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Vol. 144, No. 5 — January 30, 2010

Suppliment

DEPARTMENT OF THE ENVIRONMENT

DEPARTMENT OF HEALTH

CANADIAN ENVIRONMENTAL PROTECTION ACT, 1999

Publication after Screening Assessment of Substances — Batch 8

CAS No. 79-46-9
CAS No. 88-72-2
CAS No. 17540-75-9
CAS No. 72102-55-7
CAS No. 626-39-1
CAS No. 944-61-6
CAS No. 65140-91-2
CAS No. 68551-44-0
CAS No. 75-52-5
CAS No. 139-13-9
CAS No. 2215-35-2
CAS No. 70331-94-1
CAS No. 75768-65-9

Publication of Results of Investigations and Recommendations for a Substance

CAS No. 25013-16-5

Publication after screening assessment of a substance — Propane, 2-nitro- (2-nitropropane), CAS No. 79-46-9 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Propane, 2-nitro- (2-nitropropane) is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of the draft Screening Assessment conducted on 2-nitropropane pursuant to section 74 of the Act is annexed hereby; and

Whereas it is proposed to conclude that 2-nitropropane meets one or more of the criteria set out in section 64 of the Act,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to recommend to Her Excellency the Governor in Council that 2-nitropropane be added to Schedule 1 to the Act.

Notice is furthermore given that the Ministers of the Environment and of Health have released a risk management scope document for this substance to initiate discussions with stakeholders on the development of a risk management approach.

Public comment period

As specified under subsection 77(5) of the Canadian Environmental Protection Act, 1999, any person may, within 60 days after publication of this notice, file with the Minister of the Environment written comments on the measure the Ministers propose to take and on the scientific considerations on the basis of which the measure is proposed. More information regarding the scientific considerations may be obtained from the Government of Canada’s Chemical Substances Web site (www. chemicalsubstances.gc.ca). All comments must cite the Canada Gazette, Part I, and the date of publication of this notice and be sent to the Executive Director, Program Development and Engagement Division, Gatineau, Quebec K1A 0H3, 819-953-7155 (fax), Existing.Substances.Existantes@ec.gc.ca (email).

In accordance with section 313 of the Canadian Environmental Protection Act, 1999, any person who provides information in response to this notice may submit with the information a request that it be treated as confidential.

GEORGE ENEI
Acting Director General
Science and Risk Assessment Directorate
On behalf of the Minister of the Environment

MARGARET KENNY
Director General
Chemicals Sector Directorate
On behalf of the Minister of the Environment

KAREN LLOYD
Director General
Safe Environments Directorate
On behalf of the Minister of Health

ANNEX

Summary of the Screening Assessment of Propane, 2-nitro-

Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment of Propane, 2-nitro-, also known as 2-nitropropane, Chemical Abstracts Service Registry No. 79-46-9. This substance was identified in the categorization of the Domestic Substances List as a high priority for action under the Challenge. The substance 2-nitropropane was identified as a substance presenting an intermediate potential for exposure of individuals in Canada and had been classified by other agencies on the basis of carcinogenicity. Although 2-nitropropane did meet the criteria for persistence, it did not meet criteria for bioaccumulation or inherent toxicity to aquatic organisms; thus, the focus of this assessment relates primarily to human health aspects.

According to data submitted in response to section 71 of CEPA 1999, no companies in Canada reported manufacturing 2-nitropropane in a quantity greater than or equal to the threshold of 100 kg for the 2006 calendar year. According to information submitted by Canadian companies, the total quantity imported into Canada in 2006 was between 100 and 1 000 kg. Potential sources of exposure identified in the publicly available literature include residual concentrations in vegetable oils for human consumption and pharmaceutical products, as well as formulated products including inks, paints, adhesives, varnishes, polymers, and synthetic materials that may contain 2-nitropropane.

The most significant sources of potential exposure to 2-nitropropane are likely to include inhalation of cigarette smoke and possibly the ingestion of vegetable oil that may contain residual concentrations of this substance. However, based on recent discussions that Health Canada has had with its stakeholders, 2-nitropropane is not used in vegetable oil processing in North America and, indeed, its use as a food processing solvent is discouraged internationally.

Other potential sources include food packaging and therapeutic products that may contain residual concentrations. However, there have been no recent food packaging submissions received by Health Canada’s Food Directorate that include the use of 2-nitropropane. Therefore, it is likely that 2-nitropropane has been replaced by other alternative solvents in food packaging applications.

The information available suggests that use of 2-nitropropane in paints and coatings is limited to a few specific industrial applications, thus no consumer scenarios for use of paints and coatings were generated. The exposure of the general population as a result of industrial use of 2-nitropropane within Canada is likely to be negligible.

Based principally on weight-of-evidence-based assessments of international and other national agencies, the critical effect for the characterization of risks to human health from exposure to 2-nitropropane is carcinogenicity. Increased incidence of liver tumours in experimental animals was reported in various studies. The substance 2-nitropropane induced benign and malignant liver tumours in rats in an oral study as well as multiple hepatocellular carcinomas in rats in an inhalation study. Metastases were also observed in the lungs of exposed animals. In addition, 2-nitropropane showed initiating activity in rat liver through intraperitoneal injection or inhalation exposures. The substance 2-nitropropane has also demonstrated clear evidence of genotoxicity in the liver of rats, the same organ where tumours were found. Furthermore, studies have shown that the anionic form of 2-nitropropane, propane 2-nitronate, directly interacts with genetic material in the liver of rodents, and the enzymes that activate the metabolism in rodents also exist in human organs. The International Agency for Research on Cancer has also concluded that propane 2-nitronate may act as an intermediate in the mechanism by which 2-nitropropane exerts its genotoxic and carcinogenic effects.

On the basis of the carcinogenic potential of 2-nitropropane, for which there may be a probability of harm at any exposure level, it is proposed to conclude that 2-nitropropane is a substance that 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.

The substance 2-nitropropane meets the criteria for persistence in air, water, soil, and sediment as set out in the Persistence and Bioaccumulation Regulations. In addition, 2-nitropropane does not meet the bioaccumulation criteria as set out in these Regulations. Furthermore, it is expected to have a low potential for toxicity to aquatic organisms. Based on this information, and the expected low environmental concentrations, it is concluded that 2-nitropropane 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.

This substance will be included in the Domestic Substances List inventory update initiative. In addition and where relevant, research and monitoring will support verification of assumptions used during the screening assessment and, where appropriate, the performance of potential control measures identified during the risk management phase.

Proposed conclusion

Based on the information available, it is proposed to conclude that 2-nitropropane meets one or more of the criteria set out in section 64 of CEPA 1999.

The draft Screening Assessment as well as the proposed risk management scope document for this substance is available on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances.gc.ca).

Publication after screening assessment of a substance — Benzene, 1-methyl-2-nitro- (2-nitrotoluene), CAS No. 88-72-2 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Benzene, 1-methyl-2-nitro- (2-nitrotoluene) is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of the draft Screening Assessment conducted on 2-nitrotoluene pursuant to section 74 of the Act is annexed hereby; and

Whereas it is proposed to conclude that 2-nitrotoluene meets one or more of the criteria set out in section 64 of the Act,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to recommend to Her Excellency the Governor in Council that 2-nitrotoluene be added to Schedule 1 to the Act.

Public comment period

ANNEX

Summary of the Screening Assessment of Benzene, 1-methyl-2-nitro-

The Ministers of the Environment and of Health have conducted a screening assessment of Benzene, 1-methyl-2-nitro- (2-nitrotoluene), Chemical Abstracts Service Registry No. 88-72-2. This substance was identified in the categorization of the Domestic Substances List (DSL) as a high priority for action under the Challenge. The substance 2-nitrotoluene was identified as presenting an intermediate potential for exposure of individuals in Canada and had been classified by other agencies on the basis of carcinogenicity and genotoxicity. The substance did meet the ecological categorization criteria for persistence, but did not meet the ecological criteria for bioaccumulation potential or inherent toxicity to aquatic organisms. Although an ecological risk assessment has been prepared, the focus of this assessment of 2-nitrotoluene relates to human health risks.

The substance 2-nitrotoluene does not occur naturally in the environment. It is an organic substance that is found in Canada and elsewhere primarily as a chemical intermediate in a variety of industries. Under information reported pursuant to section 71 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the total quantity of 2-nitrotoluene imported into and used in Canada in 2006 was between 100 and 1 000 kg, while no manufacturing was reported. The quantities of 2-nitrotoluene imported and used in Canada indicate that it could potentially be released into the Canadian environment. The general population is not likely to be exposed to 2-nitrotoluene, since it is used in industrial applications and the only reported Canadian use was in the explosives industry and the related products are not intended for the general public.

Exposures of the general population to 2-nitrotoluene through the environmental media (air, drinking water, and soil) are expected to be negligible. It is not expected to be found in food and beverages. Based upon the information obtained on current uses of 2-nitrotoluene in Canada, exposure to the general population is expected to be negligible.

As 2-nitrotoluene was classified on the basis of carcinogenicity by other national and international agencies, carcinogenicity was a key focus for this screening assessment.

Increased incidence of tumours was reported in multiple tissues such as the mesothelial tissues (tunica vaginalis of the testis, epidydymis, abdominal wall or surface of abdominal organs), skin (subcutaneous tissues), mammary gland, liver and lungs in rats exposed via the diet. Tumours in the circulatory system, large intestines and the liver were reported in mice exposed via the dietary route as well. The substance 2-nitrotoluene was genotoxic in a range of in vitro and in vivo assays, notably clastogenic in human peripheral lymphocytes and forming deoxyribonucleic acid (DNA) adducts in exposed rodents. While the mode of induction of tumours has not been fully elucidated, based on the genotoxicity of 2-nitrotoluene, the tumours observed in the experimental animals are considered to have resulted from direct interaction with genetic material.

Exposure to 2-nitrotoluene has also been associated with non-cancer effects in experimental animals including developmental and reproductive effects, as well as effects in the lungs, liver, spleen, bone marrow and the hematopoietic system. Margins of exposures were not calculated for non-cancer effects in this assessment since non-cancer effects occurred at a dose level at which tumours were observed and because the available information indicates that exposures to 2-nitrotoluene in the Canadian general population from either environmental media or consumer products is expected to be negligible.

On the basis of the carcinogenic potential of 2-nitrotoluene, for which there may be a probability of harm at any exposure level, it is proposed to conclude that 2-nitrotoluene is a substance that 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.

Based on available empirical data model results, 2-nitrotoluene is expected to be persistent but is not expected to bioaccumulate in the environment. The substance therefore does meet the persistence criteria but not the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations. In addition, available empirical data suggest that the substance poses a moderate hazard to aquatic organisms. Based on a comparison of predicted non toxic effect concentrations and estimated reasonable worst-case environmental exposure concentrations, it is considered unlikely that Benzene, 1-methyl-2-nitro- (2-nitrotoluene) is causing ecological harm in Canada.

Based on the information available, it is proposed to conclude that 2-nitrotoluene 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.

Proposed conclusion

Based on the information available, it is proposed to conclude that 2-nitrotoluene meets one or more of the criteria set out in section 64 of CEPA 1999.

Publication after screening assessment of a substance — Phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)-, CAS No. 17540-75-9 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)- is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of the draft Screening Assessment conducted on Phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)- pursuant to section 74 of the Act is annexed hereby;

Whereas it is proposed to conclude that Phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)- meets one or more of the criteria set out in section 64 of the Act; and

Whereas the Ministers are satisfied that the criteria set out under subsection 77(4) of the Act are met,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to recommend to Her Excellency the Governor in Council that Phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)- be added to Schedule 1 to the Act.

Notice therefore is further given that the Ministers of the Environment and of Health propose the implementation of virtual elimination of Phenol, 2,6-bis(1,1-dimethylethyl)-4(1-methylpropyl)- under subsection 65(3) of the Act.

Public comment period

ANNEX

Summary of the Screening Assessment of Phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)-

Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment on Phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)- (DTBSBP), Chemical Abstracts Service Registry No. 17540-75-9. This substance was identified as a high priority for screening assessment and included in the Challenge because it was found to meet the ecological categorization criteria for persistence, bioaccumulation potential and inherent toxicity to non-human organisms and is believed to be in commerce in Canada.

The substance DTBSBP was not considered to be a high priority for assessment of potential risks to human health, based upon application of the simple exposure and hazard tools developed by Health Canada for categorization of substances on the Domestic Substances List. Therefore, this assessment focuses on information relevant to the evaluation of ecological risks.

The substance DTBSBP is an organic substance that is used in Canada and elsewhere as an antioxidant and liquid stabilizer in plastics such as poly(vinyl chloride) [PVC] and polyurethane, as well as in brake fluids, ink resins and mineral/vegetable oils used in industrial applications. It is also used as an antioxidant in the petrochemical sector. This substance is not naturally produced in the environment. A quantity of 16 686 kg of DTBSBP was imported into Canada in 2006, for use mainly in plastics manufacturing. The quantity of DTBSBP imported into Canada, along with the potentially dispersive uses of this substance, indicates that it may be released into the Canadian environment.

Based on reported use patterns and certain assumptions, 54% of DTBSBP ends up in waste disposal sites. Small proportions are estimated to be released to water (3.7%), paved/unpaved surfaces (0.2%) and air (0.4%). DTBSBP has a low solubility in water, is moderately volatile and has a tendency to partition to particles and to the lipids (fat) of organisms because of its hydrophobic nature. DTBSBP will likely be found equally in sediments (51%) and water (48%) when released to water. It is not expected to be subject to long-range atmospheric transport.

Based on its physical and chemical properties as well as on empirical biodegradation data, DTBSBP is not expected to degrade quickly in the environment. It is, therefore, persistent in water, soil and sediments. DTBSBP also has the potential to accumulate in organisms and may biomagnify in food chains. The substance has been determined to meet the persistence and bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations. In addition, modelled and analogue aquatic toxicity data indicate that the substance is potentially highly hazardous to aquatic organisms.

There was no empirical data identified regarding measured concentrations of DTBSBP in environmental media in Canada or elsewhere. DTBSBP may be used in plasticized PVC for food packaging applications. A conservative exposure estimate derived from the potential use of plasticized PVC films in food packaging was considered. Overall, it is expected that exposure to DTBSBP through dietary intake, if any, in Canada would be minimal. Exposure to DTBSBP of the general population in Canada was examined by considering polyol and polyurethane foam products in mattresses, furniture, and automotive trim materials. Due to the lack of experimental data on DTBSBP, exposure estimates were derived based on the structurally similar but more volatile antioxidant butylated hydroxytoluene. This likely resulted in overestimates which can be considered as conservative upper-bounding estimates.

The health effects database for DTBSBP is limited; however, the substance was not genotoxic in in vitro assays and one study suggests low acute toxicity. Information on analogues indicates that liver and hematological effects are common endpoints which are observed across this group of compounds.

Based on the information available, the margins between upper-bounding estimates of exposure through food (i.e. migration from food packaging) and consumer products and levels associated with effects in experimental animals are considered to be adequately protective.

Given that long-term risks associated with persistent and bioaccumulative substances cannot at present be predicted reliably, quantitative risk estimates have limited relevance. Furthermore, since accumulations of such substances may be widespread and are difficult to reverse, a conservative response to uncertainty is justified.

Based on the information available, it is proposed to conclude that DTBSBP is 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.

Proposed conclusion

Based on the information available, it is proposed to conclude that DTBSBP meets one or more of the criteria set out in section 64 of CEPA 1999. DTBSBP is persistent and bioaccumulative as set out in the Persistence and Bioaccumulation Regulations, and its presence in the environment results primarily from human activity.

Publication after screening assessment of a substance — Methylium, [4-(dimethylamino)phenyl]bis[4-(ethylamino)-3-methylphenyl]-, acetate, CAS No. 72102-55-7 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Methylium, [4-(dimethylamino)phenyl]bis[4-(ethylamino)-3-methylphenyl]-, acetate is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of the draft Screening Assessment conducted on Methylium, [4-(dimethylamino)phenyl]bis[4-(ethylamino)-3-methylphenyl]-, acetate pursuant to section 74 of the Act, is annexed hereby; and

Whereas it is proposed to conclude that Methylium, [4-(dimethylamino) phenyl]bis[4-(ethylamino)-3-methylphenyl]-, acetate meets one or more of the criteria set out in section 64 of the Act,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to recommend to Her Excellency the Governor in Council that Methylium, [4-(dimethylamino) phenyl]bis[4-(ethylamino)-3-methylphenyl]-, acetate be added to Schedule 1 to the Act.

Public comment period

ANNEX

Summary of the Screening Assessment of Methylium, [4-(dimethylamino)phenyl]bis[4-(ethylamino)-3methylphenyl]-, acetate

Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment on Methylium, [4-(dimethylamino)phenyl]bis[4-(ethylamino)-3-methylphenyl]-, acetate (MAPBAP acetate), Chemical Abstracts Service Registry Number 72102-55-7. This substance was identified as a high priority for screening assessment and included in the Challenge because it was found to meet the ecological categorization criteria for persistence, bioaccumulation potential and inherent toxicity to non-human organisms, and is believed to be in commerce in Canada.

The substance MAPBAP acetate was not considered to be a high priority for assessment of potential risks to human health, based upon application of the simple exposure and hazard tools developed by Health Canada for categorization of substances on the Domestic Substances List. Therefore, this assessment focuses on information relevant to the evaluation of ecological risks.

The substance MAPBAP acetate is an organic substance that is used in Canada and elsewhere as a cationic dye mainly in the production of paper products. The substance is not naturally produced in the environment. Between 10 001 and 100 000 kg of MAPBAP acetate were imported into Canada in 2006. The quantity of MAPBAP acetate imported into Canada, along with the known uses of this substance, indicate that it could be released into the Canadian environment.

Based on reported use patterns and certain assumptions, most of the substance ends up in wastewater, is disposed of in landfills, or is recycled. Based on its physical and chemical properties and its partitioning behaviour, MAPBAP acetate could be found in water, sediments or soil. It is not expected to be significantly present in air.

Based on its physical and chemical properties, MAPBAP acetate is not expected to degrade quickly in the environment. It is persistent in water, soil and sediments. MAPBAP acetate meets the criteria for persistence, but not bioaccumulation potential, as set out in the Persistence and Bioaccumulation Regulations. In addition, modelled and read-across acute aquatic toxicity values indicate that MAPBAP acetate is potentially highly hazardous to aquatic organisms.

Although no releases of MAPBAP acetate were reported in response to a survey under section 71 of CEPA 1999, releases to the environment could occur given the substance’s current use as a paper dye. A site-specific risk quotient analysis was performed for the aquatic medium at 11 industrial sites to determine whether there is potential for ecological harm in Canada. The site-specific analysis yielded a predicted environmental concentration (PEC) exceeding 0.001 mg/L for 10 of the 11 the sites analyzed. When these concentrations were compared to the experimental read-across predicted no-effect concentration (PNEC), the resulting risk quotients (PEC/PNEC) exceeded 1 at 10 of the 11 sites.

The potential for exposure of the general population to MAPBAP acetate from environmental media is expected to be negligible. Exposure to MAPBAP acetate from consumer products (newsprint dye) is expected to be negligible for the intended purpose of the product (negligible dermal exposure from reading activities) and low for incidental events such as mouthing exposure by toddlers.

As exposure of the general population in Canada based on the use of the substance as a paper dye is expected to be low to negligible, the risk to human health is considered to be low.

No empirical data were identified for MAPBAP acetate. The outputs of quantitative structure-activity relationship predictions for carcinogenicity and genotoxicity were mixed. Information from analogues suggests possible flags for carcinogenicity, genotoxicity and developmental toxicity.

Based on read-across and modelled data for persistence, bioaccumulation and aquatic toxicity, and the characterization of risk to aquatic organisms, it is proposed to conclude that MAPBAP acetate is 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.

Proposed conclusion

Based on the information available, it is proposed to conclude that MAPBAP acetate meets one or more of the criteria set out in section 64 of CEPA 1999.

Publication after screening assessment of four substances — Benzene, 1,3,5-tribromo-, CAS No. 626-39-1; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy, CAS No. 944-61-6; Phosphonic acid, [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]-, monoethyl ester, calcium salt (2:1), CAS No. 65140-91-2; and Fatty acids, C_6-19-branched, zinc salts, CAS No. 68551-44-0 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy-; Phosphonic acid, [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]-, monoethyl ester, calcium salt (2:1); and Fatty acids, C_6-19-branched, zinc salts are substances on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of a draft Screening Assessment conducted on Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy-; Phosphonic acid, [[3,5-bis(1,1-dimethylethyl)4-hydroxyphenyl]methyl]-, monoethyl ester, calcium salt (2:1); and Fatty acids, C_6-19-branched, zinc salts pursuant to section 74 of the Act is annexed hereby;

Whereas the Ministers of the Environment and of Health have identified no manufacture or importation activity for Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy-; Phosphonic acid, [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl] methyl]-, monoethyl ester, calcium salt (2:1); and Fatty acids, C_6-19-branched, zinc salts above 100 kg per calendar year;

Whereas it is proposed to conclude that Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy-; Phosphonic acid, [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl] methyl]-, monoethyl ester, calcium salt (2:1); and Fatty acids, C_6-19-branched, zinc salts do not meet any of the criteria set out in section 64 of the Act; and

Whereas the Minister of the Environment intends to amend the Domestic Substances List, under subsection 87(3) of the Act, to indicate that subsection 81(3) thereof applies with respect to Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy-; Phosphonic acid, [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]-, monoethyl ester, calcium salt (2:1); and Fatty acids, C_6-19-branched, zinc salts.

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to take no further action on Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy-; Phosphonic acid, [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl] methyl]-, monoethyl ester, calcium salt (2:1); and Fatty acids, C_6-19-branched, zinc salts at this time under section 77 of the Act.

Public comment period

ANNEX

Summary of the Draft Screening Assessment of the four substances listed below

CAS RN*	DSL Name
626-39-1	Benzene, 1,3,5-tribromo-
944-61-6	Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy-
65140-91-2	Phosphonic acid, [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]-, monoethyl ester, calcium salt (2:1)
68551-44-0	Fatty acids, C_6-19-branched, zinc salts
*CAS RN = Chemical Abstracts Service Registry Number

The above four substances on the Domestic Substances List (DSL) were identified as high priorities for screening assessment, to be part of the Challenge, because they met the ecological categorization criteria for persistence (P) and bioaccumulation (B) and inherent toxicity to non-human organisms (iT), under paragraph 73(1)(b) of the Canadian Environmental Protection Act, 1999 (CEPA 1999), and were believed to be in commerce in Canada. However, these substances were not identified as posing a high hazard to human health based on classifications by other national or international agencies for carcinogenicity, genotoxicity, developmental toxicity or reproductive toxicity. Also, they are not on the European Union’s Candidate List of Substances of Very High Concern for Authorisation.

Pursuant to paragraph 74(a) of CEPA 1999, the Ministers of the Environment and of Health have conducted a screening assessment on the four substances.

Results from notices issued under paragraph 71(1)(b) of CEPA 1999 in January 2009 revealed no reports of industrial activity (import or manufacture) with respect to these substances in Canada, equal or above the reporting threshold of 100 kg, for the 2006 reporting year. These results suggest that these substances are currently not in use above the specified reporting threshold, and therefore the likelihood of exposure to humans or the environment of these substances in Canada resulting from commercial activity is low.

Information received as a result of the above notices issued under paragraph 71(1)(b) of CEPA 1999 and the accompanying questionnaire of January 2009 also revealed no significant new data relevant to the PBiT properties of these four substances. Given the lack of any significant commercial activity for these substances, no additional efforts have been made to collect or analyze information relevant to the persistence, bioaccumulation and ecological effects of these four substances beyond what was done for categorization. Therefore, the decisions on PBiT properties made during categorization remain unchanged. The substances are considered to be inherently toxic to non-human organisms. They also meet the criteria for both persistence and bioaccumulation as set out in the Persistence and Bioaccumulation Regulations.

Proposed conclusion

Based on available information, it is concluded that Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy-; Phosphonic acid, [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl] methyl]-, monoethyl ester, calcium salt (2:1); and Fatty acids, C_6-19-branched, zinc salts do not meet any of the criteria set out in section 64 of CEPA 1999.

Because these substances are listed on the Domestic Substances List, their import and manufacture in Canada are not subject to notification under subsection 81(1). Given the hazardous properties of these substances, there is concern that new activities that have not been identified or assessed could lead to these substances meeting the criteria set out in section 64 of the Act. Therefore, it is recommended to amend the Domestic Substances List, under subsection 87(3) of the Act, to indicate that subsection 81(3) of the Act applies with respect to these substances so that new manufacture, import or use of these substances is notified and undergoes ecological and human health risk assessments.

The draft Screening Assessment for these substances is available on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances.gc.ca).

Publication after screening assessment of a substance — Methane, nitro- (nitromethane), CAS No. 75-52-5 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Methane, nitro- (nitromethane) is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of the draft Screening Assessment conducted on nitromethane pursuant to section 74 of the Act is annexed hereby; and

Whereas it is proposed to conclude that nitromethane does not meet any of the criteria set out in section 64 of the Act,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to take no further action on nitromethane at this time under section 77 of the Act.

Public comment period

ANNEX

Summary of the Screening Assessment Report of Methane, nitro-

The Ministers of the Environment and of Health have conducted a screening assessment of Methane, nitro- (nitromethane), Chemical Abstracts Service Registry No. 75-52-5. This substance was identified in the categorization of the Domestic Substances List as a high priority for action under the Challenge. Nitromethane was identified as a high priority because it was considered to pose intermediate potential for exposure of individuals in Canada and had been classified on the basis of carcinogenicity. Although nitromethane met the ecological categorization criteria for persistence, it did not meet the criteria for bioaccumulation potential or inherent toxicity to aquatic organisms. Therefore, the focus of this assessment of nitromethane relates primarily to human health risks.

In response to a notice issued under section 71 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), nitromethane was not reported to be manufactured at a quantity above the reporting threshold of 100 kg in 2006. Importation activities (whether alone, in a mixture, in a product or in manufactured items) were reported to be in the range of 100–1 000 kg in 2006. Nitromethane’s principal uses that have been identified as potentially ongoing in Canada as of the 2006 reporting year were use as a fuel additive for drag racing cars and model engines, laboratory and industrial solvent, chemical intermediate in the synthesis of biocides, chemicals, agricultural products and other intermediates, stabilizer in degreaser, carrier solvent for opaquing porcelain for dental manufacturing applications, adhesive remover, dry cleaning solvent stabilizer, and formulant in flux remover, magnetic tape head cleaner and multi-purpose lubricant.

Population exposure to nitromethane through environmental media is expected to be low, based on minimal data identified and negligible environmental releases of nitromethane in Canada during the 2006 calendar year as reported in responses to a notice issued under section 71 of CEPA 1999. Emissions of nitromethane in the ambient environment are expected to be primarily from anthropogenic sources. Inhalation constitutes the principal route of environmental exposure. Although there are only very limited consumer products available containing nitromethane, subpopulation exposure is anticipated through off-gassing from some products (i.e. instant adhesive remover, false nail remover and eyelash adhesive remover). Potential exposure was estimated for false nail remover using available data and represents an upper-bound exposure potential from consumer products.

As nitromethane was classified on the basis of carcinogenicity by other national and international agencies, carcinogenicity was a key focus for this screening assessment. Following exposure to nitromethane via inhalation, tumours were observed at multiple organ sites in mice and at one site in female rats. Nitromethane is not genotoxic in in vitro or in vivo assays. Although the mode of action for carcinogenicity has not been elucidated, the tumours observed are not considered to have resulted from direct interaction with genetic material. Therefore, a threshold approach is used to characterize risk to human health. Other adverse health effects observed in experimental animals include reproductive toxicity, hyaline droplet formation in the respiratory epithelium and neurotoxicity.

The margins between a conservative upper-bounding estimate of exposure to nitromethane from air and the levels associated with effects in experimental animals are considered to be adequately protective. The margins between a conservative upper-bounding estimate of exposure from false nail remover and levels associated with effects in experimental animals and humans are considered to be adequately protective.

On the basis of the adequacy of the margins between exposure to nitromethane in ambient air or consumer products and critical effect levels in experimental animals and humans, it is proposed to conclude that nitromethane 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.

Nitromethane meets the criteria for persistence but not the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations. Furthermore, it is expected to have a low potential for toxicity to aquatic organisms. Based on this information and the expected low environmental concentrations, it is proposed to conclude that nitromethane 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.

Proposed conclusion

Based on the information available, nitromethane does not meet any of the criteria set out in section 64 of CEPA 1999.

The draft Screening Assessment for this substance is available on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances.gc.ca).

Publication after screening assessment of a substance — Glycine, N,N-bis(carboxymethyl)-, CAS No. 139-13-9 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Glycine, N,N-bis(carboxymethyl)- is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of the draft Screening Assessment conducted on Glycine, N,N-bis(carboxymethyl)- pursuant to section 74 of the Act is annexed hereby; and

Whereas it is proposed to conclude that Glycine, N,N-bis(carboxymethyl)- does not meet any of the criteria set out in section 64 of the Act,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to take no further action on Glycine, N,N-bis(carboxymethyl)- at this time under section 77 of the Act.

Public comment period

ANNEX

Summary of the Screening Assessment of Glycine, N,N-bis(carboxymethyl)-

Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment of Glycine, N,N-bis(carboxymethyl)-, commonly referred to as nitrilotriacetic acid or NTA, Chemical Abstracts Service Registry Number 139-13-9. This substance was identified in the categorization of the Domestic Substances List as a high priority for action under the Challenge. NTA was identified as a high priority as it was determined to present intermediate potential for exposure of individuals in Canada and is considered to pose a high hazard to human health. Although NTA met the ecological categorization criteria for persistence, it did not meet the criteria for bioaccumulation potential or inherent toxicity to aquatic organisms. Therefore, the focus of this assessment of NTA relates primarily to human health risks. Information relating to the sodium salts of NTA is also considered in this screening assessment because the toxicological endpoints of NTA and its sodium salts are similar and because the dissociation of NTA and its sodium salts leads to a common moiety. However, the conclusion of this screening assessment pertains to NTA only; the data presented relating to the sodium salts of NTA serves only as supporting information.

According to data submitted in response to section 71 of CEPA 1999, no companies in Canada reported manufacturing NTA in a quantity greater than or equal to the reporting threshold of 100 kg for the 2006 calendar year. However, it was reported that NTA was imported into Canada in the range of 1 000–10 000 kg in that year. The total quantity of NTA (including its salts) imported in 2006, as reported by another source, was 3.9 million kilograms. Available scientific and technical information and responses to the section 71 survey indicated that the major use of NTA in Canada is in institutional and industrial cleaning products. Other applications of NTA in Canada involve its function as a chelating agent in a variety of industrial processes, such as the industrial treatment of boiler water and pulp and paper processing to produce paper and paperboard products. Previously, the trisodium salt of NTA (Na₃NTA) was used heavily as a builder in laundry detergents. Currently, the major use of this salt in Canada lies also in institutional and industrial applications. Na₃NTA is a non-active ingredient in Canadian pesticide formulations and has been found in a limited number of Canadian personal care products.

Emissions of NTA and its salts into the ambient environment are expected to be primarily from anthropogenic activities. NTA and its salts have been measured in Canadian municipally treated drinking water, groundwater and industrial water. Exposures of the general population to NTA via intake of drinking water and use of consumer products are estimated to be low.

High concentrations of NTA induced primary tumours at several locations in the urinary tract after administration in the diet or in drinking water in long-term rat and mouse studies. Transitional cell epithelial tumours were observed in the kidney, ureter and urinary bladder, while tubular cell tumours were observed in the kidney. In short-term to chronic repeated-dose studies in experimental animals exposed orally to NTA, non-neoplastic lesions were often observed in the kidney, ureters and urinary bladder. Consideration of the available information regarding genotoxicity indicates that NTA is not likely to be genotoxic. Accordingly, although the mode of induction of tumours is not fully elucidated, the tumours observed are not considered to have resulted from direct interaction with genetic material. Therefore, a threshold approach is used to assess risk to human health.

Based on the comparison of estimated exposures to NTA in Canada with the critical effect levels, and taking into account the uncertainties in the databases on exposure and effects, it is considered that the resulting margins of exposure are adequately protective of human health for non-cancer effects.

Based on the available information on its potential to cause harm to human health, it is proposed to conclude that NTA 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.

Ecological exposure scenarios were developed based on the information on commercial use to estimate releases into the aquatic environment from industrial operations and resulting aquatic concentrations. Environmental concentrations are estimated to be below those that would harm sensitive aquatic organisms. This indicates that the substance is unlikely to cause ecological harm in the aquatic environment.

Based on the information available, it is proposed to conclude that NTA 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. NTA does not meet the persistence or bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations.

Proposed conclusion

Based on the information available, NTA does not meet any of the criteria set out in section 64 of CEPA 1999.

The draft Screening Assessment for this substance is available on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances.gc.ca).

Publication after screening assessment of a substance — Zinc, bis[O,O-bis(1,3-dimethylbutyl) phosphorodithioato-S,S']-, (T-4)-, CAS No. 2215-35-2 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Zinc, bis[O,O-bis(1,3-dimethylbutyl) phosphorodithioato-S,S']-, (T-4)- is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of the draft Screening Assessment conducted on Zinc, bis[O,O-bis(1,3-dimethylbutyl) phosphorodithioato-S,S']-, (T-4)- pursuant to section 74 of the Act is annexed hereby; and

Whereas it is proposed to conclude that Zinc, bis[O,O-bis(1,3-dimethylbutyl) phosphorodithioato-S,S']-, (T-4)- does not meet any of the criteria set out in section 64 of the Act,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to take no further action on Zinc, bis[O,O-bis(1,3-dimethylbutyl) phosphorodithioato-S,S']-, (T-4)- at this time under section 77 of the Act.

Public comment period

ANNEX

Summary of the Screening Assessment of Zinc, bis[O,O-bis(1,3-dimethylbutyl) phosphorodithioato-S,S']-, (T-4)-

Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment on Zinc, bis[O,O-bis(1,3-dimethylbutyl) phosphorodithioato-S,S']-, (T-4)- (zinc BDBP), Chemical Abstracts Service Registry No. 2215-35-2. This substance was identified as a high priority for screening assessment and included in the Challenge because it had been found to meet the ecological categorization criteria for persistence, bioaccumulation potential and inherent toxicity to non-human organisms and is believed to be in commerce in Canada.

The substance zinc BDBP was not considered to be a high priority for assessment of potential risks to human health, based upon application of the simple exposure and hazard tools developed by Health Canada for categorization of substances on the Domestic Substances List. Therefore, this assessment focuses on information relevant to the evaluation of ecological risks.

Zinc BDBP is an organometallic dialkyldithiphosphate substance that is used in Canada and elsewhere as an anti-wear oil additive. It also acts as an antioxidant. The substance is not naturally produced in the environment. Between 10 000 and 100 000 kg of zinc BDBP were imported into Canada in 2005 and between 100 000 and 1 000 000 kg were imported in 2006 for use in the petroleum industry. The quantity of zinc BDBP imported into Canada indicates that it could be potentially released to the Canadian environment.

Based on reported use patterns and certain assumptions, most of the substance is transformed. Small proportions are estimated to be released to wastewater (1.9%) and to paved/unpaved surfaces (0.9%). Zinc BDBP is somewhat soluble in water, is not volatile and has a tendency to partition to particles and lipids (fat) of organisms because of its hydrophobic nature. For these reasons, zinc BDBP will be likely found mostly in sediments and soil, and to a minor extent, in water. It is not expected to be significantly present in air. It is also not expected to be subject to long-range atmospheric transport.

Based on its physical and chemical properties, zinc BDBP is expected to be persistent in the environment. New bioaccumulation predictions suggest that this substance has a low potential to accumulate in the lipid tissues of organisms. The substance therefore meets the persistence criteria but does not meet the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations. For this screening assessment, a very conservative industrial exposure scenario was selected in which an operation discharges zinc BDBP into the aquatic environment. The predicted environmental concentration in water (PEC) was one order of magnitude below the predicted aquatic no-effect concentration (PNEC) calculated from a Species Sensitivity Distribution (SSD) using data from other substances within the dialkyldithiphosphate category. Additionally, results from a consumer release scenario that estimates exposure (PECs) resulting from the down-the-drain release using very conservative assumptions indicate that the PNEC is unlikely to be exceeded. Consequently, exposure levels are not likely to exceed the aquatic PNEC in the conservative scenarios considered, whether based on consumer or industrial releases; that is, risk quotients are almost always below 1.

Based on the information available, it is proposed to conclude that zinc BDBP 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.

The potential for exposure of the general population to zinc BDBP from environmental media is expected to be negligible. However, there is potential for dermal exposure from motor oil, which is typically used in an occupational setting, but may also be used directly by consumers.

The toxicological dataset for zinc BDBP is limited; however, health effects associated with zinc BDBP dermal exposure in experimental animals includes dermal irritation, body weight loss and elevated white blood cell count and at higher exposure levels, effects on testes.

The margins between upper-bounding estimates of exposure from environmental media and consumer products (motor oil) and levels associated with effects in experimental animals are considered to be adequately protective.

This substance will be included in the upcoming Domestic Substances List inventory update initiative. In addition and where relevant, research and monitoring will support verification of assumptions used during the screening assessment.

Proposed conclusion

Based on the information available, zinc BDBP does not meet any of the criteria set out in section 64 of CEPA 1999.

The draft Screening Assessment for this substance is available on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances.gc.ca).

Publication after screening assessment of a substance — Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, (1,2-dioxo-1,2-ethanediyl)bis(imino-2,1-ethanediyl) ester (benzenepropanoic acid ester), CAS No. 70331-94-1 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, (1,2-dioxo-1,2-ethanediyl)bis(imino-2,1-ethanediyl) ester (benzenepropanoic acid ester) is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of the draft Screening Assessment conducted on benzenepropanoic acid ester pursuant to section 74 of the Act is annexed hereby; and

Whereas it is proposed to conclude that benzenepropanoic acid ester does not meet any of the criteria set out in section 64 of the Act,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to take no further action on benzenepropanoic acid ester at this time under section 77 of the Act.

Public comment period

ANNEX

Summary of the Screening Assessment Report of Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, (1,2-dioxo-1,2-ethanediyl)bis(imino-2,1-ethanediyl) ester

Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment on Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, (1,2-dioxo-1,2-ethanediyl)bis(imino-2,1-ethanediyl) ester (benzenepropanoic acid ester), Chemical Abstracts Service Registry No. 70331-94-1. This substance was identified as a high priority for screening assessment and included in the Challenge because it had been found to meet the ecological categorization criteria for persistence, bioaccumulation potential and inherent toxicity to non-human organisms and is believed to be in commerce in Canada.

The substance benzenepropanoic acid ester was not considered to be a high priority for assessment of potential risks to human health, based upon application of the simple exposure and hazard tools developed by Health Canada for categorization of substances on the Domestic Substances List. Therefore, this assessment focuses on information relevant to the evaluation of ecological risks.

Benzenepropanoic acid ester is an organic substance that is used in Canada as an antioxidant in plastics. The substance is not naturally produced in the environment. It is not reported to be manufactured in Canada; however, 153 kg were imported into Canada in 2006.

Based on reported use patterns in Canada and certain assumptions, most of the substance ends up in waste disposal sites. About 4% is estimated to be released to water, and 4% to soil. Benzenepropanoic acid ester has very low predicted water solubility. It is not volatile, and it has a tendency to partition mainly to sediments if released to surface waters, and to soils if released to soils or air.

Based on its physical and chemical properties and on data from selected chemical analogues, benzenepropanoic acid ester is persistent in the environment. It has a high modelled log K_OW value of 6.68. However, new modelled bioaccumulation data that takes into account biotransformation suggests that this substance has a low potential to accumulate in the lipid tissues of organisms. The substance therefore meets the persistence criteria but does not meet the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations.

For this screening assessment, a very conservative exposure scenario was selected in which an industrial operation (plastics manufacturer) discharges benzenepropanoic acid ester into the aquatic environment. The predicted environmental concentration in water was one order of magnitude smaller than the predicted no-effect concentration).

Exposure of the general population in Canada to benzenepropanoic acid ester from environmental media is expected to be negligible based on the limited amount imported into Canada on an annual basis. The principal source of exposure to benzenepropanoic acid ester for the general population is expected to be through food (i.e. migration from food packaging materials). However, this substance is not likely to be currently used for food packaging applications.

The human health effects database for benzenepropanoic acid ester is moderate; however, the available empirical data and information from predictive models are not suggestive of high hazard. Based on the available information, the margins between the probable daily intake estimated from food packaging materials and levels associated with effects in experimental animals are considered to be adequately protective.

Proposed conclusion

Based on the information available, benzenepropanoic acid ester does not meet any of the criteria set out in section 64 of CEPA 1999.

The draft Screening Assessment for this substance is available on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances.gc.ca).

Publication after screening assessment of a substance — Phosphonium, triphenyl(phenylmethyl)-, salt with 4,4′-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[phenol] (1:1), CAS No. 75768-65-9 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Phosphonium, triphenyl(phenylmethyl)-, salt with 4,4′-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[phenol] (1:1) is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

Whereas a summary of the draft Screening Assessment conducted on Phosphonium, triphenyl(phenylmethyl)-, salt with 4,4′-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[phenol] (1:1) pursuant to section 74 of the Act is annexed hereby; and

Whereas it is proposed to conclude that Phosphonium, triphenyl(phenylmethyl)-, salt with 4,4′-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[phenol] (1:1) does not meet any of the criteria set out in section 64 of the Act,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to take no further action on Phosphonium, triphenyl(phenylmethyl)-, salt with 4,4′-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[phenol] (1:1) at this time under section 77 of the Act.

Public comment period

ANNEX

Summary of the Screening Assessment of Phosphonium, triphenyl(phenylmethyl)-, salt with 4,4′-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[phenol] (1:1)

Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment on Phosphonium, triphenyl(phenylmethyl)-, salt with 4,4′-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[phenol] (1:1) [PTPTT], Chemical Abstracts Service Registry No. 75768-65-9. This substance was identified as a high priority for screening assessment and included in the Challenge because it had been found to meet the ecological categorization criteria for persistence, bioaccumulation potential and inherent toxicity to non-human organisms and is believed to be in commerce in Canada.

The substance PTPTT was not considered to be a high priority for assessment of potential risks to human health, based upon application of the simple exposure and hazard tools developed by Health Canada for categorization of substances on the Domestic Substances List. Therefore, this assessment focuses on information relevant to the evaluation of ecological risks.

The substance PTPTT is an organic salt that is used in Canada primarily as a cross-linking agent and vulcanization accelerator in the manufacture of fluoroelastomers, a class of synthetic rubbers used in industrial applications requiring high resistance to chemicals and heat. The substance is not naturally produced in the environment. It is not reported to be manufactured in Canada; however, between 100 and 1 000 kg of the salt were imported into the country in 2006 for use in the manufacturing of fluoroelastomer-containing products.

Based on reported use patterns and certain assumptions, in Canada most of the substance is chemically transformed during the curing process of the fluoroelastomer rubbers. About 0.1% is estimated to be released to wastewater, 0.1 % is expected to be sent to landfills, and no releases are predicted to air. PTPTT is an ionic compound which (based on new information) is expected to dissociate into a benzyltriphenyl phosphonium (BTP) cation and bisphenol AF (BPAF) if released into the aquatic environment. The BPAF component will be in a neutral form in the aquatic environment at a circum-neutral to acidic pH but will dissociate into its anionic form an alkaline pH. Because of this dissociation behaviour, the assessment of PTPTT also needs to focus on the dissociation products BTP and BPAF.

The substance PTPTT and its dissociation products present low experimental and predicted solubility in water and, in the case of BTP, moderate measured solubility in 1-octanol (920 mg/L). Upon dissociation, if released into the aquatic environment, BTP and BPAF are expected to remain largely in the water column with a likely smaller amount binding to suspended solids and settling to sediments. Neither PTPTT nor its dissociation products are volatile, and the substances are expected to be largely immobile if released to soil.

Based on their physical and chemical properties, the dissociation products of PTPTT are expected to be persistent in all media with the exception of the atmosphere. In addition, experimental data relating to the solubility of BTP in octanol and water, as well as bioaccumulation model predictions for BTP and BPAF, suggest that these substances have a low potential to accumulate in the lipid tissue of organisms. The dissociation products of PTPTT therefore meet the persistence criteria but do not meet the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations. Aquatic toxicity data for the dissociation products of PTPTT suggest that BTP has a low potential to harm aquatic organisms, but that BPAF may be harmful, depending on exposure concentrations.

Based on a very conservative exposure scenario in which an industrial operation (user of PTPTT) discharges the substance into the aquatic environment, and assuming complete PTPTT dissociation in solution, predicted environmental concentrations in water for BTP and BPAF were below predicted no-effect concentrations calculated for sensitive aquatic species.

Exposure of the general population in Canada to PTPTT from environmental media is expected to be negligible based on the limited amount imported into Canada on an annual basis, the form that it is imported in, and its use. PTPTT is imported as a component of solid-state fluoroelastomer precompounds, which are subsequently cured at fluoroelastomer-processing facilities. It is believed that PTPTT is almost fully consumed (transformed) during this process and that potential residual levels in manufactured products would be only at trace levels, leading to negligible exposure to the general population. Since very small amounts (< 1 kg) of PTPTT could be potentially released into water each year, exposure to any dissociation products would be negligible; therefore, these dissociation products were not considered in the human health screening assessment.

Regarding human health, there are limited toxicological data available about PTPTT; however, the available empirical data and information from predictive models are not suggestive of high hazard.

As exposure of the general population in Canada is expected to be negligible, the risk to human health is considered to be low.

Proposed conclusion

Based on the information available, PTPTT does not meet any of the criteria set out in section 64 of CEPA 1999.

The draft Screening Assessment for this substance is available on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances.gc.ca).

Publication of results of investigations and recommendations for a substance — Phenol, (1,1-dimethylethyl)-4-methoxy-, CAS No. 25013-16-5 — paragraphs 68(b) and (c) of the Canadian Environmental Protection Act, 1999

Whereas Phenol, (1,1-dimethylethyl)-4-methoxy- is a substance identified as high priority for action under the Challenge, published in the Canada Gazette, Part I, on December 9, 2006;

Whereas the summary of the draft Screening Assessment conducted on Phenol, (1,1-dimethylethyl)-4-methoxy- pursuant to paragraph 68(b) of the Canadian Environmental Protection Act, 1999 is annexed hereby; and

Whereas it is proposed to conclude that Phenol, (1,1-dimethylethyl)-4-methoxy- does not meet any of the criteria set out in section 64 of the Act,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to take no further action on Phenol, (1,1-dimethylethyl)-4-methoxy- at this time.

Public comment period

Any person may, within 60 days after publication of this notice, file with the Minister of the Environment written comments on the measure the Ministers propose to take and on the scientific considerations on the basis of which the measure is proposed. More information regarding the scientific considerations may be obtained from the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances.gc.ca). All comments must cite the Canada Gazette, Part I, and the date of publication of this notice and be sent to the Executive Director, Program Development and Engagement Division, Gatineau, Quebec K1A 0H3, 819-953-7155 (fax), Existing.Substances.Existantes@ec.gc.ca (email).

ANNEX

Summary of the Screening Assessment on Phenol, (1,1-dimethylethyl)-4-methoxy-

The Ministers of the Environment and of Health have conducted a screening assessment of Phenol, (1,1-dimethylethyl)-4-methoxy- (also known as butylated hydroxyanisole or BHA), Chemical Abstracts Service Registry No. 25013-16-5. The substance BHA was identified in the categorization of the Domestic Substances List as a high priority for action under the Challenge, as it was determined to present intermediate potential for exposure of individuals in Canada and was considered to present a high hazard to human health, based upon classification by other agencies on the basis of carcinogenicity. The substance did not meet the ecological categorization criteria for persistence, bioaccumulation or inherent toxicity to aquatic organisms. Therefore, this assessment focuses principally upon information relevant to the evaluation of risks to human health.

According to information reported under section 71 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), no BHA was manufactured in Canada in 2006 at quantities equal to or greater than the reporting threshold of 100 kg. However, between 100 and 1 000 kg of BHA was imported into Canada, while between 1 000 and 10 000 kg of BHA was used in Canada alone, in a product, in a mixture or in a manufactured item. BHA is permitted for use in Canada as an antioxidant in food. In fats and fat-containing foods, BHA delays the deterioration of flavours and odours and substantially increases the shelf life. It is appropriate for use in foods baked or fried in animal oils because of its high thermal stability and ability to remain active in foods cooked in this manner. BHA is a primary antioxidant used in animal feeds, as it retards the oxidation of vitamins A and E, carotene, xanthophyll pigments, rendered fats and vegetable oils. BHA is a non-medicinal ingredient used as an antioxidant and antimicrobial preservative in final pharmaceutical products, natural health products and veterinary products manufactured in Canada. It is a constituent of personal care products, such as deodorants, shampoos and body lotions, in Canada. BHA is a formulant in pesticide products in Canada. It is a stabilizer or fragrance in rodenticides, insecticides (home garden), fungicides, bactericides (pulp and paper), insecticidal shampoos (cats and dogs), insect repellents (lotion, towelettes) and antibacterial glass and surface cleaners. In Canada, the general population is exposed to BHA through its permitted use as an antioxidant in foods and through its use in personal care products such as shampoos and skin moisturizers.

Based principally on weight-of-evidence-based assessments of international and other national agencies, the critical effect for the characterization of risks to human health from exposure to BHA is carcinogenicity. Lifetime feeding of BHA at high concentrations induced tumours in the forestomach of the rat, mouse and hamster, while no tumours were reported in feeding studies in animals that do not have a forestomach (guinea pig, pig, dog or monkey). It has been postulated that BHA may not be a carcinogen in animals that lack a forestomach. Consideration of the available information regarding genotoxicity indicates that BHA is not likely to be genotoxic. Accordingly, although the mode of induction of tumours is not fully elucidated, the tumours observed are not considered to have resulted from direct interaction with genetic material. Therefore, a threshold approach is used to assess risk to human health.

Based on the comparison of estimated exposures to BHA in Canada with the critical effect levels, and taking into account the uncertainties in the databases on exposure and effects, it is considered that the resulting margins of exposure are adequately protective of human health for non-cancer effects. Margins of exposure for cancer effects are also considered adequate to protect human health. The margins between these levels of exposure and estimates of intake resulting from use of personal care products are considered to be adequately protective of human health.

Based on the available information on its potential to cause harm to human health, it is proposed to conclude that BHA 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.

On the basis of available information, it is proposed to conclude that BHA 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. BHA meets the persistence criteria but does not meet the criteria for bioaccumulation potential as set out in the Persistence and Bioaccumulation Regulations.

Proposed conclusion

Based on the information available, BHA does not meet any of the criteria set out in section 64 of CEPA 1999.

The draft Screening Assessment for this substance is available on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances.gc.ca).

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CANADIAN ENVIRONMENTAL PROTECTION ACT, 1999