The US Environmental Protection Agency (EPA) issued the
Mobile Source Toxics (MSAT) Rule on February 26, 2007 (40
CFR Parts 59, 80, 85 and 86). This rule required refiners
to reduce the average benzene concentration in the gasoline
pool to 0.62 vol% or less by January 1, 2011. Refiners
producing higher levels could reduce their concentration by
purchasing credits, but they are capped at a maximum actual
average concentration of 1.3 vol%.