Publication of final decision after screening assessment of a substance — Propane, 2-nitro- (2-nitropropane), CAS No. 79-46-9 — specified on the Domestic Substances List (subsection 77(6) 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 final Screening Assessment conducted on 2-nitropropane pursuant to section 74 of the Act is annexed hereby; and

Whereas 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 are releasing a proposed risk management approach document for this substance on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances. gc.ca) to continue discussions with stakeholders on the manner in which the Ministers intend to develop a proposed regulation or instrument respecting preventive or control actions in relation to the substance.

Public comment period on the proposed risk management approach document

Any person may, within 60 days after publication of the proposed risk management approach document, file with the Minister of the Environment written comments on the proposed risk management approach document. More information regarding the proposed risk management approach 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.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Screening Assessment of Propane, 2-nitro- (2-Nitropropane)

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 high priority as it was determined to present an intermediate potential for exposure of individuals in Canada and had been classified by other agencies on the basis of carcinogenicity. Although 2-nitropropane 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 relates primarily to human health risks.

According to information reported in response to a notice under section 71 of CEPA 1999, no companies in Canada reported manufacturing 2-nitropropane in a quantity greater than or equal to the reporting 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 the 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 of exposure 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 exposure scenarios for use of paints and coatings were generated. The exposure of the general population as a result of the 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. An 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 following intraperitoneal injection or inhalation exposures. The substance 2-nitropropane has also demonstrated clear evidence of genotoxicity in the liver of rats, the same organ in which tumours were found. Furthermore, studies have shown that the anionic form of 2-nitropropane, propane 2-nitronate, interacts directly with genetic material in the liver cells of rodents, and the enzymes that activate the metabolism in rodent cells 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 concluded 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 does not meet the criteria for persistence or bioaccumulation 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 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 or that constitute or may constitute a danger to the environment on which life depends.

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.

Conclusion

Based on the information available, it is concluded that Propane, 2-nitro- meets one or more of the criteria set out in section 64 of CEPA 1999.

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

Publication of final decision 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(6) 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 final Screening Assessment conducted on 2-nitrotoluene pursuant to section 74 of the Act is annexed hereby; and

Whereas 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.

Notice is furthermore given that the Ministers of the Environment and of Health are releasing a proposed risk management approach document for this substance on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances. gc.ca) to continue discussions with stakeholders on the manner in which the Ministers intend to develop a proposed regulation or instrument respecting preventive or control actions in relation to the substance.

Public comment period on the proposed risk management approach document

Any person may, within 60 days after publication of the proposed risk management approach document, file with the Minister of the Environment written comments on the proposed risk management approach document. More information regarding the proposed risk management approach 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.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

ANNEX

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

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 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 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 met the ecological categorization criteria for persistence, but did not meet the ecological categorization 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 primarily 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 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 general population is not likely to be exposed to 2-nitrotoluene, since it is used only in industrial applications in Canada. 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 environmental media (air, drinking water and soil) are expected to be negligible. The substance 2-nitrotoluene is not expected to be found in food or beverages. Based on the information obtained on current uses of 2-nitrotoluene in Canada, exposure of 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 of this screening assessment. An increased incidence of tumours was reported in multiple tissues, such as the mesothelial tissues (tunica vaginalis of the testis, epididymis, abdominal wall or surface of abdominal organs), skin (subcutaneous tissues), mammary glands, liver and lungs, in rats exposed via the diet. Tumours in the circulatory system, large intestine and 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, was notably clastogenic in human peripheral lymphocytes and formed 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 exposure were not calculated for non-cancer effects in this assessment since non-cancer effects occurred at a dose at which tumours were observed and because the information available indicates that exposures of the general Canadian population to 2-nitrotoluene from either environmental media or consumer products are 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 concluded 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 and modelling results, 2-nitrotoluene is expected to be persistent in air, water, soil and sediments but is not expected to bioaccumulate. The substance therefore meets 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 no-effect concentrations with estimated realistic worst-case environmental exposure concentrations, it is considered unlikely that 2-nitrotoluene is causing ecological harm in Canada.

Based on the information available, it is concluded 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 or that constitute or may constitute a danger to the environment on which life depends.

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.

Conclusion

Based on the information available, it is concluded that Benzene, 1-methyl-2-nitro- meets one or more of the criteria set out in section 64 of CEPA 1999.

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

Publication of final decision 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(6) 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 final 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 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.

Notice is furthermore given that the Ministers of the Environment and of Health are releasing a proposed risk management approach document for this substance on the Government of Canada’s Chemical Substances Web site (www.chemicalsubstances. gc.ca) to continue discussions with stakeholders on the manner in which the Ministers intend to develop a proposed regulation or instrument respecting preventive or control actions in relation to the substance.

Public comment period on the proposed risk management approach document

Any person may, within 60 days after publication of the proposed risk management approach document, file with the Minister of the Environment written comments on the proposed risk management approach document. More information regarding the proposed risk management approach 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.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

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 of 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 on the 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 PVC and polyurethane foam, 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 reported to be 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 is estimated to end 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%). The substance DTBSBP has a low solubility in water, is moderately volatile and has a tendency to partition to particles and lipids (fat) of organisms because of its hydrophobic nature. The substance 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 persistent in water, soil and sediments. The substance 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. It is therefore concluded 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.

There was no empirical data identified regarding measured concentrations of DTBSBP in environmental media in Canada or elsewhere. The substance DTBSBP may be used in plasticized PVC for food packaging applications. A conservative human 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 by 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 of human life and health. It is therefore concluded that DTBSBP 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.

This substance will be considered for inclusion 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.

Conclusion

Based on the information available, it is concluded that Phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)- meets one or more of the criteria set out in section 64 of CEPA 1999. Phenol, 2,6-bis(1,1-dimethylethyl)-4-(1-methylpropyl)- is persistent and bioaccumulative in accordance with the Persistence and Bioaccumulation Regulations, and its presence in the environment results primarily from human activity.

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

Publication of final decision 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(6) 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 final 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 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.

Notice is furthermore given that the Ministers of the Environment and of Health are releasing a proposed risk management approach document for this substance on the Government of Canada’s Chemical Substances Web site (www. chemicalsubstances.gc.ca) to continue discussions with stakeholders on the manner in which the Ministers intend to develop a proposed regulation or instrument respecting preventive or control actions in relation to the substance.

Public comment period on the proposed risk management approach document

Any person may, within 60 days after publication of the proposed risk management approach document, file with the Minister of the Environment written comments on the proposed risk management approach document. More information regarding the proposed risk management approach 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.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

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 of Methylium, [4-(dimethylamino)phenyl]bis[4-(ethylamino)-3-methylphenyl]-, acetate (MAPBAP acetate), Chemical Abstracts Service Registry No. 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 on the 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 10 000 and 100 000 kg of MAPBAP acetate were imported into Canada in 2006.

Based on reported use patterns and certain assumptions, most of the substance is expected to end up in wastewater, be disposed of in landfills, or be recycled. Based on its physical and chemical properties and partitioning behaviour, MAPBAP acetate could be found in water, sediments and 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 therefore meets the criteria for persistence, but not bioaccumulation potential, as set out in the Persistence and Bioaccumulation Regulations. The conclusion that MAPBAP acetate has low bioaccumulation potential is based on an experimental read-across result, as well as modelled data based on an experimental read-across log K_ow. 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 are expected to occur given the substance’s current use as a paper dye. Concentrations of MAPBAP acetate in surface waters receiving effluents from 10 industrial sites were estimated. These exposure concentrations were found to exceed levels expected to cause harm to sensitive aquatic organisms at all of the sites considered.

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 for 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 toxicity data were identified for MAPBAP acetate. The outputs of quantitative structure-activity relationship predictions for carcinogenicity and genotoxicity were mixed. Information from analogue substances suggests a possible concern for carcinogenicity, genotoxicity and developmental toxicity.

Based upon consideration of the available data on its potential to cause harm to human health, it is concluded that MAPBAP acetate is not a substance 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 upon consideration of the available data on its potential to cause ecological harm (i.e. read-across and modelled data for persistence and aquatic toxicity, and the characterization of risk to aquatic organisms), it is concluded 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.

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.

Conclusion

Based on the information available, it is concluded that Methylium, [4-(dimethylamino)phenyl]bis[4-(ethylamino)3-methylphenyl]-, acetate meets one or more of the criteria set out in section 64 of CEPA 1999. Methylium, [4-(dimethylamino) phenyl]bis[4-(ethylamino)-3-methylphenyl]-, acetate meets the criteria for persistence but does not meet the criteria for bioaccumulation as set out in the Persistence and Bioaccumulation Regulations.

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

Publication of final decision after screening assessment of three 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; and Fatty acids, C _6-19 -branched, zinc salts, CAS No. 68551-44-0 — specified on the Domestic Substances List (subsection 77(6)of the Canadian Environmental Protection Act, 1999)

Whereas substances Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy; 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 the final Screening Assessment conducted on Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy; 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 for the above-noted substances no manufacture or importation activity in a quantity above 100 kg in a calendar year;

Whereas it is concluded that Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy; 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 the above-noted substances,

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; and Fatty acids, C_6-19-branched, zinc salts at this time under section 77 of the Act.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Final Screening Assessment of the Three Substances Listed Below Conducted Under Section 74 of the Canadian Environmental Protection Act, 1999

*CAS RN = Chemical Abstracts Service Registry Number

The above three substances on the Domestic Substances List 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 three substances.

Results from a notice 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 of humans or the environment to these substances in Canada resulting from commercial activity is low. Other sources of entry into the environment have not been identified at this time.

Information received as a result of the above notice 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 three 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 three 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.

While limited data and information on the three substances described above may suggest potential hazardous properties associated with these substances, exposure of the general population in Canada is expected to be low to negligible; therefore, the risk to human health is considered to be low. Confidence in the toxicity database is considered to be low.

Conclusion

Based on available information, it is concluded that Benzene, 1,3,5-tribromo-; Benzene, 1,2,3,4-tetrachloro-5,6-dimethoxy-; 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) of CEPA 1999. 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 be subject to notification and undergo ecological and human health risk assessments. In addition and where relevant, research and monitoring will support verification of assumptions used during the screening assessment.

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

Publication of final decision after screening assessment of a substance — Methane, nitro- (nitromethane), CAS No. 75-52-5 — specified on the Domestic Substances List (subsection 77(6) 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 final Screening Assessment conducted on nitromethane pursuant to section 74 of the Act is annexed hereby; and

Whereas it is concluded 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.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Final Screening Assessment of Methane, nitro- (Nitromethane)

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 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 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 non-traditional 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 the 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 concluded 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 does not meet the criteria for persistence or bioaccumulation 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 concluded 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 or that constitute or may constitute a danger to the environment on which life depends.

This substance will be considered for inclusion 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.

Conclusion

Based on the information available, it is concluded that Methane, nitro- does not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication of final decision after screening assessment of a substance — Glycine, N,N-bis(carboxymethyl)-, CAS No. 139-13-9 — specified on the Domestic Substances List (subsection 77(6) 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 final Screening Assessment conducted on Glycine, N,N-bis(carboxymethyl)- pursuant to section 74 of the Act is annexed hereby; and

Whereas it is concluded 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.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Final 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 No. 139-13-9. This substance was identified in the categorization of the Domestic Substances List as a high priority for action under the Challenge. The substance NTA was identified as a high priority as it was determined to present intermediate potential for exposure of individuals in Canada and had been classified by other agencies on the basis of carcinogenicity. Although it was concluded that 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 serve only as supporting information.

According to information reported in response to a notice published under 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. The substance 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. The substance 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 related to exposure and hazard characterization, it is considered that the resulting margins of exposure are adequately protective of human health.

Based on the available information on its potential to cause harm to human health, it is concluded 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.

An ecological exposure scenario was developed based on the information on commercial use to conservatively estimate releases into the aquatic environment from industrial operations and the 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. In addition, information was identified indicating that NTA is likely to degrade quickly in environmental media.

Based on the information available, it is concluded 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. The substance NTA does not meet the persistence or bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations.

This substance will be considered for inclusion 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.

Conclusion

Based on the information available, it is concluded that Glycine, N,N-bis(carboxymethyl)- does not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication of final decision 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(6) 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 final 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 concluded 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.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Final 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 of 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 on the 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 dialkyldithiophosphate 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 during use. Small proportions are estimated to be released to wastewater (1.9%) and to paved/unpaved land 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 water, soil and sediments. 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 moderately 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 below the predicted aquatic no-effect concentration (PNEC) calculated from a Species Sensitivity Distribution (SSD) using data from other substances within the dialkyldithiophosphate category. Additionally, results from a consumer release scenario, that estimates exposure (PECs) resulting from the down-the-drain release using 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, conservative risk quotients are almost always below 1.

Based on the information available, it is concluded 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 or that constitute or may constitute a danger to the environment on which life depends.

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 its use as a motor oil additive, 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 include dermal irritation, body weight loss, 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 (additive in motor oil) and levels associated with effects in experimental animals are considered to be adequately protective. It is thus concluded that zinc BDBP 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.

This substance will be considered for inclusion 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.

Conclusion

Based on the information available, it is concluded 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 CEPA 1999.

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

Publication of final decision 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(6) 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 final Screening Assessment conducted on benzenepropanoic acid ester pursuant to section 74 of the Act is annexed hereby; and

Whereas it is concluded 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.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Final Screening Assessment of 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)

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 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 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 benzenepropanoic acid ester was not considered to be a high priority for assessment of potential risks to human health, based on the 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 primarily 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, a total of 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 data from selected chemical analogues, benzenepropanoic acid ester is persistent in water, soil and sediment. It has a high modelled log K_ow value of 6.68. However, new modelled bioaccumulation data that take 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.

Therefore, it is concluded that benzenepropanoic acid ester 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.

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).

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. Therefore, it is concluded that benzenepropanoic acid ester 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.

This substance will be considered for inclusion 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.

Conclusion

Based on the information available, it is concluded that 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) does not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication of final decision 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(6) 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 final 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 concluded 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.

JIM PRENTICE
Minister of the Environment
LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Final 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 of 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 Ministerial Challenge because it had been found to meet the ecological categorization criteria for persistence, bioaccumulation potential and inherent toxicity to non-human organisms and was 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 on the 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 principally 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. The substance 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 in the aquatic environment. The BPAF component will be in a neutral form in the aquatic environment at circum-neutral to acidic pH but will dissociate into its anionic form at alkaline pH. Because of this dissociation behaviour, the assessment of PTPTT focuses to a large extent 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 largely remain in the water column with a smaller amount likely 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, PTPTT’s dissociation products 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 PTPTT’s dissociation products 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 concentration (PEC) in water for BTP and BPAF were below predicted no-effect concentrations (PNECs) calculated for sensitive aquatic species. Therefore, based on the information presented in this screening assessment, it is concluded that PTPTT 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.

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. The substance 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 of 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 and therefore these dissociation products were not considered in the human health screening assessment.

There is a limited health effects database available for PTPTT; however, the available empirical data and information from predictive models is 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. On the basis of the carcinogenicity of PTPTT, for which there may be a probability of harm at any level of exposure, and applying a precautionary approach, it is concluded that PTPTT 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.

This substance will be considered for inclusion 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.

Conclusion

Based on the information available, it is concluded 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 CEPA 1999.

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