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Vol. 145, No. 3 — January 15, 2011

DEPARTMENT OF THE ENVIRONMENT

DEPARTMENT OF HEALTH

CANADIAN ENVIRONMENTAL PROTECTION ACT, 1999

Publication of Final Decision after Screening Assessment of Substances — Batch 10

CAS No. 124751-15-1
CAS No. 42739-61-7
CAS No. 7440-48-4
CAS No. 7646-79-9
CAS No. 10124-43-3
CAS No. 10393-49-4
CAS No. 64365-17-9
CAS No. 65997-13-9
CAS No. 68648-53-3
CAS No. 65997-06-0
CAS No. 330-54-1
CAS No. 85702-90-5

Publication of Results of Investigations and Recommendations for a Substance

CAS No. 302-01-2

Publication of results of investigations and recommendations for a substance Hydrazine, CAS No. (see footnote 1) 302-01-2 — specified on the Domestic Substances List (paragraphs 68(b) and (c) of the Canadian Environmental Protection Act, 1999)

Whereas hydrazine 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 Screening Assessment conducted on hydrazine pursuant to paragraphs 68(b) and (c) of the Canadian Environmental Protection Act, 1999 is annexed hereby; and

Whereas it is concluded that hydrazine 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 His Excellency the Governor in Council that hydrazine be added to Schedule 1 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), substances@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.

JOHN BAIRD
Minister of the Environment

LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Screening Assessment of Hydrazine

The Ministers of the Environment and of Health have conducted a screening assessment of hydrazine, Chemical Abstracts Service Registry No. 302-01-2. The substance hydrazine was identified in the categorization of the Domestic Substances List as a high priority for action under the Chemicals Management Plan Challenge initiative. Hydrazine was identified as a high priority as it was considered to pose an intermediate potential for exposure of individuals in Canada and is classified by other agencies on the basis of carcinogenicity. The substance did not meet the ecological categorization criteria for persistence or bioaccumulation potential, but it did meet the criteria for inherent toxicity to aquatic organisms.

Most hydrazine is imported into Canada in aqueous solutions, the form of the product commonly found on the market. In aqueous solutions, all the hydrazine is invariably present as the hydrate. This chemical species has a molecule of water loosely attached to an electronegative nitrogen atom by a weak hydrogen bond. The hydrated form is not considered to be chemically different from the anhydrous substance, and can be considered to represent a mixture of the substance with water. Therefore, this assessment considers that hydrazine and hydrazine hydrate are effectively the same substance. Only minor differences in physical-chemical properties are observed between these two forms due to the association of hydrazine with water in the hydrated form.

According to information submitted under section 71 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), hydrazine was not manufactured by any company in Canada in the calendar year 2006 above the 100 kg reporting threshold. However, 10 000–100 000 kg of hydrazine was reported to have been imported in 2006. The major use of hydrazine is as a corrosion inhibitor in boiler water used at power generating plants. Releases of hydrazine to the environment from these sources do occur. However, exposure of the general population of Canada to hydrazine is expected to be low.

Based principally on the weight-of-evidence-based assessments of international or other national agencies, a critical effect for characterization of risk to human health for hydrazine is carcinogenicity. Increased incidences of bronchial tumours in male and female rats, thyroid tumours in male rats, and nasal tumours in hamsters were observed after inhalation exposure. Increased incidences of lung tumours were observed in mice of both sexes after oral exposure. Genotoxicity was observed in both in vivo and in vitro assays with hydrazine. Based on tumours observed in multiple sites in experimental rodents for which modes of induction have not been fully elucidated, it cannot be precluded that hydrazine induces tumours via a mode of action involving direct interaction with genetic materials.

Repeated-dose studies based on inhalation exposure showed effects on the respiratory systems and systemic effects in multiple sites of male rats. Except for increased mortality, no other effects were observed from repeated-dose studies based on oral exposure to hydrazine. Increased incidence of bile duct proliferations was observed in male rats exposed to hydrazine hydrate. Margins of exposure (MOE) were derived for inhalation and oral exposures and these margins were considered adequate to account for uncertainties in the exposure and health effects dataset for non-cancer effects. However, based on the observed genotoxicity and carcinogenicity, for which there may be a probability of harm at any level of exposure, it is concluded that hydrazine 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.

Hydrazine has high aquatic toxicity but does not meet the criteria defined for persistence or bioaccumulation potential set out in the Persistence and Bioaccumulation Regulations of CEPA 1999. Given its use, particularly in power generating plants, this substance tends to be dispersed widely in the Canadian environment. The National Pollutant Release Inventory reported sustained relatively high quantities of hydrazine released to the environment over a six-year period. In some cases, concentrations in surface water near nuclear and fossil-fuel power generating plants across Canada, estimated based on measured and modelled concentrations in effluent outfalls, are higher than or close to the estimated no-effect levels. Based on this information, it is concluded that hydrazine 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, 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 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 hydrazine meets one or more of the criteria set out in section 64 of the CEPA, 1999.

The Screening Assessment as well as the proposed risk management approach document 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 substanceResin acids and Rosin acids, fumarated, barium salts, CAS No. 124751-15-1 — specified on the Domestic Substances List (subsection 77(6) of the Canadian Environmental Protection Act, 1999)

Whereas Resin acids and Rosin acids, fumarated, barium salts 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 Screening Assessment conducted on the substance 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 the substance above 100 kg per calendar year;

Whereas it is concluded that the substance does 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 this substance,

Notice therefore is hereby given that the Ministers of the Environment and of Health propose to take no further action on Resin acids and Rosin acids, fumarated, barium salts at this time under section 77 of the Act.

JOHN BAIRD
Minister of the Environment

LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Screening Assessment of Resin acids and Rosin acids, fumarated, barium salts

Resin acids and Rosin acids, fumarated, barium salts, Chemical Abstracts Service Registry No. 124751-15-1, a substance on the Domestic Substances List (DSL), was identified as high priority for screening assessment, to be part of the Challenge, because it meets 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 was believed to be in commerce in Canada. However, this substance was 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, it is 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 this substance.

Results from a notice issued under paragraph 71(1)(b) of CEPA 1999 on June 20, 2009, as part of the Challenge, revealed no reports of industrial activity (import or manufacture) with respect to this substance in Canada, above the reporting threshold of 100 kg, for the specified reporting year of 2006. These results suggest that this substance is not in use above the specified reporting threshold, and therefore the likelihood of exposure to this substance in Canada resulting from commercial activity is low. Other sources of entry into the environment have not been identified at this time.

Responses to the above notice and the accompanying questionnaire of June 20, 2009, also revealed no new information relevant to the PBiT properties of this substance. Given the lack of import or manufacture activity above the reporting threshold for this substance, no further collection or analysis relevant to the persistence, bioaccumulation and ecological effects of this substance, beyond what was done for categorization, has been conducted. Therefore, the decisions on PBiT properties made during categorization remain unchanged and accordingly this substance is considered to be highly hazardous to non-human organisms. It is also considered to meet the criteria for both persistence and bioaccumulation as set out in the Persistence and Bioaccumulation Regulations.

As mentioned above, since the results from the notice issued under paragraph 71(1)(b) of CEPA 1999 on June 20, 2009, indicate that this substance is not in use above the specified reporting threshold, the likelihood of exposure to the general population in Canada is considered to be low; hence, the potential risk to human health is considered to be low. Furthermore, this substance was 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, it is not on the European Union’s Candidate List of Substances of Very High Concern for Authorisation.

Conclusion

Based on available information, it is concluded that Resin acids and Rosin acids, fumarated, barium salts do not meet any of the criteria set out in section 64 of CEPA 1999.

Because this substance is listed on the Domestic Substances List, its import and manufacture in Canada is not subject to notification under subsection 81(1). Given the hazardous properties of this substance, there is concern that new activities that have not been identified or assessed could lead to this substance 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 this substance so that new manufacture, import or use of this substance be subject to notification and undergo ecological and human health risk assessments.

The 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 substanceNickel, bis[2,3-bis(hydroxyimino)-N-(2-methoxyphenyl)butanamidato]-,CAS No. 42739-61-7 — specified on the Domestic Substances List (subsection 77(6) of the Canadian Environmental Protection Act, 1999)

Whereas Nickel, bis[2,3-bis(hydroxyimino)-N-(2-methoxyphenyl)butanamidato]- 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 Screening Assessment conducted on the substance 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 the substance above 100 kg per calendar year;

Whereas it is concluded that the substance does 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 this substance,

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

JOHN BAIRD
Minister of the Environment

LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Screening Assessment Report of Nickel,
bis[2,3-bis(hydroxyimino)-N-(2-methoxyphenyl)butanamidato]-

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 Nickel, bis[2,3-bis(hydroxyimino)-N-(2-methoxyphenyl)butanamidato]-, Chemical Abstracts Service Registry No. 42739-61-7. This substance will be referred to by its derived acronym, nickel BHMB, in this assessment. Nickel BHMB was identified as a high priority for screening assessment and included in the Ministerial Challenge initiative under the Chemicals Management Plan 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 nickel BHMB was not initially 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 for categorization of substances on the Domestic Substances List.

Nickel BHMB is an organometallic substance that is currently used in Canada primarily as a nickel alloy component for welding. In the past it was reported to be used in Canada as a colourant, which is consistent with the known use, as a pigment, of a chemically similar substance, Nickel, bis[2,3-bis(hydroxyimino)-N-phenylbutanamidato-N,N (herein referred to as nickel BBHP), Chemical Abstracts Service Registry No. 29204-84-0. The substance is not naturally produced in the environment. It is not reported to be manufactured in Canada or imported into the country, and while it was reported to be used in Canada in 2006, it was at a volume below 1 000 kg.

Based on certain assumptions and reported use patterns in Canada, most of the substance is chemically destroyed (chemically transformed) in the welding process. Some unused portion of the reported total mass in commerce (less than 1 000 kg) may end up in waste disposal sites and a negligible amount may be conservatively estimated to be released to water. Nickel BHMB has a very low modelled solubility, consistent with the low modelled and experimental solubility of its analogue, nickel BBHP in water. Like many substances used as pigments, nickel BHMB is expected to be present in the environment primarily as chemically stable micro-particulate matter that is not volatile, and has a tendency to partition by gravity to sediments if released to surface waters, and to soils if released to air.

Based on its physical and chemical properties, nickel BHMB is expected to be persistent in the environment. No experimental, bioconcentration or bioaccumulation data were available for this organometallic substance. While quantitative structure-activity relationship models for bioconcentration and bioaccumulation were deemed to have high degrees of uncertainty, as nickel BHMB was outside of the model domains of applicability, they were used as a lower weighted line of evidence. The metabolism corrected models showed a low potential for bioaccumulation and bioconcentration (< 5 000 L/kg). Qualitative lines of evidences that were relied upon included the physical and chemical properties of nickel BHMB as well as knowledge of the general qualities of pigment-like substances. Since nickel BHMB, with a high molecular weight, has a very high cross-sectional diameter, it is expected to have limited bioavailability. In addition, the high thermal decomposition and boiling point of nickel BHMB suggest that the substance is relatively inert and is not likely to be highly bioavailable. The weight of evidence (both modelled and qualitative) therefore suggests that this substance does not have significant potential to bioconcentrate or bioacccumulate.

The substance therefore meets the persistence criteria but does not meet the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations of the Canadian Environmental Protection Act, 1999.

For this screening assessment, a very conservative generic exposure scenario was used in which an industrial operation (user of the substance) discharges nickel BHMB into the aquatic environment. A risk quotient analysis, integrating a conservative predicted environmental concentration with a predicted no-effect concentration, indicated that current estimated exposure concentrations of nickel BHMB in water are unlikely to cause ecological harm in Canada. The predicted environmental concentration in water was nearly two orders of magnitude below predicted no-effect concentrations calculated for sensitive aquatic organisms.

Based on the information presented in this final screening assessment, it is concluded that nickel BHMB 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.

No empirical health effects data were identified for nickel BHMB or its analogue, nickel BBHP. The outputs of qualitative structure-activity relationship predictions for nickel BHMB and information on other nickel compounds suggest potential hazardous properties (i.e. mutagenicity, carcinogenicity and skin and respiratory sensitization).

Exposures of the general population to nickel BHMB through environmental media (air, drinking water and soil), including food and beverages, are expected to be negligible. General population exposure to nickel BHMB from use of consumer products is not expected. As exposure of the general population through environmental media in Canada is expected to be negligible, the risk to human health is considered to be low. It is therefore concluded that nickel BHMB 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.

Conclusion

Based on the information available, it is concluded that Nickel, bis[2,3-bis(hydroxyimino)-N-(2-methoxyphenyl)butanamidato]- does not meet any of the criteria set out in section 64 of CEPA 1999.

Because this substance is listed on the Domestic Substances List, its import and manufacture in Canada are not subject to notification under subsection 81(1). Given the potential hazardous properties of this substance, there is concern that new activities that have not been identified or assessed could lead to the substance 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 this substance so that new manufacture, import or use of the substance be subject to notification and undergo ecological and human health risk assessments.

The 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 four substances — Cobalt, CAS No. 7440-48-4; Cobalt chloride, CAS No. 7646-79-9; Sulfuric acid cobalt(2+) salt (1:1), CAS No. 10124-43-3; and Sulfuric acid, cobalt salt, CAS No. 10393-49-4 — specified on the Domestic Substances List (subsection 77(6) of the Canadian Environmental Protection Act, 1999)

Whereas Cobalt, Cobalt chloride, Sulfuric acid cobalt(2+) salt (1:1) and Sulfuric acid, cobalt salt are substances on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

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

Whereas it is concluded that these substances do 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 these substances at this time under section 77 of the Act.

JOHN BAIRD
Minister of the Environment

LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Screening Assessment Report of Cobalt, Cobalt chloride, Sulfuric acid cobalt(2+) salt (1:1) and Sulfuric acid, cobalt salt

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 elemental cobalt, Chemical Abstracts Service Registry Number (CAS No.) 7440-48-4, Cobalt chloride, CAS No. 7646-79-9, and cobalt sulfate, CAS No. 10124-43-3 and CAS No. 10393-49-4. The substances elemental cobalt, Cobalt chloride and cobalt sulfate (CAS No. 10124-43-3) were identified in the categorization of the Domestic Substances List as high priorities for action in the Challenge initiative under the Chemicals Management Plan. Elemental cobalt and cobalt sulfate (CAS No. 10124-43-3) were considered to pose the “greatest potential for exposure” of individuals in Canada whereas Cobalt chloride was considered to pose intermediate potential for exposure. All of these substances are classified by other agencies on the basis of carcinogenicity. These substances all met the ecological categorization criteria for persistence; Cobalt chloride and cobalt sulfate also met the categorization criteria for inherent toxicity to aquatic organisms. Therefore this assessment considers both human health and ecological risks.

The substances were assessed together as they generate a common moiety of concern, Co2+, under physiological and environmental conditions, and are thus considered to be toxicologically equivalent. Additionally, measurements of cobalt in environmental media and foods are not able to distinguish between forms of cobalt. However, this assessment does not consider other cobalt substances, which may also contribute to this moiety. To the extent possible, only releases of cobalt related to the three cobalt substances were considered for the ecological assessment. Other anthropogenic sources of the cobalt moiety to the environment were not systematically included.

In 2006, according to domestic information reported under section 71 of CEPA 1999, between 1 000 000 and 10 000 000 kg of elemental cobalt were manufactured, and between 100 000 and 1 000 000 kg of elemental cobalt were imported and used. In 2006, Canadian companies reported the manufacture of between 100 000 and 1 000 000 kg and the import and use of between 10 000 and 100 000 kg of Cobalt chloride. Additionally in 2006, submissions for cobalt sulfate reported: (1) the manufacture of between 1 000 000 and 10 000 000 kg for CAS No. 10124-43-3 and 64 400 kg for CAS No. 10393-49-4; (2) the import of between 100 000 and 1 000 000 kg (CAS No. 10124-43-3) and 1 449 700 kg (CAS No. 10393-49-4); (3) the use of between 1 000 000 and 10 000 000 kg (CAS No. 10124-43-3) and 1 462 600 kg (CAS No. 10393-49-4). In 2008, in Canada, the majority of cobalt from cobalt-containing commercial substances was recycled (70%) or was disposed (27%). In Canada, elemental cobalt, Cobalt chloride, and cobalt sulfate are primarily used as industrial raw materials; in particular elemental cobalt is commonly used in the production of alloys and carbides with high temperature and wear resistance.

Anthropogenic releases of elemental cobalt, Cobalt chloride and cobalt sulfate to the environment are almost entirely due to various industrial activities including base metal production and alloys/superalloys manufacturing. Following release from these sources, the above cobalt substances may enter the aquatic ecosystem. Elemental cobalt, in the form of powders, has a limited capacity for dissolution in water, whereas cobalt chloride and cobalt sulfate have high water solubility. Therefore these substances will dissolve in contact with moisture once in the aquatic media and will yield a variety of dissolved cobalt species of varying proportions depending on the environmental conditions. Dissolved cobalt has been demonstrated to have a relatively high potential to cause harm to aquatic organisms.

Site-specific exposure scenarios were developed for the major industrial sources of elemental cobalt, Cobalt chloride and cobalt sulfate to the environment. Exposure concentrations were predicted near seven industrial facilities that include five nickel/ copper/cobalt smelters and refineries, one cobalt alloy manufacturer and one manufacturer of a battery component. Based on a risk quotient analysis, there is likelihood of harm to aquatic organisms resulting from exposure to the total cobalt moiety. However, the specific contribution of the three substances to the total exposure to the dissolved cobalt moiety remains uncertain. It is therefore concluded, at this time, that the three substances are not individually 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. Elemental cobalt, Cobalt chloride and cobalt sulfate meet the criteria for persistence but do not meet the criteria for bioaccumulation potential as set out in the Persistence and Bioaccumulation Regulations.

Based on available information on concentrations of total cobalt in environmental media (soil, drinking water, ambient air) and food, as well as results from surveys conducted under section 71 of CEPA 1999, the general population is expected to be exposed primarily to cobalt through diet. The dietary intake of total cobalt by Canadians was found to be similar to that of other developed nations. Adult Canadians are also potentially exposed to cobalt through the use of personal care products reported to contain cobalt chloride.

Based principally on the weight-of-evidence-based assessments of international or other national agencies, a critical effect for characterization of risk to human health for elemental cobalt, Cobalt chloride, and cobalt sulfate is carcinogenicity. Increased incidences of lung tumours were observed in male mice and rats exposed by inhalation to the highest concentration of cobalt sulfate tested, and in female mice and rats at the two highest concentrations of cobalt sulfate tested in a 2-year bioassay. No evidence was available to suggest carcinogenicity via the oral route. In vitro and in vivo genotoxicity data indicate that elemental cobalt, Cobalt choride and cobalt sulfate have the potential to cause DNA and chromosome damage. However, these effects are likely mediated by indirect mechanisms including the generation of reactive oxygen species, increased oxidative stress, and inhibition of DNA repair enzymes. As the tumours observed in experimental animals are unlikely to have resulted from direct interaction with genetic material, a margin of exposure approach is used to assess risk to human health.

The critical effect level for non-cancer effects by the oral route is a conservatively estimated lowest observed adverse effect level of 0.04 mg Co/kg-bw per day based on lethal cardiomyopathy in subjects who consumed large quantities of beer containing cobalt sulfate. The affected population may have been more sensitive due to dietary insufficiencies and prior cardiac damage from excessive alcohol consumption. As cobalt is known to stimulate red blood cell production, cobalt salts have been used in humans to treat anaemia at doses up to 0.32 mg Co/kg-bw per day for periods of several weeks to several months. There is some evidence for reproductive and developmental toxicity of soluble cobalt (II) salts in rodents, but only at dose levels more than 100 times higher than the lowest effect levels in humans.

The critical effect level for non-cancer effects by inhalation is a lowest observed adverse effect concentration of 0.0151 mg Co/m3 in workers exposed to cobalt dust, based on a significantly higher prevalence of eye, nose and throat irritation and cough, and reduced lung function, relative to controls (unexposed workers). These effects were not observed in workers exposed to cobalt dust at 0.0053 mg Co/m3. The critical effect level in humans is 25 times lower than the lowest concentration at which tumours were observed in rodent bioassays.

The margins between upper-bounding estimates of exposure to cobalt from environmental media, food and consumer products and levels associated with effects are considered adequate to address uncertainties in the health effects and exposure databases. On the basis of the adequacy of the margins between conservative estimates of exposure to Cobalt and critical effect levels in humans, it is concluded that Cobalt, Cobalt chloride and cobalt sulfate are 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.

The relative importance of the three substances as contributors to the environmental loading and effects of total dissolved cobalt does however warrant further examination. Consequently, it is proposed that these and other substances contributing to the total loadings of the cobalt moiety in the environment be considered in a future moiety-based assessment.

The three substances 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 Cobalt; Cobalt chloride; Sulfuric acid cobalt(2+) salt (1:1); and Sulfuric acid, cobalt salt do not meet any of the criteria set out in section 64 of the Canadian Environmental Protection Act, 1999.

The 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 substances — Resin acids and Rosin acids, hydrogenated, esters with pentaerythritol, CAS No. 64365-17-9; Resin acids and Rosin acids, hydrogenated, esters with glycerol, CAS No. 65997-13-9; Resin acids and Rosin acids, hydrogenated, esters with triethylene glycol, CAS No. 68648-53-3; and Rosin, hydrogenated, CAS No. 65997-06-0 — specified on the Domestic Substances List (subsection 77(6) of the Canadian Environmental Protection Act, 1999)

Whereas Resin acids and Rosin acids, hydrogenated, esters with pentaerythritol; Resin acids and Rosin acids, hydrogenated, esters with glycerol; Resin acids and Rosin acids, hydrogenated, esters with triethylene glycol; and Rosin, hydrogenated are substances on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

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

Whereas it is concluded that the substances do 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 the substances at this time under section 77 of the Act.

JOHN BAIRD
Minister of the Environment

LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Screening Assessment Report of Resin acids and Rosin acids, hydrogenated, esters with pentaerythritol; Rosin, hydrogenated; Resin acids and Rosin acids, hydrogenated, esters with triethylene glycol; and Resin acids and Rosin acids, hydrogenated, esters with glycerol

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 Rosin, hydrogenated (HR), Chemical Abstracts Service Registry No. 65997-06-0; Resin acids and Rosin acids, hydrogenated, esters with pentaerythritol (HRPE), Chemical Abstracts Service Registry No. 64365-17-9; Resin acids and Rosin acids, hydrogenated, esters with glycerol (HRGE), Chemical Abstracts Service Registry No. 65997-13-9; and Resin acids and Rosin acids, hydrogenated, esters with triethylene glycol (HRTE), Chemical Abstracts Service Registry No. 68648-53-3. These substances will be referred to by their derived acronyms, HR, HRPE, HRGE and HRTE, respectively, in this assessment. These substances were identified as high priorities for screening assessment and were included in the Challenge initiative under the Chemicals Management Plan because they were found to meet the ecological categorization criteria for persistence, bioaccumulation potential and inherent toxicity to non-human organisms and are believed to be in commerce in Canada. The substances HR, HRPE, HRGE and HRTE were 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 for categorization of substances on the Domestic Substances List.

The substances HR, HRPE, HRGE and HRTE are organic UVCBs (Unknown or Variable Composition, Complex Reaction Products or Biological Materials) substances that are used in Canada for various purposes, which may include application in adhesives and sealers, cosmetics, electronics, paints and coatings, and inks and paper. Resin acid components of these substances are present naturally in some plants; however, hydrogenated resin acids and hydrogenated resin acid esters are not known to be naturally produced. These substances are not reported to be manufactured in Canada; however, import volumes in 2006 were 10 000–100 000 kg/year for HR and HRPE, 100 000–1 000 000 kg/year for HRGE, and 1 000–10 000 kg/year for HRTE.

Based on certain assumptions and reported use patterns in Canada, it is expected that the majority of these substances end up at waste disposal sites. Generally, 5% or less is estimated to be released to water based on industrial and consumer/commercial uses, and no releases are predicted to air or soil. The substances HR, HRPE, HRGE and HRTE are reported to have low experimental solubilities in water. However, HR solubility may depend on pH with higher solubility found at a higher pH. The substances HR, HRPE, HRGE and HRTE are expected to partition to sediments when released in water. However a significant fraction of HR may still remain in the water column.

Based on their physical and chemical properties, experimental biodegradation data for HR, HRPE and HRGE, analogue biodegradation data for HRTE and predicted data for all four substances, HR, HRPE, HRGE and HRTE are expected to be persistent in the environment. New experimental data relating to bioconcentration of components of HR along with predicted bioaccumulation potential of additional components suggest that HR has a low potential to accumulate in the lipid tissues of organisms. The lower molecular weight components of HRPE, HRGE and HRTE do not show a high predicted bioaccumulation potential based on multiple model results, suggesting that metabolism will mitigate bioaccumulation potential. It has been predicted that the larger, higher molecular weight components would have limited bioavailability, such that significant bioaccumulation would not be expected. Based on the available information, HR, HRPE, HRGE and HRTE do not have the potential to bioaccumulate in the environment.

Experimental toxicity data for a chemical analogue UVCB substance of HRPE and HRGE suggest that saturated solutions of the substance do not cause acute harm to aquatic organisms, including fish, daphnids and algae test species.

Experimental toxicity data for a chemical analogue UVCB substance of HR indicated that saturated solutions of the substance do not cause acute harm to test fish and algae species. However, effects were seen at the highest concentration tested for daphnids. Thus, component-based toxicity was used to determine a conservative predicted no-effect concentration (PNEC) for HR. For HR, a conservative exposure scenario was applied in which two major industrial operations discharge HR into the aquatic environment. The predicted environmental concentration (PEC) in water was many orders of magnitude below the PNECs calculated for HR. As no suitable chemical analogue was found for HRTE, predicted component-based toxicity values were used to determine a conservative PNEC value. A conservative exposure scenario was selected in which an industrial operation discharges HRTE into the aquatic environment. The PEC in water was, similarly, many orders of magnitude below the conservative PNECs calculated for HRTE.

No empirical data were identified for concentrations of these compounds in environmental media. The potential for exposure of the general population to HR, HRPE, HRGE and HRTE from environmental media is expected to be low. In addition, there is potential for low levels of exposure from the use of a limited number of consumer products which may include lipstick, mascara, hair styling and hair removal products and consumer adhesives. Based on the physical-chemical properties of the substances, inhalation exposure is not expected from these products; however, there is potential for low levels of dermal or oral (lipstick) exposure. The health effects database for HR, HRPE, HRGE and HRTE is limited. Chronic studies for HR and selected analogues indicated no evidence of carcinogenicity in experimental animals and the available data does not indicate genotoxic potential. Positive skin sensitization reactions appear to be associated with consumer products containing concentrations of ≥ 20% HRGE or HRPE, and possibly HRTE. However, there is evidence to indicate that HR may be a possible skin sensitizer at lower concentrations. Consumer use of products containing these substances is expected to be low.

The margins between upper-bounding estimates of exposure via environmental media or consumer products for HR, HRPE, HRGE or HRTE and the oral critical effect levels observed in studies with one or more of these compounds or related analogues are considered adequate to address uncertainties in the health effects and exposure databases.

Based on comparison of the upper-bounding estimates of exposure via environmental media or consumer products for HR, HRPE, HRGE or HRTE with the oral critical effect levels observed in studies with one or more of these compounds or related analogues, a concern for human health was not identified.

Based on the information available, it is concluded that HR, HRPE, HRGE and HRTE are not entering the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity, or that constitute or may constitute a danger to the environment on which life depends.

Based on the information available, it is concluded that HR, HRPE, HRGE and HRTE are not entering the environment in a quantity or concentration or under conditions that constitute a danger in Canada to human life or health.

The substances HR, HRPE, HRGE and HRTE do meet the persistence criteria but do not meet the bioaccumulation criterion as set out in the Persistence and Bioaccumulation Regulations of the Canadian Environmental Protection Act, 1999.

These substances 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 Resin acids and Rosin acids, hydrogenated, esters with pentaerythritol; Rosin, hydrogenated; Resin acids and Rosin acids, hydrogenated, esters with triethylene glycol; and Resin acids and Rosin acids, hydrogenated, esters with glycerol do not meet any of the criteria set out in section 64 of the CEPA 1999.

The 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 substanceUrea, N′-(3,4-dichlorophenyl)-N,N-dimethyl-, CAS No. 330-54-1 — specified on the Domestic Substances List (subsection 77(6) of the Canadian Environmental Protection Act, 1999)

Whereas Urea, N′-(3,4-dichlorophenyl)-N,N-dimethyl- 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 Screening Assessment conducted on the substance pursuant to section 74 of the Act is annexed hereby; and

Whereas it is concluded that the substance 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 the substance at this time under section 77 of the Act.

JOHN BAIRD
Minister of the Environment

LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Screening Assessment Report of Urea, N′-(3,4-dichlorophenyl)-N,N-dimethyl-

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 Urea, N′-(3,4-dichlorophenyl)-N,N-dimethyl- (diuron), Chemical Abstracts Service Registry No. 330-54-1. This substance will be referred to by its common name, diuron, in this screening assessment. Diuron was identified in the categorization of the Domestic Substances List as a high priority for action in the Challenge initiative under the Chemicals Management Plan. Diuron was identified as a high priority as it was considered to pose an intermediate potential for exposure of individuals in Canada and is classified by other agencies on the basis of carcinogenicity. The substance met the ecological categorization criteria for persistence and for inherent toxicity to aquatic organisms.

Diuron is an organic substance and, according to information submitted under section 71 of CEPA 1999, it was imported into Canada for pesticidal and non-pesticidal uses above the reporting threshold of 100 kg in 2006.

Diuron is a registered active ingredient in pest control products and these uses are regulated by Health Canada’s Pest Management Regulatory Agency (PMRA) under the Pest Control Products Act (PCPA). In 2007, Health Canada’s PMRA re-evaluated pesticidal uses of diuron under Re-evaluation Program 1 and concluded that it is acceptable for continued registration. Information from the re-evaluation of pesticidal uses of diuron was taken into consideration in the current assessment of non-pesticidal uses under CEPA 1999.

This screening assessment considers the potential effects of diuron on human health and the environment as a result of non-pesticidal uses of the substance. Diuron was imported in non-pesticidal products, which were considered industrial in nature, including a hardening agent in epoxy resins and a curing agent in epoxy adhesives for bonding of metal parts. Exposure to the general population from non-pesticidal, industrial uses of diuron is considered to be negligible.

As diuron was classified on the basis of carcinogenicity by other national and international agencies, carcinogenicity was a key focus for the human health portion of this screening assessment. Exposure to diuron, via the diet, increased the incidence of urinary bladder carcinomas in both male and female Wistar rats, while mammary gland adenocarcinomas were noted in NMRI mice. The increases in tumour incidences were noted at high dose levels, which approached maximally tolerated doses. Results of genotoxicity testing, performed both in vitro and in vivo, were predominantly negative. Consideration of the available information regarding genotoxicity, and assessments of other agencies, indicate that diuron 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.

Consistent non-neoplastic effects were observed in rat, mouse and dog. These included erythrocyte damage with compensatory haematopoiesis. Urinary bladder wall thickening and swelling, together with epithelial focal hyperplasia, were observed in the high-dose groups in rat and mouse bioassays.

As general population exposure to diuron as a result of non-pesticidal, industrial uses is considered to be negligible, it is concluded that diuron is a substance that 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.

The ecological components of this assessment build upon the assessment work conducted by Environment Canada following the categorization of substances under CEPA 1999 and also include applicable information from the U.S. EPA’s and PMRA’s assessments (i.e. Re-registration Eligibility Decision for Diuron, dated 2003, and Re-evaluation Decision Diuron, dated 2007). In addition, other information from the European Commission Joint Research Centre and recent scientific literature available in the public domain were considered. Finally, discussion of major metabolites of diuron, and in particular 3,4-dichloroaniline, is provided to assist in understanding the overall environmental impacts of the substance.

Although diuron is expected to be persistent in water and aerobic soil and sediment, it has a low potential to bioaccumulate. Diuron also exhibits relatively high potential for toxicity to sensitive aquatic organisms. A risk quotient analysis, integrating a conservative predicted environmental concentration with a predicted no-effect concentration, indicated that the current estimated exposure concentrations of diuron in water are unlikely to cause ecological harm in Canada. Due mainly to the estimated low releases of this substance to water as a result of current non-pesticidal uses, it is concluded that diuron 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 upon which life depends. Diuron meets the criteria for persistence, but does not meet criteria for bioaccumulation 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 Urea, N′-(3,4-dichlorophenyl)-N,N-dimethyl- does not meet any of the criteria set out in section 64 of the CEPA 1999.

The 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 — 2,9,11,13-Tetraazanonadecanethioic acid, 19-isocyanato-11-(6-isocyanatohexyl)-10,12-dioxo-, S-[3-(trimethoxysilyl)propyl] ester, CAS No. 85702-90-5 — specified on the Domestic Substances List (subsection 77(6) of the Canadian Environmental Protection Act, 1999)

Whereas 2,9,11,13-Tetraazanonadecanethioic acid, 19-isocyanato-11-(6-isocyanatohexyl)-10,12-dioxo-, S-[3-(trimethoxysilyl)propyl] 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 Screening Assessment conducted on the substance pursuant to section 74 of the Act is annexed hereby; and

Whereas it is concluded that the substance 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 the substance at this time under section 77 of the Act.

JOHN BAIRD
Minister of the Environment

LEONA AGLUKKAQ
Minister of Health

ANNEX

Summary of the Screening Assessment Report of 2,9,11,13-Tetraazanonadecanethioic acid, 19-isocyanato11-(6-isocyanatohexyl)-10,12-dioxo-, S-[3-(trimethoxysilyl)propyl] 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 2,9,11,13-Tetraazanonadecanethioic acid, 19-isocyanato-11-(6-isocyanatohexyl)-10,12-dioxo-, S-[3-(trimethoxysilyl)propyl] ester, Chemical Abstracts Service Registry No. (CAS RN) 85702-90-5. In this assessment, this chemical will be referred to by its derived acronym, TIDTE. This substance was identified as a high priority for screening assessment and included in the Challenge initiative under the Chemicals Management Plan 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 TIDTE 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 for categorization of substances on the Domestic Substances List.

The substance TIDTE is an organic substance not naturally produced in the environment, nor is it reported to be manufactured in Canada. In each of 2005 and 2006, there were between 100 and 1 000 kg of this substance imported into the country in products.

Based on the reported use as a component in marine adhesive and sealant products, TIDTE is expected to cross-link to polymers in the formulation. Thus, the majority of TIDTE (99%) is considered to undergo chemical transformation in the formulated product matrix, making it unavailable for release to the environment. Residue of adhesive and sealant in product containers is assumed to be disposed of in landfill sites.

The substance TIDTE is unlikely to be released to the environment in more than very low quantities. Any of the substance that is released to the environment is anticipated to hydrolyze rapidly in water (forming amines, silanol, and methanol), as well as in the presence of moisture in other environmental media. Thus, although ultimate degradation (the metric used for categorization) is expected to be slow (e.g. the silanol — one of the hydrolysis products — is expected to degrade very slowly in the environment), TIDTE undergoes rapid primary degradation.

New model predictions of bioaccumulation that take account of potential for metabolic transformation show that neither TIDTE nor its hydrolysis products are bioaccumulative in aquatic organisms. Therefore, it is concluded that the substance does not meet the persistence or bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations of the Canadian Environmental Protection Act, 1999.

In addition, based on the modelled toxicity data, neither TIDTE nor its hydrolysis products are likely to have high potential to harm aquatic organisms. Considering this, and in view of the low likelihood of release of TIDTE to any environmental compartment, it is concluded that TIDTE 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 constitutes or may constitute a danger to the environment on which life depends.

The potential for exposure of the general population to TIDTE from environmental media is expected to be negligible. Exposure of the general population to TIDTE in consumer products is expected to be low.

There were no empirical health effects data identified for TIDTE or its analogues. Based principally on the low solubility and high reactive nature of TIDTE, quantitative structure-activity relationship (QSAR) predictions, as well as a European Commission classification, the primary hazard concern for TIDTE is skin and respiratory tract sensitization. However, as exposure of the general population to TIDTE is expected to be low to negligible, the risk to human health is expected to be low. It is concluded that TIDTE 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 2,9,11,13-Tetraazanonadecanethioic acid, 19-isocyanato-11-(6-isocyanatohexyl)-10,12-dioxo-, S-[3-(trimethoxysilyl)propyl] ester does not meet any of the criteria set out in section 64 of the Canadian Environmental Protection Act, 1999.

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

Footnote 1
The Chemical Abstracts Service Registry Number (CAS RN) is the property of the American Chemical Society and any use or redistribution, except as required in supporting regulatory requirements and/or for reports to the government when the information and the reports are required by law or administrative policy, is not permitted without the prior, written permission of the American Chemical Society.