Report blasts corn-based biofuel health risks

First-generation biofuels are not only failing to deliver expected cuts in carbon emissions but also pose a significant health risk, according to a new study from the University of Minnesota.

The study, published in this month's Proceedings of the National Academy of Sciences, calculates that while second-generation cellulosic biofuels made from grasses and crops such as jatropha can deliver significant benefits, the economic costs to human health and well-being arising from corn-based ethanol are at least on a par with those accruing from petrol and can be far higher.

Researchers assessed pollutants emitted at all stages of the lifecycles of conventional gasoline, corn-based ethanol produced using three different methods, and four types of cellulosic ethanol and found that the combination of carbon emissions from changes in land use and particulates such as ammonia arising from fertiliser use and manufacture meant that corn-based ethanol had the highest environmental and health costs.

Using computer models, they calculated that the total environmental and health costs of gasoline are about 71 cents (50p) per gallon, while an equivalent amount of corn-ethanol fuel costs from 72 cents to about $1.45, depending on the technology used to produce it. In contrast, the same amount of cellulosic ethanol costs from 19 cents to 32 cents, depending on the technology and type of materials used.

Jason Hill, a resident fellow in the University of Minnesota's Institute on the Environment and lead author of the report, said that the research underlined the scale of the environmental damage that could arise from corn-based ethanol.

"Our work highlights the need to expand the biofuels debate beyond its current focus on climate change to include a wider range of effects such as their impacts on air quality," he said. "To understand the environmental and health consequences of biofuels, we must look well beyond the tailpipe to how and where biofuels are produced. Clearly, upstream emissions matter."

The research will strike another blow to producers of first-generation biofuels who have attracted widespread criticism for failing to deliver promised emission reductions and indirectly contributing to rising food prices.

However, investors in second-generation biofuels are likely to welcome further evidence supporting their claims that biofuels made from energy crops such as switch grass and jatropha grown on marginal land can deliver genuine cuts in carbon emissions while not impacting food production.

Stanley Wootlif, chairman of Jatropha specialist Viridas, said that the research echoed its own assessments of first generation biofuels.

"Biofuel from rape seed oil generate greenhouse gas emissions that are between one and 1.7 times that of fossil fuel, there are either no benefits or they are considerably worse," he said. "All the drivers now point towards second-generation fuels such as Jatropha."