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Vol. 145, No. 2 — January 8, 2011

DEPARTMENT OF THE ENVIRONMENT

DEPARTMENT OF HEALTH

Publication after Screening Assessment of Substances — Batch 12

CAS No. 107-51-7

CAS No. 102-06-7

CAS No. 14464-46-1

CAS No. 14808-60-7

CAS No. 3555-47-3

CAS No. 59709-38-5

CAS No. 68937-51-9

CAS No. 1333-86-4

CAS No. 68391-11-7

CAS No. 116-66-5

CAS No. 68583-58-4

CAS No. 101200-53-7

Publication after screening assessment of a substance — Trisiloxane, octamethyl-, CAS No. 107-51-7 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

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

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

Whereas it is proposed to conclude that the substance 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 His Excellency the Governor in Council that the substance be added to Schedule 1 of the Act.

Notice therefore is further given that the Ministers of the Environment and of Health propose the implementation of virtual elimination of the substance under subsection 65(3) of the Act.

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

Public comment period

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

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

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

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

ANNEX

Summary of the Screening Assessment Report of Trisiloxane, octamethyl-

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 Trisiloxane, octamethyl-, Chemical Abstracts Service Registry No. 107-51-7. This substance will be referred to by its derived acronym, MDM, in the assessment. The substance MDM was identified as a high priority for screening assessment and included in the Challenge initiative under the Chemicals Management Plan 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 MDM was not considered to be a high priority for assessment of potential risks to human health, based upon application of the exposure and hazard tools developed by Health Canada for categorization of substances on the Domestic Substances List.

The substance MDM is an organic substance primarily used as an ingredient in industrial, medical and consumer products such as cleaning and degreasing products, lubricants, diluents and solvents, personal care products and cosmetics. The substance does not occur naturally in the environment. The substance MDM is not manufactured in Canada; however, imports for the calendar years 2005 and 2006 were in the range of 100 to 100 000 kg and 10 000 to 100 000 kg, respectively.

Based on certain assumptions and reported use patterns in Canada, most MDM is expected to be exported in end-use products or emitted to air during industrial or consumer and commercial applications. Significant recycling of the substance during industrial use is also expected, with proportionally smaller losses to wastewater or disposal to landfill and incineration sites.

Based on empirical and modelled data, MDM meets persistence criteria in air and sediment but does not meet the criteria for water and soil as set out in the Persistence and Bioaccumulation Regulations. Empirical and modelled bioconcentration factors in excess of 5 000 indicate that MDM also meets the criterion for bioaccumulation potential as set out in the Persistence and Bioaccumulation Regulations.

The available toxicity data indicate that MDM is unlikely to be hazardous to pelagic organisms at or near the limit of water solubility, although there is evidence for adverse effects in some sediment species.

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

Therefore, based on the information available, it is proposed to conclude that MDM is entering or may enter the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity.

In terms of human health, the predominant source of exposure to MDM through environmental media is likely to be via indoor air. Exposure of the general population to MDM from consumer products may occur primarily through the use of cosmetics, including some personal care products.

Limited empirical health effects data were available for MDM. Effects on the liver, kidney and lung, as well as reduced body weight gain were observed in rats following repeated-dose exposure to MDM and its analogues. The margins between the upper-bounding estimates of exposure from environmental media and use of consumer products containing MDM and critical effect levels in experimental animals are considered adequate to address uncertainties in the health effects and exposure databases.

On the basis of the adequacy of the margins between upper-bounding estimates of exposure to MDM and critical effect levels in experimental animals, it is proposed to conclude that MDM 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. Based on available information for human health considerations, it is proposed that MDM does not 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.

Proposed conclusion

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

In addition, it is proposed to conclude that Trisiloxane, octamethyl- meets the criteria for persistence and bioaccumulation potential as set out in the Persistence and Bioaccumulation Regulations, and its presence in the environment results primarily from human activity.

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

Publication after screening assessment of a substanceGuanidine, N,N′-diphenyl-,CAS No. 102-06-7 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

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

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

Whereas it is proposed to conclude 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.

Public comment period

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

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

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

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

ANNEX

Summary of the Screening Assessment Report of Guanidine, N,N′-diphenyl-

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 Guanidine, N,N′-diphenyl-, commonly referred to as diphenylguanidine or DPG, Chemical Abstracts Service Registry No. 102-06-7. This substance was identified as a high priority for screening assessment and included in the Challenge initiative under the Chemicals Management Plan because it was considered to pose an intermediate potential for exposure of individuals in Canada and had been classified by other agencies on the basis of reproductive toxicity. This substance met the ecological criteria for persistence, but not for bioaccumulation potential and inherent toxicity to aquatic organisms.

According to information reported under section 71 of CEPA 1999, 100 000–1 000 000 kg of DPG were imported into Canada in 2006 and 100 000–1 000 000 kg of DPG were used. No companies reported manufacturing DPG in 2006; less than 100 kg of DPG were reported to be released to air, and similarly, less than 100 kg of the substance were reported to be released to water in Canada in 2006. The substance DPG is primarily used as an accelerator to achieve shorter curing times during the vulcanization process in the manufacture of rubber for tires and industrial applications. According to data submitted under section 71 of CEPA 1999, DPG is used in the manufacture of rubber tires, rubber mixtures, industrial rubber sheets, and sealants for automotive and navy applications in Canada.

Based on the available information, exposure to DPG amongst the general population in Canada through environmental media (except soil) is considered to be negligible. Exposure to DPG from dietary sources is not expected. According to the information available and industry data reported under section 71 of CEPA 1999, DPG is used in Canada to manufacture rubber material for tires and industrial applications. Exposure to DPG via soil containing tire debris was estimated and found to be low. Exposure of the general population from consumer products is not expected.

The critical health effect associated with exposure to DPG is reproductive toxicity, based on the observations in experimental animals and the weight-of-evidence-based classification by international agencies.

The margin between upper bound estimates of exposure of the general population to DPG via contact with soil containing tire debris and the lowest effect level in experimental animals is considered adequate to address uncertainties in the health effects and exposure databases.

Based on the information available, it is proposed to conclude that DPG 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 substance DPG meets the criteria for persistence, but not for bioaccumulation potential, as set out in the Persistence and Bioaccumulation Regulations. It is expected to have a moderate potential for toxicity to aquatic organisms, with highest potential for toxicity to certain species of algae. A risk quotient analysis, integrating conservative estimates of exposure with toxicity information, was performed for the aquatic medium to determine whether there is potential for ecological harm in Canada. The risk quotient indicated that in that scenario the current estimated site-specific industrial exposure concentrations of DPG in water are unlikely to cause ecological harm to aquatic organisms. Based on this information and comparison of the expected concentrations in water with a predicted no effect concentration, it is proposed to conclude that DPG is not entering the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity.

This substance will be 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.

Proposed conclusion

Based on the information available, it is proposed to conclude that Guanidine, N,N′-diphenyl- does not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication after screening assessment of two substances — Cristobalite, CAS No. 14464-46-1, and Quartz (SiO 2 ), CAS No. 14808-60-7 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas cristobalite and quartz are substances on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

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

Whereas it is proposed to conclude 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.

Public comment period

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

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

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

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

ANNEX

Summary of the Screening Assessment Report of Cristobalite and Quartz

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 quartz, Chemical Abstracts Service Registry No. 14808-60-7 and cristobalite, Chemical Abstracts Service Registry No. 14464-46-1. These substances were identified in the categorization of the Domestic Substances List as a high priority for action as part of the Challenge initiative under the Chemicals Management Plan. Quartz and cristobalite were identified as high priorities as they were considered to pose greatest potential for exposure of individuals in Canada and their respirable forms are classified by the International Agency for Research on Cancer as carcinogenic to humans (quartz and cristobalite) and by the National Toxicology Program as known human carcinogens (crystalline silica). These substances did not meet the ecological categorization criteria for bioaccumulation potential or inherent toxicity to aquatic organisms.

According to information reported under section 71 of CEPA 1999 for the year 2006, over 10 000 000 kg of quartz were manufactured, imported and used. Based on the results of the same survey, over 10 000 000 kg of cristobalite were manufactured, and between 1 000 000 and 10 000 000 kg were imported and used in the year 2006.

It should be noted that this quantity does not represent the total quantities of quartz and cristobalite in the market in Canada, because response to the mandatory section 71 Survey Notice was required only if the substance or product, mixture or manufactured item containing the substance was composed of more than 5% respirable crystalline silica and was intended for use within a residence. The major uses of quartz and cristobalite are in construction-related activities such as road building and sanding in winter and as cement additives; other uses include the manufacture of glass fibres and ceramics, as fillers and extenders in rubber and coatings, and as abrasives.

Quartz and cristobalite are both naturally occurring. Quartz is found abundantly in many types of rock formations, while cristobalite can be produced in the ashes of volcanic eruptions. Cristobalite is less prevalent than quartz, as its presence is limited to specific geographic regions and mineral types.

Quartz and cristobalite were qualitatively found to be very persistent because they are extremely resistant to chemical weathering. Also, quartz and cristobalite were qualitatively found to not bioaccumulate, since they are expected to have very limited potential for uptake through the gill or gut of aquatic organisms. Respirable fractions may physically accumulate in the lung tissues of terrestrial organisms. In mammals, these crystalline phases can cause lung silicosis and lead to death depending on the severity and duration of exposure. However, detailed risk characterizations at eight Canadian sites indicate that quartz and cristobalite 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.

Quartz and cristobalite meet the criteria for persistence, but do not meet the criteria for bioaccumulation, as set out in the Persistence and Bioaccumulation Regulations. A risk quotient analysis, integrating moderately to highly conservative estimates of exposure with a predicted no-effect concentration resulted in a risk quotient indicating the current estimated exposure concentrations of quartz and cristobalite in air are unlikely to cause harm to terrestrial fauna. On the basis of ecological hazard and estimated releases of quartz and cristobalite it is proposed that the substances 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.

Concentrations of silicon in respirable particulate matter in Canada were identified and used to estimate inhalation exposure to quartz and cristobalite. The major anthropogenic releases of airborne respirable quartz and cristobalite are expected to come from dust generated due to agriculture, construction activity and driving on unpaved and paved roads.

The International Agency for Research on Cancer (IARC) has classified respirable quartz and cristobalite from occupational exposure as Group 1 carcinogens (“carcinogenic to humans”). The U.S. National Toxicology Program classified crystalline silica of respirable size as “known to be a human carcinogen.” The basis for these classifications is sufficient evidence from human studies indicating a causal relationship between exposure to respirable crystalline silica in the workplace and increased lung cancer rates in workers. While the mode of induction of lung tumours is not fully elucidated, sufficient data exists to demonstrate that a threshold approach to risk characterization is appropriate.

On the basis of the adequacy of the margins between conservative estimates of exposure to quartz and cristobalite from ambient air and critical effect levels in experimental animals and humans, it is proposed that quartz and cristobalite 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.

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.

Proposed conclusion

Based on the information available, it is proposed to conclude that cristobalite and quartz do not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication after screening assessment of a substance Trisiloxane, 1,1,1,5,5,5-hexamethyl-3,3-bis[(trimethylsilyl)oxy]-, CAS No. 3555-47-3 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Trisiloxane, 1,1,1,5,5,5-hexamethyl-3,3-bis [(trimethylsilyl)oxy]- is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

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

Whereas it is proposed to conclude 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.

Public comment period

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

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

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

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

ANNEX

Summary of the Screening Assessment Report of Trisiloxane, 1,1,1,5,5,5-hexamethyl-3,3-bis[(trimethylsilyl)oxy]-

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 Trisiloxane, 1,1,1,5,5,5-hexamethyl-3,3-bis[(trimethylsilyl)oxy]-, Chemical Abstracts Service Registry No. 3555-47-3. This substance will be referred to by its derived acronym, M4Q, in the assessment. The substance M4Q was identified as a high priority for screening assessment and included in the Challenge initiative under the Chemicals Management Plan 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 M4Q was not considered to be a high priority for assessment of potential risks to human health, based upon application of the simple exposure and hazard tools developed by Health Canada for categorization of substances on the Domestic Substances List.

The substance M4Q is an organic substance that occurs primarily as a reaction by-product or impurity in a wide range of silicon-based products, including those found in adhesives, sealants, processing intermediates, lubricants, antifoaming agents, paints and coatings. The substance does not occur naturally in the environment. Surveys conducted under section 71 of CEPA 1999 determined that, in 2005 and 2006, M4Q was not manufactured in Canada in quantities equal to or greater than 100 kg. Imports of the substance into Canada were in the range of 1 001–100 000 kg for 2005 and 1 000–10 000 kg for 2006. In all instances of import, the substance was reported to be present as an impurity in an end-use product.

Based on certain assumptions and reported use patterns in Canada, most M4Q is expected to be directed to waste disposal and incineration sites, with smaller proportions being released to water or emitted to air. When released into the environment, M4Q is predicted to reside mainly in air, soil and sediment.

The substance M4Q is predicted to be persistent in air, water, soil and sediment. The substance may also be subject to atmospheric transport, allowing it to reach areas some distance from its emission source. Despite the ability for long-range travel in the atmosphere, results from environmental modelling predict that M4Q lacks the potential to be deposited to water or soil in remote regions and the substance is therefore considered to have low Arctic contamination potential. No monitoring data are available to indicate the occurrence of M4Q in the environment.

While initially categorized as potentially bioaccumulative, new empirical data suggest M4Q has low potential to accumulate in organisms. Therefore, M4Q meets the persistence criteria but does not meet the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations.

Based on the available empirical and modelled data, it is considered unlikely that M4Q will cause adverse effects in aquatic organisms at or near the limit of water solubility.

A risk quotient analysis, integrating a conservative predicted environmental concentration with a predicted no-effect concentration resulted in a risk quotient indicating that current estimated exposure concentrations of M4Q in water are unlikely to cause ecological harm at the current and foreseeable level of use in Canada.

Therefore, it is proposed to conclude that M4Q 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 to M4Q is expected to occur mainly through use of paints, coatings, and cosmetics, including some personal care products.

Limited empirical health effects data were available for M4Q. Health effects data for analogues indicate potential effects mainly on the liver in experimental animals following repeated-dose exposure. The margins between upper-bound estimates of exposure from environmental media (predominantly air) and from use of consumer products containing M4Q (cosmetics and alkyd coating) and critical effect levels in experimental animals are considered adequate to address uncertainties in the health effects and exposure databases.

On the basis of the adequacy of the margins between upper-bound estimates of exposure to M4Q and critical effect levels in experimental animals, it is proposed to conclude that M4Q 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.

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.

Proposed conclusion

Based on the information available, it is proposed to conclude that Trisiloxane, 1,1,1,5,5,5-hexamethyl-3,3-bis[(trimethylsilyl) oxy]- does not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication after screening assessment of a substanceß-Alanine, N-[4-[(2-bromo-6-chloro-4-nitrophenyl)azo]phenyl]-N-(3-methoxy-3-oxopropyl)-, methyl ester, CAS No. 59709-38-5 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas ß-Alanine, N-[4-[(2-bromo-6-chloro-4-nitrophenyl) azo]phenyl]-N-(3-methoxy-3-oxopropyl)-, methyl ester is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

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

Whereas it is proposed to conclude 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.

Public comment period

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

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

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

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

ANNEX

Summary of the Screening Assessment of ß-Alanine, N-[4-[(2-bromo-6-chloro-4-nitrophenyl)azo]phenyl]-N(3-methoxy-3-oxopropyl)-, methyl ester

Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment on β-Alanine, N-[4-[(2-bromo-6-chloro-4-nitrophenyl)azo]phenyl]-N-(3-methoxy-3-oxopropyl)-, methyl ester, Chemical Abstracts Service Registry No. 59709-38-5; this substance will be referred to by its derived acronym, ANMOM, in the assessment. ANMOM 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 was believed to be in commerce in Canada.

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

The substance β-Alanine, N-[4-[(2-bromo-6-chloro-4-nitrophenyl)azo] phenyl]-N-(3-methoxy-3-oxopropyl)-, methyl ester is an organic substance. In 2005, this substance was reported to be imported between 1 001 and 100 000 kg into Canada primarily as a disperse dye in the finishing of textiles, fabrics and apparel. The substance is not naturally occurring in the environment. It is not reported to be manufactured, used or imported into Canada for the 2006 reporting year.

Based on certain assumptions and reported use patterns in Canada, most of the substance ends up in wastewater effluent. ANMOM presents low experimental solubilities in n-octanol (1 670 mg/L) and low predicted solubilities in water for the chemical analogues (ranges between 0.000938 and 0.07 mg/L). ANMOM is predicted to exist primarily as micro-particulate matter that is not volatile, is chemically stable under most conditions 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, this substance is expected to be persistent in the environment. However, experimental data relating to its bioaccumulation in fish and its solubility in octanol and water suggest that this disperse dye has a low potential to accumulate in the lipid tissues of organisms. ANMOM therefore meets the persistence criteria but does not meet the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations. In addition, experimental toxicity data for the chemical analogues, as well as toxicity predictions that take into account revised estimates of bioaccumulation potential, suggest that saturated solutions of the substance do not cause acute harm to aquatic organisms.

For this screening assessment, a very conservative exposure scenario was selected in which an industrial operation (user of the disperse dye) discharges ANMOM into the aquatic environment. The predicted environmental concentration in water was below the predicted no-effect concentrations calculated for fish, daphnids and algae. Based on the information available, it is proposed that ANMOM is not entering the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity.

The potential for exposure of the general population in Canada to this substance from environmental media is expected to be low. Exposure to this substance from its potential use as a dye in textiles and fabrics is also expected to be low.

The limited empirical health effects data identified for this substance, its potential metabolites, and analogues, together with mixed quantitative structure-activity relationship predictions, suggest this substance may pose a potential hazard to human health. However, exposure for the general population of Canada to this substance is expected to be low, and consequently, the potential risk to human health is considered to be low at current potential levels of exposure. It is proposed to conclude that ANMOM does not 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.

Proposed conclusion

Based on the information available, it is proposed to conclude that ß-Alanine, N-[4-[(2-bromo-6-chloro-4-nitrophenyl)azo] phenyl]-N-(3-methoxy-3-oxopropyl)-, methyl ester does not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication after screening assessment of a substance — Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, reaction products with ammonia, octamethylcyclotetrasiloxane and silica, CAS No. 68937-51-9 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, reaction products with ammonia, octamethylcyclotetrasiloxane and silica is a substance on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

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

Whereas it is proposed to conclude 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.

Public comment period

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

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

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

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

ANNEX

Summary of the Screening Assessment Report of Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, reaction products with ammonia, octamethylcyclotetrasiloxane and silica

Pursuant to section 74 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), the Ministers of the Environment and of Health have conducted a screening assessment on Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, reaction products with ammonia, octamethylcyclotetrasiloxane and silica, Chemical Abstracts Service Registry No. (CAS No.) 68937-51-9. This substance will be referred to by its derived acronym, OMSSA, in the screening assessment. This substance was identified as a high priority for screening assessment and included in the Challenge initiative under the Chemicals Management Plan 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 OMSSA was not considered to be a high priority for assessment of potential risks to human health, based upon application of the simple exposure and hazard tools developed by Health Canada for categorization of substances on the Domestic Substances List.

OMSSA belongs to a class of chemicals described as Unknown or Variable Composition, Complex Reaction Products, or Biological Materials (UVCBs). This substance consists of the reaction products of 1,1,1-Trimethyl-N-(trimethylsilyl)-silanamine (HMDS) [CAS No. 999-97-3], Octamethylcyclotetrasiloxane (D4) [CAS No. 556-67-2] and synthetic amorphous silica (SAS) [CAS No. 7631-86-9]. In the present assessment, this substance is represented by its major component, a treated SAS component. It is noted that D4 is a reaction residual in OMSSA, present at up to 5% of the final composition of this substance. The substance D4, as a discrete substance, has been assessed in 2008 under the Challenge, and it was concluded that it posed an ecological risk.

OMSSA is used in Canada and elsewhere in industrial settings as a component in the production of silicone sealant and silicone rubber. Between 10 000 and 100 000 kg of OMSSA were imported into Canada in 2006.

Given the physico-chemical properties expected and the lack of expected biodegradation of the SAS component of OMSSA, it is very likely that OMSSA is persistent in water, soil and sediments. Based on the available information regarding uptake of the treated SAS, the representative component of OMSSA, through various routes of exposure, OMSSA does not appear to be bioaccumulative in water-, air- or soil-dwelling organisms. Therefore, the substance is proposed to meet the persistence criteria in water, soil and sediment, but not the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations.

There were no ecotoxicological data identified for OMSSA. Based on the experimental data, both surface-treated SAS and untreated SAS present low toxicity to aquatic organisms. Available information regarding the ecological risk associated with the current estimated exposure concentrations of OMSSA in water suggests that OMSSA is unlikely to cause ecological harm in Canada. Therefore, considering the available information, it is proposed that OMSSA 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.

On the basis of the health effects information for an analogue of OMSSA, Silane, dichlorodimethyl-, reaction products with silica, the possible health effects associated with exposure to OMSSA are mainly on the respiratory system. However, the potential for exposure of the general population of Canada to OMSSA from environmental media is expected to be negligible. Exposure to OMSSA from consumer products is not expected because it is only used in industrial settings. Since the exposure of the general population of Canada to OMSSA is expected to be low, the risk to human health is expected to be low. It is, therefore, proposed that OMSSA does not 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.

Proposed conclusion

Based on the information available, it is proposed to conclude that Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, reaction products with ammonia, octamethylcyclotetrasiloxane and silica does not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication after screening assessment of a substanceCarbon black, CAS No. 1333-86-4 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

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

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

Whereas it is proposed to conclude 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.

Public comment period

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

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

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

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

ANNEX

Summary of the Screening Assessment Report of Carbon Black

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 carbon black, Chemical Abstracts Service Registry No. 1333-86-4. This substance was identified as a high priority for screening assessment and included in the Challenge initiative under the Chemicals Management Plan because it was identified as a high priority as it was considered to pose greatest potential for exposure of individuals in Canada and had been classified by other agencies on the basis of carcinogenicity. This substance met the ecological criteria for persistence, but not for bioaccumulation potential and inherent toxicity to aquatic organisms.

In 2006, according to information reported under section 71 of CEPA 1999, 227 900 000 kg of carbon black were manufactured in Canada, and 26 400 000 kg were imported. Carbon black is used primarily in the rubber industry as reinforcing filler and as a pigment in a variety of products, including inks, paints and coatings, and plastics. In Canada, it can also be present in a limited number of food products, cosmetics, pharmaceuticals and natural health products, pesticides, and in food packaging.

In 2006, according to information reported under section 71 of CEPA 1999, 10 000–100 000 kg of carbon black were reported to be released to land, 10 000–100 000 kg to air, and 1 000–10 000 kg to water.

The human health risk characterization focuses on scenarios in which the general population can be exposed to carbon black by inhalation, given the limited potential for exposure and uptake via the oral and dermal routes and the lack of reported acute or chronic toxicity via these routes. No empirical data were identified on the concentrations of carbon black in the environment. Accordingly, exposure from environmental media in the vicinity of a carbon black manufacturing facility was characterized using dispersion modeling. With respect to consumer products, carbon black is used in a large number of paints and coatings, some with potential for inhalation exposure and exposure estimates were derived for these scenarios. Carbon black is also an ingredient in certain costume spray hair dyes and an exposure estimate was derived for these scenarios.

Based principally on the weight-of-evidence-based assessments of international agencies, a critical effect for characterization of risk to human health for carbon black is carcinogenicity. Increased incidences of lung tumours were observed in female rats exposed by inhalation to the only or lowest concentration tested in one 11-month and two 2-year bioassays. However, the weight-of-evidence indicates that the induction of lung tumours in rats following carbon black exposure is caused by an excessive lung burden (i.e. particle overload) due to overwhelming and impairment of clearance mechanisms, resulting in an oxidative state. No evidence was available to indicate carcinogenicity by the oral or dermal routes of exposure. Genotoxicity data indicate that carbon black has the potential to cause DNA and chromosome damage. However, these effects are likely mediated by indirect mechanisms involving inflammation resulting from particle overload in the lungs, resulting in generation of reactive oxygen species, oxidative stress, and oxidative DNA damage. As the tumours observed in animals are considered unlikely to have resulted from direct interaction with genetic material, a margin of exposure approach is used to characterize risk to human health.

The critical effect level for acute pulmonary non-cancer effects by inhalation is a lowest observed effect concentration of 1 mg/m3 in male rats exposed to carbon black for seven hours, based on a significantly higher prevalence of inflammation and oxidative stress as compared to controls. The critical effect level for chronic pulmonary non-cancer effects by inhalation is a lowest observed effect concentration of 0.57 mg/m3, based on increased respiratory symptoms and decreased lung function measurements in individuals (male) exposed to carbon black in an occupational setting.

The margins between upper-bounding estimates of airborne exposure to carbon black in the environment or from consumer products and levels associated with respiratory effects are considered to be 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 carbon black and critical effect levels in animals, it is proposed that carbon black 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.

Carbon black is not soluble, and when released into water it is expected to eventually settle into sediments. It is expected to have very low potential for toxicity to aquatic organisms. Although no environmental monitoring data were identified, conservative estimated exposure concentrations in surface water near industrial sources are below predicted no-effect concentrations. Conservative risk quotient analysis, integrating a predicted environmental concentration with a predicted no-effect concentration resulted in a risk quotient indicating that exposure values are unlikely to be high enough to cause harm to aquatic organisms. Carbon black is resistant to hydrolysis, photolysis and biodegradation; it is therefore persistent in the environment. Accumulation into living organism tissues is not an environmental concern, as carbon black’s physical and chemical properties do not make bioaccumulation possible.

Based on the information available, it is proposed that carbon black 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. Carbon black has been determined to meet the persistence criteria but not the bioaccumulation potential 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.

Proposed conclusion

Based on the information available, it is proposed to conclude that carbon black does not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication after screening assessment of a substancePyridine, alkyl derivs., CAS No. 68391-11-7 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas the substance pyridine, alkyl derivs. is on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

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

Whereas it is proposed to conclude 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.

Public comment period

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

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

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

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

ANNEX

Summary of the Screening Assessment Report of Pyridine, alkyl derivs.

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 pyridine, alkyl derivs., Chemical Abstracts Service Registry No. 68391-11-7. This substance was identified as a high priority for screening assessment and included in the Challenge initiative under the Chemicals Management Plan because it was identified as a high priority as it was considered to pose the greatest 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 but did not meet the criteria for bioaccumulation potential or inherent toxicity to aquatic organisms.

According to information submitted under section 71 of CEPA 1999, pyridine, alkyl derivs. was not reported to be manufactured by any company in Canada during the calendar year of 2006 above the 100 kg reporting threshold. However, 1 000 000–10 000 000 kg of the substance were reported to be imported in 2006. The major use of pyridine, alkyl derivs. is corrosion inhibition of oil and gas wells and pipelines in Canada and is considered the principal source of potential releases to the environment through cleaning/washing of tanker trucks and periodic pipeline leaks under normal operating conditions. More minor uses of pyridine, alkyl derivs. include formulant in one registered herbicide, corrosion inhibitor in industrial cleaning and descaling products for closed water heat transfer systems, and incidental additive in cleaning products for food contact surfaces.

As defined by the Chemical Abstracts Service, pyridine, alkyl derivs. is the complex combination of polyalkylated pyridines derived from coal-tar distillation or as high-boiling distillates approximately above 150°C from the reaction of ammonia with acetaldehyde, formaldehyde or paraformaldehyde. This also corresponds with the Domestic Substances List (DSL) definition. Therefore, this assessment only directly considers the polyalkylated components of the complex mixture. However, commercial versions of the substance in Canada may contain production by-products, such as non-alkylated pyridines, which are considered to be outside of the DSL definition.

Exposure of the general population to pyridine, alkyl derivs. via environmental media was estimated based upon the principal use in Canada, accounting for over 90% of the total use quantity in 2006, namely corrosion inhibition in the oil and gas extraction industry. Conservatively estimated annual release quantities from process and systematic leaks are considered to be negligible. While pyridine, alkyl derivs. is present in some cleaning products for food contact surfaces, dietary exposure for the general population from this source is not expected, as a potable water rinse is required after cleaner application. In addition, while various alkyl pyridines were identified in a variety of foods and beverages, pyridine, alkyl derivs. as a complex mixture defined by the Chemical Abstracts Service would not be expected in foods or beverages and therefore dietary exposure is not expected.

Based on the limited empirical health effects information, it is considered that the major components of pyridine, alkyl derivs. products, within the Chemical Abstracts Service definition, i.e. discrete simple alkylated pyridines such as mono-, di-, tri-methylpyridines, ethylpyridines, methylethylpyridines and propylpyridines, are not highly hazardous. It is likely that the hazard potential of pyridine, alkyl derivs. is due to the presence of by-products in commercial versions of the substance, such as non-alkylated derivatives of pyridine.

As exposure of the general population through environmental media in Canada is expected to be negligible, and exposure is not expected from foods or beverages or consumer products, the risk to human health is considered to be low.

Based on the information available, it is proposed to conclude that pyridine, alkyl derivs. 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.

Based mostly on empirical biodegradation data, the substance is not expected to degrade quickly in the environment. It is persistent in air, water, soil and sediments. This substance does not have the potential to accumulate in organisms or to biomagnify in trophic food chains. The substance has been determined to meet the persistence criteria but not the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations. Empirical aquatic toxicity values indicate that the substance is not highly hazardous to aquatic organisms.

For this screening assessment, a very conservative exposure scenario was selected in which an industrial operation discharges pyridine, alkyl derivs. into the aquatic environment. The predicted environmental concentration in water was many orders of magnitude below predicted no-effect concentrations calculated for green algae.

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.

Proposed conclusion

Based on the information available, it is proposed to conclude that pyridine, alkyl derivs. does not meet any of the criteria set out in section 64 of CEPA 1999.

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

Publication after screening assessment of three substances — 1H-Indene, 2,3-dihydro-1,1,3,3,5-pentamethyl-4,6-dinitro-, CAS No. 116-66-5; Ethanamine, N-ethyl-N-hydroxy-, reaction products with hexamethylcyclotrisiloxane, silica and 1,1,1-trimethyl-N-(trimethylsilyl)silanamine, CAS No. 68583-58-4; and Pyridine, 2-[3-(3-chlorophenyl)propyl]-, CAS No. 101200-53-7 — specified on the Domestic Substances List (subsection 77(1) of the Canadian Environmental Protection Act, 1999)

Whereas 1H-Indene, 2,3-dihydro-1,1,3,3,5-pentamethyl-4,6-dinitro-; Ethanamine, N-ethyl-N-hydroxy-, reaction products with hexamethylcyclotrisiloxane, silica and 1,1,1-trimethyl-N-(trimethylsilyl)silanamine; and Pyridine, 2-[3-(3-chlorophenyl) propyl]- are substances on the Domestic Substances List identified under subsection 73(1) of the Canadian Environmental Protection Act, 1999;

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

Whereas it is proposed to conclude that the substances 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 these substances,

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.

Public comment period

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

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

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

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

ANNEX

Summary of the Screening Assessment of the Three Substances Listed Below

CAS RN*

DSL Name

116-66-5

1H-Indene, 2,3-dihydro-1,1,3,3,5-pentamethyl-4,6-dinitro-

68583-58-4

Ethanamine, N-ethyl-N-hydroxy-, reaction products with hexamethylcyclotrisiloxane, silica and 1,1,1-trimethyl-N(trimethylsilyl)silanamine

101200-53-7

Pyridine, 2-[3-(3-chlorophenyl)propyl]-

* CAS RN = Chemical Abstracts Service Registry Number

The above three substances on the Domestic Substances List (DSL) were identified as high priority for screening assessment, to be part of the Challenge under the Chemicals Management Plan because they meet 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 these substances.

Results from notices issued under paragraph 71(1)(b) of CEPA 1999 on March 4, 2006, and December 26, 2009, as part of the Challenge revealed no reports of industrial activity (import or manufacture) with respect to these substances in Canada, above the reporting threshold of 100 kg, for the specified reporting years of 2005 and 2006, respectively. These results indicate that in 2005 and 2006, these substances were 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 notices issued under paragraph 71(1)(b) of CEPA 1999 and the accompanying questionnaire of December 26, 2009, also revealed no new information relevant to the PBiT properties of these substances. Given the lack of any significant commercial activity for these substances, no further collection or analysis relevant to the persistence, bioaccumulation and ecological effects of these substances, beyond what was done for categorization, has been completed for CAS No. 68583-58-4 and CAS No. 101200-53-7. However, new information on ecotoxicity and environmental fate for CAS No. 116-66-5 has been considered since categorization. The results of an experimental study on biodegradation in water indicate that CAS No. 116-66-5 is not inherently biodegradable and, therefore, is also not readily biodegradable. This result is in agreement with the estimates from three models indicating that CAS No. 116-66-5 is not readily biodegradable. Low experimental water solubility and high experimental log Kow values suggest that CAS No. 116-66-5 is a lipophilic substance which is expected to be bioaccumulative in aquatic organisms. Using experimental water solubility and log Kow values as inputs in bioconcentration/ bioaccumulation models, the modelled data indicate that the bioconcentration potential of this substance is very high. Two additional ecotoxicological studies for CAS No. 116-66-5 studies have been identified. The results from these studies were considered as inconclusive and contradictory. The study by Schramm et al. (1996) contains an inconclusive result (no effects at saturation, i.e. EC50 > 0.046 mg/L). In another study, a statistically significant reduction of viability of frog larvae (62% to 94%) was observed. New experimental and modelled data confirm that this substance is highly persistent and bioaccumulative as defined in the Persistence and Bioaccumulation Regulations of CEPA 1999, and has inherent toxicity.

As mentioned above, given the lack of evidence that these substances are in use in Canada or abroad, since the results from notices issued under paragraph 71(1)(b) of CEPA 1999 on March 4, 2006, and September 26, 2009, indicate that these substances are 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, 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.

Proposed conclusion

Based on available information, and until new information is received indicating that these substances are entering, or may enter the environment, from commercial activity or from other sources, it is proposed to conclude that the above substances are currently not entering or likely to enter the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity or constitute a danger to the environment on which life depends or that constitute a danger in Canada to human life or health. Therefore, it is proposed to conclude that they do not meet any of the criteria as 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 (persistence, bioaccumulation and inherent toxicity), 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.

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