2-Methoxyethanol
(2-ME), 2-Ethoxyethanol (2-EE), and 2-Butoxyethanol (2-BE)
Listed on the Second Priority Substances List (PSL2)
2-Methoxyethanol and 2-Butoxyethanol are considered to be CEPA toxic and
have been added to the List of Toxic Substances 2-Ethoxyethanol is not
considered to be CEPA toxic
2-Methoxyethanol, 2-ethoxyethanol, and 2-butoxyethanol are one of
25 substances or groups of substances placed on the Second
Priority Substances List (PSL2) to determine whether they posed a
significant risk to the environment in Canada or to the health of Canadians.
Assessment Status and Conclusion
Environment Canada and Health Canada completed the assessments of
2-methoxyethanol, 2-ethoxyethanol, and 2-butoxyethanol.
The scientific assessments indicate that 2-methoxyethanol and 2-butoxyethanol
are both entering the environment in a quantity or concentration or under
conditions that constitute or may constitute a danger in Canada to human
life or health, and therefore are considered to be CEPA toxic.
The proposed Order to add 2-methoxyethanol and 2-butoxyethanol to the
List of Toxic Substances in Schedule 1 of CEPA 1999 was published in the
Canada Gazette, Part I, on October 25th, 2003. No comments or Notices
of Objection were received during the 60-day public comment period following
the publication of the proposed Order.
Based on the considerations in the assessment, 2-ethoxyethanol does not
pose a danger to either the environment or to human life or health in
Canada, and therefore, it is not considered to be CEPA toxic.
Related Information
The public comment period on the draft assessment reports for 2-methoxyethanol,
2-ethoxyethanol, and 2-butoxyethanol began on August 19th, 2000, and ended
on October 18th, 2000. There were no comments provided related to 2-methoxyethanol
assessment.
Summary of Public Comments on 2-Butoxyethanol Draft Assessment Report
in HTML and PDF
Summary of Public Comments on 2-Ethoxyethanol Draft Assessment Report
in HTML and PDF
Risk Management - Please refer to the Management of Toxic Substances
website for the Risk Management of 2-methoxyethanol
and 2-butoxyethanol.
Publications
PSL1 Report on 2-Methoxyethanol (2002) in HTML
and PDF
PSL1 Report on 2-Ethoxyethanol (2002) in HTML
and PDF
PSL1 Report on 2-Butoxyethanol (2002) in HTML
and PDF,
and Addendum (2003) in HTML
and PDF
To obtain a paper copy of any report listed above, please contact the Inquiry
Centre of Environment Canada at:
Synopsis of 2-Methoxyethanol Assessment Report (2002)
2-Methoxyethanol is not commercially produced in Canada. It is imported for use mainly as a
chemical processing aid and as a component of formulated products. The use of 2-methoxyethanol has
declined over the past few years because it has been partially replaced in some countries by other
substances. All reported environmental releases are to the atmosphere.
2-Methoxyethanol reacts with hydroxyl radicals in the air with a half-life of about 18 hours.
Much of the 2-methoxyethanol released to the atmosphere is predicted to remain in air, but a
substantial proportion would partition to water and to soil. 2-Methoxyethanol is biodegraded
in surface water and aerobic soil with an estimated half-life of 1-4 weeks. It is somewhat more
persistent under aerobic conditions. 2-Methoxyethanol has a very low octanol/water partition
coefficient and is therefore not expected to bioaccumulate to any significant degree. There
are very few available data on concentrations of 2-methoxyethanol in the environment in Canada
or elsewhere.
Data on toxicity exist for aquatic organisms, including microorganisms, invertebrates and fish.
2-Methoxyethanol is not very toxic to these organisms; in a number of studies, the LC50 was
above the highest concentration tested.
Because of the paucity of environmental monitoring data, exposure values for the environmental
assessment were estimated based on modelling. Estimated environmental concentrations of
2-methoxyethanol are several orders of magnitude lower than the adverse effects thresholds
calculated for sensitive organisms.
2-Methoxyethanol is not involved in stratospheric ozone depletion and is not an important
contributor to climate change or ground-level ozone formation.
Based on a relatively extensive database in experimental animals, 2-methoxyethanol has
consistently been associated with a wide range of adverse effects on health, including
those considered to be severe and irreversible (e.g., teratogenicity), with some occurring
at relatively low levels of exposure. However, although relevant data are limited, exposure
of the general population through environmental media is expected to be small, due to reported
declining use of the compound in recent years as it is replaced with less hazardous compounds.
Margins between worst-case estimates of exposure from environmental media and lowest effect
levels for developmental toxicity obtained in toxicological investigations in experimental
animals are large. However, available data are insufficient to conclude that margins between
worst-case estimates of exposure in consumer products and lowest effect levels are adequate.
Based on these considerations, it is concluded that 2-methoxyethanol is not entering the
environment in a quantity or concentration or under conditions that have or may have an
immediate or long-term harmful effect on the environment or its biological diversity or
that constitute or may constitute a danger to the environment on which life depends. On
the basis principally of its high health hazard potential, 2-methoxyethanol may be entering
the environment in a quantity or concentration or under conditions that constitute or may
constitute a danger in Canada to human life or health. Therefore, 2-methoxyethanol is
considered to be "toxic" under Section 64 of the Canadian Environmental Protection Act, 1999
(CEPA 1999).
It is recommended that additional information be acquired on patterns of use of 2-methoxyethanol
in Canada, particularly in relation to its presence in consumer products. It is further
recommended that, in view of the profile of toxicity of 2-methoxyethanol, potential for exposure
of the general population to this compound be eliminated or reduced to the extent possible.
Synopsis of 2-Ethoxyethanol
Assessment Report (2002)
2-Ethoxyethanol is not commercially produced in Canada. It is imported for use mainly as a
component of formulated products. All environmental releases are reported to be to the atmosphere.
Some 2-ethoxyethanol is also sent to landfills and other waste disposal sites.
2-Ethoxyethanol reacts with hydroxyl radicals in the air with a half-life of about 0.2-4 days.
Much of the 2-ethoxyethanol released to the atmosphere is predicted to remain in air, but a
substantial proportion would partition to water and to soil. 2-Ethoxyethanol is biodegraded in
surface water and aerobic soil with an estimated half-life of 1-4 weeks. It is somewhat more
persistent under anaerobic conditions. 2-Ethoxyethanol has a very low octanol/water partition
coefficient and is therefore not expected to bioaccumulate to any significant degree. There are
very few available data on concentrations of 2-ethoxyethanol in the environment in Canada or
elsewhere.
Data on toxicity exist for aquatic organisms, including microorganisms, invertebrates
and fish. 2-Ethoxyethanol is not very toxic to these organisms; in a
number of studies, the LC50 was above the highest concentration
tested.
Exposure values for air were based on limited Canadian monitoring data. Because of the paucity
of environmental monitoring data, exposure values for soil and water were estimated based on
fugacity modelling. Estimated environmental concentrations of 2-ethoxyethanol are several orders
of magnitude lower than the adverse effects thresholds calculated for sensitive organisms.
2-Ethoxyethanol is not involved in stratospheric ozone depletion and is not an important contributor
to climate change or ground-level ozone formation.
2-Ethoxyethanol has consistently induced hematological, reproductive (effects on testes and sperm
parameters) and developmental effects in multiple species of experimental animals exposed by
various routes. In addition, there is some limited evidence of effects on the blood and reduced
sperm production in occupationally exposed human populations. Although monitoring data are very
limited, the margins between upper-bounding estimates of exposure to 2-ethoxyethanol in the general
environment and conservative effect levels for critical effects are large. Limited available data
do not indicate that 2-ethoxyethanol is commonly present in consumer products in Canada. However,
upper-bounding estimates of exposure to 2-ethoxyethanol through use of some consumer products
containing the substance may approach or exceed these conservative effect levels, although the
degree of confidence in the estimates of exposure from consumer products is considered to be
extremely low.
Based on these considerations, it is concluded that 2-ethoxyethanol is not entering the environment
in a quantity or concentration or under conditions that have or may have an immediate or long-term
harmful effect on the environment or its biological diversity or that constitute or may constitute
a danger to the environment on which life depends. Based on comparison of upper-bounding estimates
of exposure in the general environment with conservative effect levels, it is concluded that
2-ethoxyethanol is not entering the environment in a quantity or concentration or under conditions
that constitute or may constitute a danger in Canada to human life or health. Therefore,
2-ethoxyethanol is not considered to be "toxic" as defined in Section 64 of the Canadian
Environmental Protection Act, 1999 (CEPA 1999).
Although 2-ethoxyethanol was not detected in emissions from a range of consumer products in
Canada, acquisition of additional more representative information on its use in consumer
products in Canada is desirable.
Synopsis of 2-Butoxyethanol
Assessment Report (2002)
2-Butoxyethanol is not commercially produced in Canada. It is imported for use mainly as a
component of formulations, as part of consumer products or manufactured articles, and as a chemical
processing aid. Most reported environmental releases are to the atmosphere, with some minor
releases to water.
2-Butoxyethanol reacts with hydroxyl radicals in the air with a half-life of a few hours to
about a day. Most of the 2-butoxyethanol released to the atmosphere is predicted to remain in
air, with some partitioning to water and soil. 2-Butoxyethanol is biodegraded in water and
soil, with an estimated half-life of 1-4 weeks. It has a low octanol/water partition
coefficient and is therefore not expected to bioaccumulate to any significant degree. Only
limited data are available on concentrations of 2-butoxyethanol in the environment in Canada or
elsewhere.
Data on toxicity were identified for aquatic organisms, including microorganisms,
invertebrates and fish. The most sensitive species reported, based on
acute exposure, is the grass shrimp (Palaemonetes pugio).
Because of the limitations of environmental monitoring data, exposures for environmental
compartments other than air were estimated based on modelling. Estimated environmental
concentrations of 2-butoxyethanol are a few orders of magnitude less than the adverse effects
thresholds calculated for sensitive organisms.
2-Butoxyethanol is not involved in stratospheric ozone depletion and is not an important
contributor to climate change or ground-level ozone formation.
Based on the limited data identified, inhalation of 2-butoxyethanol in air is an important route
of exposure, with estimated exposure through use of consumer products containing the substance
being considerable. No data were identified concerning the contribution of food to overall
exposure to 2-butoxyethanol.
Based primarily on investigations in experimental animals, the principal critical health effects
associated with exposure to 2-butoxyethanol are alterations in hematological parameters
associated with hemolysis. Tolerable Concentrations for these effects and for lesions of the
forestomach in mice, for which information on mode of action is inadequate to preclude their
relevance to humans, were developed, based on Benchmark Concentrations. A Tolerable
Concentration is the level of intake to which it is believed a person may be exposed daily
over a lifetime without deleterious effect.
Levels of 2-butoxyethanol in ambient air in Canada are less than the Tolerable Concentrations
derived for effects on the blood or forestomach. However, exposure to 2-butoxyethanol during
use of products containing the substance could potentially exceed the Tolerable Concentrations,
based on limited data on emissions from products currently available in Canada.
Based on available data, it is concluded that 2-butoxyethanol is not entering the environment in
a quantity or concentration or under conditions that have or may have an immediate or long-term
harmful effect on the environment or its biological diversity; or constitute or may constitute a
danger to the environment on which life depends. 2-Butoxyethanol is considered to be entering
the environment in a quantity or concentration or under conditions that constitute or may
constitute a danger in Canada to human life or health. Therefore, 2-butoxyethanol is considered
to be "toxic" as defined in Section 64 of CEPA 1999.
Additional characterization of the ranges and distributions of concentrations of 2-butoxyethanol
in consumer products currently available in Canada and their emissions is considered a clear
priority as a basis for risk management.
Disclaimer: Although care has been taken to ensure that the information found on this website accurately reflects the requirements prescribed in the Canadian Environmental Protection Act (1999), you are advised that, should any inconsistencies be found, the legal documents, printed in the Canada Gazette, will prevail.