ELR Citation: ELR 20140
No(s). 09-1011 (D.C. Cir. May 14, 2010)

The D.C. Circuit denied a petition for review challenging EPA's revision of air quality criteria and NAAQS for lead. The revision was designed to provide, in light of recent science, the requisite protection of public health and welfare by revising the permissible level of lead in ambient air and revising the averaging time over which the level must be met. The final rule also revised data handling procedures and emissions inventory reporting requirements and provided guidance on implementation. The court rejected petitioners' arguments that the revision was arbitrary and capricious. Petitioners' assertion that the revised lead NAAQS is overprotective because it is more stringent than necessary to protect the entire population of young U.S. children ignores that the CAA allows protection of sensitive subpopulations. Given the recent scientific evidence on which it relied, EPA's decision to base the revised lead NAAQS on protecting a subset of children likely to be exposed to airborne lead at the level of the standard was not arbitrary and capricious. EPA's selection of scientific studies was also reasonable. The Agency adequately justified its decision to rely on analyses of IQ in children with blood lead levels closest to those of today's population of children when revising the lead NAAQS. Petitioners also failed to show that EPA's conclusions regarding the lead NAAQS were valid only for exposures to lead averaged over a one-year period.