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EWG Debunks Ethanol Lobby's Push For Clean Air Act Waiver

EWG Debunks Ethanol Lobby's Push For Clean Air Act Waiver

Thursday, June 18, 2009

LINK: Science Analysis - Ethanol Health Risks and Engine Damage

The Honorable Lisa Jackson
U.S. Environmental Protection Agency
1200 Pennsylvania Avenue, NW
Washington, DC 20460

Subject: Clean Air Act Waiver Application to Increase the Allowable Ethanol Content of Gasoline to 15 Percent, EPA Docket EPA–HQ–OAR–2009–0211

Dear Administrator Jackson,

Environmental Working Group (EWG) is a non-profit public health and environmental research and advocacy organization based in Washington, D.C., with regional offices in Ames, Iowa and Oakland, California. We conduct research on sustainable agriculture and energy policies, and on health risks from exposures to industrial chemicals and pollutants. We advocate for policies that protect public health and conserve natural resources.

We are writing to urge the Environmental Protection Agency (EPA) to deny the petition submitted by the industry consortium Growth Energy to increase by 50 percent the allowable amount of ethanol in gasoline, from 10 percent in E10 fuel to 15 percent in the proposed E15 fuel.

Nationwide transition to E15 could damage vehicle emission control systems, decrease fuel economy, pose fire risks during transportation and retail, degrade water quality, worsen emissions of some air pollutants and escalate health risks for children and other vulnerable people, according to scientific studies by the Department of Energy, Department of Transportation Pipeline and Hazardous Materials Safety Administration, National Research Council, independent academic researchers and EPA scientists (DOE 2009a; DOT 2008; NRC 2008; U.S. EPA 2009a).

Moreover, EWG's review of Growth Energy's petition has identified numerous fundamental errors of fact and interpretation, both in its arguments advocating for ethanol increases and in its supporting data.

Notably, contrary to Growth Energy's claims, available data do not demonstrate that cars, other vehicles, and non-road engines burning ethanol in any amount over 10 percent would meet emission standards over the useful lives of these machines, as is required under the waiver provisions of the federal Clean Air Act, section 211(f)(4). Every scientific analysis invoked in Growth Energy's petition is misquoted, taken out of context, or otherwise misinterpreted in an attempt to argue for E15 compatibility with the current cars and equipment. In contrast to the petition claims, all reports cited by Growth Energy contain evidence that intermediate ethanol fuel blends are incompatible with the American vehicle fleet and with hundreds of millions of non-road engines.

Thus, the data cited in the petition not only fail to support the claims of the corn lobby, but also demonstrate that granting such a waiver would directly contradict the air quality protection principles laid out in the Clean Air Act.

Under the Clean Air Act, EPA has the authority to regulate fuels and fuel additives to protect public health from exposure to their emissions. According to the Clean Air Act's section 211(f)(4), any new fuel proposed for introduction into commerce that is not "substantially similar" to pre-existing fuels must receive a waiver contingent on the EPA Administrator's finding that "the applicant has established that such fuel or fuel additive or a specified concentration thereof, and the emission products of such fuel or fuel additive or a specified concentration thereof, will not cause or contribute to a failure of any emission control device or system (over the useful life of the motor vehicle, motor vehicle engine, nonroad engine or nonroad vehicle in which such device or system is used) to achieve compliance by the vehicle or engine with the emission standards."

To grant such a waiver, EPA "has required that applicants provide vehicle/engine testing for tailpipe emissions, evaporative emissions, materials compatibility, and driveability. Testing needs to include emissions over the full useful life of vehicle and equipment" (U.S. EPA 2009a).

Growth Energy has clearly failed to provide this required information in its petition for a waiver.

We have attached a detailed white paper, "Ethanol-Gasoline Fuel Blends May Cause Human Health Risks and Engine Issues," by EWG Senior Scientist Olga Naidenko, Ph.D. Dr. Naidenko summarizes the findings of peer-reviewed scientific literature relevant to the criteria the EPA must evaluate to determine the merits of the Growth Energy petition. This white paper provides the scientific and technical foundation for our response to that petition.

As summarized in this letter, the Growth Energy petition fails in the following critical respects:

  1. The Growth Energy petition is rife with misleading interpretations of the published scientific literature and ethanol fuel testing data.
  2. Most of the studies cited by Growth Energy in support of its petition suffer from serious scientific and technical weaknesses. Overall, these studies fail to provide the necessary vehicle and engine testing data needed to support a waiver from Clean Air Act provisions, thereby making it unlawful to increase concentrations of ethanol in blended fuels.
  3. There is compelling evidence that intermediate ethanol blends would cause engines, vehicles and equipment to fail to meet their emissions standards over their useful lives.
  4. Many studies show that transitioning the legacy vehicle fleet to intermediate ethanol-gasoline blends would increase emissions of multiple air pollutants, such as acetaldehyde and oxides of nitrogen, and would lead to higher levels of ozone and particle pollution.
  5. There is incontrovertible evidence from numerous authoritative sources that ethanol blends exceeding 10 percent damage small non-road engines and pose risks to operator safety.

The Growth Energy Petition Misinterprets Published Scientific Literature

An in-depth review of Growth Energy's petition by EWG scientists reveals numerous cases in which Growth Energy has asserted errors of fact and interpretation that have the effect of casting a favorable light on ethanol where it is not merited.

Examples of such errors of fact and interpretation include the following:

Claim: Growth Energy asserts that "extensive experience with use of ethanol-gasoline blends" (Growth Energy 2009, pg. 4) justifies its waiver request.

Fact: Widespread introduction of E10 fuels is relatively recent (post-2001) (DOE 2008a; DOE 2008b) and its full impact on engines, especially non-road engines, has not yet been evaluated. Moreover, the 1978 waiver for 10 percent ethanol in gasoline took place by statutory default, without comprehensive substantiation of the safety of E10, as required under the current review standards (U.S. EPA 2009a; U.S. EPA 2009c). As EPA recently stated, since E10 contains approximately 3.5 percent oxygen by weight, a gasoline-ethanol blend with 10 percent ethanol would not be deemed "substantially similar" to certification fuel under the current interpretation (U.S. EPA 2009a).

Claim: Growth Energy asserts that "E15 is similar in performance to E10" (Growth Energy 2009, pg. 5).

Fact: E15 is associated with further loss of fuel economy compared to E10. E15 would also result in higher acetaldehyde emissions from all engines and higher NOx emissions from non-road engines. These findings have been demonstrated by the DOE testing and by extensive experience with ethanol fuel blends around the world (Australian Government 2004; Bechtold 2007; DOE 2009a; Westerholm 2005).

Claim: Growth Energy asserts that "E15 will not cause or contribute to the failure of emission control devices or systems" (Growth Energy 2009, pg. 6) and that "Emissions control devices will meet current certified emissions standards with E15" (Growth Energy 2009, pg. 6).

Fact: E15 has been associated with increased catalyst temperature for 43% of vehicles tested (DOE 2009a), which would likely lead to early catalyst burnout and failure of emission control devices (Australian Government 2004; Drevna 2009).

Claim: Growth Energy asserts that "Long-term exhaust emissions testing (50,000-Mile durability testing) is not necessary for approval of the requested waiver" (Growth Energy, pg. 19-20).

Fact: EPA has clearly stated that as a condition for granting a waiver application, "testing needs to include emissions over the full useful life of vehicle and equipment" (U.S. EPA 2009b). Long-term testing is essential to ensure that the full useful life of the vehicle or equipment would not be adversely affected by E15. Already, car and equipment manufacturers and gasoline producers are very concerned about down-the-road problems with ethanol blends, including voiding of car and engine warranties (Drevna 2009; Jensen 2009b; Winston 2009). Presently, owner manuals for non-flex fuel vehicles explicitly state that the use of fuel above 10 percent ethanol may result in a denial of warranty claims (Drevna 2009; Jensen 2009b). Thus, premature approval of E15 in the absence of long-term testing may lead to confusion among vehicle owners, warranty litigations, and high economic costs.

Claim: Growth Energy asserts that the "Existing fuel dispensation infrastructure is capable of handling E15" (Growth Energy 2009, pg. 7).

Fact: The current fuel distribution system via pipelines is unsuitable for distribution of ethanol fuels (DOE 2009b; EIA 2002; USDA 2007). As evaluated by EPA, many of the underground storage tanks and retail station dispensing equipment would require extensive modification to be able to handle above E10 blend (U.S. EPA 2009b). Distribution and dispensation of ethanol fuels above E10 would also pose a significant fire hazard that requires specialized training and custom-made fire-fighting foams and could involve significant economic costs (Associated Press 2008; DOT 2008; Jensen 2009c; Niles 2007; TRANSCAER 2009).

Claim: Growth Energy asserts that the "DOE study of E15 and E20 did not find any significant changes in vehicle tailpipe emissions or small non-road engine emissions" (Growth Energy 2009, pg. 14).

Fact: Both E15 and E20 are associated with a statistically significant increase in acetaldehyde emissions (DOE 2009a). E20 has been also associated with increased NOx emissions (Australian Government 2004; DOE 2009a).

Claim: Growth Energy asserts that "E-15 will not impair the materials used in fuel systems to the point that emissions are adversely affected" (Growth Energy 2009, pg. 27).

Fact: E15 has never been tested for materials compatibility. Significant materials compatibility problems were found for E20 in both the Australian Government (2004) study and the Minnesota study cited in the petition (Minnesota Department of Agriculture 2008). Furthermore, the Minnesota study did not test the link between materials compatibility and emissions and thus it cannot be used to establish this claim.

Studies Cited by Growth Energy are Flawed and Insufficient

In support of its request for a waiver, Growth Energy cites 7 studies that, according to the authors, support the safety of E15 for the nation's vehicle fleet and non-road engines and "collectively demonstrate that use of E-15 will not cause or contribute to the failure of any emission control deice or system to meet its certification emission standards" (Growth Energy 2009).

  • The Department of Energy 2009 study, Effects of Intermediate Ethanol Blends on Legacy Vehicles and Small Non-Road Engines, is the only cited report that directly tested the effect of E15 on vehicles and non-road engine equipment. However, only 16 vehicles were tested by DOE, a sample size called "too small" by one of the authors of the study (Jensen 2009a). Moreover, only a short-term study has been carried out so far; the effects of E15 on the full useful life of vehicles remain unknown.
  • The American Coalition for Ethanol (ACE) 2007 study, Optimal Ethanol Blend-Level Investigation, included only 4 vehicles and was focused on examining fuel economy impact of ethanol blends, not vehicle emissions. The study did not include measurements of acetaldehyde and formaldehyde, two key air pollutants increased due to ethanol in fuel. The study was funded by the ethanol industry and it has not been peer-reviewed.
  • The Minnesota Department of Agriculture 2008 study, E20: The Feasibility of 20 Percent Ethanol Blends by Volume as a Motor Fuel, detected serious materials compatibility problems for both E10 and E20, such as discoloration of metals and plastics, deterioration of some materials tested, and reduction in flow for a fuel pump. The study was funded by the industry and it has not been peer reviewed.
  • The Coordinating Research Council (CRC) 2006 study, Fuel permeation from automotive systems: E-0, E-6, E-10, E-20 and E-85, examined E0, E6, E10, and E20 fuels and found statistically significant increases in permeation for all tested ethanol-blended fuels. The Growth Energy waiver application misrepresents the findings of the CRC study as demonstrating insignificant evaporative emissions for E20 when, in fact, the study reported that evaporative emissions from all ethanol-containing fuels were higher than for gasoline.
  • The Rochester Institute of Technology 2008 study, Report to the US Senate on E20 Ethanol Research, is an unpublished report of an ongoing study; the emissions data are not publicly available. Nevertheless, the report indicates that half of the tested vehicles experienced increased NOx emissions.
  • The Minnesota Center for Automotive Research 1999 study, Use of Mid-range Ethanol/Gasoline Blends in Unmodified Passenger Cars and Light Duty Trucks (Bonnema 1999), is an outdated study that examined E10 and E30. The study has not been peer-reviewed and no actual emissions data are publicly available. But the authors noted that some emissions were higher when running on E30 and that some vehicles on the road cannot adjust to intermediate ethanol blend fuels.
  • The Westerholm et al. 2005 report, Blending of ethanol in gasoline for spark emissions engines, is a 110-page literature summary of the different nations' experience with ethanol-blended fuels. The researchers did not conduct actual testing of vehicles, equipment, or materials. There is a single experiment that examines E15 evaporation, carried out by AVL MTC, an industry consulting company. Moreover, the data from this experiment indicate that Reid Vapour Pressure rises sharply when ethanol is added to gasoline fuels and peaks at ethanol contents between 5 and 10 percent, indicating a potential problem for E10 fuels.

Higher Blends of Ethanol May Damage Emission Control Systems

A comprehensive review of the evidence regarding the potential impact of E15 on cars and non-road engines shows that higher blends of ethanol can degrade emission control systems and increase emissions of acetaldehyde, PM2.5 particulate air pollution, ground-level ozone and other toxic air pollutants.

In 2007 the Department of Energy's National Renewable Energy Laboratory (NREL) and Oak Ridge National Laboratory initiated a test program to evaluate the impact of E15 and E20 ethanol blends on legacy vehicles and small non-road engines (Bechtold 2007; DOE 2008a; DOE 2009a). The DOE data, together with the findings of an E20 study commissioned by the Australian government and published in 2004, concurred in reporting increased exhaust and catalyst temperatures associated with ethanol fuels blends, especially for older vehicles (Australian Government 2004; DOE 2009a).

Modern vehicles equipped with oxygen sensor-based, closed-loop control systems are calibrated to appropriately compensate for higher levels of oxygen in ethanol blends. Under open-loop conditions such as wide-open throttle, increased fuel ethanol content generally leads to leaner (less fuel-rich) operation. Many newer vehicles can adjust to ethanol-blend fuel in open-loop conditions by applying a procedure called long-term fuel trim (LFT). Modern engines are calibrated to apply the same type of fuel trim in open-loop as in closed-loop conditions to maintain a stable fuel/oxygen ratio. In contrast, older vehicles, as well as some recent models, cannot perform such adjustments to higher ethanol oxygen content in fuel under open-loop conditions, resulting in hotter exhaust.

In the DOE study, 7 out of 16 vehicles tested (43 percent), including two 2007 model-year vehicles, ran significantly leaner during wide-open throttle as ethanol content in the fuel increased (DOE 2009a). Vehicles that ran leaner during wide-open throttle compared to E0 baseline also experienced higher catalyst temperatures. Compared to E0, catalyst temperature was higher by ~10oC for E10, over 20oC higher for E15, and up to 35oC higher for E20. Increased catalyst temperatures would lead to accelerated long-term catalyst degradation, potentially causing significantly higher emissions of toxic air pollutants, the need for expensive, unplanned replacements that may fall outside of the original manufacturer's warranty, and a shorter useful life of a vehicle.

The catalyst burnout problem highlights the potentially wide spectrum of negative effects of ethanol fuels on cars that have not been specifically designed to run on ethanol blends (which effectively includes vehicles from model year 2003 and older) (DOE 2009a; U.S. EPA 2007c). As summarized in the 2007 DOE review Technical Issues Associated with the Use of Intermediate Ethanol Blends, multiple studies found materials compatibility issues with E20, evidence of fuel filter obstruction even with E10, and likely impacts on driveability (Bechtold 2007). The Australian study reported that "greater levels of wear were observed for engines run with E20 than for those run with gasoline… [which] can result in compromise of the combustion system and lead to poor engine operation with resultant higher pre-catalyst emissions and increased fuel consumption" (Australian Government 2004).

Widespread use of fuel with ethanol exceeding 10 percent could impact 100 million vehicles currently on the road that are potentially vulnerable to higher catalyst temperatures in wide-open throttle mode (American Lung Association 2009).

Higher Ethanol Blends are Linked to Increased Air Pollution

While oxygenated fuels have been promoted for their potential ability to decrease certain air toxics, multiple studies have reported higher emissions of the hazardous air pollutants acetaldehyde and formaldehyde linked to increased ethanol content in fuels (Ban-Weiss 2008; Black 1998; DOE 2008a; Grosjean 2002; Whitney 2007; Winebrake 2001).

Both acetaldehyde and formaldehyde are considered by EPA to be probable human carcinogens (U.S. EPA 2007). Formaldehyde is associated with respiratory tract irritation, chronic bronchitis, and airway inflammation (U.S. EPA 2007). Acetaldehyde is a strong respiratory irritant and toxicant especially dangerous for children and adults with asthma. As demonstrated by a recent study, acetaldehyde air pollution is already above the 10–6 cancer risk level at most sites nationally (McCarthy 2009). Further increase in acetaldehyde could lead to increased cancer incidence and wider prevalence of respiratory problems.

Current findings on the air pollution profile of ethanol fuel blends indicate that instead of providing better air quality, ethanol fuel would result in no measurable improvement. Its use would substitute one set of air pollutants for another, with the consequences of potentially worsening health impacts from air pollution overall (American Lung Association 2009; Hill 2009; Jacobson 2007; U.S. EPA 2009b):

  • Acetaldehyde emissions significantly increase for all ethanol blends (DOE 2009a; U.S. EPA 2009b) especially when vehicles are started in cold temperatures (Whitney 2007). In the DOE study, acetaldehyde emissions doubled from E0 to E10 and tripled from E0 to E15 (DOE 2009a).
  • Formaldehyde emissions consistently increase for all ethanol blends compared to E0 by approximately 20 percent. (DOE 2009a).
  • NOx emissions increased by 50-75 percent for non-road engines operated with E10 and E15 ethanol blends compared to E0 (DOE 2009a).
  • Ethanol emissions are twice as high for E15 as E10 (DOE 2009a). Ethanol is converted to acetaldehyde in the atmosphere such that ethanol emissions contribute to acetaldehyde pollution with all the concomitant health effects (U.S. EPA 2009b).

The DOE study demonstrated an average of 15 percent reduction of CO emissions for E10 compared to E0. However, no further CO reduction was observed with E15 (DOE 2009a). Moreover, extensive research and testing carried out by the California Environmental Protection Agency Air Resources Board indicates that there might be better alternatives than ethanol or other oxygenate additives for reducing vehicle emissions, including CO emissions (CARB 2008).

Ethanol Fuel Blends Damage Non-Road Engines

Hundreds of millions of non-road engines are used across the country, including leaf blowers and line trimmers, lawn mowers, boat motors, chain saws, jet skis, snowmobiles, generators, and small tractors.

Ethanol fuels may cause many small engines to emit more hazardous air pollutants and ozone generators such as hydrocarbons and nitrogen oxides (American Lung Association 2009; Sahu 2009). The DOE study noted that NOx emissions increased by 50-75 percent for small engines operated on E10 and E15 ethanol blends (DOE 2009a) compared to plain gasoline.

Moreover, as indicated by the growing body of data, operation of small engines on ethanol fuel blends would likely lead to both performance and safety problems. Unlike modern cars, small engines lack an oxygen sensor feedback control and are unable to compensate for higher oxygen content in ethanol-containing fuels. As a result, engines operate under "lean" or oxygen-rich conditions, which leads to engine overheating. Higher temperatures were detected for non-road engines operated on every level of ethanol in fuel (E10, E15 and E20) in the DOE study.

Using an inappropriate fuel mix would impact the longevity of the engine and pose a hazard to the person operating it (Drevna 2009; Holshouser 2009; Johnson 2008; Oregon State Marine Board 2009; Outdoor Power Equipment Institute (OPEI) 2009; Williams 2008; U.S. EPA 1995).

With its initial testing of a small sample of currently sold non-road engines, the DOE study identified serious risks to the engine user (DOE 2009a). Three handheld trimmers demonstrated faster idle speed and experienced unintentional clutch engagement when operated on E15 and E20 (DOE 2009b). Small engines also experienced "missing" and "stalling" during operation on ethanol blends. Similar problems could occur in chainsaws, posing a risk to limb and life of the operator. As DOE reported, "small engines such as those in lawn mowers and lawn tractors, generators, line trimmers, chainsaws, and other similar equipment are open-loop engines, in that exhaust-sensing feedback is not used to control the fueling rate. Open-loop engines are commonly air-cooled and customarily operate in the fuel-rich regime to achieve cooler combustion temperatures. With a fixed fueling calibration, [increased ethanol content leads] to a higher combustion temperature and hence higher component temperatures" (DOE 2009a).

This theoretical analysis was borne out by findings that small engine exhaust temperatures rose between 10°C and 50°C from E0 to E15 blend fuel and between 20°C and 70°C from E0 to E20 blend fuel (DOE 2008a). These problems occurred for all levels of ethanol tested.

More Testing Is Needed

The data currently available on the effects of ethanol blends indicate a potential for severe effects on human and environmental health. Comprehensive assessment of ethanol fuel impact on air quality should consider air emissions from all stages of fuel production, transportation, and combustion. In addition, more testing is required to determine fuel compatibility with the current vehicle fleet, such as effects on catalyst durability, materials compatibility and driveability.

A DOE report has pointed out that "the U.S. legacy fleet is too diverse to predict E15/E20 impacts from the limited available data" (Bechtold 2007).

Until we have much more extensive scientific data and analysis, consumer safety, public health, and environmental protection may be at risk from premature adoption of mid-level ethanol blends. In light of the significant gaps in information to substantiate the safety of ethanol in fuel at levels exceeding 10 percent, EWG urges EPA to deny this waiver and uphold the Clean Air Act provisions designed to protect human health and the environment.


Olga V. Naidenko, Ph.D., Senior Scientist
Jane Houlihan, MSCE, Vice President for Research
Environmental Working Group
1436 U street, NW, Suite 100
Washington, DC 20009


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