Vol. 151, No. 24 — June 17, 2017
Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999
- Statutory authority
- Canadian Environmental Protection Act, 1999
- Sponsoring departments
- Department of the Environment
- Department of Health
(This statement is not part of the Order.)
The Government of Canada (the Government) has conducted a screening assessment (see footnote 1) on five Methylenediphenyl Diisocyanate (MDI) substances, hereafter referred to as “the five MDIs” and has determined that the five MDIs meet the human health criterion for toxicity as defined in paragraph 64(c) of the Canadian Environmental Protection Act, 1999 (CEPA). Therefore, the Government is proposing to add the five MDIs to the List of Toxic Substances in Schedule 1 of CEPA. The substances are as follows:
- Benzene, 1,1′-methylenebis[4-isocyanato- (Chemical Abstracts Service Registry Number [CAS RN] 101-68-8), known as “4,4′-MDI”;
- Benzene, 1,1′-methylenebis[2-isocyanato- (CAS RN 2536-05-2), known as “2,2′-MDI”;
- Benzene, 1-isocyanato-2-[(4-isocyanatophenyl)methyl]- (CAS RN 5873-54-1), known as “2,4′-MDI”;
- Benzene, 1,1′-methylenebis[isocyanato- (CAS RN 26447-40-5), known as “mixed MDI”; and
- Isocyanic acid, polymethylenepolyphenylene ester (CAS RN 9016-87-9), known as “pMDI.”
The Chemicals Management Plan (CMP) was launched by the Government to assess and manage chemical substances that may be harmful to human health or the environment. (see footnote 2) One of the initiatives under the CMP is the Substance Groupings Initiative, in which the Minister of Health and the Minister of the Environment (the ministers) are assessing and, where appropriate, managing the potential health and ecological risks associated with approximately 500 substances. To facilitate the screening assessment process, these substances were grouped into nine groups based on similar chemical properties and other key similarities. (see footnote 3)
One of these groupings is the Methylenediphenyl Diisocyanate and Diamine (MDI/MDA) Substance Grouping. This group of substances included the five MDIs, subject to the proposed Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999 (the proposed Order), which were identified as priorities for action, as they either met the categorization criteria under section 73 of CEPA (see footnote 4) and/or were considered as priorities for assessment based on human health concerns.
Substances description and uses in Canada
The five MDIs can be used to produce a wide variety of materials for commercial and consumer use, such as oriented strand board (OSB) or engineered wood products, and polyurethane products that include elastomer applications, foam cushion and do-it-yourself (DIY) products used for construction, such as adhesives, insulation foam, and sealants.
Based on information collected in response to a mandatory survey issued under the authority of CEPA, industry submitted data on the activities related to the five MDIs to the Government. In Canada, the five MDIs were reported to be used in the manufacturing of polyurethane flexible and rigid foam, elastomers, coatings, adhesives and sealants, which are then used in industries such as furniture manufacturing, construction, and the automotive sector as well as in do-it-yourself (DIY) products. Other manufactured items such as OSB, particle board and other wood products are produced in Canada for further use in construction. There were no reports of the five MDIs being manufactured above the reporting threshold of 100 kg per year. However, the combined quantity of the substances imported into Canada in 2011 was in the range of 10 million to 100 million kg.
The five MDIs are primarily released to air through industrial use in the manufacture of polyurethane and OSB or engineered wood products. However, inhalation exposure to the five MDIs can also result from the use of DIY products in construction projects.
Existing Canadian and international risk management instruments
Existing risk management actions targeting MDIs in Canada are mostly related to the industrial use of the substances, which includes their presence in ambient air and tracking releases to the environment. For example, at the federal level, 4,4′-MDI and polymeric MDI are substances reportable to the National Pollutant Release Inventory. Further, the Controlled Products Regulations established under the Hazardous Products Act require that 4,4′-MDI be disclosed on the Safety Data Sheet (document that contains information on the potential hazards and how to work safely with the chemical product) that must accompany workplace chemicals when it is present at a concentration of 0.1%.
Internationally, a number of assessment and management actions are being undertaken in other jurisdictions. In the United States, MDIs are part of the Toxic Substances Control Act Action Plan and options are being considered to address the potential health risks. MDIs are also subject to California’s Safer Consumer Products Regulations and performance standards under the federal Clean Air Act. MDIs are substances reportable to Australia’s National Pollutant Inventory. MDIs are also identified as substances that pose a health risk in several countries in the European Union. (see footnote 5)
Screening assessment summary
Using available information, which includes the results of a mandatory survey issued under the authority of CEPA, submission of additional data by industry and an analysis of existing scientific data, the Government conducted a screening assessment to determine if the five MDIs would meet one or more of the criteria for toxicity as defined in section 64 of CEPA. Specifically, this involves determining whether the five MDIs are entering or may enter the environment in a quantity or concentration or under conditions that
- (a) have or may have an immediate or long-term harmful effect on the environment or its biological diversity;
- (b) constitute or may constitute a danger to the environment on which life depends; or
- (c) constitute or may constitute a danger in Canada to human life or health.
Human health assessment
Based on the collective information and classifications by other international regulatory agencies, the risk to human health associated with exposure to the five MDIs include cancer risk, respiratory problems, and dermal sensitization. The European Commission has classified MDIs as Category 1 respiratory sensitizers and Category 1 skin sensitizers. (see footnote 6) Animal laboratory studies, human case reports and epidemiological studies all indicate that the five MDIs are associated with sensitization of the respiratory tract. (see footnote 7) The potential risk to human health from exposure to the five MDIs was evaluated by comparing the concentration levels at which the five MDIs become a hazard to human health (including carcinogenicity) to the estimated current level of exposure of the general population of Canada to the five MDIs.
A potential source of exposure to the five MDIs is inhalation of ambient air for the general population residing in the vicinity of industrial sites (e.g. wood product manufacturing plant using MDIs). Another potential source of exposure to the five MDIs for the general population of Canada is expected to be the use of DIY type of products (e.g. low-pressure two-component spray polyurethane foam, one-component foam sealant, and polyurethane sealant). Exposure to these products would be short-term and may occur through inhalation and dermal routes.
It was estimated that the application of low-pressure two-component spray polyurethane foam products by homeowners for insulation and sealing may result in levels of inhalation that could pose a danger to human health. For all other uses, including one component spray foams and adhesives, it was determined that exposure levels are low enough that they do not pose any human health concern. (see footnote 8)
Based on the estimated levels of exposure to the five MDIs from certain DIY products, and the resulting risks to human health, the screening assessment concluded that the five MDIs meet the criterion under paragraph 64(c) of CEPA.
The five MDIs belong to a highly reactive class of chemicals. They are known to hydrolyze quickly and, as a result, have only a brief existence in environmental media such as water or soil, where a degree of moisture is typically present. For this reason, it is considered that the five MDIs tend to not be present in appreciable concentrations in the environment for prolonged periods of time; they are therefore not available for uptake by non-human organisms and are very unlikely to biomagnify in aquatic or terrestrial food webs. Available empirical evidence in fish from exposure to the five MDIs over 28 days suggests that the five MDIs do not bioaccumulate in fish either. In addition, ecotoxicity studies were performed for a soil invertebrate (the earthworm) and two plant species. Very low toxicity was observed in all studies based on a short-term exposure time of two weeks to the five MDIs.
Based on the empirical ecotoxicity data and levels of exposure in various environmental compartments (i.e. air, water, soil and sediment), it was determined that at current concentration levels, the five MDIs are unlikely to cause harm to aquatic, benthic or soil-dwelling organisms or terrestrial wildlife. Considering all available lines of evidence presented in the screening assessment, it is concluded that the five MDIs do not meet the environmental criteria under paragraph 64(a) or (b) of CEPA.
Assessment publication and conclusions
In August 2014, a draft screening assessment for the MDI/MDA Substance Grouping, which included the five MDIs, was published in the Canada Gazette, Part I, for a 60-day public comment period.
On June 10, 2017, the final screening assessment for the MDI/MDA Substance Grouping, which included the five MDIs, was published on the Government’s Chemical Substances website. Based on the results of the final assessment, it has been concluded that the five MDIs meet the human health criterion for a toxic substance, as set out under paragraph 64(c) of CEPA. The Government has therefore recommended the addition of the five MDIs to Schedule 1 of CEPA.
The objective of the proposed Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999 is to enable the Government to propose risk management activities under CEPA to manage potential risks to human health associated with the five MDIs, should such activities be deemed necessary.
The proposed Order would add the five MDIs to Schedule 1 of CEPA.
The “One-for-One” Rule does not apply, as the proposed Order would not impose any administrative burden on business.
Small business lens
The small business lens does not apply, as the proposed Order would not impose any compliance or administrative costs to small business.
On August 16, 2014, the Government published a summary of the draft screening assessment for the MDI/MDA Substance Grouping, which included the five MDIs, in the Canada Gazette, Part I, for a 60-day public comment period. A proposed risk management scope document outlining the preliminary options being examined for the management of these substances was also released on the same date. During the 60-day public comment period, a total of 10 submissions were received from 4 industry stakeholders, 4 industry associations, 1 non-governmental organization and 1 research institute on the scientific assessment for the MDI/MDA Substance Grouping. All comments were considered in developing the final screening assessment.
Prior to these publications, the Department of the Environment and the Department of Health informed the governments of the provinces and territories, through the CEPA National Advisory Committee (NAC), of the release of this document and of the related public comment period. No comments were received from CEPA NAC. (see footnote 9)
A table summarizing the complete comments received and the Government’s responses is available on the Chemical Substances website at www.ec.gc.ca/ese-ees/default.asp?lang=En&n=8BC9294C-1. The key comments and responses are summarized below.
Overview of public comments and responses
Comments received touched on a variety of topics, including methodology, but focused primarily on additional information and data in the assessment.
Methodology: Stakeholders pointed out certain aspects of the risk assessment that they felt could be inaccurate, recommended modifications to some values and recommended certain additions or clarifications to improve the assessment. Government officials responded to the requests by either providing a justification for the information presented in the risk assessment or by describing the changes to the final risk assessment made as a result of the information received from stakeholders.
Additional information and data: Stakeholders submitted additional data on MDI emissions during application and concentration in the air and requested that this data, as well as other recently submitted studies on this topic, be considered in the final screening assessment. In addition, stakeholders commented that the screening assessment should recognize that spray polyurethane foam products containing MDIs can be formulated differently depending on the purpose of the application, suggesting that low-pressure two-component products could result in a lower exposure potential to those using the products. Government officials responded that all stakeholder data and information that was submitted was considered in the final screening assessment and confirmed that only measurements of MDI concentrations during the application of low-pressure two-component products were used in the final screening assessment to estimate homeowner exposure and risk.
There is evidence that the five MDIs pose a number of human health risks, including skin irritation, respiratory problems, and cancer. A number of DIY products contain the five MDIs. Users of these products can be exposed to the five MDIs at levels that could pose a risk to their health. Therefore, it is concluded that the five MDIs meet the criterion under paragraph 64(c) of CEPA, as they are entering the environment in a quantity or concentration or under conditions that may constitute a danger in Canada to human health.
One of the following measures must be proposed after a screening assessment is conducted under CEPA:
- taking no further action under CEPA with respect to the substance;
- adding the substance to the Priority Substances List for further assessment; or
- recommending that the substance be added to the List of Toxic Substances in Schedule 1 of CEPA, and where applicable, recommending the implementation of virtual elimination.
Considering all available lines of evidence presented in the final screening assessment, it is concluded that the five MDIs pose a risk to human health. The Government has determined that choosing option 1 or 2 is not appropriate to manage the potential human health risks associated with the five MDIs. Therefore, option 3, which recommends that the five MDIs be added to the List of Toxic Substances in Schedule 1 of CEPA, is the option proposed by the Government. (see footnote 10)
The proposed addition of the five MDIs to Schedule 1 of CEPA would not result in any incremental impacts (benefits or costs) on the public or industry, since the proposed Order would not impose any compliance requirement on stakeholders. Accordingly, there would be no administrative burden imposed on small businesses or businesses in general. Rather, the proposed Order is an enabling instrument that allows the Government to propose risk management activities under CEPA, should they be deemed necessary.
If further risk management measures are deemed necessary for the five MDIs, the Government will consider the costs and benefits and consult with the public and other stakeholders during the development of any risk management measure to address potential human health concerns associated with uses of the five MDIs in Canada.
In accordance with the Cabinet Directive on the Environmental Assessment of Policy, Plan and Program Proposals, a strategic environmental assessment was completed under the CMP. (see footnote 11)
Implementation, enforcement and service standards
The proposed Order would add the five MDIs to Schedule 1 of CEPA, thereby enabling the Government to propose regulations or instruments respecting preventive or control actions, should these regulations or instruments be deemed necessary. As developing an implementation plan or an enforcement strategy, or establishing service standards are only considered necessary when there is a specific risk management proposal, these measures are not necessary for this proposed Order.
Program Development and Engagement Division
Department of the Environment
Substances Management Information Line:
1-800-567-1999 (toll-free in Canada)
819-938-3232 (outside of Canada)
Risk Management Bureau
Department of Health
Notice is given, pursuant to subsection 332(1) (see footnote a) of the Canadian Environmental Protection Act, 1999 (see footnote b), that the Governor in Council, on the recommendation of the Minister of the Environment and the Minister of Health, pursuant to subsection 90(1) of that Act, proposes to make the annexed Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999.
Any person may, within 60 days after the date of publication of this notice, file with the Minister of the Environment comments with respect to the proposed Order or a notice of objection requesting that a board of review be established under section 333 of that Act and stating the reasons for the objection. All comments and notices must cite the Canada Gazette, Part I, and the date of publication of this notice, and be sent by mail to the Executive Director, Program Development and Engagement Division, Department of the Environment, Gatineau, Quebec K1A 0H3, by fax to 819-938-5212 or by email to firstname.lastname@example.org.
A person who provides information to the Minister of the Environment may submit with the information a request for confidentiality under section 313 of that Act.
Ottawa, June 8, 2017
Assistant Clerk of the Privy Council
Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999
1 Schedule 1 to the Canadian Environmental Protection Act, 1999 (see footnote 12) is amended by adding the following:
Benzene, 1,1′-methylenebis[4-isocyanato-, which has the molecular formula C15H10N2O2
Benzene, 1,1′-methylenebis[2-isocyanato-, which has the molecular formula C15H10N2O2
Benzene, 1-isocyanato-2-[(4-isocyanatophenyl)methyl]-, which has the molecular formula C15H10N2O2
Benzene, 1,1′-methylenebis[isocyanato-, which has the molecular formula C15H10N2O2
Isocyanic acid, polymethylenepolyphenylene ester, which has the molecular formula C15H10N2O2•[C8H5NO]n in which 0≤n≤4
Coming into Force
2 This Order comes into force on the day on which it is registered.
- Footnote 1
For more information on the scientific assessment for the five MDIs, please see the screening assessment at http://ec.gc.ca/ese-ees/default.asp?lang=En&n=14B737B2-1.
- Footnote 2
For more information on the CMP, please visit http://www.chemicalsubstanceschimiques.gc.ca/plan/index-eng.php.
- Footnote 3
For more information on the Substance Grouping Initiative, please visit http://www.chemicalsubstanceschimiques.gc.ca/group/index-eng.php.
- Footnote 4
73(1) The ministers shall, within seven years from the giving of Royal Assent to this Act, categorize the substances that are on the Domestic Substances List by virtue of section 66, for the purpose of identifying the substances on the List that, in their opinion and on the basis of available information, (a) may present, to individuals in Canada, the greatest potential for exposure; or (b) are persistent or bioaccumulative in accordance with the regulations, and inherently toxic to human beings or to non-human organisms, as determined by laboratory or other studies.
- Footnote 5
For more information on international risk management actions, please see the risk management approach document for MDIs on the Chemical Substances website.
- Footnote 6
According to the official journal of the European Union, “Substances shall be classified as respiratory sensitizers (Category 1) in accordance with the following criteria: (a) if there is evidence in humans that the substance can lead to specific respiratory hypersensitivity; and/or (b) if there are positive results from an appropriate animal test.” Moreover, “Substances shall be classified as skin sensitizers (Category 1) in accordance with the following criteria: (i) if there is evidence in humans that the substance can lead to sensitisation by skin contact in a substantial number of persons, or (ii) if there are positive results from an appropriate animal test.”
- Footnote 7
For more information on these studies, please see the screening assessment report for MDI/MDA on the Chemical Substances website.
- Footnote 8
For more information on the health assessment for the five MDIs, please see the screening assessment report for MDI/MDA on the Chemical Substances website.
- Footnote 9
Section 6 of CEPA provides that the CEPA NAC be the main intergovernmental forum for the purpose of enabling national action and avoiding duplication in regulatory activity among governments within Canada. This committee has a representative from the Department of the Environment and the Department of Health, a representative of each of the provinces and territories as well as up to six representatives of Aboriginal governments.
- Footnote 10
The five MDIs did not meet the virtual elimination criteria under CEPA. For more information, please see https://www.ec.gc.ca/lcpe-cepa/26A03BFA-C67E-4322-AFCA-2C40015E741C/lcpe-cepa_201310125_loi-bill.pdf.
- Footnote 11
For more information on the strategic environmental assessment of the CMP, please visit http://www.chemicalsubstanceschimiques.gc.ca/plan/sea-ees-eng.php.
- Footnote a
S.C. 2004, c. 15, s. 31
- Footnote b
S.C. 1999, c. 33
- Footnote 12
S.C. 1999, c. 33