Vol. 145, No. 4 — February 16, 2011

Registration

SOR/2011-25 February 4, 2011

CANADIAN ENVIRONMENTAL PROTECTION ACT, 1999

ARCHIVED — Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999

P.C. 2011-61 February 3, 2011

Whereas, pursuant to subsection 332(1) (see footnote a) of the Canadian Environmental Protection Act, 1999 (see footnote b), the Minister of the Environment published in the Canada Gazette, Part I, on May 16, 2009, a copy of the proposed Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999, and persons were given an opportunity to file comments with respect to the proposed Order or to file a notice of objection requesting that a board of review be established and stating the reasons for the objection;

And whereas, pursuant to subsection 90(1) of that Act, the Governor in Council is satisfied that the substances set out in the proposed Order are toxic substances;

Therefore, His Excellency the Governor General in Council, on the recommendation of the Minister of the Environment and the Minister of Health, pursuant to subsection 90(1) of the Canadian Environmental Protection Act, 1999 (see footnote c), hereby makes the annexed Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999.

ORDER ADDING TOXIC SUBSTANCES TO SCHEDULE 1 TO THE CANADIAN ENVIRONMENTAL PROTECTION ACT, 1999

AMENDMENT

1. Schedule 1 to the Canadian Environmental Protection Act, 1999 (see footnote 1) is amended by adding the following in numerical order:

97. Thiourea, which has the molecular formula CH₄N₂S

98. 1,3-Butadiene, 2-methyl-, which has the molecular formula C₅H₈

99. Oxirane, (chloromethyl)-, which has the molecular formula C₃H₅ClO

100. Colour Index Pigment Yellow 34

101. Colour Index Pigment Red 104

102. Cyclotetrasiloxane, octamethyl-, which has the molecular formula C₈H₂₄O₄Si₄

103. Phenol, 2,4,6-tris(1,1-dimethylethyl)-, which has the molecular formula C₁₈H₃₀O

COMING INTO FORCE

2. This Order comes into force on the day on which it is registered.

REGULATORY IMPACT
ANALYSIS STATEMENT

(This statement is not part of the Order.)

Issue and objectives

Canadians depend on chemical substances that are used in the manufacturing of hundreds of goods, from medicines to computers, fabrics and fuels. Unfortunately, some chemical substances can negatively affect human health and the environment when released to the environment in a certain quantity or concentration or under certain conditions. Scientific assessments of the impact of human and environmental exposure have determined that a number of these substances constitute or may constitute a danger to human health and/or the environment as per the criteria set out under section 64 of the Canadian Environmental Protection Act, 1999 (CEPA 1999, also referred to as “the Act”).

The Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999 (hereinafter referred to as the Order), made pursuant to subsection 90(1) of CEPA 1999, adds the following substances to the List of Toxic Substances in Schedule 1 of CEPA 1999:

• Thiourea ((Chemical Abstracts Service Registry Number [CAS RN] 62-56-6),
• 1,3-Butadiene, 2-methyl- (CAS No. 78-79-5), hereafter referred to as “isoprene,”
• Oxirane, (chloromethyl)- (CAS No. 106-89-8), hereafter referred to as “epichlorohydrin,”
• Colour Index Pigment Red 104 (CAS No. 12656-85-8), hereafter referred to as “C.I. Pigment Red 104,”
• Colour Index Pigment Yellow 34 (CAS No. 1344-37-2), hereafter referred to as “C.I. Pigment Yellow 34,”
• Cyclotetrasiloxane, octamethyl- (CAS No. 556-67-2), hereafter referred to as “D4,” and
• Phenol, 2,4,6-tris(1,1-dimethylethyl)- (CAS No. 732-26-3), hereafter referred to as “2,4,6-tri-tert-butylphenol.”

This addition enables the Ministers to develop proposed regulations or instruments to manage human health and environmental risk posed by these substances under CEPA 1999. The Ministers may also choose to develop non-regulatory instruments to manage these risks.

Description and rationale

Background

Approximately 23 000 substances (often referred to as “existing” substances) were in use in Canada between January 1, 1984, and December 31, 1986. These substances are found on the Domestic Substances List (DSL), but many of them have never been assessed as to whether they meet any of the criteria set out in section 64 of CEPA 1999. Section 73 of the Act required that substances on the DSL be categorized to determine which of them pose the greatest potential for exposure to the general population. Categorization also determines which of these substances are persistent or bioaccumulative in accordance with the Regulations and inherently toxic to human beings or to non-human organisms. Pursuant to section 74 of the Act, substances that were flagged during the categorization process must undergo an assessment to determine whether they meet any of the criteria set out in section 64. Assessments may also be conducted under section 68 of the Act for substances identified as high priorities for action, but that do not meet the categorization criteria set out under section 73 of the Act.

The Minister of the Environment and the Minister of Health (the Ministers) completed the categorization exercise in September 2006. Of the approximately 23 000 substances on the DSL, about 4 300 were identified as needing further attention, and approximately 200 of these were identified as high priorities for action.

As a result of categorization, the Chemicals Management Plan was launched on December 8, 2006, with the objective of enhancing the protection against hazardous chemicals.

A key element of the Plan is the collection of information on the properties and uses of the approximately 200 substances identified as high priorities for action. This includes substances

• that were found to meet the categorization criteria for persistence, bioaccumulation potential and inherent toxicity to non-human organisms, and that are known to be in commerce, or of commercial interest, in Canada; these substances are considered to be high priorities for assessment of ecological risk; and/or
• that were found either to meet the categorization criteria for greatest potential for exposure of Canadians or to present an intermediate potential for exposure, and were identified as posing a high hazard to human health based on available evidence on carcinogenicity, mutagenicity, developmental toxicity or reproductive toxicity; these substances are considered to be high priorities for assessment of risk to human health.

This information is being used to make decisions regarding the best approaches to be taken in order to protect Canadians and their environment from the risks these substances might pose. This information-gathering initiative is known as the “Challenge.”

To facilitate the process, Environment Canada and Health Canada have organized the approximately 200 substances into 12 batches of approximately 15 substances. A batch is released every three months, and stakeholders are required to report information such as quantities imported, manufactured or used in Canada via a mandatory survey issued under section 71 of CEPA 1999. Affected parties are required to submit this information to better inform decision making, including determining whether a substance meets one or more of the criteria set out in section 64 of CEPA 1999 — that is to say, whether the substance is entering or may enter 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;
• constitute or may constitute a danger to the environment on which life depends; or
• constitute or may constitute a danger in Canada to human life or health.

Based on the information received and other available information, screening assessments are conducted in order to assess whether substances meet one or more of the criteria of section 64. The screening assessments are peer-reviewed and additional advice is also sought, as appropriate, through the Challenge Advisory Panel. The Panel, made up of experts from various fields such as chemical policy, chemical production, economics and environmental health, was formed to provide advice to Government on the application of precaution and weight of evidence to screening assessments in the Challenge. These screening assessments are then published on the Chemical Substances Web site at www. chemicalsubstances.gc.ca along with notices that are published in the Canada Gazette, Part I, that signal the Ministers’ intent with regard to further risk management.

The Minister of the Environment is required under section 91 of CEPA 1999 to publish in the Canada Gazette a proposed regulation or instrument establishing preventive or control actions within two years of publishing a statement under paragraph 77(6)(b) of CEPA 1999 indicating that the measure the Ministers propose to take, as confirmed or amended, is a recommendation that the substance be added to the List of Toxic Substances in Schedule 1 of CEPA 1999. Section 92 then requires that the regulation or instrument be finalized and published within 18 months following publication in the Canada Gazette, Part I.

The addition of these substances on Schedule 1 of CEPA 1999 allows the Ministers to develop risk management instruments in order to meet these obligations. The Act enables the development of risk management instruments (such as regulations, guidelines or codes of practice) to protect the environment and human health. These instruments can be developed for any aspect of the substance’s life cycle, from the research and development stage through manufacture, use, storage, transport and ultimate disposal or recycling. Proposed Risk Management Approach documents, which provide an indication of where the Government will focus its risk management activities, have been prepared for Batch 2 substances and are available on the Chemical Substances Web site listed above.

The final screening assessments for the second batch of the Challenge comprising 17 substances were published on the Chemical Substances Web site (www.chemicalsubstanceschimiques.gc.ca/ challenge-defi/batch-lot-2/index-eng.php), and the statements recommending the addition to Schedule 1 were published in the Canada Gazette, Part I. The final assessment for bisphenol A, one of these Batch 2 substances, was published on October 17, 2008. The final assessments for the remaining 16 substances were published on January 31, 2009.

It was concluded that eight of these remaining 16 substances met one or more of the criteria set out in section 64 of CEPA 1999. Seven of these substances are included in this Order. Of these seven substances, five substances constitute or may constitute a danger in Canada to human life or health and two substances have or may have an immediate or long-term harmful effect on the environment or its biological diversity. The remaining substance, cyclopentasiloxane, decamethyl- (CAS RN. 541-02-6) also known as “D5,” a substance which was initially proposed for addition to Schedule 1 of CEPA 1999, is not included in this Order. A board of review has been established to inquire into the nature and the extent of the danger posed by D5 (see www.siloxaned5.ca/).

A summary of the assessments and conclusions and an overview of the public comments received during the public comment period on the draft assessment report and on the risk management scope documents for the substances are available from the Chemical Substances Web site at this location: www.chemicalsubstanceschimiques.gc.ca/challenge-defi/batch-lot-2/ index-eng.php.

Substances descriptions, assessment summaries and conclusions for Batch 2 substances listed in Schedule 1

1. Human health priority substances

Thiourea is used in copper refining, in the manufacture of printed circuit boards, in various types of copy paper, in silver polish/metal cleaners, and in black and white photographic chemicals. Thiourea was not reported as being manufactured in Canada in quantities above the 100 kg reporting threshold. (see footnote 2) Imports of the substance into Canada in 2006 were reported in the range of 10 000 kg to 100 000 kg. Thiourea was assessed as a high priority for human health risk. The assessment has determined that thiourea may cause reproductive or developmental effects and cancer in laboratory animals. These results are based principally on the weight-of-evidence-based assessments or classifications of several international or national agencies (International Agency for Research on Cancer [IARC], National Toxicology Program [U.S.], Environment Canada, and International Program on Chemical Safety [IPCS]).

Isoprene is used mainly in the manufacture of rubbers and plastics, such as medical equipment, tires, paints, inner tubes and some rubber adhesives and glues. It is both manufactured in and imported into Canada. The total quantity of isoprene reported as being manufactured in Canada in 2006 exceeded 10 000 000 kg and the total quantity imported ranged from 1 000 000 to 10 000 000 kg. Isoprene was assessed as a high priority for human health risk. The assessment has determined that isoprene can cause reproductive or developmental effects and cancer in laboratory animals. These results are based principally on the weight-of-evidence-based assessments or classifications of several international or national agencies (International Agency for Research on Cancer [IARC], National Toxicology Program [U.S.], and the European Commission).

Epichlorohydrin is used to make other chemical products, such as epoxy resins, which are used in paints and protective coatings and adhesives. It is also sometimes used in the production of substances designed to help remove impurities in drinking water and wastewater, in paper products and in the powder coating inside latex gloves. Epichlorohydrin was reported as not being manufactured or imported into Canada above the 100 kg reporting threshold. Epichlorohydrin was assessed as a high priority for human health risk. The assessment has determined that epichlorohydrin may cause cancer in laboratory animals. These results are based principally on the weight-of-evidence-based assessments or classifications of several international or national agencies (United States Environmental Protection Agency [EPA], International Agency for Research on Cancer [IARC], National Toxicology Program [U.S.], and European Chemical Substances Information System [ESIS]).

C.I. Pigment Yellow 34 and C.I. Pigment Red 104 are used as plastic formulants for commercial applications and export; commercial, non-consumer paints and coatings; and a very limited number of commercial printing inks or coatings used for plastics and certain outdoor applications such as commercial identification decals. Each pigment has been reported to be manufactured and imported in Canada in quantities ranging between 1 000 000 kg and 10 000 000 kg. After exports, quantities remaining for use in Canada range between 1 000 000 kg and 10 000 000 kg for C.I. Pigment Yellow 34 and between 100 000 kg and 1 000 000 kg for C.I. Pigment Red 104. The scientific assessments have determined that the effects of these two pigments, which are human health priority substances, may include cancer and reproductive or developmental effects in laboratory animals. This conclusion is based principally on the weight-of-evidence-based classification of C.I. Pigment Yellow 34 and C.I. Pigment Red 104 by the European Commission as a Category 3 carcinogen (possible carcinogenic effects on humans) and the assessments of hexavalent chromium and inorganic lead compounds, which are found in these pigments, by several national and international agencies (U.S. Environmental Protection Agency [EPA], International Agency for Research on Cancer [IARC], Environment Canada/Health Canada, and National Toxicology Program [U.S.]).

Final assessment conclusions on the health priority substances

On the basis of the carcinogenicity for which there is a possibility of harm at any level of exposure as well as other non cancer effects, it is concluded that thiourea, epichlorohydrin, isoprene, C.I. Pigment Yellow 34 and C.I. Pigment Red 104 are 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 as set out in paragraph 64(c) of CEPA 1999. These substances are thus recommended for addition to Schedule 1 of CEPA 1999.

2. Ecological priority substances

D4 is a man-made substance used primarily in the manufacture of silicone polymers. Other known uses include in lubricants, cleaning products, sealants, adhesives, waxes, polishes and coatings and in personal care products such as hair/skin care products and antiperspirants/deodorants, as well as pharmaceuticals. D4 is part of the chemical class called siloxanes, which includes a number of substances. Two other siloxanes, D5 and D6, were assessed under the Challenge Batch 2 initiative. D4 was not reported as being manufactured in Canada in 2006 in quantities above the 100 kg reporting threshold, but it was determined that between 1 000 000 and 10 000 000 kg of D4 were imported into Canada in 2006. The principal sources of release of D4 to the environment are through the use of personal care products and industrial processes. Experimental results found in the scientific literature demonstrate that D4 has the potential to cause adverse effects to sensitive aquatic organisms, such as water fleas and early life-stage fish. Long-term environmental exposure to D4 may cause adverse effects to aquatic organisms in certain Canadian environments. D4 has significant bioaccumulative potential in organisms, but it was not found at this time to meet the persistence and bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations. (see footnote 3) Quantities estimated to be released to the environment are above levels expected to cause harm to organisms. Based on this evidence, it is concluded that D4 has the potential to cause ecological harm.

D4 is being assessed under various international programs. The European Union, under the REACH (Registration, Evaluation, Authorisation and Restriction of Chemical substances) legislation, is continuing the assessment of D4 initiated by the United Kingdom. Assessment is being continued, following the recent receipt of data on D4 generated in response to EU regulations. The United States government and the chemicals industry are co-sponsoring an investigation on D4 under the High Production Volume Chemicals Program of the Organisation for Economic Co-operation and Development (OECD). In addition, the United States is currently developing an Existing Chemicals Action Plan for siloxanes.

2,4,6-Tri-tert-butylphenol is a man-made substance used in Canada as a fuel additive. As per the most recent section 71 data-gathering survey, this substance was not reported as being manufactured in Canada in 2006 in quantities meeting the 100 kg reporting threshold, but was imported in the range of 1 000 to 10 000 kg and used in the range of 1 000 to 10 000 kg. There is evidence that the substance is highly persistent, and has the potential to bioaccumulate in organisms. The substance 2,4,6-tri-tert-butylphenol is destroyed through the combustion of fuel and oil, but accidental releases into the Canadian environment could be harmful as the substance has the potential to cause adverse effects to organisms.

2,4,6-Tri-tert-butylphenol has been identified as a High Production Volume (HPV) chemical under the United States Environmental Protection Agency’s HPV Challenge Program. This program challenged companies to make health and environmental effects data publicly available for chemicals produced in high quantities. It is also included on the OECD list of HPV chemicals. 2,4,6-tri-tert-butylphenol is part of the Oslo-Paris (OSPAR) Commission’s list of chemicals for priority action. Importation, manufacture and use of the substance has been banned in Japan.

Final assessment conclusions on the ecological priority substances

Based on the information available, it is concluded that D4 and 2,4,6-tri-tert-butylphenol are entering or may enter 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 as defined under section 64 of CEPA 1999. These substances are thus recommended for addition to Schedule 1 of CEPA 1999.

In addition, the presence of 2,4,6-tri-tert-butylphenol in the environment results primarily from human activity, and the available data regarding persistence and bioaccumulation indicate that the substance meets the criteria set out in the Persistence and Bioaccumulation Regulations, made under CEPA 1999. The substance thus meets the criteria requiring the implementation of virtual elimination of releases to the environment as defined under subsection 77(4) of CEPA 1999.

The final screening assessment reports, the proposed risk management approach documents and the complete responses to comments received on both ecological and health priority substances were published on January 31, 2009, and may be obtained from the Chemical Substances website at www. chemicalsubstanceschimiques.gc.ca/challenge-defi/batch-lot-2/ index-eng.php or from the Program Development and Engagement Division, Gatineau, Quebec K1A 0H3, 819-953-7155 (fax), Substances@ec.gc.ca (email).

Alternatives

The following measures can be taken after a screening assessment is conducted under CEPA 1999:

• adding the substance to the Priority Substances List for further assessment (when additional information is required to determine whether or not a substance meets the criteria in section 64);
• taking no further action in respect of the substance; or
• recommending that the substance be added to the List of Toxic Substances in Schedule 1 and, where applicable, recommending the implementation of virtual elimination.

It has been concluded in the final screening assessments that thiourea, isoprene, epichlorohydrin, C.I. Pigment Yellow 34, and C.I. Pigment Red 104 are entering, or may enter, the environment in a quantity or concentration or under conditions that constitute or may constitute a danger in Canada to human life or health as defined under section 64(c) of CEPA 1999. It has also been concluded that D4 and 2,4,6-tri-tert-butylphenol are entering, or may enter, 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 as set out in section 64(a) of CEPA 1999.

Adding these seven substances to Schedule 1, which will enable the development of proposed regulations or other risk management instruments, is therefore the best option.

In addition, the presence of 2,4,6-tri-tert-butylphenol in the environment results primarily from human activity. The substance is not a naturally occurring radionuclide or inorganic substance and is persistent and bioaccumulative, as set out in the Persistence and Bioaccumulation Regulations. Consequently, the Ministers will follow the process specified in CEPA 1999 for substances that meet the criteria for virtual elimination of releases to the environment.

Benefits and costs

Adding these substances to Schedule 1 enables the Ministers to develop regulations to manage human health and environmental risks posed by these substances. The Ministers may also choose to develop non-regulatory instruments to manage these risks. The Ministers will undertake an assessment of the potential impacts, including an economic analysis, and consult with the public and other stakeholders during the development of these risk management proposals.

Consultation

On May 17, 2008, the Ministers published for a 60-day public comment period in the Canada Gazette, Part I, a summary of the screening assessments for 16 of the substances of Batch 2. Risk management scope documents outlining the preliminary options being examined for the management of these substances were also released on the same date for substances proposed to be considered as meeting one or more of the criteria set out under section 64 of the Act. Prior to this publication, the CEPA National Advisory Committee (CEPA NAC) was informed of the release of the screening assessment reports, the risk management scope documents, and the public comment period mentioned above. No comments were received from CEPA NAC. Additionally, the Challenge Advisory Panel provided advice on the approach taken by Environment Canada and Health Canada (the departments) related to siloxanes.

During the 60-day public comment period, a total of 57 submissions were received from 37 industry stakeholders, 13 industry associations, 5 non-governmental organizations, one research center and one foreign government agency on the scientific assessment and risk management scope documents. All comments were considered in developing the final screening assessments. Comments received on the risk management scope documents regarding these substances were also considered when developing the proposed risk management approach documents. The latter were also subject to a 60-day public comment period.

Below is a summary of some key comments specific to the assessment conclusions for toxicity and the responses of Health Canada and Environment Canada (the departments) to them. In cases where comments have been made concerning whether or not a substance meets one or more of the criteria of section 64 of the Act that indicate a lack of information or uncertainty, the Government errs on the side of precaution to protect the health of Canadians and their environment. The complete responses to public comments are available via the Government of Canada’s Chemical Substances Web site, address, fax number or email mentioned above.

Summary of key comments on some human health priority substances

Isoprene

Chemical manufacturers commented that it is inappropriate to designate isoprene as meeting the criteria under section 64 of CEPA based on its natural sources.

Response: This comment was considered, and it is noted in the assessment that the contribution of natural versus man-made sources of isoprene to general exposure of the Canadian population is not known. A conclusion of CEPA toxic means that the government can now take regulatory actions to reduce man-made sources.

Epichlorohydrin

Chemical manufacturers commented that the substance should not be concluded as meeting the criteria under section 64 of CEPA or placed on Schedule 1 of CEPA 1999, because exposure varies from low to negligible.

Response: Due to uncertainties associated with the exposure dataset for epichlorohydrin, caused by information gaps, the screening assessment used conservative assumptions, in accordance with the application of a precautionary approach as required by CEPA 1999. Using these conservative estimates, Canadians’ exposure is expected to vary from low to negligible. However, the critical effect for epichlorohydrin is considered not to have a threshold of exposure, and in such cases, it is assumed that there is a probability of harm to human health at any level of exposure.

Summary of comments on ecological priority substances

D4

Both chemical manufacturers and chemical industry associations indicated concern that there was uncertainty in the findings presented in the draft assessment report regarding whether or not D4 meets both the persistence and bioaccumulation criteria, and expressed disagreement with these conclusions. They indicated that further testing and field studies were underway and would be available after the date scheduled for publication of the final assessment. They further suggested that screening assessments should be based on all available scientific data. The Minister of the Environment was urged to consider deferring a final decision on this substance until these new data are available.

Response: The final assessment was published at the scheduled time, and recognizes the uncertainties associated with the persistence and bioaccumulation potentials of D4. Based on consideration of additional information received during the public comment period on the draft screening assessment report, Environment Canada did not conclude at this time that D4 meets the bioaccumulation criteria as defined in the Persistence and Bioaccumulation Regulations, made under CEPA 1999. It was concluded, however, that the persistence criteria defined in the Regulations are met. Environment Canada recognizes that ongoing research is being conducted to increase the scientific understanding of the bioaccumulation potential of D4. Irrespective of the conclusions on persistence and bioaccumulation, it was concluded that D4 has the potential to cause ecological harm.

2,4,6-Tri-tert-butylphenol

Some chemical manufacturers commented that they believe that the amount of 2,4,6-tri-tert-butylphenol that would be released to the environment, and thus potentially cause adverse effects, is extremely limited. They also requested that more study be undertaken before risk management is developed that would involve virtual elimination of 2,4,6-tri-tert-butylphenol, a substance only present in Canada as an impurity.

Response: It is agreed that the releases of 2,4,6-tri-tert-butylphenol to the environment are estimated to be relatively low. The draft screening assessment report presented a realistic worst-case scenario based upon information submitted in the section 71 survey and other sources. The anticipated release of 2,4,6-tri-tert-butylphenol is a combination of small releases to different media (i.e. a 0.1% loss to soil, a 1.6% loss to air and a 0.3% loss to water, for a total loss of 2.0%). These releases are anticipated to occur throughout the life cycle of the substance at different stages of use. Although the estimated releases of 2,4,6-tri-tert-butylphenol are small, Environment Canada and Health Canada conclude that this substance met the criteria for persistence (P) and bioaccumulation (B), and inherent toxicity (iT) and potential for release to the environment. Because the unpredicted long-term risk and the accumulations of 2,4,6-tri-tert-butylphenol may be widespread and are difficult to reverse, a conservative response to uncertainty is justified. Therefore, this substance meets the criteria of section 64 of CEPA 1999.

Comments received following publication of the proposed order in the Canada Gazette, Part I

On May 16, 2009, the Ministers published a proposed Order Adding Toxic Substances to Schedule 1 to the Canadian Environmental Protection Act, 1999 in the Canada Gazette, Part I, for a 60-day public comment period. Below is a summary of comments received and responses relevant to the proposed addition of the seven substances to the List of Toxic Substances in Schedule 1 of CEPA 1999. No comments were received for thiourea, isoprene, 2,4,6-tri-tert-butylphenol and epichloroydrin.

C.I. Pigment Yellow 34 and C.I. Pigment Red 104

One industry association indicated that there was not sufficient evidence to support the conclusions of the assessments and that the conclusions overstate the potential risks posed by these substances.

Response: Within the Challenge, genotoxic carcinogens have constantly been treated as non-threshold toxicants based on the assumption that there is a probability of harm at any level of exposure to the substance. Therefore, even when exposure of the general population to these substances is expected to be low, C.I. Pigment Yellow 34 and C.I. Pigment Red 104 have been proposed to be harmful to human health at any level of exposure. Also, a weight-of-evidence-based approach was applied in the analysis of complex carcinogenicity and genotoxicity data for these pigments. This approach is consistent with the approach taken for all Challenge substances assessed to date.

D4 and D5

An industry association filed a notice of objection with respect to the conclusion of the assessments on siloxanes and requested the establishment of a Board of Review on the conclusion of the scientific assessments.

Response: The notice of objection and the information provided does not bring forth any new scientific data or information that would likely lead to a different conclusion respecting the potential for ecological harm posed by D4 as detailed in the final screening assessment report published on January 31, 2009. Therefore, the Ministers have decided not to establish a Board of Review for D4. For D5, scientific information respecting the substance has been made available since the conduct and publication of the final screening assessment, a Board of Review has been established to inquire into the nature and the extent of the danger posed by the substance (see Web site mentioned earlier). The report and recommendations of the board of review will be made public immediately upon receipt.

Two non-governmental organisations noted that precaution should have been more strongly applied when concluding on potential human health and ecological concerns and determination of persistence and bioaccumulation characteristics.

Response: The final assessments concluded that D4 may be causing harm to the environment but does not constitute a danger to human health. It was additionally concluded that D4 met the criteria for persistence as defined in the Regulations, but it was not concluded, based on the information available at this time, that it met the criteria for bioaccumulation. These conclusions were based on all available evidence and with full recognition of areas of uncertainty. It was also concluded that D4 does not pose a risk to human health.

An industry association believes that further actions on D4, including addition to the List of Toxic Substances under Schedule 1 of CEPA 1999, should be delayed until additional data on this substance becomes available.

Response: It was concluded that D4 poses a risk to the environment in Canada since concentrations in the environment near some discharge points from industrial operations and municipal wastewater treatment plants are believed to be sufficiently high to cause harm to sensitive organisms. This concern is not dependent on the bioaccumulation potential of D4.

Implementation, enforcement and service standards

The Order adds the seven above-mentioned substances to Schedule 1 of CEPA 1999, thereby allowing the Ministers to publish proposed regulations or instruments no later than January 2011 and finalize them no later than July 2012. Developing an implementation plan or a compliance strategy or establishing service standards are not considered necessary without any specific risk management proposals. An appropriate assessment of implementation, compliance and enforcement will be undertaken during the development of a proposed regulation or control instrument(s) respecting preventive or control actions for these substances.

Contacts

David Morin
Program Development and Engagement Division
Environment Canada
Gatineau, Quebec
K1A 0H3
Telephone: 819-953-3091
Fax: 819-953-7155
Email: Substances@ec.gc.ca

Tina Green
Risk Management Bureau
Health Canada
Ottawa, Ontario
K1A 0K9
Telephone: 613-948-2585
Fax: 613-952-8857
Email: tina.green@hc-sc.gc.ca

Footnote a
S.C. 2004, c. 15, s. 31

Footnote b
S.C. 1999, c. 33

Footnote c
S.C. 1999, c. 33

Footnote 1
S.C. 1999, c. 33

Footnote 2
Data for all substances in this document on manufacture and imports have been taken from responses to section 71 notices of CEPA 1999.

Footnote 3
The Persistence and Bioaccumulation Regulations set the criteria which are used to determine if a substance is persistent or bioaccumulative under CEPA 1999.