My environmentally awesome friend Anthony adds this caveat. . ."we're talking about growing corn for ethanol in the US. Brazil, for example, does great things making ethanol from sugar cane waste"

The researcher makes the point that it doesn't matter how the ethanol is made in terms of health effects -- when it combusts in the your engine, it produces the same emissions that are causing the health effects modeled.

I found this article to be an interesting example of the way in which disciplines seem to have trouble aggregating their work. This quote was particularly revealing:

"The question is, if we're not getting any health benefits, then why continue to promote ethanol and other biofuels?"

The answer to that is clear. Health was not the driving factor in promoting ethanol or biofuels. Energy security is the main goal, with global warming playing a supporting role. To address the question of whether or not ethanol should be supported, one now needs to trade off the health effects of ethanol against the energy security/climate change benefits. Unlike the health effects, those benefits are highly dependent on how the ethanol is produced.

Any comments from health students on whether or not one should consider the health outcomes mentioned in this study to be "major" or serious? Should this be considered a reason to end ethanol implementation?

I've heard that this new study uses rather old numbers, and that it's conclusions are dubious at best -- I'll be back with further comment once I figure this out since it has to be part of my APA now...

Really though, Gasoline used to be much worse on air pollution than it is today. The reason? Because of California air quality regulations, Gasoline producers came up with Reformulated Gasoline (RFG) that performs better with less emissions. I think there's a case here for process innovation - if we deploy ethanol and maintain air quality standards, can we come up with a solution? I think the answer is Yes.

To build off of what Christine is saying, don't forget that we used to burn lead in gasoline until we realized that it was no good. And then we stopped.


Last semester, wonderful Sheryl R. and I (and a Ph.D candidate in SPH) put together a really interesting program design for Rob's class. We looked at specifically the Bay Area's Spare the Air program. We did a really interesting causal chain comparison between Spare the Air to driving less Emissions and Health impacts - and the link is not very clear. Not to diminish what Jacobson is saying - but the problem might end up being a wash. I would be interested to see what Christine's numbers show from her APA.

I think this is a good example of who sets the research question and the effects this may have. As Jameel says, no one thought of studying the health effects because the objective was energy. Similarly, the EBI's objectives are to study energy. So, questions such as health effects, impact on agriculture in 1st or 3rd world, on soil or on the water supply, may not get researched. I don't this is necessarily a fault of the EBI -its a collective responsibility to ask these questions- but to the extent the EBI, with all its funding, can narrow the scope of the debate, then there is a problem.

In this study, Jacobson concludes that if ALL vehicles in the United States were to be run on E85 in the year 2020, then 185 more people would die per year from air pollution than they would if all vehicles at this time were totrun on gasoline. The cause of the majority of the increased deaths found in the study were due to an increase in ground-level ozone in the Los Angeles area and others were from an increase in ozone in the Northeastern States. This increase in ground-level ozone was due to ethanol’s comparatively lower NOx emissions and higher reactive organic gas emissions. In these two areas, the current mix of NOx to other components of ground-level ozone is such that reductions in NOx actually increase levels of ground-level ozone. Thus, Jacobson’s predictions are based on assumptions regarding not only the overall level air pollution in these areas in 2020 but on the ratios of specific pollutants to each other. In recent years, policy and innovation have spurred the use of less-polluting renewable energies and energy efficiency. Reliance on these cleaner sources of energy is on an unprecedented upward trend. Future policies and technological breakthroughs are sure to create even further change. As energy consumption is the major source of air pollution in the U.S., it does not seem reasonable to think that one can predict ratios of air pollutants in specific areas in the U.S. thirteen years from now. Further, it is extremely unlikely that the every car in the United States will run on ethanol in 13 years. To begin with, many of the cars being produced today which cannot run on ethanol are likely to still be running in 13 years. Further, many new, cleaner vehicles such as hybrid electric, plug-in hybrid electric, and electric-only vehicles will likely be in use in the year 2020. This makes predictions based on an all ethanol fleet in 2020 irrelevant as well. Jacobson also bases his comparison between an all gasoline fleet in 2020 and an all ethanol fleet in 2020 on the assumption that future vehicle regulations will require a 60% reduction in pollutant emissions by this time. In his conclusion, Jacobson himself states, “Because both gasoline and E85 emission controls are likely to improve, it is unclear whether one could provide significantly more emission reduction than the other.”


While this study shows the need for further research on the pollutant emissions of vehicles running on ethanol, it does not provide conclusive evidence that expanded ethanol use will increase overall air pollution or the number of air pollution related deaths.