMB.