Say you bought a car in 2001 – a Volkswagon, for example. Let’s also say that you thoroughly read your car’s warranty detailing what type of gasoline to use. Filling up the pump shouldn’t be a big deal, right?

Wrong – if the ethanol industry gets its way.

Growth Energy, an ethanol trade association, petitioned the E.P.A. back in March to increase the allowable amount of ethanol in gasoline from 10 percent (10E) to 15 percent (15E). The group, co-chaired by former Democratic presidential candidate Wesley Clark, claims this increase would be harmless, resulting in cleaner air and posing no risks to vehicle engines.

But, Growth Energy’s proposal is anything but harmless.

Let’s return to the example of the 2001 Volkswagon. Most vehicle manufacturers specifically instruct consumers in warranty agreements not to fuel their vehicles with ethanol blends greater than 10E. Available research on “legacy” fleets, or cars currently on the road, shows that lots of problems can occur if higher ethanol blends are used, including damage to engine components and control systems, and increased combustion temperatures (things all vehicle-owners want to avoid).

If the E.P.A. approves 15E ethanol blends, this kind of damage could occur to many consumers’ vehicles. And, since consumers bought their cars with a warranty stating not to use blends over 10E, there’s a chance they won’t be eligible for warranty claims should any damage occur.

As if that isn’t reason enough to oppose the increase, ethanol also could pose more dangers to your health. Research – for example, a 2007 Stanford University study that explored the effects of ethanol vs. gasoline – shows that ethanol is related to ground-level ozone, which can cause or worsen asthma and other respiratory problems.

The environmental benefits are unclear – the E.P.A. is currently studying the lifecycle greenhouse gas impacts of ethanol and other biofuels. So, it would be premature for the E.P.A. to permit 15E before it has publicly released the results of its study.

All this information is pretty disheartening, but luckily, there is something you can do about it. The E.P.A. is asking for public comments on Growth Energy’s petition for an ethanol increase. This is your chance to speak out against the dangers of 15E and counter the ethanol industry’s efforts.

Public Citizen has set up a page for you, with a sample comment, that you can send straight to the E.P.A. It will only take a minute. So take action today!