97-11902. Ethylene Glycol; Toxic Chemical Release Reporting; Community Right-to-Know  

  • [Federal Register Volume 62, Number 88 (Wednesday, May 7, 1997)]
    [Notices]
    [Pages 24919-24924]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 97-11902]
    
    
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    ENVIRONMENTAL PROTECTION AGENCY
    
    [OPPTS-400110; FRL-5598-8]
    
    
    Ethylene Glycol; Toxic Chemical Release Reporting; Community 
    Right-to-Know
    
    AGENCY: Environmental Protection Agency (EPA).
    
    ACTION: Notice.
    
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    SUMMARY: EPA is issuing the results of its technical review and 
    evaluation of a petition to delete ethylene glycol from the list of 
    toxic chemicals subject to the reporting requirements under section 313 
    of the Emergency Planning and
    
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    Community Right-to-Know Act (EPCRA) and section 6607 of the Pollution 
    Prevention Act of 1990 (PPA). Since the petition to delete ethylene 
    glycol was withdrawn on October 28, 1996, there is no need for final 
    action by the Agency. However, the Agency has decided to issue its 
    findings in order to make publicly available the technical review and 
    subsequent scientific conclusion.
    
    FOR FURTHER INFORMATION CONTACT: Daniel R. Bushman, Acting Petitions 
    Coordinator, 202-260-3882 or e-mail: bushman.daniel@epamail.epa.gov, 
    for specific information regarding this document. For further 
    information on EPCRA section 313, contact the Emergency Planning and 
    Community Right-to-Know Information Hotline, Environmental Protection 
    Agency, Mail Stop 5101, 401 M St., SW., Washington, DC 20460, Toll 
    free: 1-800-535-0202, in Virginia and Alaska: 703-412-9877, or Toll 
    free TDD: 1-800-553-7672.
    
    SUPPLEMENTARY INFORMATION:
    
    I. Introduction
    
        Section 313 of the Emergency Planning and Community Right-to-Know 
    Act (EPCRA) requires certain facilities manufacturing, processing, or 
    otherwise using listed toxic chemicals in amounts above reporting 
    threshold levels, to report their environmental releases of such 
    chemicals annually. Beginning with the 1991 reporting year, such 
    facilities also must report pollution prevention and recycling data for 
    such chemicals, pursuant to section 6607 of the Pollution Prevention 
    Act of 1990 (PPA), 42 U.S.C. 13106. Section 313 established an initial 
    list of toxic chemicals that was comprised of more than 300 chemicals 
    and 20 chemical categories. Ethylene glycol was included on the initial 
    EPCRA section 313 list of toxic chemicals. Section 313(d) authorizes 
    EPA to add or delete chemicals from the list, and sets forth criteria 
    for these actions. EPA has added and deleted chemicals from the 
    original statutory list. Under section 313(e)(1), any person may 
    petition EPA to add chemicals to or delete chemicals from the list. 
    Pursuant to EPCRA section 313(e)(1), EPA must respond to petitions 
    within 180 days, either by initiating a rulemaking or by publishing an 
    explanation of why the petition is denied.
        EPCRA section 313(d)(2) states that a chemical may be listed if any 
    of the listing criteria are met. Therefore, in order to add a chemical, 
    EPA must demonstrate that at least one criterion is met, but does not 
    need to examine whether all other criteria are also met. Conversely, in 
    order to remove a chemical from the list, EPA must demonstrate that 
    none of the criteria are met.
        EPA issued a statement of petition policy and guidance in the 
    Federal Register of February 4, 1987 (52 FR 3479), to provide guidance 
    regarding the recommended content and format for submitting petitions. 
    On May 23, 1991 (56 FR 23703), EPA issued guidance regarding the 
    recommended content of petitions to delete individual members of the 
    section 313 metal compound categories. EPA has also published a 
    statement clarifying its interpretation of the section 313(d)(2) 
    criteria for adding and deleting chemical substances from the section 
    313 list (59 FR 61432, November 30, 1994) (FRL-4922-2).
    
    II. Description of the Petition
    
        On March 21, 1994, Bonded Products, Inc. petitioned the Agency to 
    delist ethylene glycol from the list of toxic chemicals subject to 
    reporting under section 313 of EPCRA and section 6607 of PPA. The 
    Bonded Products petition was based on the contention that: ethylene 
    glycol is biodegradable, rapidly loses its toxicity and, therefore, is 
    not expected to cause adverse environmental, or acute or chronic health 
    effects; and, that releases from the consumer use of ethylene glycol 
    are likely to be significantly higher compared to releases from 
    manufacturing facilities. The petitioners argued that ethylene glycol 
    does not meet any of the EPCRA section 313(d)(2) criteria for listing. 
    EPA staff reviewed the petition based on information and data that the 
    Agency retrieved from its own review of the literature, as well as 
    information supplied by other interested parties. On October 28, 1996, 
    Bonded Products withdrew their petition.
        The review of Bonded Products, Inc.'s petition was complete prior 
    to their request for withdrawal, and the Agency has determined that it 
    is in the public's best interest and clearly in keeping with the 
    Community-Right-to-Know ethic to provide a summary of the chemical 
    review and conclusion. Bonded Products, Inc. or any other party may re-
    petition the Agency on ethylene glycol at any time. The Agency remains 
    open to receiving and reviewing new information and re-evaluating its 
    position on this chemical as it relates to section 313 of EPCRA.
    
    III. Technical Review of Ethylene Glycol
    
        The technical review of the petition to delete ethylene glycol from 
    the EPCRA section 313 list of toxic chemicals included an analysis of 
    the relevant chemistry, metabolism and absorption, toxicity, and 
    exposure data available to the Agency for ethylene glycol. Summaries of 
    the analysis of each of these areas is provided in Units III.A. through 
    III.F. of this preamble, and a more complete discussion of this 
    information can be found in the EPA documents prepared for this 
    assessment (Refs. 1-14), which have been placed in the public docket 
    for this petition (Docket OPPTS-400110).
    
    A. Chemistry, Use, and Production Profile
    
        Ethylene glycol is a colorless, odorless, syrupy liquid with a 
    sweet taste. It has a relatively high boiling point (197.6  deg.C), 
    flash point (116  deg.C), autoignition temperature (412.93  deg.C), and 
    is relatively non-volatile at room temperature (Ref. 1). Ethylene 
    glycol absorbs water and can take up twice its weight of water at 100 
    percent relative humidity. Additionally, the substance reduces the 
    freezing point of water and is widely used as an antifreeze and deicer.
        Ethylene glycol is generally produced by the noncatalytic, liquid 
    phase hydration of ethylene oxide (Ref. 1). Diethylene glycol, 
    triethylene glycol and tetraethylene glycol are co-products. Other 
    processes have been patented such as: (1) oxidation of ethylene in an 
    aqueous medium using an iron-copper catalyst; and (2) rhodium-catalyzed 
    production of ethylene glycol from synthesis gas (a mixture of carbon 
    monoxide and hydrogen from coal gasification) instead of ethylene.
        There were 2.3 billion kilograms of ethylene glycol produced in 
    1992 and production has been fairly steady since the early 1980's (Ref. 
    2). Domestic consumption was 2.1 billion kilograms. The major end use 
    of ethylene glycol is in the production of polyethylene terephthalate 
    (PET), with 30 percent used for fibers and 22 percent used for films, 
    bottles, and other molded plastics, laminates, and castings (Ref. 2). 
    An additional 38 percent of ethylene glycol production is used in 
    antifreeze application, such as the principle ingredient of all-weather 
    automobile cooling system fluids, deicing solutions for aircraft and 
    pavement, and in fire extinguishers and sprinkler systems. The 
    remaining 10 percent of demand is in miscellaneous applications such as 
    a diluent and coupler in cutting fluids, as a solvent or coupling agent 
    for stains, dyes, resins, inks, soluble oils, and hydraulic fluids. It 
    is also used as a component in the manufacture of polyester laminating 
    resins and other plastics.
    
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    B. Metabolism and Absorption
    
        Ethylene glycol itself appears to have relatively low toxicity, but 
    it is oxidized to a variety of more toxic metabolites such as 
    glycolaldehyde, glycolic acid, glyoxalic acid and oxalic acid (Ref. 6). 
    In general, the accumulation of these acids leads to acidosis (the 
    state that is characterized by actual or relative decrease of alkali in 
    body fluids in relation to the acid content). Present information 
    suggests that glycolic acid is the major toxic metabolite contributing 
    to metabolic acidosis, which is the underlying cause of systemic 
    toxicity following exposure to ethylene glycol.
        Based on a comparison of metabolism studies, ethylene glycol 
    appears to be less well absorbed following dermal application than 
    following administration via oral gavage (Ref. 10). In addition, even 
    when an ethylene glycol aerosol is generated to maximize the amount 
    available for inhalation, the body burden remains fairly low. In the 
    study by Frantz et al. (Ref. 15), ethylene glycol and its metabolites 
    (glycolic acid and oxalic acid) were excreted in the urine of animals 
    dosed both orally and dermally. In contrast, the study by Marshall and 
    Cheng (Ref. 16) showed that after inhalation exposure to 
    14C-labeled ethylene glycol, the only 14C-
    containing material identified in the plasma and urine (both for the 
    aerosol and vapor) was unmetabolized ethylene glycol.
    
    C. Human Toxicity Evaluation
    
        The inherent toxicity of ethylene glycol is low relative to several 
    of its metabolites. The evidence for this comes from clinical studies 
    and laboratory investigations (Ref. 4). Ethanol is a competitive 
    inhibitor of alcohol dehydrogenase (ADH), the first enzyme in the 
    ethylene glycol metabolic pathway, and is very effective in treating 
    animal and human ethylene glycol poisonings. If treatment is started 
    early enough, the metabolic acidosis and renal failure discussed below 
    can be prevented.
        1. Inhalation toxicity. Two inhalation developmental toxicity 
    studies have been conducted by the same group (Refs. 17 and 18). In a 
    whole body exposure study (Ref. 17), mice and rats were exposed to 
    ethylene glycol aerosols of 150, 1,000 or 2,500 milligrams per cubic 
    meter (mg/m3) for 6 hours/day on gestational days 6 through 
    15. The actual measured concentrations were 119, 888, or 2,090 mg/
    m3. In rats, maternal toxicity occurred only at the highest 
    concentration and was indicated by a significant increase in absolute 
    and relative liver weight. In rats, evidence of prenatal developmental 
    toxicity (reduced ossification in the humerus, zygomatic arch, and the 
    metatarsals and proximal phalanges of the hindlimb) was observed at the 
    two higher concentrations. In mice, incidences of prenatal 
    developmental toxicity were increased at the two highest concentrations 
    and included malformations in the head (exencephaly), face (cleft 
    palate, foreshortened and abnormal face, and abnormal facial bones), 
    and skeleton (vertebral fusions, and fused, forked, and missing ribs). 
    The No Observed Adverse Effect Level (NOAEL) for maternal toxicity in 
    rats was 888 mg/m3 and in mice was 119 mg/m3. The 
    NOAEL for developmental toxicity in rats was 119 mg/m3 and 
    in mice was below this concentration.
        A major confounding factor in this study was the deposition of a 
    detectable quantity of ethylene glycol upon the animals during 
    exposure. The animals could have received the chemical via the oral 
    route by preening or by dermal absorption, although much less would be 
    taken in via the skin. Analysis of the chemical on the fur of rats and 
    mice after the exposure period at the highest concentration indicated 
    that much of the chemical dose (65-95 percent) was potentially derived 
    from ingestion after grooming.
        To address the potential confounding factor of multiple exposure 
    routes cited above, a further study used nose-only exposure of mice to 
    500, 1,000, and 2,500 mg/m3 of ethylene glycol aerosol for 6 
    hours/day on gestational days 6 through 15 (Ref. 18). Results from the 
    positive control (whole body exposure to 2,100 mg/m3) 
    confirmed the results from the previous study. In the nose-only 
    portion, the two higher concentrations produced increased kidney 
    weights in the dams. At the highest concentration, fetal weights were 
    reduced and fetal skeletal variations and one fetal skeletal 
    malformation (fused ribs) were increased. The developmental NOAEL for 
    nose-only inhalation exposure was 1,000 mg/m3; the maternal 
    NOAEL was 500 mg/m3. The developmental NOAEL in this study 
    was at least 10 times the whole body value since a NOAEL was not 
    established in the previous whole body inhalation study but was less 
    than 119 mg/m3. The maternal NOAEL was approximately five 
    times the previous value. This nose-only exposure study indicates that 
    most of the adverse effects seen in the whole-body exposure study were 
    due to systemic exposure from noninhalation routes; however, as 
    discussed above, adverse effects were seen in the nose-only exposure 
    study.
        The toxicity data strongly indicate that ethylene glycol is much 
    less toxic than its metabolites; however, it is not known if ethylene 
    glycol might act directly on embryos. The available literature does not 
    provide adequate data to allow definitive conclusions concerning 
    ethylene glycol's toxicity to embryos (Ref. 4).
        2. Oral toxicity. Ethylene glycol is expected to be absorbed 
    through the skin and from the lung and the gastrointestinal tract. 
    After absorption, it is expected to enzymatically oxidize to oxalic 
    acid, glycolic acid, glycolaldehyde and carbon dioxide. The aldehyde 
    metabolites are believed to be responsible for neurotoxicity and the 
    oxalic acid metabolites for renal toxicity (Ref. 8).
        a. Renal toxicity. The oral reference dose (RfD) for ethylene 
    glycol as established by the Agency's RfD/RfC (reference concentration) 
    working group is 2 milligrams per kilogram per day (mg/kg/day). An RfD 
    reflects the Agency's estimate of a level of daily exposure to the 
    human population (including sensitive subgroups) that is likely to be 
    without an appreciable risk of deleterious effects during a lifetime 
    (Ref. 19). The RfD for ethylene glycol is based on a feeding study by 
    DePass et al. (1986, as cited in EPA's Integrated Risk Information 
    System (IRIS), 1994; Ref. 20) in which the critical effect was kidney 
    toxicity. Groups of male and female rats (30/sex/group) and male and 
    female mice (20/sex/group) were fed diets containing ethylene glycol at 
    doses of 0, 40, 200, or 1,000 mg/kg/day for 2 years. Urinary calcium 
    oxalate crystals and increased kidney weight were seen in all high-dose 
    rats. Histopathologic changes in high-dose male rats included tubular 
    cell hyperplasia, tubular dilation, peritubular nephritis, parathyroid 
    hyperplasia, and generalized soft tissue mineralization. No adverse 
    effects were seen in rats of either sex at the mid or the low doses. 
    There were no adverse effects seen in mice of either sex at any dose 
    tested. The Lowest Observed Adverse Effect Level (LOAEL) was determined 
    to be 1,000 mg/kg/day and the NOAEL was 200 mg/kg/day. The RfD was set 
    with an uncertainty factor of 100, 10 for interspecies extrapolation 
    and 10 for differences in human sensitivity. Confidence in the study, 
    the uncertainty factor and the RfD was high.
        b. Developmental/reproductive toxicity. IRIS includes a review of 
    several developmental reproductive studies with LOAELs at or near that 
    seen in the DePass study which was
    
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    used to set the oral RfD. These studies were not chosen as the basis 
    for the RfD since the LOAEL from the DePass study was somewhat lower 
    and the RfD was deemed protective of developmental effects. In a 3-
    generation reproduction study, Lamb, as cited in IRIS (Ref. 20), 
    treated rats with 0, 40, 200, or 1,000 milligrams per kilogram (mg/kg) 
    in the diet and found no treatment related effects. In another study 
    cited in IRIS (Ref. 20), ethylene glycol was administered by gavage at 
    0, 50, 150, 500 or 1,500 mg/kg to 30 pregnant female CD-1 mice/group on 
    gestation days 6-15. Animals were sacrificed on gestation day 18 and 
    examined for signs of maternal and developmental toxicity. There was an 
    increase in skeletal abnormalities at both 500, and 1,500 mg/kg. A No 
    Observed Effect Level (NOEL) was established at 150 mg/kg for 
    developmental toxicity with a Lowest Observed Effect Level (LOEL) of 
    500 mg/kg.
        c. Oncogenicity/carcinogenicity/mutagenicity. There is no evidence 
    that ethylene glycol is oncogenic or that it is a mutagen (Ref. 8).
        d. Acute toxicity. Ethylene glycol is acutely toxic to humans; the 
    minimum lethal ingested dose for adults is approximately 1.4 
    milliliters per kilogram (ml/kg) or 100 ml for a 70 kg person (Ref. 8). 
    Signs of ethylene glycol poisoning can be divided into three stages. 
    Stage one includes central nervous system (CNS) disturbances and 
    gastrointestinal symptoms. Stage two includes signs of cardiovascular, 
    pulmonary, and metabolic irregularities and stage three includes renal 
    failure brought on by the precipitation of calcium oxalate crystals in 
    renal tubules and from the direct toxic action of oxalic and glycolic 
    acids upon the kidneys (Ref. 8).
    
    D. Environmental Toxicity
    
        Ethylene glycol appears to represent a low hazard to the 
    environment (Refs. 8 and 11). The freshwater aquatic toxicity data 
    range from a median effective concentration (EC50) of 4.4 
    grams per milliliter (g/ml) (duckweed) to a median lethal concentration 
    (LC50) of 111 g/ml (bluegill sunfish). Terrestrial toxicity 
    data range from a median lethal dose (LD50) of 1.65 grams 
    per kilogram (g/kg) for cats to 5.5 g/kg for dogs and 12 g/kg for mice.
        Reports of animal poisonings that were reviewed, were the results 
    of accidental or intentional releases during consumer use. They were 
    not the result of environmental exposures that may result from releases 
    of ethylene glycol that are reasonably likely to come from TRI 
    reporting facilities under normal operating conditions.
    
    E. Exposure Assessment
    
        Ethylene glycol can be acutely toxic to humans. Therefore, an 
    assessment was conducted of the potential for adverse acute human 
    health effects to occur as a result of concentrations of ethylene 
    glycol that are reasonably likely to exist beyond facility site 
    boundaries as a result of continuous, or frequently recurring, releases 
    from facility sites (Refs. 5, 6, and 13). As discussed above in Unit 
    III.C. of this preamble, ethylene glycol produces adverse chronic 
    health effects only at relatively high doses and thus has low chronic 
    toxicity. Therefore, an exposure assessment was also conducted for 
    chronic health effects (Refs. 5, 6, and 21). For a discussion of the 
    use of exposure in EPCRA section 313 listing/delisting decisions, refer 
    to the Federal Register of November 30, 1994.
        Ethylene glycol releases reported for 1992 were retrieved from the 
    Toxic Release Inventory System (TRIS) data base. The TRIAIR model, the 
    Office of Pollution Prevention and Toxics' (OPPT) program for assessing 
    releases of TRI chemicals to the atmosphere, was used to estimate 
    chronic concentrations and exposures resulting from releases of 
    ethylene glycol. The Point Plume (PTPLU) model was used to derive 
    estimates of acute concentrations and exposures resulting from 
    atmospheric releases. The TRIAIR model assumes a 99.9 percent 
    destruction efficiency for all releases that are reported as sent to 
    incinerations. A half-life of 22.6 hours in the atmosphere was used for 
    ethylene glycol in the assessment. Ethylene glycol is quite 
    biodegradable, but is not readily sorbed, volatilized, or hydrolyzed 
    (Ref. 6).
        According to the 1992 releases obtained from TRIS, over 11.7 
    million pounds of ethylene glycol are released per year by about 940 
    facilities nationwide. Data from the Aerometric Information Retrieval 
    System (AIRS) Facility Subsystem were also considered. Based on review 
    of AIRS and the type of data available for ethylene glycol, it was 
    determined that the data for ethylene glycol are not adequate to 
    support an exposure assessment.
        Eighteen states each discharging over 100,000 pounds per year 
    accounted for 93 percent of the total reported releases of ethylene 
    glycol to the atmosphere. These releases were used for chronic exposure 
    estimations. Each of the highest per-site discharges were used to 
    estimate concentrations and exposures under acute conditions.
        Concentrations modeled with the PTPLU model can be expected to 
    occur up to 250 meters from the source, which may be beyond the 
    facility fenceline. The PTPLU model provides ground-level 
    concentrations which are hourly average values. Incorporating wind 
    conditions, three scenarios were generated: (1) The typical situation; 
    (2) the stagnation situation; and (3) the maximum situation. The 
    maximum scenario is anticipate to last for only 2 hours, as compared 
    with the 24-hour duration of the typical and stagnation scenarios. As 
    the name implies, the stagnation scenario incorporates relatively 
    little air movement. Each scenario was run for stack releases and for 
    fugitive releases. Assumptions made were conservative on the whole. 
    However, the assumption that releases occur over 365 days and 24 hours 
    a day is not conservative. If, for example, releases occurred over only 
    1 month, even with 24-hour a day discharge, the resulting exposure 
    estimates would increase by a factor of 12 or one order of magnitude.
    
    F. Exposure Evaluation
    
        1. Chronic inhalation exposure. In evaluating chronic inhalation 
    exposures, ideally, exposure estimates would be compared to an RfC. 
    However, in this case chronic inhalation information is neither readily 
    available nor abundant, so an RfC has not been derived for ethylene 
    glycol. In general, the oral RfD should not be used to evaluate 
    inhalation exposures to ethylene glycol because it appears that the 
    metabolism via the two routes is different. Specifically, this is 
    demonstrated by the lack of toxic metabolites of ethylene glycol found 
    in the urine and plasma of animals dosed via inhalation. Additionally, 
    it is believed that the proximate cause for the toxicity seen from 
    ethylene glycol is not attributed to the chemical itself but rather to 
    its metabolites. Therefore use of the oral RfD would tend to be overly 
    protective for inhalation effects from exposure to ethylene glycol. If, 
    however, the evaluation of the chronic exposure data indicates that 
    concentrations are below the RfD value, then the likelihood of 
    concentrations of concern existing for inhalation effects is greatly 
    diminished. For these reasons, the chronic exposures predicted were 
    compared to the oral RfD of 2 mg/kg/day. The comparison showed that 
    even the highest chronic exposures predicted for the chemical are, at a 
    minimum, an order of magnitude below the RfD. Therefore, it is not 
    predicted that concentrations of concern will exist for chronic 
    inhalation exposures to ethylene glycol as a result
    
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    of releases from TRI reporting facilities (Ref. 6).
        2. Acute inhalation exposure. Although the oral RfD was used to 
    assess chronic inhalation exposures it was not used to assess acute 
    inhalation exposures. This is because oral RfDs are based on the 
    assumption of lifetime exposure (i.e., long-term exposure) and in most 
    cases are not appropriately applied to less-than-lifetime exposure 
    situations such as acute inhalation exposures. In addition, as 
    discussed above, it appears that ethylene glycol metabolism is 
    different via the oral and inhalation routes of exposure. Therefore, 
    instead of using the RfD, the acute inhalation assessment focused on 
    the generation of Margin of Exposure (MOE) calculations for inhalation 
    exposures. A MOE calculation is used in instances of non-cancer 
    endpoints and is essentially a ratio of the NOAEL or LOAEL and the 
    estimated exposure to the particular chemical, including any modifying 
    factors on the exposure (absorption, etc.). The resultant value is then 
    compared to the product of the uncertainty factors which are selected 
    for the chemical of interest. Uncertainty factors are generally factors 
    of 10 with each factor representing a specific area of uncertainty in 
    the available data. For ethylene glycol, a factor of 10 was introduced 
    to account for the possible differences in responsiveness between 
    humans and animals in prolonged exposure studies and a second factor of 
    10 was used to account for variation in susceptibility among 
    individuals in the human population. The resultant uncertainty factor 
    of 100 was therefore used in this assessment. This assessment focused 
    on maternal and developmental toxicity, which EPA believes are the most 
    significant adverse chronic effects caused by ethylene glycol. For the 
    generation of MOEs used in this assessment the NOAELs from the Tyl 
    study (Ref. 18) were utilized.
        MOEs calculated from estimated stack emissions were below the 
    relevant uncertainty factors for the top two releasers for all exposure 
    scenarios for maternal toxicity. For developmental toxicity, MOEs below 
    the relevant uncertainty factors were calculated for the stagnant and 
    maximum exposure scenarios. MOEs calculated from fugitive releases 
    under the stagnant condition were also below the relevant uncertainty 
    factors for the top five releasers for both maternal and developmental 
    toxicity. A similar situation was observed under the maximum scenario 
    for maternal toxicity. Two things should be noted about the calculated 
    MOEs. The first is that all exposure estimates were driven by facility 
    specific data reported as required under EPCRA section 313. These 
    estimates are considered within the realm of possibility, although are 
    characterized as ``what if'' scenarios. These ``what if'' scenarios 
    provide a possible exposure level, without probability and are not 
    based on bounding or worst-case conditions which fall outside the 
    exposure curve. Second, there is limited information to suggest that no 
    metabolites are formed when ethylene glycol is inhaled. Since the 
    toxicity data indicates that the metabolites of ethylene glycol are 
    much more toxic than ethylene glycol itself, this normally would 
    greatly reduce the concern for inhalation exposure to this chemical. 
    However, adverse effects were noted in the 1995 Tyl study (Ref. 18) 
    with nose-only exposure in rodents, which indicates that ethylene 
    glycol is toxic via the inhalation route of exposure. Therefore, the 
    resultant NOAELs from that study were utilized in this acute inhalation 
    exposure assessment. Further, 100 percent of the inhaled dose of 
    ethylene glycol is assumed to be absorbed.
        In summary, based on the concentrations likely to exist beyond 
    facility site boundaries and the resulting MOE calculations, there is a 
    potential for chronic maternal and developmental effects for the 
    general population following acute inhalation exposures to ethylene 
    glycol (Ref. 6).
        3. Acute and chronic oral exposures. The potential dose rates 
    predicted for surface water driven oral exposures are identified as 
    bounding estimates and are, therefore, likely to be much higher than 
    actual exposures. Using the highest potential dose rate identified in 
    the exposure assessment of 80 mg/day and dividing by 70 kg (standard 
    assumption for body weight), a modified dose of 1.143 mg/kg/day was 
    calculated. This dose is below the RfD of 2 mg/kg/day indicating that 
    the exposure estimated is not likely to be associated with adverse 
    chronic health risks (Refs. 6 and 21).
        None of the exposure data indicates that ethylene glycol will be 
    present beyond facility site boundaries at concentrations that can 
    reasonably be anticipated to cause the adverse acute human health 
    effects discussed under Unit III.C.2.d. of this preamble (Refs. 6 and 
    13). Therefore, it is unlikely that adverse acute human health effects 
    are reasonably likely to occur as a result of concentrations likely to 
    exist beyond facility site boundaries as a result of continuous, or 
    frequently recurring, releases of ethylene glycol.
    
    G. Summary of Technical Review
    
        The data indicate that, based on the doses required to cause 
    adverse effects, ethylene glycol has low chronic and acute toxicity to 
    humans both orally and by inhalation. The exposure analysis indicates 
    that ethylene glycol cannot reasonably be anticipated to cause 
    significant adverse acute human health effects at concentration levels 
    that are reasonably likely to exist beyond facility site boundaries as 
    a result of continuous, or frequently recurring, releases from facility 
    sites. The analysis of ethylene glycol's chronic toxicity concluded 
    that ethylene glycol can reasonably be anticipated to cause chronic 
    maternal and developmental effects in humans at relatively high doses. 
    It was also determined that concentrations of ethylene glycol that are 
    reasonably likely to exist beyond facility site boundaries as a result 
    of acute exposure scenarios are reasonably likely to be sufficient to 
    cause these chronic maternal and developmental effects. Based on 
    available literature, ethylene glycol represents a low hazard to the 
    environment and is not anticipated to cause environmental toxicity as a 
    result of reported releases of ethylene glycol from facility sites.
    
    IV. Explanation
    
        Since the petition to delete ethylene glycol has been withdrawn by 
    Bonded Products, Inc. EPA has no statutory responsibility to deny or 
    grant the initial request. However, because the technical review and 
    evaluation of the petition are complete, EPA determined that it is in 
    the public's best interest, and clearly in keeping with the Community 
    Right-to-Know ethic, to provide the public with a summary of EPA's 
    review and conclusion. Based on the technical review discussed above, 
    EPA concluded that this petition be denied based on concerns for 
    chronic maternal and developmental effects for the general population 
    following acute inhalation exposure from reported air releases of 
    ethylene glycol. EPA believes that ethylene glycol meets the toxicity 
    criteria of EPCRA section 313(d)(2)(B) based on the available chronic 
    maternal and developmental toxicity data and the exposure analysis.
    
    V. References
    
        1. USEPA, OPPT. Tou, Jenny; ``Chemistry Report on Ethylene Glycol, 
    EPCRA Section 313 Delisting Petition.'' (June 1, 1994).
        2. USEPA, OPPT. Krueger, Susan; ``Economic Analysis of the Proposed 
    Delisting of Ethylene Glycol from the
    
    [[Page 24924]]
    
    EPCRA Section 313 Toxic Release Inventory.'' (May 16, 1994).
        3. USEPA, OPPT. Memorandum from Pat Jennings, Exposure Assessment 
    Branch, Economics, Exposure, and Technology Division. Subject: Summary 
    of the Environmental Fate of Ethylene Glycol. (May 20, 1994).
        4. USEPA, OPPT. Memorandum from Mary Henry, Health Effects Branch, 
    Health and Environmental Review Division. Subject: Ethylene Glycol 
    Petition. (August 3, 1995).
        5. USEPA, OPPT. Memorandum from Patricia Harrigan, Exposure 
    Assessment Branch, Economics, Exposure, and Technology Division. 
    Subject: Expanded Exposure Assessment for Ethylene Glycol. (June 19, 
    1995).
        6. USEPA, OPPT. Memorandum from Linda M. Rusak, Hazard Integrator, 
    Analysis and Information Management Branch, Chemical Screening and Risk 
    Assessment Division. Subject: Petition to Delist Ethylene Glycol from 
    TRI. (September 6, 1995).
        7. USEPA, OPPT. Memorandum from Leonard C. Keifer, Chemist, Health 
    Effects Branch, Health and Environmental Review Division. Subject: 
    Metabolism of Ethylene Glycol. (March 29, 1995).
        8. USEPA, OPPT. Memorandum from Angela Auletta, Chief, Health 
    Effects Branch, Health and Environmental Review Division. Subject: 
    Petition to Delist Ethylene Glycol from the Toxic Chemical Release 
    Inventory. (May 23, 1994).
        9. USEPA, OPPT. Memorandum from Mary Henry, Health Effects Branch, 
    Health and Environmental Review Division. Subject: Review of 
    Developmental Toxicity Studies with Ethylene Glycol. (March 24, 1995).
        10. USEPA, OPPT. Memorandum from Leonard C. Keifer, Chemist, Health 
    Effects Branch, Health and Environmental Review Division. Subject: 
    Review of Absorption/Metabolism Study for Ethylene Glycol Administered 
    via Inhalation and Comparison with Results from Dosing via Oral Gavage 
    and Dermal Administration. (August 1, 1995).
        11. USEPA, OPPT. Memorandum from J. V. Nabholz, Health and 
    Environmental Review Division. Subject: Ethylene Glycol [107-21-1]: 
    Wildlife Poisoning. (December 5, 1995).
        12. USEPA, OPPT. Memorandum from Patricia Harrigan, Exposure 
    Assessment Branch, Economics, Exposure, and Technology Division. 
    Subject: Comparison of 1993 Releases of Ethylene Glycol. (August 24, 
    1995).
        13. USEPA, OPPT. Memorandum from Linda M. Rusak, Hazard Integrator, 
    Analysis and Information Management Branch, Chemical Screening and Risk 
    Assessment Division. Subject: Ethylene Glycol, Acute Risk Assessment. 
    (December 16, 1994).
        14. USEPA, ORD. Memorandum from Carole Kimmel, National Center for 
    Environmental Assessment. Subject: Review of Ethylene Glycol Risk 
    Assessment for EPCRA Section 313 Delisting Petition. (November 2, 
    1995).
        15. Frantz, S.W. et al., ``Ethylene Glycol: Comparison of 
    Pharmacokinetics and Material Balance Following Single Intravenous, 
    Oral and Cutaneous Administration to Male and Female Sprague-Dawley 
    Rats.'' Bushy Run Research Center, Export, PA. Project Report 51-543. 
    (March 24, 1989).
        16. Marshall, Thomas C. and Yung Sung Cheng. ``Deposition and Fate 
    of Inhaled Ethylene Glycol Vapor and Condensation Aerosol in the Rat.'' 
    Fundamental and Applied Toxicology. v. 3, (1983), pp. 175-181.
        17. Tyl, R.W. et al., ``Evaluation of the Developmental Toxicity of 
    Ethylene Glycol Aerosol in the CD Rat and CD-1 Mouse by Whole-Body 
    Exposure.'' Fundamental and Applied Toxicology. v. 24, (1995), pp. 57-
    75.
        18. Tyl R.W. et al., ``Evaluation of the Developmental Toxicity of 
    Ethylene Glycol Aerosol in CD-1 Mice by Nose-Only Exposure.'' 
    Fundamental and Applied Toxicology. v. 27, (1995), pp. 49-62.
        19. IRIS. 1994. ``Glossary of Risk Assessment-Related Terms.'' U.S. 
    Environmental Protection Agency's Integrated Risk Information System. 
    (February 1, 1994).
        20. IRIS. 1994. U.S. Environmental Protection Agency's Integrated 
    Risk Information System file pertaining to Ethylene Glycol. (March 8, 
    1994).
        21. USEPA, OPPT. Memorandum from Linda M. Rusak, Hazard Integrator, 
    Analysis and Information Branch, Chemical Screening and Risk Assessment 
    Division. Subject: Ethylene Glycol, Chronic Risk Assessment. (August 
    19, 1996).
    
    VI. Administrative Record
    
        The record supporting this notice is contained in docket control 
    number OPPTS-400110. All documents, including the references listed in 
    Unit V. above and an index of the docket, are available to the public 
    in the TSCA Non-Confidential Information Center (NCIC), also known as 
    the Public Docket Office, from noon to 4 p.m., Monday through Friday, 
    excluding legal holidays. The TSCA NCIC is located at EPA Headquarters, 
    Rm. NE-B607, 401 M St., SW., Washington, DC 20460.
    
    List of Subjects
    
        Environmental protection, Community right-to-know, Reporting and 
    recordkeeping requirements, and Toxic chemicals.
    
        Dated: April 28, 1997.
    Lynn R. Goldman,
    Assistant Administrator for Prevention, Pesticides and Toxic 
    Substances.
    
    [FR Doc. 97-11902 Filed 5-7-97; 8:45 am]
    BILLING CODE 6560-50-F
    
    
    

Document Information

Published:
05/07/1997
Department:
Environmental Protection Agency
Entry Type:
Notice
Action:
Notice.
Document Number:
97-11902
Pages:
24919-24924 (6 pages)
Docket Numbers:
OPPTS-400110, FRL-5598-8
PDF File:
97-11902.pdf