Dori Borrelli

February 16, 2007

On February 9, 2007 the Environmental Protection Agency (EPA) signed a final rule on the control of hazardous air pollutants from mobile sources. This rule establishes strict controls on gasoline, passenger vehicles, and gas cans to help reduce benzene and other mobile source air toxics emissions.

Mobile source air toxics (MSATs) are emitted from highway vehicles such as cars, trucks, and buses and nonroad equipment which are known or suspected to cause cancer or other serious health and environmental effects. EPA estimates that mobile sources of air toxics cause half of all cancers resulting from outdoor sources of air toxics. The agency has specifically focused on decreasing benzene levels because the compound is a known carcinogen. Furthermore, mobile sources account for the majority of benzene emissions in the United States.

The Clean Air Act amendments of 1990 mandate EPA to regulate emissions of mobile source air toxics through standards for fuels, vehicles, or both. Section 202(l)(1) of the amended Clean Air Act instructs the EPA administrator to complete a study determining the "need for, and feasibility of, controlling emissions of toxic air pollutants…associated with motor vehicles and motor vehicle fuels." Section 202(l)(2) requires the agency to promulgate regulations "based on" this study.

In March 2001 EPA published a rule under its Clean Air Act authority. This rule established toxics emissions performance standards for gasoline refiners and committed to additional rulemaking to determine whether further controls were necessary and the feasibility for such controls. Just last week, EPA finalized a rule, "Control of Hazardous Air Pollutants from Mobile Sources," which lowers emissions of benzene and other hydrocarbons such as 1,3-butadiene, formaldehyde, acetaldehyde, acrolein, and napthalene. The impact of this rule is significant: EPA estimates that by 2030 total emissions of MSATs will have dropped by 330,000 tons and volatile organic compound emissions by more than one million tons.

The rule purports to accomplish these goals in three ways: (1) by lowering benzene content in gasoline; (2) by reducing exhaust emissions from passenger vehicles operated at cold temperatures (under 75 degrees Fahrenheit); and (3) by reducing emissions that evaporate from, and permeate through, portable fuel containers. Specifically, the rule limits the benzene content of gasoline to an annual refinery average of 0.62% by volume, beginning in 2011. Additionally, the rule establishes a maximum average standard for refineries of 1.3% by volume beginning on July 1, 2012. This also functions as an "upper limit on gasoline benzene content when credits are used to meet the 0.62% standard." The hydrocarbon exhaust emissions limit will be phased in from 2010 to 2015. This rule also adopts evaporative emissions standard for passenger vehicles equivalent to those currently in force in California. Lastly, the standard for portable fuel containers (primarily gas cans) will begin in 2009.

For More Information:

Control of Hazardous Air Pollutants from Mobile Sources, EPA-HQ-OAR-2005-0036, 40 C.F.R. Parts 59, 80, 85, 86 (Feb. 2006), available at http://www.epa.gov/otaq/regs/toxics/msatfr.pdf (last visited Feb. 15, 2007).

Clean Air Act Amendments of 1990, 42 U.S.C. §§ 752(l)(1)-(2) (1990).

EPA, Air Toxics from Motor Vehicles, Environmental Fact Sheet (Aug. 1994), http://www.epa.gov/otaq/f02004.pdf (last visited Feb. 16, 2007).

EPA, Regulatory Announcement: Control of Hazardous Air Pollutants from Mobile Sources, http://www.epa.gov/otaq/regs/toxics/420f06021.htm (last visited Feb. 14, 2007).

EPA, Mobile Source Air Toxics, http://www.epa.gov/otaq/toxics.htm (last visited Feb. 14, 2007).

Felicity Barringer, E.P.A. Limits the Benzene in Gasoline by 2011, N.Y. Times, Feb. 10, 2007, available at http://www.nytimes.com/2007/02/10/washington/10benzene.html?ex=1171861200&en=57a2b2d7fa5bc96f&ei=5070 (last visited Feb. 16, 2007).