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E85 as a fuel? Bad. E85 (modified) as a drink? Bad. E85 is Bad.

May 4th, 2007 by seok · 9 Comments

It’s spring. Terrible spring. I hate spring. This is when pollen resumes its course in making my life miserable. (I have *seasonal* allergies. It is worst in spring. Fortunately, I don’t have allergies in winter, when I’m most active.)

Yesterday (May 3, 2007) on the ABC Evening New, there was a story about allergies and global warming. A doctor from the the American Academy of Allergy, Asthma and Immunology said that an increase in allergy and asthma patients is probably due to more pollen production, which in turn is probably as a result of greenhouse gases, global warming. I know from a plant physiology class I took as an undergrad taught how flowering plants *love* CO2 enriched environments. With more CO2, these flowering plants are able to invest more energy into “making love” and making many of our lives miserable. A typical environmental advocate would say, to cut down these types of allergens in the air is–naturally–to reduce CO2 emissions.

OK, but what does this have to do with ethanol (in the title)? Well, besides associating ethanol with your favorite drink (or whatever), many environmentally conscious people are now thinking E85!

E85 (85% EtOH and 15% gasoline) is believed to produce much less greenhouse gases during combustion.

Recently (April 18, 2007), there was a study (soon to be published in ES&T) on E85′s impact on human health conducted by Mark Z. Jacobson that came out. Those who have studied atmospheric modeling may recall the name Mark Z. Jacobson at Stanford. He’s the author of one of the books in atmospheric modeling, the Fundamentals of Atmospheric Modeling.

I think Jacobson justifies well on why he conducted this study of E85 on human health.

With respect to air pollution, several studies have examined emission differences between gasoline- and ethanol-fueled vehicles (9-19). However, no study has examined the spatially varying effect on cancer or ozone-related illness throughout the United States that might result from a conversion to ethanol. Such a study is important because previous introductions of chemicals (e.g., tetraethyl lead, chlorofluorocarbons, DDT, dioxins) without an analysis led to damaging consequences. Air pollution (indoor plus outdoor) is also the seventh leading cause of death worldwide (20), so any change in fuel that could affect mortality should be examined prior to its implementation.

If anyone has read Rachel Carson’s Silent Spring, you know that Jacobson is right about the possible consequences of introducing chemicals without thorough analysis. Although the EPA should be doing these analysis, they never do a good job at it. They are, after all, a government agency, and money and politics are doing the work…

Anyway, Jacobson’s study is all modeled work so it is all speculation. To quickly summarize what he did, he used a nested global-through-urban GATOR-GCMOM model. (This is a model that Jacobson built.) He simulated scenarios at the U.S. scale and in the Los Angeles region in the year 2020. Why 2020? Jacobson believes that “flex-fuel cars replacing current gasoline vehicles, most of which cannot use E85, could substantially penetrate the U.S. vehicle fleet only by 2020.”

So, what kind of results did he get from the computer?

(First, note that major human carcinogens emitted during gasoline and E85 combustion are formaldehyde, acetaldehyde, 1,3-butadiene, and benzene.) His computer tells him that E85 vehicles reduce atmospheric levels of two carcinogens, benzene and butadiene, but increase two others-formaldehyde and acetaldehyde. This probably means that cancer rates for E85 are no different to those for gasoline. However, in some parts of the U.S., E85 combustion increased ozone levels–(remember the ozone cycle in the troposphere?).

We all know that ozone is toxic even at low levels. It can decrease lung capacity, inflame lung tissue, worsen asthma and impair the body’s immune system.

Jacobson summarizes his study saying,

a future fleet of E85 may cause a greater health risk than gasoline. However, because of the uncertainty in future emission regulations, E85 can only be concluded with confidence to cause at least as much damage as future gasoline vehicles. 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. In the case of E85, unburned ethanol emissions may provide a regional and global source of acetaldehyde larger than that of direct emissions.

*Ouch* for E85 advocates! If Jacobson is right, do you think we should still push for E85 despite the health risk? With where we are heading at, either way we are screwed. Seriously, I would have to say no. Pushing for E85 gives us no real benefit. What is the point cutting greenhouse emissions using E85 if it will kill us? We should really be promoting transportation that utilizes power generation in forms beyond combustion (i.e. solar, wind, and electro-chemical). No combustion means virtually no emissions.

Oh by the way, “drinkable” E85 (85% EtOH and 15% H2O, that is a 170 proof spirit) will probably kill you like the smog made from E85. With E85, my head will be in a larger cloud of smog. E85 in any form is just no good.

Tags: general interest · global warming · health · Uncategorized

9 responses so far ↓

  • 1 Mark R // May 4, 2007 at 5:32 am

    General Motors is heavily promoting E-85. Although my reaction is unscientific, this means that GM thinks this is the cheapest way to address the issue of reducing gasoline in automobile engines; it has nothing to do with being environmentally sound.
    The rapid creation of ethanol plants ensures that this system of fuel production will become entrenched in the US before it ever disappears. With a reliable network of gas stations, along with Big AG support, it will be difficult to stop what has already started.
    American farmland will be largely given over to growing fuel for cars, and we will eat tainted food products produced in China. Where’s the revolution?

  • 2 Pete // May 4, 2007 at 6:08 am

    As a particle guy, I think this article avoids the particulate matter implications. Jacobson mentions one study which shows an increase in particle mass and number, but decides to model particles with no mass difference between E85 and gasoline.

    As there were previous posts on primary and secondary organic aerosol( 1, 2), I won’t go into details but will speculate that secondary organic aerosol production would decrease with E85 since the gas phase organic carbon emitted with E85 appears to be lower molecular weight compounds (more volatile), consequently it will have a harder time finding it’s way into the organic phase.

    If there truly is a reduction total particle mass (primary + secondary) then this will be a health benefit of E85.

    (Note: I’m not an advocate of E85, I don’t think committing our food source to our cars is the solution to our climate problem.)

  • 3 seand // May 4, 2007 at 7:17 am


    There are also very serious and legitimate doubts about whether ethanol production in its current form in the U.S. (i.e. growing corn) even reduced GHG emissions, relative to gasoline. This is because of the large energy input in the form of plowing and petrochemical-based fertilizers, as well as land-use change, as I understand it. I recall hearing that ethanol produces 85% of the GHG’s relative to gas, but in the last few weeks I heard about a paper that claims that ethanol is actually WORSE than gas. I’ll see if I can dig up some references. Good post!

  • 4 Jamie // May 4, 2007 at 8:53 am

    Good work Brian and Sean.

    Another huge sink of energy in producing ethanol is separating the ethanol from the ferment. I would really like to see an analysis of greenhouse gas emission from ethanol combustion going all the way from seed to tailpipe. I doubt that using petroleum products to produce ethanol is more efficient than just burning the petroleum products straight up. If renewable resources are used to make the ethanol, then maybe we could get somewhere, but the new pollutants produced by an ethanol-based economy are still a real serious issue to be tackled as Brian and Prof. Jacobson point out. BTW, I wrote an alternative fuels report in high school. Even back then (ca. 1990), the health risks of burning ethanol in our cars were well known. There were also lots of other problems like retooling the gas tank and intake manifolds to prevent explosions during operation, lower energy density and poor startability under cold conditions.


  • 5 seok // May 4, 2007 at 11:14 am

    I recall my father complain once that if we switched to an ethanol based fuel economy, we would have to worry more about soil and ground water contamination as ethanol is more corrosive to metal and more permeable through polymers currently used in cars. Also, if there happens to be a spill during transport…yikes! There are no bioremediation and natural attenuation for this low grade ethanol.

  • 6 christoffer // May 8, 2007 at 9:50 am

    I cant agree with the majorito here. for several reasons.
    1) the study is pure gueswork so untill we have some real numbers we dont realy know anything.

    2) E only conserns himself with “other polutants” and ignors the reductions in co2 levels. when you consider this then E85 is superiour

    3) E85 is not the end it is only a middle step to create a infrastructure. The nest step will be electric cars with Fuelcells runing on pure ethanol.
    these do not suffer the problems that ICE have.


  • 7 J // May 23, 2007 at 10:10 pm

    HEY Christopher!

    1) You’re using the same logic they use to ‘debunk’ Global Warming and convince roughly half of America that it’s all “$Green$” lies. If you haven’t noticed, computer models are never perfect – but do we use the Precautionary Principle or not? Choose one path and follow it.

    2) What’s the point of reducing CO2 if it doesn’t somehow prolong the human experience? The point of decreasing our impact on the globe is so that we may pass this wonderful place down to future generations. When people are dying/suffering from breathing the air, the whole ‘global warming’ point becomes moot.

    Don’t cause problems to cure problems!

  • 8 markxp // May 29, 2007 at 1:53 am

    the human race is an amazing species, we dont deserve the problems that the infernal combustion engine places on us in the name of profit. there is no point in using it for the solution has been around for 160 years in the form of free energy and dont just think im some crackpot do the reaserch go to google and type in free energy also have a look at youtube you will be pleasantly suprised then extreamly disapointed as no one will sell you any of the free energy devices. thanks to people such as nikola tesla we have the ability to completly abondon petro chemicals and ethanol think about it do you believe any of the world’s government’s want you to drive a free energy vehicle that dosent need to be refulled no ofcourse not otherwise every car would already be runing for free. dont be afraid to demand and embrace the technology once the public starts demanding it they will have no choice but to make and sell the devices. oh and also the I.C.E is overated beyond comparison electric motors are a supirior technology and are champions of efficiency and efficiency is what we need.

  • 9 Tom Pfingsten // Jul 16, 2007 at 4:07 pm

    I recently heard that the ratio of energy used to produce ethanol to the actual energy output of ethanol is 1:1.15, making it’s economical practicality less than attractive. Can anyone confirm this ratio. My source is an anti-ethanol scientist doing an interview on Minnesota Public Radio.

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