Leaded Gas Phaseout
Leaded Gas Phaseout
Air Quality Fact Sheet
Leaded gasoline will no longer be available in the United States after December 31, 1995.
The Clean Air Act Amendments of 1990 mandate the elimination of lead from all U.S. motor fuel by January 1, 1996. This
represents the final step in a gradual reduction of lead in gasoline since the early 1970s. "Regular" gasoline typically
contained approximately 4.0 grams of lead per gallon; average lead content was reduced to 0.5 gram/gallon in 1985, and
still further to 0.1 gram/gallon in 1986.
"Unleaded gasoline" is allowed to contain no more than 5/100ths of a gram of lead per gallon.
Why remove lead from gasoline?
Lead is extremely toxic. Studies show that exposure to high concentrations of lead, particularly in young children, can result
in damage to the central nervous system, and may be associated with high blood pressure in adults. Human exposure to lead
typically occurs via inhalation of air and ingestion of lead in food, soil, water or dust.
Airborne lead concentrations throughout the country have decreased 89 percent since 1984, directly due to the phaseout of
leaded gasoline, as well as to the majority of cars equipped with pollution control devices that require using unleaded fuel.
How will unleaded gasoline affect my older car's performance?
A basic rule of thumb for refueling a pre-1971 vehicle is to use unleaded gasoline with the same octane rating as the
previously-used leaded gas. Under normal driving conditions, the use of unleaded fuel should not cause any problems with
the vehicle's performance.
Pre-1971 engines were equipped with "soft" valve seats and leaded gasoline acted as a lubricant to prevent excessive wear
of the valve seats. Using these engines with unleaded fuel in high-speed/high-load situations could result in some valve seat
wear. (Boats, some farm equipment, and tow vehicles may be included in this category.) Substitute lubricant additives are
available at auto supply stores to help this situation. In addition, valve seats are usually replaced with at the time an older
engine is rebuilt. If you are concerned about your particular application, check with your engine manufacturer.
Does this mean my engine will wear out sooner without the protection of lead?
No. In fact, unleaded fuel can help extend maintenance intervals. In the past, lead deposits on spark plugs were the main
reason to change them so often. Today's cars are built with pollution control equipment that is specifically designed to run on
For additional information on the phaseout of leaded gasoline, contact your engine manufacturer, or call the Environmental
Protection Agency, Region 10 at (206) 553-1463.