The US Environmental Protection Agency (EPA) is gathering input on whether emissions standards should be set for the leaded fuels used by piston-powered general aviation aircraft, restrictions that could require the use of automobile gasoline or other alternatives for about 200,000 aircraft in the USA.

Prompted by a petition by Friends of the Earth, the agency is asking the public for a wealth of information by March 2008 to assess the impacts of lead in the air, ground and soil on or near airports where leaded fuels are used in a bid to judge whether new rules might be needed.

Included is a request for "information regarding the number of children six years and younger, the number of schools, daycare facilities, retirement homes, and the socioeconomic status of the population" in the vicinity of those airports.

The EPA says the lead can cause neurotoxic effects, including loss of IQ, as well as impacts on the immune system and other "serious adverse health effects". In the USA, leaded fuels were banned for use in automobiles after December 1995.

GA aircraft burned 1.06 billion litres (280 million USgal) of leaded fuel in 2006, with each litre containing about 0.56g (0.02oz) of lead for 100-octane "low-lead" (100LL) gas, according to the EPA. In total, it says the sector represents the "largest source category" for lead emission in the USA, generating 491t in 2002, or 29% of the air pollution emissions inventory.

The EPA cites Experimental Aircraft Association (EAA) figures that show ethanol-free unleaded gasoline can be used in 40% of the piston-powered fleet under supplemental type certificate approvals, although most high-performance aircraft cannot use the fuel. EAA and other GA advocacy groups, including aircraft manufacturers, have been exploring high-octane lead-free fuel alternatives under the auspices of the Coordinating Research Council.

Source: Flight International