Document ID: EPA-HQ-OAR-2011-0135-2974
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2013-05-20T04:00Z

EPA does not agree to delete the last two (of three total) paragraphs discussing the health effects associated with exposure to ethanol, and does not agree this language is "speculative," as OMB claims.  This language is consistent with EPA's previous statements about relevant available information on ethanol health effects (e.g., the 2010 RFS2 rule).  As we have indicated in previous discussions, we have included this information because the ingestion literature is critical to understand the health endpoints of potential interest, and which populations may be most susceptible. Because health effects of ethanol are determined primarily by its concentration in the target tissue, and tissue concentrations associated with adverse health effects are achievable by both the oral and inhalation routes, the literature on the effects of oral ethanol are essential to inform decisions about the health consequences of inhaled ethanol. As we indicate in the RIA, EPA is developing and evaluating pharmacokinetic models as tools to compare quantitatively the tissue concentrations achieved by oral and inhaled ethanol, and thus assess the health impacts of inhaled ethanol based on the extensive oral literature.  These models also enable extrapolating doses and effects across species (animal to human)  to better characterize the health hazards and dose-response relationships for low levels of ethanol exposure in the environment.  
For the reasons articulated above, the EPA believes its summary of the available science on ethanol health effects is objective, balanced and transparent.  The Agency also believes there is no scientific reason for changing our description of the current state of science. We have used this language consistently, whether we are talking about potential ethanol emission increases, as in the RFS2 rule, or decreases, as is the case with Tier 3.  The language makes it clear that literature on inhalation exposure is limited, and that the Agency is evaluating the relevance of observed health effects to low level exposures in the environment.  

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Tier 3 RIA Health Effects Text on Ethanol
EPA is planning to develop an assessment of the health effects of exposure to ethanol, a compound which is not currently listed on EPA's IRIS database.  Extensive health effects data are available for ingestion of ethanol, while data on inhalation exposure effects are sparse.  In developing the assessment, EPA is evaluating pharmacokinetic models as a means of extrapolating across species (animal to human) and across exposure routes (oral to inhalation) to better characterize the health hazards and dose-response relationships for low levels of ethanol exposure in the environment.
The IARC has classified "alcoholic beverages" as carcinogenic to humans based on sufficient evidence that malignant tumors of the oral cavity, pharynx, larynx, esophagus, and liver are causally related to the consumption of alcoholic beverages.  The U.S. DHHS in the 12[th] Report on Carcinogens also identified "alcoholic beverages" as a known human carcinogen (they have not evaluated the cancer risks specifically from exposure to ethanol), with evidence for cancer of the mouth, pharynx, larynx, esophagus, liver and breast.  There are no studies reporting carcinogenic effects from inhalation of ethanol.  EPA is currently evaluating the available human and animal cancer data to identify which cancer type(s) are the most relevant to a human health assessment of low-level oral and inhalation exposure to ethanol.
Noncancer health effects data are available from animal studies as well as epidemiology studies.  The epidemiologic data were obtained from studies of alcoholic beverage consumption.  Reported effects included neurological impairment, developmental effects, cardiovascular effects, immune system depression, and effects on the liver, pancreas and reproductive system.  There is evidence that children prenatally exposed via maternal ingestion of alcoholic beverages during pregnancy are at increased risk of hyperactivity and attention deficits, impaired motor coordination, a lack of regulation of social behavior or poor psychosocial functioning, and deficits in cognition, mathematical ability, verbal fluency, and spatial memory.,,,,,,,  Genetic factors influencing ethanol metabolism may render certain subpopulations more susceptible to the health effects of ethanol exposure by altering internal levels of ethanol and/or its metabolites (e.g., acetaldehyde).