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Will ethanol increase health problems in the U.S.?

blog A study bound to stir up the alternative-fuel world says ethanol might lead to an increase in respiratory illnesses.

Ethanol might help the U.S. cut down imports of crude oil and reduce greenhouse gases, but it also might cause respiratory illnesses to rise, according to a study that's bound to start arguments in the alternative-fuel world.

Stanford atmospheric scientist Mark Z. Jacobson created two simulations of air conditions in 2020 in the U.S. with a particular focus on Los Angeles. One scenario tried to predict what the air might be like if all of the vehicle fleet at that time ran on gas. The other scenario examined what would happen if these same cars ran E85, a blend of fuel that's 85 percent ethanol and 15 percent gas. The auto fleet can't be switched that fast, but this is what simulations are for, after all.

In the simulations, deaths from cancer stayed the same whether the cars ran gas or E85. The cancer-causing chemicals were different in each case, but the results were about the same.

In the E85 scenario, however, there was an increase of about 120 more deaths per year in L.A. and 200 nationwide because of ozone inhalation, or about a 9 percent increase over the gas situation. Ozone can inflame lung tissue (and kill microbes in small doses on plants and bottled water). Other potential problems were found too.

"We found that nationwide, E85 is likely to increase the annual number of asthma-related emergency room visits by 770 and the number of respiratory-related hospitalizations by 990," Jacobson said in a prepared statement. "Los Angeles can expect 650 more hospitalizations in 2020, along with 1,200 additional asthma-related emergency visits."

When everything is taken together, E85 will cause "at least as much health damage as gasoline, which already causes about 10,000 U.S. premature deaths annually from ozone and particulate matter," he stated in a prepared statement.

The negative effects were present whether ethanol was made out of corn, switchgrass or sugarcane.

Jacobson concluded by recommending that cars in the future might be better served by running on batteries or hydrogen.

Like almost every study in the alternative energy world, Jacobson's can be argued. Although E85 may cause as many premature deaths as gasoline, ethanol proponents can point out that Jacobson only looked at direct deaths. The study does not contemplate indirect deaths, i.e. people who die from increasing problems from global warming. Gas cars emit fumes that contribute to global warming. Ethanol emits fewer, and therefore will likely contribute less to these problems.

Manufacturing hydrogen also can contribute to global warming because the traditional manufacturing processes emit carbon dioxide. Solar-powered hydrogen production is being tested, but it's not in mass production.

Ethanol critics have also noted that it takes quite a bit of energy to produce and it requires subsidies to be competitive with gas. Proponents, meanwhile, note that cars running on batteries or hydrogen are expensive compared to gas or ethanol cars and can only go 100 to 200 miles between charges, a lot less than a car running on liquid fuels.