Ethanol raises ozone pollution more than petroleum

Saturday, October 08, 2016 by: Julie Wilson staff writer
Tags: ethanol, ozone pollution, petroleum

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(NaturalNews) While some regard ethanol as a cleaner, safer and more environmentally friendly biofuel than gasoline, critics say its effect is as bad or even worse for nature than regular oil, as concluded in a report by Malaysia's The Star.

New research regarding the so-called eco-friendly fuel came as a surprise to scientists when they discovered that drivers using ethanol in Sao Paulo, Brazil, was linked to more ozone in the local environment. Ozone is a major pollutant made from chemical reactions between nitrogen oxides and volatile organic compounds like methane and carbon monoxide, from the burning of fossil fuels, as described in a report by Responding to Climate Change.

Experts say that breathing in ozone can cause inflammation in the deep lung, affecting functionality, according to a review reported [PDF] in the American Journal of Preventative Medicine in 2008. Additionally, further data analysis discovered ozone pollution to be responsible for around 200,000 premature deaths annually.

The study, published in the journal Nature Geoscience, was initiated after drivers in Sao Paulo switched from burning ethanol to gasoline due to price hikes. At least 40 percent of light-duty vehicles in the city are capable of running on either fuel. Researchers set up a lab to study the effects after the percentage of those using petroleum increased dramatically from 14 to 76 percent.

During the percentage increase, ambient ozone concentrations fell by about 20 percent, according to researchers.

"The study is the first large-scale effort to measure how switching between ethanol and petrol affects air pollution," reported The Star. "It arrives amid a debate in the United States and other industrialised countries over the environmental benefits of ethanol, a renewable fuel made from plant matter."

While the findings were unexpected, researchers warned not to generalize the study to include other major cities, because each region's "specific climate, vehicle fleet, local industry and traffic patterns," are all contributing factors that differ according to place.

"Ozone and nitric oxide are both contributors to urban smog, so depending on how well a city is able to mitigate air pollution, ethanol may not be the 'green fuel' that it is often called," said Franz Geiger, a professor of chemistry at Northwestern University who worked on the study.

U.S. expert Sasha Madronich published a written response to the research, agreeing that the findings "did not represent a thumbs up for burning gasoline," according to The Star.

Middle America home to ethanol production

Iowa is the lead producer of ethanol in the U.S., supplying nearly 30 percent of all biofuel, which is made primarily from corn containing octane and oxygen. According to the Iowa Corn Growers Association, global ethanol production reduced greenhouse gas emissions by 100 million metric tons last year, which is equivalent to removing 20.2 million vehicles off the road.

With nearly 40 percent of U.S. corn cultivation going toward ethanol production, food prices have increased significantly, leaving some questioning whether or not using food for fuel is the best solution.

Brazil uses sugar cane to produce ethanol, and the prices fluctuate according to the market, unlike gasoline, which is controlled by the government.

Researchers suggest that the reason ozone concentrations worsened after ethanol use rose in Sao Paulo could be because burning gasoline creates more nitrogen dioxide emissions.

"At certain high levels, nitrogen dioxide combines with hydroxyl radicals, a short-lived type of atmospheric chemical that cleans the troposphere of ozone, among other pollutants," reported The Star.

Scientists note that petrol was linked to other problems like increases in carbon monoxide and nitrogen oxide emissions, but the effect of other pollutants, such as fine particles, was not studied but is expected to be reviewed next.

An expert at the Renewable Fuels Association said the Sao Paulo results were not applicable to the U.S. because vehicles in America comply with different emissions controls requirements that are more "stringent" than in Brazil.

Additional sources:

http://www.rtcc.org

http://www.thestar.com.my

http://download.journals.elsevierhealth.com [PDF]

http://www.iowacorn.org

http://www.pacificethanol.net

http://www.iowarfa.org/ethanol_facts.php