Last week, the EPA Clean Air Science Advisory Committee provided EPA its review of EPA’s Policy Assessment for the Reconsideration of the National Ambient Air Quality Standard for ozone. As expected, CASAC has disagreed with the recommendation of EPA technical staff to retain the current 70 ppb standard. Instead, CASAC recommends a significantly lower ozone NAAQS of 55-60 ppb.
This seems to be coming down to a fight between EPA’s reliance on controlled human exposure (CHE) studies and CASAC’s position that EPA is giving too little weight to epidemiological studies,… More