Tag Archives: “Evaluating the impact of long-term exposure to fine particulate matter on mortality among the elderly”

Will Evidence of Causality Be Enough to Change EPA’s Mind About the PM2.5 Standard?

There have been numerous studies that support a decrease in the current PM2.5 annual standard of 12 ug/m3.  EPA has nonetheless proposed to retain the current standard on the basis that there is too much uncertainty regarding whether those studies provide a basis for concluding that PM2.5 concentrations below the standard cause increased mortality.  As I have previously noted, the statutory provision requires that NAAQS be set with an “adequate margin of safety.”  That would seem to require EPA to resolve such uncertainty in favor of a more stringent standard.… More