American Forest and Paper Association, Inc. v. Environmental Protection Agency

In 1990, Congress amended § 112 of the Clean Air Act (CAA) to establish a list of hazardous air pollutants (HAPs), including methanol. The Environmental Protection Agency (EPA) (defendant) regulated the list of HAPs. The EPA had not, to date, established an inhalation reference concentration for methanol or an estimated maximum exposure to methanol that a human could tolerate for 70 years without experiencing any adverse health effect, as extrapolated from animal studies. The American Forest and Paper Association, Inc. (the association) (plaintiff) petitioned the EPA to delete methanol from the list of HAPs, based on a study on the effect of methanol exposure on mice (the Rogers study) and a study on the effects of methanol inhalation on primates (the Burbacher study). Based on these studies, the association proposed a “safe exposure level” (SEL) to methanol for humans of 83 mg/m3 and claimed that humans would predictably not be exposed to more than 3.65 mg/m3 in a 24-hour period, which was below the proposed SEL. The EPA disagreed with critical aspects of both studies and concluded that there was not adequate data to determine that emissions of methanol could not reasonably be anticipated to result in adverse effects on human health. The association sought review of the EPA’s denial of the petition to delist methanol, arguing that the EPA misinterpreted the statutory delisting standard and had unreasonably discounted the association’s data.