Ethanol and the Environment

Ethanol, a Healthier Fuel Option

Choosing ethanol-blended fuel is a simple way for Americans to improve their health and better the environment for their families and neighbors. Ethanol has a major role to play in securing cleaner air, cleaner water, and healthier soils.

Ethanol use plays an incredibly important role in reducing tailpipe pollution harmful to human health.   

• Carbon monoxide can cause harmful health effects by reducing oxygen delivery to the body’s organs. 
• Exhaust hydrocarbons contribute to ozone, irritate the eyes, damage the lungs, and aggravate respiratory problems. 

• Nitrogen oxides act as a respiratory irritant, causing airway inflammation, reduced lung function, and increased asthma attacks. Long-term exposure causes chronic obstructive pulmonary disease (COPD), cardiovascular issues, and premature death.

• Air toxics can cause cancer and reproductive effects including birth defects.
• Fine particulate matter can pass through the throat and nose and enter the lungs, causing serious health effects.

Adding ethanol to gasoline dilutes and displaces the most harmful gasoline components - air toxics including sulfur, benzene, toluene, and xylene - that are major contributors to smog formation. Because oxygen-rich ethanol is a cleaner burning fuel, its use directly lowers the emissions that create urban haze and poor air quality. A 2025 study by the Hormel Institute, in collaboration with the University of Minnesota and the University of Illinois Chicago, found that increasing the use of ethanol reduces carcinogenic exposure, thereby decreasing cancer risk for American families.

A 2022 vehicle test by the University of California, Riverside found that simply switching from E10 (gasoline blended with 10% ethanol) to E15 (gasoline containing 15% ethanol) reduces emissions as follows:

• Particulate matter 18%
• Hydrocarbon gases 5-8%
• Carbon monoxide 17%
• Nitrogen oxide 3%

Ethanol Reduces Greenhouse Gas Emissions 

Ethanol has a proven track record of cutting GHG emissions from transportation. The use of ethanol in gasoline in 2025 reduced CO2-equivalent greenhouse gas emissions from transportation by 58.8 million metric tons. That's equivalent to eliminating: 

• 13 million cars from the road for an entire year
• Annual emissions from 16 coal-fired power plants
• Emissions from 490,000 roundtrip flights between Los Angeles and New York City

The Low Carbon Solution

Renewable fuels like ethanol are available now at a low cost to help decarbonize liquid fuels. Ethanol greenhouse gas emissions significantly—by 44 to 52% compared to gasoline, according to the Department of Energy's Argonne National Laboratory.  Similarly, researchers from Harvard, MIT, and Tufts concluded that today's corn ethanol offers an average GHG reduction of 46% versus gasoline. Emerging technologies promise to boost that reduction to near 70% in the next few years, according to USDA. And ethanol made from corn kernel fiber and other cellulosic feedstocks is already delivering reductions of 80% or more.

How does this work? Plants that are made into renewable fuels absorb carbon dioxide from the atmosphere as they grow, and that same amount of carbon dioxide is re-released when the fuel is produced and combusted in an engine. In this way, ethanol and other renewables simply recycle atmospheric carbon. Even when the energy use and emissions related to the full production process are accounted for, ethanol delivers significant GHG savings compared to the fossil fuels it replaces. Learn more about ethanol's carbon benefits.

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