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Welcome to PSR's Environmental Health Policy Institute, where we ask questions -- then we ask the experts to answer them. Join us as physicians, health professionals, and environmental health experts share their ideas, inspiration, and analysis about toxic chemicals and environmental health policy.


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Corn-Based Ethanol: A Win for Public Health and the Economy

Posted on December 12, 2012

By William C. Holmberg

Asthma, $16 billion.  Premature births, $26 billion.  All cancers, $227 billion.  Autism, $126 billion.  Heart disease, $272 billion.  Obesity, incl. Type 2 diabetes, $190 billion.  These are government estimates of the annual costs to society of some of the nation’s leading health disorders.  Mounting scientific evidence suggests that they share a common linkage: they can be triggered by ubiquitous, nano-sized, particle-borne carcinogens known as PAHs (polycyclic aromatic hydrocarbons), the primary urban source of which is gasoline aromatic compounds used to enhance octane ratings.  PAHs are not only carcinogenic and mutagenic, they are genotoxic, and one of the most pervasive and persistent endocrine disruptor compounds found in the urban environment.  Experts worry that as advanced  direct-injected, high compression/turbocharged engines are used to meet new fuel efficiency and carbon rules, urban PAH emissions will likely increase unless fuel quality is improved.  When the medical costs associated with the PAHs’ carcinogenic/mutagenic emissions are considered, higher quality ethanol gasoline blends could save Americans tens of billions per year in reduced health and energy costs, while also substantially reducing the transportation sector’s carbon footprint and dramatically improving our quality of life, especially for urban youth and those who live near congested roadways. 

Since the elimination of lead in the 1980s, petroleum refiners have synthesized gasoline aromatics from crude oil via an energy-intensive process.  Aromatic compounds are frequently the most expensive components in gasoline, and their costs go up as crude oil prices rise.  One piece of goods news:  recent research by Ford Motor Co. and other experts has found that partially replacing carcinogenic aromatics with higher blends of ethanol (E-30, which is 30% ethanol mixed with 70% gasoline), could reduce particle-borne toxics and black carbon emissions by as much as 45% or more.  Motorists would benefit from higher octane (94-plus,  compared to 87 with today’s 10% ethanol blends), better performance, and cleaner-burning fuels. This would also save money since ethanol is less expensive than aromatics from crude oil. Even more good news: Congress instructed EPA to reduce gasoline aromatic levels to the greatest degree possible in the 1990 Clean Air Act Amendments, so new legislation is not needed.  EPA could act to improve gasoline quality standards in the upcoming Tier 3 rulemaking early next year.

Now for the bad news:  the vast financial resources of entrenched international oil and related interests are being mobilized to prevent ethanol from building upon its already significant contribution to U.S. health, fuel supplies and the economy.  Multi-million dollar media attacks have inaccurately, but often successfully, portrayed ethanol as a threat to food supplies and the environment. Nothing could be further from the truth.  First of all, 98% of U.S. corn is not directly consumed by people, but instead used as livestock feed and for other purposes. The use of corn for ethanol leaves much of the corn’s protein available to serve as feed.  When the starch portion of an acre of corn is converted to ethanol, the feed grain that remains has as much protein and other equivalent high-value feed products as contained in an acre of soybeans.  Since corn yields are nearly four times greater than soybean yields, the economically and environmentally smart thing to do is to first process the corn to ethanol.  Doing so results in the same amount of protein and feed co-product equivalents offered by an acre of soybeans, but with the additional multi-billion dollar per year bonus of the corn ethanol industry’s job creation, health cost savings, oil import reduction, reduced gasoline prices, and environmental benefits.

Corn is categorized as a C4 plant, meaning it has a superior structure in utilizing carbon fixation through photosynthesis.  This provides corn with the extraordinary ability to operate better than other categories of plants in conditions of drought, high temperatures, and nitrogen or CO2 limitation.  Additionally, corn’s genetic makeup allows it move more fertilizer nutrients, such as nitrogen and phosphorous, to its root zone where it is used for growth rather than polluting ground and surface water.  A multi-year USDA research project recently confirmed that no-till corn equaled switchgrass in SOC (soil organic carbon) formation, and that over half the increase in SOC was below one foot depth.  The researchers estimated that deep soil SOC sequestration benefits of corn have been understated by 60 – 100% in modeling done to date.

So-called “food vs. fuel” attacks have been conjured up by big oil as well as processed food producers and animal feeders who want subsidized U.S. corn to boost their profits. The ethanol industry eliminated the need for corn subsidies, thereby raising the market value and making corn-growing profitable throughout the world.  This led to slightly higher corn production in 2012 than 2011, even with the impact of the drought in America. 

Even Michael Pollan, an American author, journalist, activist, and professor of journalism at the UC Berkeley Graduate School of Journalism as well as a frequent critic of the current agricultural system, has effusive praise for corn’s efficiency as a crop.  “Few plants can manufacture quite as much organic matter (and calories) from the same quantities of sunlight and water and basic elements as corn.”  Pollan goes on to praise corn’s ability to extract carbon from the air in his book, The Omnivore’s Dilemma: A Natural History Of Four Meals, when he states, “The C-4 trick represents an important economy for a plant, giving it an advantage…By recruiting extra atoms of carbon during each instance of photosynthesis, the corn plant is able to limit its loss of water and ‘fix’—that is take from the atmosphere and link in a useful molecule—significantly more carbon than other plants.”

Substituting ethanol—derived from one of nature’s most efficient converters of sunlight and water, most efficient carbon-fixing plants, and a highly efficient source of protein—for carcinogenic, oil-derived, carbon-intensive and costly aromatic hydrocarbons offers society a rare win – win – win proposition.

The views expressed in these essays are those of their respective authors and do not necessarily reflect the views of Physicians for Social Responsibility.


Lynn Ringenberg, MD said ..

diversion of food ( corn) to fuel...who suffers? As stated in an excellent article in Sundays New York Times, Jan 6, 2013, that land once devoted to growing food for human consumption is now making lots of money as fuel for cars, which most people in the poor countries where this is changing the local-&farmer landscape, like Asia, Africa and Latin America, don't even have cars. The article says " roughly 50% of Guatemalan children are chronically malnourished, 4th highest rate in the world, according to the United Nations. More corn from developed countries, like the U.S., is now going to make biofuel and not being exported for food to poor countries and what is exported is too expensive to buy. Is this ethically acceptable? NO, says the United Nations World Food Program head. Perhaps once the worlds poor & starving are fed and out of danger of dying from lack of food, then we should consider biofuel production as a win.

January 7, 2013
Kelly Baraka said ..

There is NO feed value lost when corn is processed to removed the sugars to produce ethanol. The result is called Dried Distillers Grain (DDG) and has been shown to produce healthier cows that put on weight faster. Cows do not need the sugars in corn-it causes indigestion and gas (another HUGE green house gas). So, if your going to grow corn as cattle feed anyway, why not remove the ethanol first? This creates 2 superior products-DDG and non-polluting ethanol that can be used to power any car on the road that has fuel injectors. There are other plants that have a far better yield of ethanol and can be grown on non-arable land-sewage marshes, deserts, etc. Also, all the waste from food processing plants, garbage, etc. could be utilized. There are lots of options other than corn.

January 7, 2013
Paul Geraets said ..

When you study all the inputs that go into an ethanol plant compared to all the outputs valued at known btu's the ethanol industry is a winner and is a great transformer of hard to handle (for 99% of consumers without a CNG vehicle) natural gas into a portable liquid fuel (ethanol) that is more environmentally sound than fossil based petroleum. We have an excess of natural gas with the increase in shale oil therefor it is the best valued fuel on a btu basis, but falls painfully short as a viable competitor to liquid fuels for a whole host of reasons which the marketplace may solve eventually. Switch grass can't be planted, fertilized, swathed, baled, transported, stored, ground up, processed without more btu than it produces nor is it sustainable even after years of research. Maybe someday it will become viable and could be sustainable in some areas someday. Corn is misunderstood by some but without its current productivity and constant efficiency gains the world in which we live in would look different. The rising standard of living in emerging countries and fuel prices has had more affect on food inflation than the ethanol industry has had on food prices. Today the ethanol price at the plant is $2.00/ gallon add 50 cents for state and federal gas taxes and you can see ethanol is a viable fuel competitor with local pump prices at $3 bucks here in SD. As a reminder the blenders credit that blenders of ethanol were receiving ended over a year ago now. Blenders of ethanol are not necessarily producers of ethanol.

January 5, 2013
Catherine Thomasson said ..

I would really appreciate the USDA reference for corn-based ethanol using no-till methods. That may be as good as switchgrass but most of the corn is produced using tillage, fertilizer (oil based) heavy machinery--diesel. Given its recent response to drought, not as drought resistant as expected. I would really appreciate a reference to a recent carbon analysis of this crop for ethanol rather than others. thanks so much for writing for the institute.

January 4, 2013
Aaron Kreider said ..

Will ethanol reduce carbon emissions by 80% and help stop global warming? Will ethanol cause particulate emissions that cause asthma? Is ethanol sustainable? Will ethanol increase food prices and cause millions of people to starve as Oxfam believes?

January 3, 2013
Dave Greene said ..

What about the EROEI question, though? Doesn't growing corn require fossil fuel inputs (fertilizer, gasoline for tractors, etc.)? The corn-growing and ethanol-making industries don't run on the fuel they produce. If they did, there would be barely any ethanol left over. Once you've burned enough ethanol to run the tractors and factories to grow and process the corn, maybe 10% of the ethanol remains. (It's 14% under ideal growing conditions, according to , and in Texas and Missouri there was a net energy loss. And this was in 2010, before the drought...!) When you look at the whole picture, this corn-for-fuel idea looks suspiciously like an exercise in futility: in practice, you're still burning the same problematic fossil fuels, in roughly the same quantites, to make this "clean-burning" ethanol. The big unanswered question in this article seems to be: what percentage of the feed value of corn is lost by processing it for ethanol first? It doesn't much matter if there's as much protein left as in an acre of soybeans -- what matters is if more corn has to be grown (using yet more fossil fuels) to replace the missing starch and feed the same livestock.

January 3, 2013

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