What's for dinner? Corn ethanol, feedlots and what you eat

by Annie Shattuck
April 10, 2008

The debate over renewable energy is raging. The U.S. Congress recently passed a renewable fuels mandate which will effectively create an artificial market for at least 15 billion gallons of corn ethanol per year. Numerous studies have criticized ethanol's environmental footprint. From negligible greenhouse gas savings to increased ground level ozone, and dependency on high-input agriculture–corn ethanol's critics have painted a picture of a costly band-aid for our energy crisis.

None of this analysis examines the full cost of the corn ethanol boom, which actually creates more by-product than it does fuel. Ethanol from corn produces seven pounds of by-product for every gallon of ethanol. This by-product is already in our food. If you eat beef, chances are you have eaten cattle fattened on this ethanol waste.

Dried distillers grains with solubles (DDGS) are the leftovers after corn has been milled and fermented into ethanol. Cattle nutritionists recommend including ethanol by-products in cattle diets at 20%-40% maximum. The quantity of distillers grain available is dictated by government incentives for fuel refining, leaving the ethanol industry to engineer demand for its waste. Without the sale of these ethanol by-products, corn ethanol is vastly less profitable. Industry claims that co-production of distillers grain with ethanol is a win-win proposition. Cattle producers get economical, high-protein feed, and America gets renewable fuel. However, the market for distillers grain is limited, and their disposal, like any other industrial by product, comes with costs to the environment, the economy and public health.

The Problem with Ethanol By-Products

Concentrated phosphorus and nitrogen in cow dung

Feeding distillers grain to cattle increases the amount of nitrogen and phosphorus in their feces. Unfortunately, the ratio of phosphorous to nitrogen is so high in this cow dung that it is of little use as a fertilizer. Cows fed a diet that includes 40% distillers grain, have fecal material with 41% more phosphorous and 33% more nitrogen than cows fed conventional feedlot diets. More than 40 percent more land will be needed to treat the waste of cows consuming this by-product if it is disposed of by spreading it over fields. Even if the proper amount of land can be dedicated to treating wastes, water quality around feedlots will likely worsen. Eutrophication—the process by which streams with high-nutrient runoff clog with vegetation, reducing oxygen in the water, and killing fish and other aquatic organisms—is a proven result of large-scale cattle and dairy operations. More nitrogen and phosphorous cycling through these operations will intensify the deterioration of streams and rivers.

Increasing nitrogen cycling through feedlots also increases greenhouse gas emissions. Nitrous oxide, a greenhouse gas 296 times more potent than carbon dioxide, is a major toxic emission from large-scale agricultural operations. Nitrous oxide forms when bacteria naturally present in soils convert biologically available nitrogen to a gas bound with oxygen. In areas where nitrogen runoff is high, nitrous oxide emission is also high. Cows fed a diet of 40% distillers grain increase the amount of available nitrogen in their excrement by 33% percent. The amount of available nitrogen that forms greenhouse gases varies according to treatment methods applied to the waste. With over 200 billion pounds of by-product slated to be produced annually under Congressional ethanol targets, feedlots all over the nation will increase their nitrogen and phosphorus emissions dramatically.

Food safety: Sulfur, polio and E. coli

The market for ethanol by-products is limited due to sulfur residues. Sulfuric acid and other sulfur compounds used in the distilling process combine with naturally-occurring sulfur in corn to produce unhealthy and potentially lethal levels of sulfur in distillers grain. The sulfur levels in ethanol by-products vary between plants and even between batches at the same plant, making it difficult to label or control. Sulfur, in excess of 0.4% in cattle diets will cause polioencephalomalacia, a deadly form of polio that produces brain lesions. The fine nutritional testing necessary to feed a diet heavy in ethanol waste favors large feedlot operations that can afford to test their water supply and distillers grain for sulfur. Smaller ranchers are unlikely to be able to use ethanol waste to the same degree as feedlots, putting family cattle operations in direct competition with ethanol plants for feed corn.

Feedlots that use ethanol waste also threaten the food supply with E. coli outbreaks. A recent Kansas State University study shows that distillers grain promotes the growth of E. coli. The study's authors warn of “serious ramifications,” predicting strong resistance to feeding ethanol waste. Cattle fed brewers grains, a similar product, are six times more likely to have E. coli in their feces than cattle fed real corn. E. coli outbreaks in factory farms are common. The use of ethanol by-products will doubly increase this phenomenon, both increasing the presence of E. coli and expanding the industrial model that makes our food system vulnerable to contamination in the first place.

The feedlot-refinery connection

Ethanol refineries and factory-style feedlots go hand in hand. For example, at an ethanol plant owned by E3 BioFuels corporation in Mead, Nebraska, manure from a 28,000-cow feedlot helps to power a 25 million gallon per year ethanol plant. In this system, the corn waste from the refinery makes up 40% of the cattle's diet. E3 plans to build larger ethanol plants with feedlots of 60,000-120,000 cattle. Such plants bring in a few jobs, but all of the added value of the ethanol stays with the refiner, while the community is left with despoiled water supplies, bad air quality, and all the other environmental problems associated with feedlots and refineries of that size. The pairing of feedlots and refineries makes sense from an industrial standpoint. Up to one third of the energy produced from ethanol is lost in the drying and shipping of its by-products. Pairing ethanol plants and feedlots eliminates drying and transportation costs. As more ethanol refineries are built around the country we can expect feedlots to follow, spoiling waterways and threatening food safety as they go.

Corporate consolidation and consumer choice

Corporate consolidation is occurring rapidly in the ethanol industry. Of the 119 ethanol plants operating in 2007, 49 of them were owned and operated by farmer cooperatives. But once ethanol refineries currently in construction come on line, farmers will only control 20% of the nation's ethanol (and distillers' grain) production capacity. Just as the refining business favors large corporations, the by-products industry will favor large corporate farms and feed lot operations. As ethanol drives corn prices up and the excess corn by-product becomes cheaper, factory feedlots and dairies are likely to edge out smaller operations that can't or don't want to use distillers grains. Consumers who prefer to avoid factory beef will have to buy from the small number of ranchers who sell to specialty markets.

READ THE REST: http://www.foodfirst.org/en/node/2079