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    Concise International Chemical Assessment Document 22









    ETHYLENE GLYCOL: Environmental aspects











    This report contains the collective views of an international group of
    experts and does not necessarily represent the decisions or the stated
    policy of the United Nations Environment Programme, the International
    Labour Organisation, or the World Health Organization.


    First draft prepared by Dr Stuart Dobson, Institute of Terrestrial
    Ecology, Natural Environment Research Council, Huntingdon, United
    Kingdom




    Published under the joint sponsorship of the United Nations
    Environment Programme, the International Labour Organisation, and the
    World Health Organization, and produced within the framework of the
    Inter-Organization Programme for the Sound Management of Chemicals.



    World Health Organization
    Geneva, 2000



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    WHO Library Cataloguing-in-Publication Data

    Ethylene glycol : environmental aspects.

         (Concise international chemical assessment document ; 22)

         1.Ethylene glycol - toxicity 2.Risk assessment
         3.Environmental exposure
         I.International Programme on Chemical Safety II.Series

         ISBN 92 4 153022 7         (NLM Classification: QD 305.A4)
         ISSN 1020-6167

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    TABLE OF CONTENTS

       FOREWORD

    1. EXECUTIVE SUMMARY

    2. IDENTITY AND PHYSICAL/CHEMICAL PROPERTIES

    3. ANALYTICAL METHODS

    4. SOURCES OF ENVIRONMENTAL EXPOSURE

    5. ENVIRONMENTAL TRANSPORT, DISTRIBUTION, AND TRANSFORMATION

    6. ENVIRONMENTAL LEVELS

    7. EFFECTS ON ORGANISMS IN THE LABORATORY AND FIELD

       7.1. Aquatic organisms

           7.1.1. Toxicity of deicer formulations

           7.1.2. Field effects

       7.2. Terrestrial organisms

    8. EFFECTS EVALUATION

       8.1. Predicted environmental concentration

       8.2. Predicted no-effect concentration

       8.3. Environmental risk factors

    INTERNATIONAL CHEMICAL SAFETY CARD

    REFERENCES

    APPENDIX 1 -- SOURCE DOCUMENTS

    APPENDIX 2 -- CICAD PEER REVIEW

    APPENDIX 3 -- CICAD FINAL REVIEW BOARD

    RÉSUMÉ D'ORIENTATION

    RESUMEN DE ORIENTACION
    

    FOREWORD

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    1  International Programme on Chemical Safety (1994)
        Assessing human health risks of chemicals: deriviation of
        guidance values for health-based exposure limits. Geneva, World
       Health Organization (Environmental Health Criteria 170).

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    FIGURE 1


    1.  EXECUTIVE SUMMARY

         This CICAD on the environmental aspects of ethylene glycol was
    prepared by the Institute of Terrestrial Ecology, United Kingdom,
    based on the report  Environmental hazard assessment: Ethylene glycol
    (Nielsen et al., 1993). The report on ethylene glycol prepared by the
    German Chemical Society Advisory Committee on Existing Chemicals of
    Environmental Relevance (BUA, 1991) was also used as a source
    document. In addition to these documents, a search of recent
    literature was conducted up to 1998. Information on the nature of the
    peer review process for the main source documents is presented in
    Appendix 1. Information on the peer review of this CICAD is presented
    in Appendix 2. This CICAD was approved as an international assessment
    at a meeting of the Final Review Board, held in Washington, DC, USA,
    on 8-11 December 1998. Participants at the Final Review Board meeting
    are listed in Appendix 3. The International Chemical Safety Card (ICSC
    0270) produced by the International Programme on Chemical Safety
    (IPCS, 1993) has also been reproduced in this document.

         Ethylene glycol (CAS No. 107-21-1) is a clear, colourless, syrupy
    liquid with a sweet taste but no odour. It has low volatility. It is
    miscible with water and some other solvents, slightly soluble in
    ether, but practically insoluble in benzene, chlorinated hydrocarbons,
    petroleum ethers, and oils. The log octanol/water partition
    coefficient is -1.93 to -1.36.

         Estimated world production capacity was 9.4 million tonnes in
    1993. Release to the environment is mainly to the hydrosphere. The
    largest local release to surface waters would follow ethylene glycol's
    use as a deicer on airport runways and planes. On a worldwide basis,
    approximately two-thirds of ethylene glycol is used as a chemical
    intermediate, with a further one-quarter used as an antifreeze in
    engine coolants.

         Ethylene glycol released to the atmosphere will be degraded by
    reaction with hydroxyl radicals; the half-life for the compound in
    this reaction has been estimated at between 0.3 and 3.5 days.

         No hydrolysis of ethylene glycol is expected in surface waters.

         The compound has little or no capacity to bind to particulates
    and will be mobile in soil. 

         The low octanol/water partition coefficient and measured
    bioconcentration factors in a few organisms indicate low capacity for
    bioaccumulation.

         Ethylene glycol is readily biodegradable in standard tests using
    sewage sludge. Many studies show biodegradation under both aerobic and
    anaerobic conditions. Some studies suggest a lag phase before

    degradation, but many do not. Degradation occurs in both adapted and
    unadapted sludges. Rapid degradation has been reported in surface
    waters (less in salt water than in fresh water), groundwater, and soil
    inocula. Several strains of microorganisms capable of utilizing
    ethylene glycol as a carbon source have been identified.

         Limited data are available on measured concentrations of ethylene
    glycol in environmental compartments. Levels measured in surface
    waters have been generally low, at a few micrograms per litre.
    Concentrations in wastewater from production plants, prior to
    treatment, have averaged up to 1300 mg/litre. By far the highest
    reported concentrations relate to runoff water from airports, with
    levels up to 19 000 mg/litre.

         Ethylene glycol has generally low toxicity to aquatic organisms.
    Toxic thresholds for microorganisms are above 1000 mg/litre. EC50s
    for growth in microalgae are 6500 mg/litre or higher. Acute toxicity
    tests with aquatic invertebrates where a value could be determined
    show LC50s above 20 000 mg/litre, and those with fish show LC50s
    above 17 800 mg/litre. An amphibian test showed an LC50 for tadpoles
    at 17 000 mg/litre. A no-observed-effect concentration (NOEC) for
    chronic tests on daphnids of 8590 mg/litre (for reproductive 
    end-points) has been reported. A NOEC following short-term exposure of
    fish has been reported at 15 380 mg/litre for growth.

         Tests using deicer containing ethylene glycol showed greater
    toxicity to aquatic organisms than observed with the pure compound,
    indicating other toxic components of the formulations.

         Laboratory tests exposing aquatic organisms to stream water
    receiving runoff from airports have demonstrated toxic effects and
    death. Field studies in the vicinity of an airport have reported toxic
    signs consistent with ethylene glycol poisoning, fish kills, and
    reduced biodiversity. These effects cannot definitively be ascribed to
    ethylene glycol. 

         Terrestrial organisms are much less likely to be exposed to
    ethylene glycol and generally show low sensitivity to the compound.
    Concentrations above 100 000 mg/litre were needed to produce toxic
    effects on yeasts and fungi from soil. Very high concentrations and
    soaking of seeds produced inhibition of germination in some
    experiments; these are not considered of environmental significance. A
    no-observed-effect level (NOEL) for orally dosed ducks at 1221 mg/kg
    body weight and reported lethal doses for poultry at around 8000 mg/kg
    body weight indicate low toxicity to birds.
    

    2.  IDENTITY AND PHYSICAL/CHEMICAL PROPERTIES

         Ethylene glycol (C2H6O2; CAS No. 107-21-1) is also known as
    1,2-ethanediol, 2-hydroxyethanol, 1,2-dihydroxyethane, glycol, glycol
    alcohol, ethylene alcohol, and monoethylene glycol or MEG. Its
    structure is illustrated below:

                               H    H
                               '    '
                          HO - C  - C - OH
                               '    '
                               H    H

         Ethylene glycol is a clear, colourless, syrupy liquid with a
    sweet taste but no odour. The molecular mass is 62.07. It has low
    volatility; its vapour pressure is 7.9 or 8.0 Pa at 20°C (Eisenreich
    et al., 1981; ATSDR, 1997) and 12.2 Pa at 25°C (HSDB, 1998). It is
    hygroscopic and absorbs twice its weight in water at 100% relative
    humidity (Budavari, 1989). It is miscible with water, lower aliphatic
    alcohols, glycerol, acetic acid, acetone and similar ketones,
    aldehydes, pyridine, and similar coal tar bases. The compound is
    slightly soluble in ether but practically insoluble in benzene and its
    homologues, chlorinated hydrocarbons, petroleum ethers, and oils
    (Budavari, 1989). The log octanol/water partition coefficient is -1.93
    (Hansch & Leo, 1979) to -1.36.1 Other physical and chemical
    properties can be found in the International Chemical Safety Card
    (ICSC 0270) reproduced in this document. 
                 

    1  Chou T, Hansch C (1986) Pomona College,
       Claremont, CA, unpublished (cited in BUA, 1991).
    

    3.  ANALYTICAL METHODS

         Ethylene glycol is measured in environmental samples by gas
    chromatography, most commonly using flame ionization detection. Recent
    methods have been described using high-resolution gas chromatography
    coupled with mass spectrometry. Measurement in biological samples has
    also used gas chromatography or high-resolution gas chromatography,
    with additional methods employing high-performance liquid
    chromatography or colorimetric determination. Detection limits were
    not available for environmental media. Details of extraction and
    concentration methods can be found in ATSDR (1997).
    

    4.  SOURCES OF ENVIRONMENTAL EXPOSURE

         Although ethylene glycol can be prepared directly by alkaline
    hydrolysis of chlorohydrin, hydrolysis of ethylene oxide is the more
    usual method. The feed stream consists of ethylene oxide (from either
    chlorohydrin or the direct oxidation of ethylene) and water. The
    mixture is fed under pressure into a reaction vessel at a temperature
    of about 100°C, which by the end of the reaction has risen to 170°C.
    Some diethylene and triethylene glycol are produced by the reaction of
    ethylene glycol with excess ethylene oxide. The crude glycol solution
    is concentrated in a multiple-effect evaporator, and final separation
    is achieved by distillation (Kent, 1974). Product proportions were
    estimated by the US EPA (1980) as follows: ethylene glycol,
    87.0-88.5%; diethylene glycol, 9.3-10.5%; and triethylene glycol,
    2.2-2.5%; and by ICI Chemicals and Polymers Ltd. as 90%, 9%, and 1%,
    respectively.1

         Estimated world production capacity was 9.4 million tonnes in
    1993.1 Total US production capacity was estimated at approximately 3
    million tonnes in 1993 (SRI, 1993); this figure had been more or less
    stable since 1989. United Kingdom production was estimated at 50 000 t
    in 1993 based on a production capacity of 85 000 t/year.1 Production
    volume in Germany was a maximum of 240 000 t in 1989; breakdown of
    production capacity by region and country worldwide can be found in
    BUA (1991). Production volume in Japan increased from 560 000 t in
    1992 to 751 000 t in 1996 (Chemical Daily Company, 1997).

         On a worldwide basis, approximately two-thirds of ethylene glycol
    is used as a chemical intermediate in the manufacture of polyesters
    for fibres, films, bottles, etc., with a further one-quarter used as
    an antifreeze in engine coolants. In Western Europe, the pattern is
    slightly different, with about half used in polyester manufacture and
    a quarter in coolants. Ethylene glycol is also used for runway deicing
    (the main source of high local concentrations in the environment), as
    plasticizer for adhesives, as softener for cellulose film, as
    glycoborates in electrolytic condensers, as glycol dinitrate in
    explosives, for various heat transfer applications, as humectant in
    inks, as antifreeze and plasticizer in paints, and to reduce gelling
    of medium oil alkyds based on pentaerythritol.2 There are many
    different formulations of ethylene glycol and propylene glycol for use
    in runway deicing. In some locations, one or the other of the glycols
    is used alone; more usually, however, they are used together. Other
    components of the formulation differ widely between manufacturers, as
    indicated by differing toxicity (see later sections). Details of
    formulations are not available.
                 

    1 ICI Chemicals and Polymers Ltd. (1993) Personal
      communication cited in Nielsen et al. (1993).

    2 Chou T, Hansch C (1986) Pomona College,
      Claremont, CA, unpublished (cited in BUA, 1991).

         Release to the atmosphere from production and processing of
    ethylene glycol and production of ethylene oxide was estimated at
    <875 t in Germany in 1989; release to the hydrosphere was estimated
    at <28 t from production and >2000 t from dispersed use as an
    antifreeze (BUA, 1991). A maximum figure of 12 500 t of ethylene
    glycol release from use as antifreeze in the United Kingdom, based on
    production figures and proportion of use, was derived in Nielsen et
    al. (1993); estimated release of total volatile organics to the
    atmosphere from glycol production was 41-260 t/year. Industry
    estimates of release to the environment from use in runway deicing in
    the United Kingdom were 600-720 t in 19931; use of the compound in
    runway deicers is declining. Details of releases reported through the
    US Toxic Release Inventory by individual state can be found in ATSDR
    (1997). Summary figures for the USA annually between 1990 and 1993
    were as follows: 4600 t to air, 523 t to water, 577 t to soil, and
    2675 t injected underground from production. Estimated figures of 6778
    t released via publicly owned treatment works and 60 252 t released to
    the environment away from production and industrial usage sites were
    reported for the same period (ATSDR, 1997).
                 

    1 ICI Chemicals and Polymers Ltd. (1993) Personal
      communication cited in Nielsen et al. (1993).
    

    5.  ENVIRONMENTAL TRANSPORT, DISTRIBUTION, AND TRANSFORMATION

         Ethylene glycol has a low vapour pressure (7.9 Pa at 20°C); it is
    expected to exist almost entirely in the vapour phase if released to
    the atmosphere (Eisenreich et al., 1981). The Henry's law constant for
    ethylene glycol is 1.41 × 10-3 or 6.08 × 10-3 Pa.m3/mol, depending
    on method of calculation (BUA, 1991), indicating a low capacity for
    volatilization from water bodies or soil surfaces.

         14C-labelled ethylene glycol adsorbed onto silica gel and
    irradiated with light (wavelength >290 nm) degraded by 12.1% over 17
    h (Freitag et al., 1985). Photodegradation is not expected, as the
    molecule should not absorb at these wavelengths; the mechanism of this
    breakdown is, therefore, unknown. Estimated half-life in the
    atmosphere for reaction with hydroxyl radicals is 2.1 days (BUA,
    1991), 8-84 h (Howard et al., 1991), or 1 day (Nielsen et al., 1993).

         No hydrolysis of ethylene glycol is expected in the environment
    (Lyman et al., 1982).

         Lokke (1984) studied the adsorption of ethylene glycol to three
    different soils in leaching experiments. There was effectively no
    sorption, and soil partition coefficients (log  Koc) of 0-0.62 were
    determined. Migration rates in five soil types were measured by
    Schramm et al. (1986) at between 4 and 27 cm per 12 h. 

         The low octanol/water partition coefficient of ethylene glycol
    (log  Kow -1.93 to -1.36) indicates a low potential for
    bioaccumulation. Bioconcentration factors of 190 for the green alga
     (Chlorella fusca) (Freitag et al., 1985), up to 0.27 in specific
    tissues of the crayfish ( Procambarus sp.) (Khoury et al., 1993), and
    10 for the golden orfe  (Leuciscus idus melanotus) (Freitag et al.,
    1985) confirm low bioaccumulation.

         In standard biodegradation tests under Organisation for Economic
    Co-operation and Development (OECD), US Environmental Protection
    Agency (US EPA), and Japanese Ministry of International Trade and
    Industry (MITI) guidelines, ethylene glycol was readily
    biodegradable.1

         Means & Anderson (1981) measured the biodegradation of ethylene
    glycol under aerobic conditions in five different tests using various
    aqueous media. Degradation was monitored using oxygen uptake,
    dissolved organic carbon removal, or carbon dioxide production.

                 

    1  Unpublished reports from Dow Chemicals, Union Carbide, and ICI
       Chemicals and Polymers Ltd.; cited in IUCLID (European Union
       database), 1st ed., 1996.

    Ethylene glycol was readily degraded in all tests with a lag period of
    up to 3 days. Degradation to 10% or less of the starting concentration
    was reported in all tests after between 1 and 21 days. Boatman et al.
    (1986) used acclimated sewage sludge as inoculum and a concentration
    of ethylene glycol equivalent to 20 mg carbon/litre. Significant
    degradation, as measured by carbon dioxide production, did not occur
    until day 14 of the test (an estimated lag period of 8-10 days was
    reported). By day 21, 71% of the ethylene glycol was degraded. Using
    activated sludge from a petrochemicals process, 92% chemical oxygen
    demand (COD) removal and 93% total organic carbon removal over 24 h
    were reported for ethylene glycol at an initial concentration of 172
    mg/litre by Matsui et al. (1975). However, direct measurement using
    gas chromatography showed 44% of ethylene glycol still present after
    24 h; the authors explain the discrepancy as being due to poor
    detection of the glycol by the analytical method used. Pitter (1976)
    reported 96.8% removal of ethylene glycol within 120 h using adapted
    activated sewage sludge based on COD measurements and an initial COD
    of 200 mg/litre. A biodegradation rate of 41.7 mg COD/g per hour was
    reported. Zahn & Wellens (1980) reported >90% degradation after 4
    days' incubation of ethylene glycol in a batch biodegradability study;
    no lag period was observed. Bridie et al. (1979) reported 36% of
    theoretical oxygen demand (ThOD) after 5 days' incubation at 20°C
    measured as biological oxygen demand (BOD) and 100% measured as COD;
    using previously adapted sludge, 63% degradation as BOD was reported
    after 5 days. Conway et al. (1983) reported 39% of theoretical BOD
    after 5 days, rising to 73% by day 10 and 96% at day 20, using
    domestic sewage sludge inoculum. Freitag et al. (1985) reported only
    5.7% degradation of ethylene glycol at 0.05 mg/litre over 5 days using
    municipal sewage sludge inoculum. McGahey & Bouwer (1992) studied
    degradation of ethylene glycol using primary sewage treatment effluent
    as the inoculum. After an initial lag period of 3 days, a typical
    first-order kinetic rate constant of 1.13 ± 0.34/day at 25°C was
    reported; the half-life for the reaction was calculated at between
    11.5 and 21.5 h.

         Evans & David (1974) studied the biodegradation of ethylene
    glycol in four samples of river water under controlled laboratory
    conditions. The samples were dosed with ethylene glycol at 0, 2, or 10
    mg/litre and incubated at either 20°C or 8°C. At 20°C, primary
    biodegradation was complete within 3 days in all four samples; at 8°C,
    it was complete by day 14. Degradation rates were further reduced at
    4°C. Price et al. (1974) assessed the biodegradation of ethylene
    glycol in both fresh and salt water over a 20-day incubation period.
    Concentrations of up to 10 mg ethylene glycol/litre were used. In
    fresh water, 34% degradation was observed after 5 days, rising to 86%
    by day 10 and 100% by day 20. Degradation was less in salt water
    -- 20% after 5 days and 77% after 20 days.

         McGahey & Bouwer (1992) studied the degradation of ethylene
    glycol using natural groundwater and soil inocula. An initial glycol
    concentration of 111 mg/litre was degraded in groundwater with a rate
    constant of 0.76/day at 25°C; the lag period was less than 3 days, and
    the half-life was estimated at 22 h. First-order degradation rate
    constants for sandy loam soil and sandy silt soil were 1.01 and
    2.90/day, respectively. A lag period of 3 days and a half-life of 16.5
    h were reported for the sandy loam, and a lag period of 0 days and a
    half-life of 6 h were reported for the sandy silt. Increasing the
    ethylene glycol concentration to 10 000 mg/litre in the sandy loam
    resulted in a greatly diminished rate constant of 0.05/day and minimal
    degradation of the glycol. Reducing temperature in the sandy silt
    inoculum from 25°C to 10°C resulted in a decrease in the rate constant
    from 2.09 to 1.19/day and an increase in the half-life from 6 to 14 h;
    however, nearly complete degradation was observed at both temperatures
    within the incubation period. Biodegradation rates of ethylene 
    glycol-based aircraft deicing fluids were examined in soil microcosms 
    at 8°C. Initial concentrations of 390-4900 ethylene glycol/kg soil 
    were degraded at around 20 mg/kg per day (Klecka et al., 1993).

         Haines & Alexander (1975) identified a soil bacterium
     (Pseudomonas aeruginosa) capable of degrading ethylene glycol. The
    bacterium had been originally grown on propylene glycol and was
    capable of degrading 1 mg carbon per inoculum within 2 days (based on
    oxygen consumption). Watson & Jones (1977) isolated bacteria from
    sewage effluent and identified  Acinetobacter and  Pseudomonas
    strains that degraded ethylene glycol.  Flavobacterium isolates did
    not degrade the compound. However, under strongly aerobic conditions,
     Flavobacterium sp. converted ethylene glycol to glycolate and
    eventually carbon dioxide (Willetts, 1981). 

         Dwyer & Tiedje (1983) assessed the degradation of ethylene glycol
    in methanogenic enrichments of bacteria obtained from municipal sewage
    sludge. The bacterial inoculum was dominated by two morphological
    types of bacteria,  Methanobacterium sp. and  Desulfovibrio sp. A
    concentration of 36 mmol ethylene glycol/litre (2.2 g/litre) was
    incubated at 37°C, and, based on analysis of the compound, 100% of the
    glycol was metabolized within 12 days. Products of degradation
    included ethanol, acetate, and methane. Battersby & Wilson (1989)
    assessed the degradation of ethylene glycol under methanogenic
    conditions using primary digesting sludge from a sewage treatment
    plant receiving both domestic and industrial wastewater. Degradation
    was assessed as total gas production. The glycol at a concentration of
    50 mg carbon/litre sludge was incubated at 35°C for 60 days. Total
    degradation was achieved after 1-2 weeks (>80% of theoretical gas
    production), and a short lag period of <1 day was reported. In
    anaerobic conditions using an inoculum from a pretreatment lagoon for
    petrochemical waste, ethylene glycol at a concentration of 135
    mg/litre was degraded to 78% after 10 days; at 755 mg/litre,

    degradation was 75-79% complete (Hovious et al., 1973). Under
    anaerobic conditions, ethylene glycol was degraded by 89% within 7
    days (Kameya et al., 1995). The anaerobic bacterium  Clostridium
     glycolicum isolated from pond ooze and adapted to ethylene glycol
    could degrade 5.3 or 6.7 g ethylene glycol/litre under anaerobic
    conditions (Gaston & Stadtman, 1963). Non-adapted  Acetobacter
    strains could degrade ethylene glycol at concentrations between 5 and
    15 g/litre using the compound as sole carbon source under anaerobic
    conditions (Kaushal & Walker, 1951; Hrotmatka & Polesofsky, 1962).

         Following a spill of ethylene glycol in New Jersey, USA, in which
    15 000 litres of coolant containing ethylene glycol as antifreeze at
    275 g/litre were spilled, concentrations of the glycol in soil and
    groundwater were measured at 4.9 and 2.1 g/litre, respectively. A
    remediation procedure was initiated involving the pumping of nitrogen,
    phosphate, and oxygen-saturated water into the contaminated ground;
    after 26 days, 85-93% of the glycol had been degraded by naturally
    occurring microorganisms. After 9 months, the concentration of
    ethylene glycol was below the detection limit of 50 mg/litre (Flathman
    et al., 1989).
    

    6.  ENVIRONMENTAL LEVELS

         The Japan Environment Agency (1991) reported the results of two
    environmental surveys of surface waters and sediments carried out in
    1977 and 1986. In the earlier survey, ethylene glycol was not detected
    in six samples of water and sediment (detection limits 0.1-0.4
    mg/litre and 1-2 mg/kg, respectively). In the later survey, the
    compound was not detected in 24 sediment samples (detection limit 0.06
    mg/kg) but was found in 2 out of 24 water samples at levels of 1.3 and
    2 µg/litre (detection limit 0.8 µg/litre).

         Monitoring of ethylene glycol in runoff from airports has been
    reviewed by Sills & Blakeslee (1992); levels in runoff water ranged up
    to several thousand mg/litre. Concentrations up to 19 000 mg/litre
    were reported for Salt Lake City International Airport, Salt Lake
    City, UT, USA, up to 3100 mg/litre for Lester B. Pearson International
    Airport in Toronto, Ontario, Canada, and up to 5050 mg/litre at
    Stapleton International Airport in Denver, CO, USA. Concentrations of
    up to 70 mg/litre were measured in stream water receiving runoff from
    Lester B. Pearson International Airport. Ethylene glycol was not
    detected in soil at the edge of runways in Denver, but levels of the
    compound in groundwater below the sandy soil of Ottawa International
    Airport, Ottawa, Ontario, Canada, were measured at up to 415 mg/litre;
    concentrations peaked in June and declined to non-detectable in the
    autumn. 

         Pitt et al. (1975) sampled the primary effluent from a municipal
    sewage treatment plant. No details are given in the report, but levels
    of ethylene glycol were reported at 3 µg/litre. Zeithoun & McIllhenny
    (1971) identified ethylene glycol in the wastewater from glycol
    production; in 51 samples from two production plants, concentrations
    in wastewater ranged from 680 to 2300 mg/litre (average 1003-1306
    mg/litre). In a similar number of samples from two 1,2-propanediol
    production plants, concentrations of ethylene glycol in wastewater
    ranged from 355 to 2550 mg/litre (average 960-1140 mg/litre).
    Grabinska-Loniewska (1974) identified ethylene glycol as a constituent
    of wastewater from a polyester fibre plant in Poland. Concentrations
    ranged from 200 to 440 mg/litre (average 200 mg/litre, number of
    samples unspecified).

         Influent-contaminated groundwater to a bioremediation plant in
    California, USA, contained ethylene glycol at up to 103 mg/litre (Ross
    et al., 1988).

         Lee et al. (1983) detected ethylene glycol in two samples of
    Asiatic clams ( Corbicula sp.); no levels were reported. 

         Ethylene glycol was detected in ambient air at time-weighted
    averages of <0.05-0.33 mg/m3 as aerosol and <0.05-10.4 mg/m3 as
    vapour following spray application of deicer containing 50% of the
    compound to bridges (LDOTD, 1990).

         Ethylene glycol has been identified as a metabolite of the growth
    regulator ethylene in a number of higher plants (Blomstrom & Beyer,
    1980) and as naturally occurring in the edible fungus  Tricholoma
     matsutake (Ahn & Lee, 1986). 
    

    7.  EFFECTS ON ORGANISMS IN THE LABORATORY AND FIELD

    7.1  Aquatic organisms

         Results of acute toxicity tests on aquatic organisms are
    summarized in Table 1. Chronic toxicity tests were conducted on water
    fleas  (Ceriodaphnia dubia) over the period taken by 60% of the
    controls to produce three broods. NOECs for mortality at 24 000
    mg/litre and for reproduction at 8590 mg/litre were reported; an IC25
    of 12 310 mg/litre was calculated. Seven-day toxicity tests conducted
    on the fathead minnow  (Pimephales promelas) gave NOECs for mortality
    and growth at 32 000 mg/litre and 15 380 mg/litre, respectively, with
    an IC25 at 22 520 mg/litre (Pillard, 1995). Masters et al. (1991)
    exposed  Ceriodaphnia dubia to ethylene glycol in the US EPA standard
    7-day chronic toxicity test and also concurrently carried out 4-day
    tests to compare results. Survival and production of young were
    monitored. A "chronic index," the geometric mean of the NOEC and
    lowest-observed-effect concentration (LOEC), was determined to be 4.2
    mg/litre for production of young in both tests and >6.0 and 4.2
    mg/litre for survival in the 4- and 7-day tests, respectively. Actual
    NOECs and LOECs were not reported.

         Mayes et al. (1983) compared the toxicity of ethylene glycol to
    fathead minnows at three different ages (fry, 10-15 days old;
    juveniles, 30-35 days old; and subadults, 60-94 days old) and found no
    effect of age. However, Mayer & Ellersieck (1986) found older (1.1 g)
    rainbow trout  (Oncorhynchus mykiss) more sensitive than younger
    (0.7 g) fish.

         Ethylene glycol did not produce narcosis in tadpoles of the
    common frog  (Rana temporaria) at 28 550 mg/litre; tadpoles did
    become sluggish after 5-6 h of exposure, but did not lose their
    responsiveness to stimuli. However, death followed within 12-20 h. At
    14 275 mg/litre, tadpoles kept moving for 24-30 h but died after about
    36-48 h (Lipnick, 1991).

         A reported 48-h LC50 value for tadpoles of the clawed toad
     (Xenopus laevis) at 326 mg/litre (DeZwart & Slooff, 1987) is
    considered invalid for the setting of standards following
    correspondence from the authors. The study was part of a technicians'
    training course, and no quality control was exercised.

    7.1.1  Toxicity of deicer formulations

         Pillard (1995) conducted acute and chronic tests on water fleas
     (C. dubia) and fathead minnows using both pure ethylene glycol and
    formulations of deicer based on the compound. For acute tests, 48-h
    LC50s for the daphnid were 34 440 and 13 140 mg/litre for the pure
    substance and formulation, respectively; chronic NOECs for survival
    were 24 000 and 8400 mg/litre, respectively, and for reproduction,

    8590 and <3330 mg/litre, respectively. For acute tests on the
    minnows, 96-h LC50s were 72 860 and 8050 mg/litre, respectively;
    chronic NOECs for survival were 32 000 and 6090 mg/litre and for
    growth were 15 380 and <3330 mg/litre, respectively. The higher
    toxicity of formulations was ascribed to other unknown constituents of
    the formulations, including rust inhibitors, buffers, polymers, and
    surfactants. Hartwell et al. (1995) conducted toxicity tests using
    ethylene glycol-based deicer and determined 96-h LC50s for fathead
    minnow,  Daphnia magna, D. pulex, and  C. dubia at 10 802, 4213,
    4675, and 9845 mg glycol/litre, respectively. Seven-day exposure of
    fathead minnows produced an identical LC50. A maximum acceptable
    toxicant concentration (MATC) for reproduction of  Ceriodaphnia was
    calculated at 418 mg/litre. Gill and kidney lesions and calcium
    oxalate crystals were found in exposed fish. The same species were
    also cultured in stream water taken from an outflow stream from
    stormwater basins at Baltimore Washington International Airport,
    Maryland, USA, receiving runoff from deicing of runways. No fish
    mortality was seen in either March or April water samples over 7 days.
    However, oxalate crystals were seen after 7 days' exposure to the
    March water. Significant reduction in survival of  D. magna and  D.
     pulex was recorded over 96 h in the March water sample.  Ceriodaphnia
     dubia showed reduced survival only after 7 days, and production of
    neonates was also reduced to 55% of controls. No significant adverse
    effects on daphnids was seen with the April water (neonate production
    was significantly increased in  Ceriodaphnia).

         Toxicity of formulations will vary considerably depending on the
    particular constituents. For example, Union Carbide's UCAR 50/50
    EG-Based Type I fluid for the 1997-98 aircraft deicing season has
    lower aquatic toxicity figures than those quoted in the literature:
     D. magna, 48-h EC50 88 000 mg/litre; fathead minnow, 96-h LC50
    44 000 mg/litre; rainbow trout, 96-h LC50 34 200 mg/litre.1 For an
    assessment of likely effects in the field, toxicity values for
    particular formulations used will need to be determined.

    7.1.2  Field effects

         During early summer, 3 months after release of glycols into
    streams draining from airport stormwater basins (Baltimore Washington
    International Airport), fish were sampled from the stream. In
    tesselated darters  (Etheostoma olmstedi), oxalate crystals appeared
    in the interstitial tissue of the kidneys and basal layers of tubules.
    American eels  (Aguilla rostrata) exhibited kidney lesions consistent
    with oxalate damage, but no crystals were found.2 Pillard (1995)
    cites his own unpublished report as showing fish kills in streams near
    airports and aquatic community impairment in three streams receiving
    runoff from airports. 
                 

    1 Personal communication to IPCS.

    2 Unpublished reports cited by Hartwell et al. (1995).

    7.2  Terrestrial organisms

         Incubation of yeast  (Saccharomyces cerevisiae) in ethylene
    glycol at a concentration of 150 g/litre produced a 1% reduction in
    glucose utilization; a concentration of 172.5 g/litre produced <10%
    inhibition (Gray & Sova, 1956). Concentrations of 200 g ethylene
    glycol/litre prevented germination of conidia of the ascomycete fungus
     Neurospora crassa; return to clean medium allowed germination.
    Concentrations greater than 200 g/litre killed the spores (Bates &
    Wilson, 1974). Using oxygen uptake and growth (turbidity) as
    end-points, Khoury et al. (1990) reported an IC50 for heterotrophic
    soil microorganisms at 114 300 mg/litre.

         Bose & Bandyopadhyay (1975) soaked tomato seeds in ethylene
    glycol solution at 5.5 g/litre. Only 50% of the soaked seeds
    germinated, but those that did grew higher, bloomed earlier, and
    carried twice the crop of untreated plants. Soaking of cluster bean
     (Cyamopsis tetragonoloba) in aqueous ethylene glycol solutions at 10
    or 20 g/litre for 8 h, following an initial 4-h soak in water, led to
    some plants showing small leaves with shortened petioles, stunted
    growth, and sterility (Bose & Naskar, 1975). Twenty-three percent of
    rice seeds soaked in aqueous ethylene glycol at 10 g/litre for 24 h
    germinated (compared with 48% of controls). Germinated plants showed
    only marginal effects on growth, panicle length, grain weight, and
    fertility, but tiller numbers were reduced by 40-50% compared with
    controls (Bose & Bhattacharyya, 1975). Jute  (Corchorus capsularis)
    seeds soaked in ethylene glycol solution at 2 g/litre showed 84% of
    control levels of germination. Plants that germinated following
    treatment required 8 days longer to blossom, on average, showed a
    higher degree of pollen sterility, and produced fewer and lighter
    seeds than controls (Bose & Datta, 1973). Tobacco  (Nicotiana xanthi)
    plants sprayed with 5 ml of a solution of ethylene glycol at 34.
    51.5, or 69 g/litre showed a dose-dependent 10-33% reduction in
    terminal bud fresh weight, but no other overt effects were noted
    (Steffens & Barer, 1984).

         Toxic effects (unspecified) were noted in chickens fed a diet
    containing 5% ethylene glycol for 27 days (Yoshida et al., 1969). An
    LC50 for ethylene glycol in drinking-water at 75 100 mg/litre over 24
    h was reported for chickens (Riddell et al., 1967). No deaths were
    seen in chickens exposed through drinking-water at 27 800 mg/litre,
    but renal oxalosis was observed. Chickens exposed at 14 500 mg/litre
    drinking-water showed calcium oxalate crystals in renal tubules, but
    no clinical signs were reported. Beasley & Buck (1980) reported lethal
    doses for poultry to lie within the range of 7790-8900 mg/kg body
    weight. A NOEL of 1221 mg/kg body weight and a lowest-observed-effect
    level (LOEL) of 2553 mg/kg body weight were reported for orally dosed
    mallard ducks  (Anas platyrhynchos) (Stowe et al., 1981).


        Table 1: Acute toxicity of ethylene glycol to aquatic organisms.
                                                                                                                                               

    Organism                               End-point                             Concentration (mg/litre)          Reference
                                                                                                                                               

    Microorganisms

    bacterium Pseudomonas                  Toxic threshold                       >10 000                           Bringmann & Kuhn (1980a,b)
    putida; protozoa                       (cell multiplication)
    Entosiphon sulcatum,
    Uronema parduczi

    cyanobacterium Microcystis             Toxic threshold                       2000                              Bringmann & Kuhn (1976)
    aeruginosa                             (cell multiplication)

    bacterium Pseudomonas                  EC0 (growth)                          1000                              Daugherty (1980)
    aeruginosa                             EC100 (growth)                        2000

    bacterium Photobacterium               30-min EC50 (luminescence)            621                               Kaiser & Palabrica (1991)
    phosphoreum                            5-min EC50                            112 220                           Calleja et al. (1993)
                                           5-min EC50                            166 000                           Kahru et al. (1996)

    bacteria from aquatic sediment         EC50 (growth)                         114 300                           Khoury et al. (1990)
    and sewage sludge

    bacteria from sewage sludge            EC50 (oxygen uptake)                  224 600                           Kilroy & Gray (1992)

    anaerobic bacteria from sewage         Toxic threshold                       5000                              Hoechst (1975)
    sludge 

    flagellate euglenoid                   EC5 (growth in population)            >10 000                           AQUIREa 

    Algae

    green alga Scenedesmus quadricauda     Toxic threshold                       >10 000                           Bringmann & Kuhn (1980a)

    green alga Selenastrum capricornutum   96-h EC50 (growth, cell counts)       6500-7500                         Dowb
                                           96-h EC50 (growth, cell volume)       9500-13 000
                                           168-h EC50 (growth, cell volume)      24 000

    Table 1 (cont'd)
                                                                                                                                               

    Organism                                 End-point                              Concentration (mg/litre)              Reference
                                                                                                                                               

    Invertebrates

    water flea Daphnia magna                 48-h LC50 (immobilization)             >10 000                               Conway et al. (1983)
                                                                                    50 000                                Hermens et al. (1984)
                                                                                    41 000-51 000                         Gersich et al. (1986)
                                                                                    74 400                                Calleja et al. (1994)
                                                                                    14 828c                               Hartwell et al. (1995)
                                             24-h LC50                              >10 000                               Bringmann & Kuhn (1977)
                                             24-h NOEC                              2500

    water flea Ceriodaphnia dubia            48-h LC50                              25 800                                Cowgill et al. (1985)
                                                                                    (22 600-29 900)
                                                                                    34 440                                Pillard (1995)

    crayfish Procambarus sp.                 96-h LC50                              91 430                                Khoury et al. (1990)

    common shrimp Crangon vulgaris           96-h LC50                              50 000                                AQUIREa 

    brine shrimp Artemia salina              24-h LC50                              >20 000                               Price et al. (1974)
                                                                                    180 420                               Calleja et al. (1994)

    brown shrimp Crangon crangon             96-h LC50                              approx. 50 000                        Blackman (1974)

    Fish

    rainbow trout Oncorhynchus mykiss        96-h LC50                              >18 500                               Jank et al. (1974)
                                                                                    17 800-45 600                         Mayer & Ellersieck 
                                                                                                                          (1986)
    guppy Poecilia reticulata                168-h LC50                             49 300                                Konnemann (1981)

    bluegill sunfish Lepomis macrochirus     96-h LC50                              >111 300                              Mayer & Ellersieck       
                                                                                                                          (1986)
                                                                                    27 540                                Khoury et al. (1990)

    Table 1 (cont'd)
                                                                                                                                               

    Organism                                 End-point                              Concentration (mg/litre)              Reference
                                                                                                                                               

    fathead minnow Pimephales promelas       96-h LC50                              >10 000                               Conway et al. (1983)
                                                                                    49 000-57 000                         Mayes et al. (1983)
                                                                                    72 860                                Pillard (1995)

    goldfish Carassius auratus               24-h LC50                              >5000                                 Bridie et al. (1979)
    Japanese killifish Oryzias latipes       48-h NOEC                              900                                   Tsuji et al. (1986)

    Amphibians

    frog (tadpoles) Rana brevipoda           48-h LC50                              17 000                                Nishiushi (1984)
                                                                                                                                               

    a AQUIRE (Aquatic Information Retrieval) Computerized database developed by the US Environmental Protection Agency.
    b Dow (undated) Personal communication to IPCS.
    c Value based on ethylene glycol content of a deicing product.
        


    8.  EFFECTS EVALUATION

         Ethylene glycol released to the atmosphere will be degraded by
    reaction with hydroxyl radicals; the half-life for this reaction has
    been estimated at between 0.3 and 3.5 days.

         No hydrolysis of ethylene glycol is expected in surface waters.

         The compound has little or no capacity to bind to particulates
    and will be mobile in soil.

         The low octanol/water partition coefficient and measured
    bioconcentration factors in a few organisms indicate low capacity for
    bioaccumulation.

         Ethylene glycol is readily biodegradable in standard tests using
    sewage sludge. Many studies show biodegradation under both aerobic and
    anaerobic conditions. Some studies suggest a lag phase before
    degradation, but many do not. Degradation occurs in both adapted and
    unadapted sludges. Rapid degradation has been reported in surface
    waters (less in salt water than in fresh water), groundwater, and soil
    inocula. Several strains of microorganisms capable of utilizing
    ethylene glycol as a carbon source have been identified.

         Limited data are available on measured concentrations of ethylene
    glycol in environmental compartments. Levels measured in surface
    waters have been generally low, at a few micrograms per litre.
    Concentrations in wastewater from production plants, prior to
    treatment, have averaged up to 1300 mg/litre. By far the highest
    reported concentrations relate to runoff water from airports, with
    levels up to 19 000 mg/litre.

         Ethylene glycol has generally low toxicity to aquatic organisms.
    Toxic thresholds for microorganisms are above 1000 mg/litre. EC50s
    for growth in microalgae are 6500 mg/litre or higher. Acute toxicity
    tests with aquatic invertebrates where a value could be determined
    show LC50s above 20 000 mg/litre, and those with fish show LC50s
    above 17 800 mg/litre. The only valid acute toxicity value for
    amphibians is 17 000 mg/litre for  Rana brevipoda tadpoles. A NOEC
    for chronic tests on daphnids of 8590 mg/litre (for reproductive
    end-points) has been reported. A NOEC following short-term exposure of
    fish has been reported at 15 380 mg/litre for growth.

         Tests using deicer containing ethylene glycol generally showed
    greater toxicity to aquatic organisms than the pure compound,
    indicating other toxic components of the formulations.

         Laboratory tests exposing aquatic organisms to stream water
    receiving runoff from airports have demonstrated toxic effects and
    death. Field studies in the vicinity of an airport have reported toxic
    signs consistent with ethylene glycol poisoning (oxalate crystal
    formation), fish kills, and reduced biodiversity. These effects cannot
    definitively be ascribed to ethylene glycol.

         Terrestrial organisms are much less likely to be exposed to
    ethylene glycol and generally show low sensitivity to the compound.
    Concentrations above 100 000 mg/litre were needed to produce toxic
    effects on yeasts and fungi from soil. Very high concentrations and
    soaking of seeds produced inhibition of germination in some
    experiments; these are not considered of environmental significance. A
    NOEL for orally dosed ducks at 1221 mg/kg body weight and reported
    lethal doses for poultry at around 8000 mg/kg body weight indicate low
    toxicity to birds.

    8.1  Predicted environmental concentration

         There are reported measurements of ethylene glycol in the influx
    wastewater to treatment plants at industrial sites manufacturing the
    compound. These will be used as the basis for calculating a predicted
    environmental concentration (PEC) after treatment. Average
    concentrations up to 1306 mg/litre have been reported.

         Based on this emission concentration, and using mainly default
    values from the OECD Technical Guidance Manual, the initial
    concentration in river water would be as follows:

         PEClocal (water) =  Ceffluent/[(1 +  Kp(susp) ×  C(susp)) ×  D]

    where:

    *    PEClocal (water) is the predicted environmental concentration (g/litre)

    *     Ceffluent is the concentration of the chemical in the wastewater
         treatment plant effluent (g/litre), calculated as  Ceffluent =  I
         × (100 -  P)/100,

    where:

          I    =    input concentration to the wastewater treatment plant
                   (1.3 g/litre)

          P    =    percent removal in the wastewater treatment plant (91%,
                   based on the "ready biodegradability" of the compound)

    *     Kp(susp) is the suspended matter/water adsorption coefficient,
         calculated as  Kp(susp) =  foc(susp) ×  Koc, where:

          foc(susp)    =   the fraction of organic carbon in suspended matter
                          (default 0.1)

          Koc          =     0.411 ×  Kow

    where:

          Kow     = the octanol/water partition
                       coefficient (log  Kow = -1.36)

    *     C(susp) is the concentration of suspended matter in the river
         water in kg/litre (default concentration 15 mg/litre)

    *     D is the dilution factor for river flow (a conservative default
         value of 10)

         Under these very conservative conditions, PEClocal (water) = 11.7
    mg/litre. This is substantially higher than reported concentrations in
    surface water and represents a conservative estimate of initial
    maximum concentration.

    8.2  Predicted no-effect concentration

         There is a substantial database on the toxicity of ethylene
    glycol to aquatic organisms, representing acute and chronic test
    results for two trophic levels and acute and short-term results for a
    third. The distribution of test results is presented in Figure 1 for
    different types of organism. The shaded points represent toxic
    thresholds for microorganisms or algae, and these are not considered a
    suitable basis for estimating a predicted no-effect concentration
    (PNEC). It would be justifiable to apply an uncertainty factor of 10
    to the chronic NOEC for daphnid reproduction at 8590 mg/litre given
    the wide range of available data. This gives a PNEC of 859 mg/litre.        

    8.3  Environmental risk factors

         It is clear from Figure 1 that risk to aquatic organisms from
    production of ethylene glycol is very low, even based on conservative
    assumptions; a risk factor of 0.013 is generated by comparing PEClocal
    (water) against PNEC. Based on the few measured values in surface waters,
    risk would be negligible (risk factor at 2.3 × 10-6).

         It is also clear that concentrations in airport runoff would be
    expected to cause severe field effects without mitigation. It is
    difficult to estimate likely dilution of runoff in generalized terms;
    however, dilution factors of at least 100-fold would be needed for the
    reported concentrations. Concentrations may be substantially higher in
    runoff water at particular airport sites. There is indication that

    formulations might be significantly more toxic to aquatic organisms
    than the pure ethylene glycol. It is also unlikely that only ethylene
    glycol formulations would be used. The ready biodegradability of
    glycols also increases risk to organisms from oxygen depletion in
    surface waters. Risk assessment and field monitoring of overt effects
    should be applied on a case-by-case basis to determine pollution
    control measures needed.

    FIGURE 2


    


    INTERNATIONAL CHEMICAL SAFETY CARD
                                                                                                                                                   

    ETHYLENE GLYCOL                                                               ICSC: 0270
                                                                                  March 1999
                                                                                                                                               

    CAS #     107-21-1                                1,2-Ethanediol
    RTECS #   KW2975000                               1,2-Dihydroxyethane
    EC #      803-027-00-1                            HOCH2CH2OH
                                                      Molecular mass: 82.1
                                                                                                                                               
    TYPES OF HAZARD                  ACUTE HAZARDS /                   PREVENTION                        FIRST AID / FIRE
    /EXPOSURE                        SYMPTOMS                                                            FIGHTING
                                                                                                                                               
    FIRE                             Combustible.                      NO open flames.                   Powder, alcohol-resistant 
                                                                                                         foam, water spray,
                                                                                                         carbon dioxide.
                                                                                                                                               
    EXPLOSION
                                                                                                                                               
    EXPOSURE                                                           PREVENT GENERATION OF
                                                                       MISTS!
                                                                                                                                               
    Inhalation                       Cough. Dizziness.                 Ventilation.                      Fresh air, rest. Artificial 
                                     Headache.                                                           respiration if indicated. Refer
                                                                                                         for medical attention.
                                                                                                                                               
    Skin                             Dry skin.                         Protective gloves.                Remove contaminated clothes. 
                                                                                                         Rinse skin with plenty of water
                                                                                                         or shower.
                                                                                                                                               
    Eyes                             Redness. Pain.                    Safety goggles.                   First rinse with plenty of water 
                                                                                                         for several minutes (remove contact
                                                                                                         lenses if easily possible), 
                                                                                                         then take to a doctor.
                                                                                                                                               

    Ingestion                        Abdominal pain. Dullness.         Do not eat, drink,                Rinse mouth. Induce vomiting (ONLY 
                                     Nausea. Unconsciousness.          or smoke during work.             IN CONSCIOUS PERSONS!). Refer for
                                     Vomiting.                                                           medical attention. If no medical 
                                                                                                         personnel are available and the
                                                                                                         patient is conscious, ingestion 
                                                                                                         of alcoholic beverage may prevent
                                                                                                         kidney failure.
                                                                                                                                               
    SPILLAGE DISPOSAL                                                  PACKAGING & LABELLING
                                                                                                                                               
    Collect leaking and spilled liquid                                 EU Classification
    in sealable containers as far as possible. Wash                    Symbol: Xn
    away remainder with plenty of water. (Extra                        R: 22
    personal protection: A/P2 filter respirator                        S: (2-)
    for organic vapour and                                             UN Classification
    harmful dust).
                                                                                                                                               
    EMERGENCY RESPONSE                                                 STORAGE
                                                                                                                                               
    NFPA Code: H1; F1; R0;                                             Separated from strong
                                                                       oxidants, strong bases. Dry.
                                                                       Ventilation along the floor.
                                                                                                                                               
                                                          IMPORTANT DATA
                                                                                                                                               
    PHYSICAL STATE; APPEARANCE:                                        ROUTES OF EXPOSURE:

    ODOURLESS, COLOURLESS, VISCOUS,                                    The substance can be absorbed 
    HYDROSCOPIC LIQUID                                                 into the body by inhalation and
                                                                       through the skin.

    CHEMICAL DANGERS:                                                  INHALATION RISK:

    On combustion, forms toxic gases.                                  A harmful contamination of the air will
    Reacts with strong oxidants and strong bases.                      be reached rather slowly on
                                                                       evaporation of this substance at 20°C.

    OCCUPATIONAL EXPOSURE LIMITS:                                      EFFECTS OF SHORT-TERM EXPOSURE:

    TLV (as STEL): ppm; 100 mg/m3                                      The substance Irritates the eyes and the
    (ceiling values) (ACGIH 1998).                                     respiratory tract. The substance
                                                                       may cause effects on the the kidneys and
                                                                       central nervous system, resulting
                                                                       in renal failure and brain Injury.
                                                                       Exposure could cause lowering of
                                                                       consciousness.

                                                                       EFFECTS OF LONG-TERM OR REPEATED EXPOSURE:

                                                                       The substance may have effects on the central
                                                                       nervous system, resulting
                                                                       in abnormal eye movements (nystagmus).
                                                                                                                                               
                                                       PHYSICAL PROPERTIES
                                                                                                                                               
    Boiling point: 198°C                                               Auto-ignition temperature: 398°C
    Melting point: -13°C                                               Explosive limits, vol% in air. 3.2-15.3
    Relative density (water = 1): 1.1                                  Octanol/water partition coefficient as log Pow: -1.93
    Solubility in water: miscible
    Vapour pressure, Pa at 20°C: 7
    Relative vapour density (air = 1): 2.1
    Relative density of the
    vapour/air-mixture at 20°C (air = 1): 1.00
    Flash point: 111°C (C.C.)
                                                                                                                                               
                                                       ENVIRONMENTAL DATA
                                                                                                                                               
                                                              NOTES
                                                                                                                                               
    The occupational exposure limit value should not be exceeded during any part of the working exposure.
                                                                                                                                               

                                                 ADDITIONAL INFORMATION
                                                                                                                                               







                                                                                                                                               
    LEGAL NOTICE          Neither the CEC nor the IPCS nor any person acting on behalf of the CEC or the IPCS is 
                          responsible for the use which might be made of this information
                                                                                                                                               
    (c) IPCS, CEC 1999
        


    REFERENCES

    Ahn JS, Lee KH (1986) Studies on the volatile aroma components of
    edible mushroom  (Tricholoma matsutake) of Korea.  Journal of the
     Korean Society for Food and Nutrition, 15:253-257.

    ATSDR (1997)  Toxicological profile for ethylene glycol and propylene
     glycol. Atlanta, GA, US Department of Health and Human Services,
    Public Health Service, Agency for Toxic Substances and Disease
    Registry. 249 pp.

    Bates WK, Wilson JF (1974) Ethylene glycol-induced alteration of
    conidial germination in  Neurospora crassa.  Journal of bacteriology,
    117:560-567.

    Battersby NS, Wilson V (1989) Survey of the anaerobic biodegradation
    potential of organic chemicals in digesting sludge.  Applied
     environmental microbiology, 55(2):433-439.

    Beasley VR, Buck WB (1980) Acute ethylene glycol toxicosis: A review.
     Veterinary and human toxicology, 22(4):255-263. 

    Blackman RAA (1974) Toxicity of oil-sinking agents.  Marine pollution
     bulletin, 5:116-118.

    Blomstrom DC, Beyer EM (1980) Plants metabolise ethylene to ethylene
    glycol.  Nature, 283(5742):66-68.

    Boatman RJ, Cunningham SL, Ziegler DA (1986) A method for measuring
    the biodegradation of organic chemicals.  Environmental toxicology and
     chemistry, 5:233-243.

    Bose S, Bandyopadhyay M (1975) Effect of dimethyl sulfoxide, ethylene
    glycol and hydroxylamine on tomato  (Lycopersicon esculentum Mill.).
     Science and culture, 41:240-241.

    Bose S, Bhattacharyya SK (1975) Studies on the effect of single and
    combined treatments of x-rays, ethylene glycol and hydroxylamine in
    rice  (Oryza sativa L.).  Plant science, 7:19-22.

    Bose S, Datta GC (1973) Effect of treatments of colchicine,
    dimethylsulphoxide, ethylene glycol, hydroxylamine and triethanolamine
    in jute  (Corchorus capsularis L.).  Bangladesh journal of botany,
    2:1-6.

    Bose S, Naskar SK (1975) Effect of dimethyl sulfoxide, ethylene
    glycol, hydroxylamine and triethanolamine in M1 generation in cluster
    bean.  Bulletin of the Botanical Society of Bengal, 29:49-52.

    Bridie A, Wolff CJM, Winter M (1979) BOD and COD of some
    petrochemicals.  Water research, 13:627-630.

    Bringmann G, Kuhn R (1976) Comparative findings on the damaging
    effects of water pollutants in bacteria  (Pseudomonas putida) and
    blue-green algae  (Microcystis aeruginosa).  GasWasserfach: Wasser
     Abwasser, 117(9):410-413 (in German).

    Bringmann G, Kuhn R (1977) Results of the damaging effect of water
    pollutants on  Daphnia magna.  Zeitschrift fuer Wasser und Abwasser
     Forschung, 10:161-166 (in German).

    Bringmann G, Kuhn R (1980a) Comparison of the toxicity thresholds of
    water pollutants to bacteria, algae and protozoa in the cell
    multiplication inhibition test.  Water research, 14:231-241.

    Bringmann G, Kuhn R (1980b) Determination of the biological effects of
    water pollutants in protozoa. II. Ciliated bacteria.  Zeitschrift fuer
     Wasser und Abwasser Forschung, 13(1):26-31 (in German).

    BUA (1991)  Ethylene glycol. GDCh-Advisory Committee on Existing
    Chemicals of Environmental Relevance (BUA). Hirzel, Wissenschaftliche
    Verlagsgesellschaft. 139 pp. (BUA Report 92.S).

    Budavari S, ed. (1989)  The Merck Index. An encyclopaedia of
     chemicals, drugs and biologicals, 11th ed. Rahway, NJ, Merck 
    and Co. Inc.

    Calleja MC, Persoone G, Geladi P (1993) The predictive potential of a
    battery of ecotoxicological tests for human acute toxicity as
    evaluated with the first 50 MEIC chemicals.  Alternatives to
     laboratory animals, 21:330-349.

    Calleja MC, Persoone G, Geladi P (1994) Comparative acute toxicity of
    the first 50 multicentre evaluation of  in vivo cytotoxicity
    chemicals to aquatic non-vertebrates.  Archives of environmental
     contamination and toxicology, 26:69-78.

    Chemical Daily Company (1997)  Annual of chemical industry. Tokyo,
    The Chemical Daily Company Ltd. 

    Conway RA, Waggy GT, Spiegel MH, Berglund RL (1983) Environmental fate
    and effects of ethylene oxide.  Environmental science and technology,
    17(2):107-112.

    Cowgill UM, Takahashi IT, Applegath SL (1985) A comparison of the
    effect of four benchmark chemicals on  Daphnia magna and
     Ceriodaphnia dubia-affinis tested at two different temperatures.
     Environmental toxicology and chemistry, 4:415-422.

    Daugherty LC (1980) The growth of  Pseudomonas aeruginosa on glycols
    of industrial importance.  Lubrication engineering, 36(12):718-723.

    DeZwart D, Slooff W (1987) Toxicity of mixtures of heavy metals and
    petrochemicals to  Xenopus laevis.  Bulletin of environmental
     contamination and toxicology, 38:345-351.

    Dwyer DF, Tiedje JM (1983) Degradation of ethylene glycol and
    polyethylene glycols by methanogenic consortia.  Applied environmental
     microbiology, 46(1):185-190.

    Eisenreich SJ, Looney BB, Thornton JD (1981) Airborne organic
    contaminants in the Great Lakes ecosystem.  Environmental science and
     technology, 15(1):30-38.

    Evans WH, David EJ (1974) Biodegradation of mono-, di-, and
    triethylene glycols in river waters under controlled laboratory
    conditions.  Water research, 8(2):97-100.

    Flathman PE, Jerger DE, Bottomley LS (1989) Remediation of
    contaminated ground water using biological techniques.  Ground water
     monitoring review, 9:105-119.

    Freitag D, Ballhorn L, Geyer H, Korte F (1985) Environmental hazard
    profile of organic chemicals: An experimental method for the
    assessment of the behaviour of organic chemicals in the ecosphere by
    means of simple laboratory tests with 14C labeled chemicals.
     Chemosphere, 14(10):1589-1616.

    Gaston LW, Stadtman ER (1963) Fermentation of ethylene glycol by
     Clostridium glycolicum.  Journal of bacteriology, 85:356-362.

    Gersich FM, Blanchard FA, Applegath SL, Park CN (1986) The precision
    of daphnid  (Daphnia magna Straus, 1820) static acute toxicity tests.
     Archives of environmental contamination and toxicology, 
    15(6):741-749.

    Grabinska-Loniewska A (1974) Studies on the activated sludge bacteria
    participating in the biodegradation of methanol, formaldehyde and
    ethylene glycol: II. Utilization of various carbon and nitrogen
    compounds.  Acta Microbiologica Polonica, Series B: Microbiologia
     Applicata, 6(2):83-88.

    Gray WD, Sova C (1956) Relation of molecule size and structure to
    alcohol inhibition of glucose utilization by yeast.  Journal of
     bacteriology, 72:349-356.

    Haines JR, Alexander M (1975) Microbial degradation of polyethylene
    glycols.  Applied microbiology, 29:621-625.

    Hansch C, Leo AJ (1979) Substituent constants for correlation analysis
    in chemistry and biology. New York, NY, John Wiley & Sons.

    Hartwell SI, Jordahl DM, Evans JE, May EB (1995) Toxicity of aircraft
    de-icer and anti-icer solutions to aquatic organisms.  Environmental
     toxicology and chemistry, 14:1375-1386.

    Hermens J, Canton H, Janssen P, De Jong R (1984) Quantitative
    structure activity relationships and toxicity studies of mixtures of
    chemicals with anaesthetic potency: Acute lethal and sublethal
    toxicity to  Daphnia magna.  Aquatic toxicology, 5:143-154. 

    Hoechst (1975)  Investigation of the biodegradation of ethylene
     glycol. Frankfurt/Main, Germany, Hoechst AG, Abteilung Reinhaltung
    von Wasser und Luft (in German).

    Hovious JC, Conway RA, Ganze CW (1973) Anaerobic lagoon pretreatment
    of petrochemical wastes.  Journal of the Water Pollution Control
     Federation, 45:71-84.

    Howard PH, Boethling RS, Jarvis WF, Meylan WM, Michalenko EM (eds.)
    (1991)  Handbook of environmental degradation rates. Chelsea, MI,
    Lewis Publishers, Inc., pp. 392-393.

    Hrotmatka O, Polesofsky W (1962) Untersuchungen uber die Essiggarung.
    VII. Uber die Oxydation verschiedener primarer Alkohole und Glykole.
     Enzymologia, 24:372-384.

    HSDB (1998)  Hazardous substances data bank. Micromedex Inc. (CD-ROM
    version).

    IPCS (1993)  International Chemical Safety Card -- Ethylene glycol.
    Geneva, World Health Organization, International Programme on
    Chemical Safety (ICSC 0270).

    Jank BE, Guo HM, Cairns VW (1974) Activated sludge treatment of
    airport wastewater containing de-icing fluids.  Water research,
    8:875-880.

    Japan Environment Agency (1991)  Chemicals in the environment. Report
     on environmental survey and wildlife monitoring of chemicals in FY
     1988 and 1989. Tokyo, Japan Environment Agency, Department of
    Environmental Health, Office of Health Studies.

    Kahru A, Tomson K, Pall T, Kulm I (1996) Study of toxicity of
    pesticides using luminescent bacteria  Photobacterium phosphoreum.
     Water science and technology, 33(6):147-154.

    Kaiser KLE, Palabrica VS (1991)  Photobacterium phosphoreum toxicity
    data index.  Water pollution research journal of Canada, 26:361-431.

    Kameya T, Murayama T, Urano K, Kitano M (1995) Biodegradation ranks of
    priority organic compounds under anaerobic conditions.  Science of the
     total environment, 170:43-51.

    Kaushal R, Walker TK (1951) Formation of cellulose by certain species
    of  Acetobacter. Biochemical journal, 48:618-621.

    Kent JA, ed. (1974)  Riegel's handbook of industrial chemistry, 7th
    ed. New York, NY, Van Nostrand Reinhold Company.

    Khoury GA, Abdelghani AA, Anderson AC, Monkiedje A (1990) Acute
    toxicity of ethylene glycol to crayfish, bluegill sunfish and soil
    micro-organisms.  Trace substances in environmental health, 
    23:371-378.

    Khoury GA, Adbelghani AA, Anderson AC (1993) Bioaccumulation and
    depuration of ethylene glycol by crayfish  (Procambarus spp.).
     Environmental toxicology and water quality, 8:25-31.

    Kilroy AC, Gray NF (1992) Toxicity of four organic solvents commonly
    used in the pharmaceutical industry to activated sludge.  Water
     research, 26:887-892.

    Klecka GM, Carpenter CL, Landenberger BD (1993) Biodegradation of
    aircraft deicing fluids in soil at low temperatures.  Ecotoxicology
     and environmental safety, 25:280-295.

    Konnemann H (1981) Quantitative structure-activity relationships in
    fish toxicity studies. I. Relationship for 50 industrial pollutants.
     Toxicology, 19:209-221.

    LDOTD (1990)  Fate of ethylene glycol in the environment. Baton
    Rouge, LA, Louisiana Department of Transportation and Development,
    Louisiana Transportation Research Center.

    Lee NE, Haag WR, Jolley RL (1983) Cooling water pollutants:
    bioaccumulation by  Corbicula. In:  Jolley RL, Brungs WA, Cotruvo
    JA, Cumming RB, Mattice JS, Jacobs VA, eds.  Water chlorination:
     Chemistry, environmental impact and health effects. Vol. 4. Ann
    Arbor, MI, Ann Arbor Science Publishers, pp. 851-870.

    Lipnick RL, ed. (1991)  Studies of narcosis. London, Chapman and
    Hall, pp. 123-124.

    Lokke H (1984) Leaching of ethylene glycol and ethanol in subsoils.
     Water, air, and soil pollution, 22:373-387.

    Lyman WJ, Reehl WF, Rosenblatt DH (1982)  Handbook of chemical
     property estimation methods. New York, NY, McGraw-Hill.

    Masters JA, Lewis MA, Davidson DH, Bruce RD (1991) Validation of a
    4-day  Ceriodaphnia toxicity test and statistical considerations in
    data analysis.  Environmental toxicology and chemistry, 10:47-55.

    Matsui S, Murakami T, Sasaki T, Hirose Y, Iguma Y (1975) Activated
    sludge degradability of organic substances in the waste water of the
    Kashima petroleum and petrochemical industrial complex in Japan.
     Progress in water technology, 7(3-4):645-650.

    Mayer FL, Ellersieck MR (1986)  Manual of acute toxicity:
     interpretation and database for 410 chemicals and 66 species of
     freshwater animals. Washington, DC, US Department of the Interior,
    Fish and Wildlife Service (Resource Publication No. 160).

    Mayes MA, Alexander HC, Dill DC (1983) A study to assess the influence
    of age on the response of fathead minnows in static acute toxicity
    tests.  Bulletin of environmental contamination and toxicology,
    31:139-147.

    McGahey C, Bouwer EJ (1992) Biodegradation of ethylene glycol in
    simulated subsurface environments.  Water science and technology,
    26:41-49.

    Means JL, Anderson SJ (1981) Comparison of five different methods for
    measuring biodegradability in aqueous environments.  Water, air, and
     soil pollution, 16:301-315.

    Nielsen IR, Malcolm HM, Dobson S (1993)  Environmental hazard
     assessment: Ethylene glycol. Garston, United Kingdom Department of
    the Environment, Building Research Establishment, Toxic Substances
    Division. 33 pp. (TSD/16).

    Nishiushi Y (1984) Toxicity of agrochemicals to freshwater organisms.
    III. Solvents.  Suisan Zoshoku, 32:115-119.

    Pillard DA (1995) Comparative toxicity of formulated glycol de-icers
    and pure ethylene and propylene glycol to  Ceridaphnia dubia and
     Pimephales promelas.  Environmental toxicology and chemistry,
    14:311-315.

    Pitt WW, Jolley RL, Scott CD (1975) Determination of trace organics in
    municipal sewage effluents and natural waters by high resolution ion
    exchange chromatography.  Environmental science and technology,
    9:1068-1073.

    Pitter P (1976) Determination of biological degradability of organic
    substances.  Water research, 10:231-235.

    Price KS, Waggy GT, Conway RA (1974) Brine shrimp bioassay and
    seawater BOD of petrochemicals.  Journal of the Water Pollution
     Control  Federation, 46(1):63-77.

    Riddell C, Nielsen SW, Kersting EJ (1967) Ethylene glycol poisoning in
    poultry.  Journal of the American Veterinary Medical Association,
    150:1531-1535.

    Ross D, Stroo HF, Bourquin AW, Sikes DJ (1988) Bioremediation of
    hazardous waste sites in the USA: case histories. In:  Proceedings of
     the American Pollution Control Association Annual Meeting (Paper
    88-6B.2, 81, 9s).

    Schramm M, Warrick AW, Fuller WH (1986) Permeability of soils to four
    organic liquids and water.  Hazardous waste and hazardous materials,
    3:21-27.

    Sills RD, Blakeslee PA (1992) The environmental impact of deicers in
    airport stormwater runoff. In:  Chemical deicers and the environment.
    Boca Raton, FL, Lewis Publishers, pp. 323-340.

    SRI (1993)  Directory of chemical producers -- United States of
     America. Menlo Park, CA, Stanford Research Institute International
    (598; 890).

    Steffens GL, Barer SJ (1984) The inhibition of axillary and terminal
    bud growth on tobacco by a series of C2 to C10 diol formulations.
     Beitrage zur Tabakforschung International, 12:279-284.

    Stowe CM, Barnes DM, Arendt TD (1981) Ethylene glycol intoxication in
    ducks.  Avian diseases, 25:538-541.

    Tsuji S, Tonogai Y, Ito Y, Kanoh S (1986) The influence of rearing
    temperature on the toxicity of various environmental pollutants for
    killifish  (Oryzias latipes). Eisei Kagaku, 32:46-53.

    US EPA (1980)  Organic chemical manufacturing. Vol. 9: Selected
     processes. Prepared by R.J. Lovell et al., US Environmental
    Protection Agency (Report No. EPA-450/3-80-028d).

    Watson GK, Jones N (1977) The biodegradation of polyethylene glycols
    by sewage bacteria.  Water research, 11:95-100.

    Willetts A (1981) Bacterial metabolism of ethylene glycol.
     Biochimica Biophysica Acta, 677(2):194-199.

    Yoshida M, Hoshii H, Morimoto H (1969) Nutritive values of glycols for
    poultry feeds . Japanese poultry science, 6:73-81.

    Zahn R, Wellens H (1980) Prufung der biologischen Abbaubarkeit im
    Standversuch - weitere Erfahrungen und neue Einsatzmoglichkeiten.
     Zeitschrift fuer Wasser und Abwasser Forschung, 13:1-7.

    Zeithoun MA, McIllhenny WF (1971)  Treatment of wastewater from the
     production of polyhydric organics. Produced for the US Environmental
    Protection Agency (PB-213841).
    

    APPENDIX 1 -- SOURCE DOCUMENTS

    Nielsen IR, Malcolm HM, Dobson S (1993)  Environmental hazard
     assessment: Ethylene glycol. Garston, United Kingdom Department of
    the Environment, Building Research Establishment, Toxic Substances
    Division (TSD/16)

         The first draft of the Environmental Hazard Assessment (EHA)
    documents are extensively circulated both within the United Kingdom
    and internationally for peer review. Comments received are dealt with
    in the final published version. For this EHA document on ethylene
    glycol, comments were received from the United Kingdom Department of
    the Environment (Wastes Technical Division and Global Atmosphere
    Division), the Health and Safety Executive (United Kingdom), the
    Ministry of Agriculture, Fisheries and Food (United Kingdom), the
    Water Research Centre (United Kingdom), The Edinburgh Centre for
    Toxicology, Heriot-Watt University, the US Environmental Protection
    Agency, the Swedish National Chemicals Inspectorate, the
    Umweltbundesamt, Germany, and ICI Chemicals and Polymers Ltd.

    BUA (1991)  Ethylene glycol. GDCh-Advisory Committee on Existing
    Chemicals of Environmental Relevance (BUA). Hirzel, Wissenschaftliche
    Verlagsgesellschaft (BUA Report 92.S)

         For the BUA review process, the company that is in charge of
    writing the report (usually the largest producer in Germany) prepares
    a draft report using literature from an extensive literature search as
    well as internal company studies. This draft is subject to a peer
    review during several readings of a working group consisting of
    representatives from government agencies, the scientific community,
    and industry.

         The English translation of this report was published in 1994.
    

    APPENDIX 2 -- CICAD PEER REVIEW

         The draft CICAD on ethylene glycol was sent for review to
    institutions and organizations identified by IPCS after contact with
    IPCS national Contact Points and Participating Institutions, as well
    as to identified experts. Comments were received from:

         Chemical Manufacturers' Association, Arlington, USA

         Chinese Academy of Preventive Medicine, Beijing, People's
         Republic of China

         European Chemical Industry Council (CEFIC), Brussels, Belgium

         Health and Safety Executive, Bootle, United Kingdom

         Health Department of Western Australia, Perth, Australia

         National Institute of Health Sciences, Tokyo, Japan

         National Institute of Public Health, Prague, Czech Republic

         Senatskommission der Deutschen Forschungsgemeinschaft, Bonn,
         Germany

         United States Department of Health and Human Services (National
         Institute of Environmental Health Sciences, Research Triangle
         Park), USA

         United States Environmental Protection Agency (Region VIII;
         National Center for Environmental Assessment, Washington, DC),
         USA

         World Health Organization/International Programme on Chemical
         Safety, Montreal, Canada
    

    APPENDIX 3 -- CICAD FINAL REVIEW BOARD

    Washington, DC, USA, 8-11 December 1998

    Members

    Dr T. Berzins, National Chemicals Inspectorate (KEMI), Solna, Sweden
     (Vice-Chairperson)

    Mr R. Cary, Toxicology Unit, Health Directorate, Health and Safety
    Executive, Bootle, Merseyside, United Kingdom  (Rapporteur)

    Dr S. Dobson, Institute of Terrestrial Ecology, Monks Wood, Abbots
    Ripton, Huntingdon, Cambridgeshire, United Kingdom

    Dr O. Faroon, Agency for Toxic Substances and Disease Registry,
    Centers for Disease Control and Prevention, Atlanta, GA, USA

    Dr G. Foureman, National Center for Environmental Assessment, US
    Environmental Protection Agency, Research Triangle Park, NC, USA

    Dr H. Gibb, National Center for Environmental Assessment, US
    Environmental Protection Agency, Washington, DC, USA  (Chairperson)

    Dr R.F. Hertel, Federal Institute for Health Protection of Consumers &
    Veterinary Medicine, Berlin, Germany

    Dr I. Mangelsdorf, Documentation and Assessment of Chemicals,
    Fraunhofer Institute for Toxicology and Aerosol Research, Hanover,
    Germany

    Dr A. Nishikawa, Division of Pathology, National Institute of Health
    Sciences, Tokyo, Japan

    Dr E.V. Ohanian, Office of Water/Office of Science and Technology,
    Health and Ecological Criteria Division, US Environmental Protection
    Agency, Washington, DC, USA

    Dr J. Sekizawa, Division of Chem-Bio Informatics, National Institute
    of Health Sciences, Tokyo, Japan

    Professor P. Yao, Institute of Occupational Medicine, Chinese Academy
    of Preventive Medicine, Ministry of Health, Beijing, People's Republic
    of China

    Observers

    Dr K. Austin, National Center for Environmental Assessment, US
    Environmental Protection Agency, Washington, DC, USA

    Dr I. Daly (ICCA representative), Regulatory and Technical Associates,
    Lebanon, NJ, USA

    Ms K.L. Lang (CEFIC, European Chemical Industry Council,
    representative), Shell International, London, United Kingdom

    Ms K. Roberts (ICCA representative), Chemical Self-funded Technical
    Advocacy and Research (CHEMSTAR), Chemical Manufacturers Association,
    Arlington, VA, USA

    Dr W. Snellings (ICCA representative), Union Carbide Corporation,
    Danbury, CN, USA

    Dr M. Sweeney, Document Development Branch, National Institute for
    Occupational Safety and Health, Cincinnati, OH, USA 

    Dr K. Ziegler-Skylakakis, GSF-Forschungszentrum für Umwelt und
    Gesundheit GmbH, Institut für Toxikologie, Oberschleissheim, Germany

    Secretariat

    Dr M. Baril, Institut de Recherches en Santé et Sécurité du Travail du
    Québec (IRSST), Montreal, Quebec, Canada

    Dr H. Galal-Gorchev, Chevy Chase, MD, USA

    Ms M. Godden, Health and Safety Executive, Bootle, Merseyside, United
    Kingdom

    Dr R.G. Liteplo, Environmental Health Directorate, Health Canada,
    Ottawa, Ontario, Canada

    Ms L. Regis, Programme for the Promotion of Chemical Safety, World
    Health Organization, Geneva, Switzerland

    Mr A. Strawson, Health and Safety Executive, London, United Kingdom

    Dr P. Toft, Programme for the Promotion of Chemical Safety, World
    Health Organization, Geneva, Switzerland
    

    RÉSUMÉ D'ORIENTATION

         Ce CICAD relatif aux problèmes d'ordre écologique posés par
    l'éthylène-glycol a été préparé par l'Institut d'Ecologie terrestre
    (Royaume-Uni) sur la base d'un rapport intitulé  Environmental hazard
     assessment:  Ethylene glycol (Nielsen et al., 1993). Le rapport sur
    l'éthylène-glycol rédigé par le Comité consultatif de la Société
    allemande de Chimie pour les produits chimiques qui posent des
    problèmes écologiques (BUA, 1991) a également été utilisé comme source
    de données. Parallèlement, il a été procédé à un dépouillement de la
    littérature récente (jusqu'en 1998).On trouvera à l'appendice 1 des
    indications sur la méthode utilisée par les pairs pour examiner les
    principales sources documentaires. Les renseignements concernant
    l'examen du CICAD par les pairs font l'objet de l'appendice 2. Ce
    CICAD a été approuvé en tant qu'évaluation internationale lors de la
    réunion du Comité d'évaluation finale qui s'est tenue à Washington du
    8 au 11 décembre 1998. La liste des participants à cette réunion
    figure à l'appendice 3. La fiche d'information internationale sur la
    sécurité chimique (ICSC No 0270) relative à l'éthylène-glycol, établie
    par le Programme international sur la sécurité chimique (IPCS, 1993)
    est également reproduite dans ce document.

         L'éthylène-glycol (No CAS 107-21-1) se présente sous la forme
    d'un liquide limpide, incolore et sirupeux, de saveur sucrée mais
    dépourvu d'odeur. Il est peu volatil. Il est miscible à l'eau et à
    certains autres solvants, légèrement soluble dans l'éther mais
    pratiquement insoluble dans le benzène, les hydrocarbures chlorés,
    l'éther de pétrole et les huiles. Son coefficient de partage entre
    l'octanol et l'eau (log  Kow) est compris entre -1,93 et -1,36.

         On estime que la capacité de production mondiale était de 9,4
    millions de tonnes en 1993. La libération d'éthylène-glycol dans
    l'environnement se produit principalement au niveau de l'hydrosphère.
    Localement, c'est par suite de l'utilisation du composé dans les
    aéroports pour dégivrer les pistes et les avions que les décharges
    dans l'environnement devraient être les plus importantes. Dans
    l'ensemble du monde, environ les deux tiers de la production
    d'éthylène-glycol sont utilisés comme intermédiaire dans la
    préparation d'autres composés et à peu près un quart comme antigel
    pour moteurs.

         L'éthylène-glycol libéré dans l'atmosphère subit une
    décomposition par suite de sa réaction sur les radicaux hydroxyle;
    dans ces conditions, sa demi-vie se situe entre 0,3 et 3,5 jours.

         Il ne devrait pas subir d'hydrolyse dans les eaux de surface.

         Il a peu, voire pas de propension à se fixer aux particules et
    présente une certaine mobilité pédologique.

         La faible valeur de son coefficient de partage entre l'octanol et
    l'eau et de son facteur de bioconcentration dans un certain nombre
    d'organismes fait présager une tendance peu marquée à la
    bioaccumulation.

         Les tests habituels sur boues d'égouts révèlent une bonne
    biodégradabilité. De nombreuses études montrent qu'il y a
    biodégradation en aérobiose comme en anaérobiose. Selon certains
    travaux, la biodégradation est retardée, mais selon d'autres elle ne
    l'est pas. La décomposition se produit dans les boues adaptées comme
    dans celles qui ne le sont pas. On a fait état d'une décomposition
    rapide dans les eaux de surface (moindre dans l'eau salée que dans
    l'eau douce), les eaux souterraines et les inoculums de sol. Certaines
    souches de microorganismes sont capables d'utiliser l'éthylène-glycol
    comme source de carbone.

         On n'a guère de données sur les concentrations mesurées dans les
    divers compartiments de l'environnement. Dans les eaux superficielles,
    la concentration d'éthylène-glycol est généralement faible, de l'ordre
    de quelques microgrammes par litre. Dans des effluents industriels
    provenant d'unités de production, on a mesuré des concentrations avant
    traitement allant jusqu'à 1 300 mg/litre en moyenne. Les
    concentrations de loin les plus élevées sont celles que l'on trouve
    dans les eaux de ruissellement des aéroports, avec des valeurs qui
    peuvent atteindre 19 000 mg/litre.

         L'éthylène-glycol est généralement peu toxique pour les
    organismes aquatiques. Pour les microorganismes, le seuil de toxicité
    est supérieur à 1 000 mg/litre. Dans le cas des algues microscopiques,
    la CE50 relative à la croissance est supérieure ou égale à 6 500
    mg/litre. Les tests de toxicité aiguë sur invertébrés aquatiques dont
    on a pu tirer une valeur, montrent que la CL50 se situe au-delà de 20
    000 mg/litre; ceux qui ont été pratiqués sur des poissons donnent des
    valeurs supérieures à 17 800 mg/litre. Un test sur amphibien a montré
    que la CL50 pour les têtards était égale à 17 000 mg/litre. Les
    études de toxicité chronique portant sur la reproduction des daphnies
    ont permis de fixer à 8 590 mg/litre la concentration sans effet
    observable (NOEC). En prenant la croissance pour critère, on a obtenu
    une NOEC de 15 380 mg/litre pour des poissons brièvement exposés.

         Les tests effectués avec des dégivrants à base d'éthylène-glycol
    montrent que ces produits sont plus toxiques pour les organismes
    aquatiques que l'éthylène-glycol pur, ce qui indique que ces
    dégivrants contiennent d'autres substances toxiques.

         Lors de tests de laboratoire comportant l'exposition d'organismes
    aquatiques à l'eau d'une rivière recevant les eaux de ruissellement
    d'un aéroport, on a constaté des effets toxiques pouvant aller jusqu'à
    la mort. Des études effectuées sur le terrain à proximité d'un
    aéroport ont révélé que les organismes aquatiques présentaient des

    signes d'intoxication qui pourraient être dus à l'éthylène-glycol,
    avec en outre présence de poissons morts et réduction de la
    biodiversité. Il n'est toutefois pas absolument certain que ces effets
    puissent être attribués à l'éthylène-glycol.

         Les organismes terrestres ont beaucoup moins de chances d'être
    exposés à de l'éthylène-glycol et ils sont généralement peu sensibles
    à ce composé. Il a fallu des concentrations supérieures à 100 000
    mg/litre pour produire des effets toxiques sur des champignons et des
    levures prélevés dans le sol. On a pu provoquer une inhibition de la
    germination en plongeant des semences dans des bains contenant une
    très forte concentration d'éthylène-glycol, mais ces résultats n'ont
    aucune signification sur le plan écologique. Chez des canards ayant
    reçu de l'éthylène-glycol par voie digestive, la dose sans effet
    observable (NOEL) se situait à 1221 mg/kg de poids corporel; pour les
    poulets, la dose létale serait d'environ 8 000 mg/kg p.c. Ces valeurs
    montrent que le composé est peu toxique pour les volatiles.
    

    RESUMEN DE ORIENTACION

         El presente CICAD sobre los aspectos ambientales del
    etilenglicol, preparado por el Instituto de Ecología Terrestre del
    Reino Unido se basa en el informe de Evaluación de los peligros para
    el medio ambiente: Etilenglicol (Nielsen  et al., 1993). Se utilizó
    también como documento original el informe sobre el etilenglicol que
    había preparado el Comité Consultivo sobre Sustancias Químicas
    Importantes para el Medio Ambiente de la Sociedad Alemana de Química
    (BUA, 1991). Además de usar estos documentos, se realizó una búsqueda
    de la bibliografía reciente hasta 1998. La información acerca del
    carácter del proceso de examen colegiado para los principales
    documentos originales figura en el apéndice 1. La información relativa
    al examen colegiado de este CICAD se presenta en el apéndice 2. Su
    aprobación como evaluación internacional se realizó en una reunión de
    la Junta de Evaluación Final, celebrada en Washington, DC, Estados
    Unidos, los días 8-11 de diciembre de 1998. La lista de participantes
    en esta reunión figura en el apéndice 3. La Ficha internacional de
    seguridad química (ICSC 0270), preparada por el Programa Internacional
    de Seguridad de las Sustancias Químicas (IPCS, 1993), también se
    reproduce en el presente documento.

         El etilenglicol (CAS No 107-21-1) es un líquido denso, claro,
    incoloro, de sabor dulce, pero inodoro. Tiene una volatilidad baja. Es
    miscible con el agua y algunos otros disolventes, ligeramente soluble
    en éter, pero prácticamente insoluble en benceno, hidrocarburos
    clorados, éteres de petróleo y aceites. El log del coeficiente de
    reparto octanol/agua oscila entre -1,93 y -1,36.

         La capacidad de producción mundial estimada en 1993 fue de 9,4
    millones de toneladas. La liberación en el medio ambiente se produce
    fundamentalmente en la hidrosfera. La liberación local más importante
    a las aguas superficiales es consecuencia de la utilización de
    etilenglicol como descongelante en las pistas de los aeropuerto y en
    los aviones. Unos dos tercios de la producción mundial de etilenglicol
    se utilizan como intermediario químico, con otra cuarta parte como
    anticongelante en los refrigerantes de los motores.

         El etilenglicol que se libera en la atmósfera se degrada por
    reacción con radicales hidroxilo; la semivida del compuesto en esta
    reacción se ha calculado entre 0,3 y 3,5 días.

         No se prevé que haya hidrólisis del etilenglicol en aguas
    superficiales.

         El compuesto tiene poca o ninguna capacidad de unión a partículas
    y es móvil en el suelo.

         El bajo coeficiente de reparto octanol/agua y los factores de
    bioacumulación medidos en un pequeño número de organismos indican una
    capacidad escasa de bioacumulación.

         El etilenglicol es fácilmente biodegradable en pruebas
    normalizadas utilizando lodos cloacales. En numerosos estudios se ha
    puesto de manifiesto su biodegradación en condiciones tanto aerobias
    como anaerobias. Algunos estudios parecen indicar una fase
    estacionaria antes de la degradación, pero otros muchos no. Se produce
    degradación tanto en lodos adaptados como no adaptados. Se ha
    notificado una degradación rápida en las agua superficiales (inferior
    en la salada que en la dulce), el agua freática y los inóculos del
    suelo. Se han identificado varias cepas de microorganismos capaces
    utilizar el etilenglicol como fuente de carbono.

         Se dispone de datos limitados sobre las concentraciones de
    etilenglicol medidas en los compartimentos del medio ambiente. Los
    niveles medidos en las aguas superficiales generalmente han sido
    bajos, de algunos microgramos por litro. Las concentraciones en las
    aguas residuales de instalaciones de producción antes del tratamiento
    han alcanzado un promedio de hasta 1 300 mg/litro. Las concentraciones
    con diferencia más altas de las notificadas corresponden al agua de
    escorrentía de los aeropuertos, con concentraciones de hasta 19 000
    mg/litro.

         El etilenglicol suele tener una toxicidad baja para los
    organismos acuáticos. El umbral tóxico para los microorganismos es
    superior a 1 000 mg/litro. Las CE50 para el crecimiento en las
    microalgas son de 6 500 mg/litro o superiores. En las pruebas de
    toxicidad aguda con invertebrados acuáticos en las que se pudo
    determinar un valor se obtuvieron CL50 superiores a 20 000 mg/litro,
    y con peces por encima de 17 800 mg/litro. En una prueba realizada con
    anfibios se observó una CL50 para los renacuajos de 17 000 mg/litro.
    Se ha notificado una concentración sin efectos observados (NOEC) para
    pruebas crónicas en dáfnidos de 8 590 mg/litro (para los efectos
    finales reproductivos). Tras una exposición breve de peces se notificó
    una NOEC para el crecimiento de 15 380 mg/litro.

         En pruebas en las que se utilizó descongelante que contenía
    etilenglicol se puso de manifiesto una toxicidad para los organismos
    acuáticos superior a la observada con el compuesto puro, lo que indica
    la presencia de otros componentes tóxicos en las formulaciones.

         En pruebas de laboratorio de exposición de organismos acuáticos a
    una corriente de agua receptora de la escorrentía de los aeropuertos
    aparecieron efectos tóxicos y letales. En estudios sobre el terreno
    realizados en las cercanías de un aeropuerto se han notificado signos
    tóxicos compatibles con la intoxicación por etilenglicol, muerte de
    peces y reducción de la biodiversidad. Estos efectos no se pueden
    atribuir de manera definitiva al etilenglicol.

         Es mucho menos probable que los organismos terrestres estén
    expuestos al etilenglicol y en general muestran una sensibilidad baja
    al compuesto. Se necesitaron concentraciones superiores a 100 000
    mg/litro para producir efectos tóxicos en levaduras y hongos del
    suelo. En algunos experimentos se observó que las concentraciones muy
    altas y la impregnación de las semillas inhibían la germinación; estos
    efectos no se consideran importantes para el medio ambiente. La
    concentración sin efectos observados (NOEL) para patos a los que se
    administró por vía oral 1 221 mg/kg de peso corporal y las dosis
    letales notificadas para aves de corral de alrededor de 8 000 mg/kg de
    peso corporal indican una toxicidad baja para las aves.
    


    See Also:
       Toxicological Abbreviations