PBiT substances risk assessment and order amending the Domestic Substances List
The results of categorization indicated that there were 397 substances on the Domestic Substances List (DSL) that are Persistent, Bioaccumulative and inherently Toxic (PBiT) to non-human organisms, according to the categorization criteria. Preliminary research indicated that a high percentage of these substances may no longer be manufactured in or imported into Canada. To establish whether this was the case, surveys were conducted on these substances in 2001 and 2006 by issuing notices in the Canada Gazette, Part I, pursuant to paragraphs 71(1)(a) and (b) of the Canadian Environmental Protection Act, 1999 (CEPA). There were no reports of industrial activity with respect to 148 of these PBiT substances; therefore, the likelihood of exposure to these substances in Canada resulting from commercial activity was considered to be low.
On this page
- Significant New Activity (SNAc) provisions
- Significant New Activity Notification (SNAN) risk assessment summary
- Aromatic Azo and Benzidine-based Substance Grouping
- Final screening assessment
- Background
Significant New Activity (SNAc) provisions
View the SNAc publications under CEPA. Orders are subject to potential amendments under the SNAc Review.
Applying SNAc provisions
In June 2008, an order amending the DSL to apply the SNAc provisions of CEPA to 145 substances was published:
In December 2006, a notice of intent to apply the SNAc provisions of CEPA to the 148 PBiT substances was published for a public comment period. On this basis of new information received during the public comment period, three of the initial 148 PBiT substances were no longer considered eligible for the application of the SNAc provisions:
- CAS RN 13080-86-9
- CAS RN 71032-95-6
- CAS RN 71832-83-2
As a part of the SNAc Review, requirements under the SNAc provisions have been varied for 85 PBit substances and rescinded 52 PBit substances. The SNAc requirements on the remaining eight of the 145 PBiT substances have been maintained and will be revised, as needed, under appropriate groups as part of the SNAc Review.
For additional guidance on submitting information required as part of SNAc notifications, please see the Guidance document for the New Substances Notification Regulations (Chemicals and Polymers).
Varying the requirements under the SNAc provisions
In March 2026, an order amending the DSL to vary the requirements under the SNAc provisions of CEPA for 85 PBiT substances was published in the Canada Gazette, Part II: Vol. 160, No. 6 – March 25, 2026. The amendments are an outcome of the SNAc Review.
Rescinding the requirements under the SNAc provisions
In August 2024, an order rescinding the requirements under the SNAc provisions of CEPA for three PBiT substances (CAS RNs 93918-79-7, 113089-51-3 and 119209-64-2) was published in the Canada Gazette, Part II, Vol. 158, No.17 – August 14, 2024. These three substances were subject to the SNAc provisions as a result of the 2008 assessment of 145 PBiT substances. Since then, these substances were included in the High Hazard Not in Commerce Substances SNAc Review Group, under the SNAc Review. That review led to the recommendation that the requirements under the SNAc provisions for these substances be rescinded.
In July 2017, an order rescinding the requirements under the SNAc provisions of CEPA for 32 PBiT substances was published in the Canada Gazette, Part II: Vol. 151, No.14 – July 12, 2017. These 32 substances were subject to the SNAc provisions as a result of the 2008 assessment of 145 PBiT substances. Since then, these substances were included in the Certain Azo Disperse Dyes Subgroup, assessed in2017 and concluded to no longer be of concern to the environment.
In October 2016, an order rescinding the requirements under the SNAc provisions of CEPA for six PBiT substances (CAS RNs 71720-89-3, 83027-51-4, 83027-52-5, 90218-20-5, 90459-02-2, and 114910-04-2) was published in the Canada Gazette, Part II: Vol. 150, No. 21 - October 19, 2016. These six substances were subject to the SNAc provisions as a result of the 2008 assessment of 145 PBiT substances. Since then, these six substances were included in the Certain Azo Acid Dyes Subgroup, assessed in 2016, and concluded to not pose a risk to the environment or human health.
In October 2016, an order rescinding the requirements under the SNAc provisions of CEPA for CAS RN 59709-10-3 was published in the Canada Gazette, Part II: Vol. 150, No. 21 - October 19, 2016. CAS RN 59709-10-3 was subject to the SNAc provisions as a result of the 2008 assessment of 145 PBiT substances. Since then, CAS RN 59709-10-3 was included in the Certain Azo Basic Dyes Subgroup, assessed in 2016, and concluded to not pose a risk to the environment or human health.
In October 2016, an order rescinding the requirements under the SNAC provisions of CEPA for 5 PBiT substances (CAS RNs 2653-64-7, 73528-78-6, 85392-21-8, 85005-63-6, and 94199-57-2) was published in the Canada Gazette, Part II: Vol. 150, No. 21 - October 19, 2016. These 5 substances were subject to the SNAc provisions as a result of the 2008 assessment of 145 PBiT substances. Since then, these 5 substances were included in the Certain Azo Solvent Dyes and Certain Monoazo Pigments subgroupings, assessed in 2016, and concluded to not pose a risk to the environment or human health.
In March 2015, an order rescinding the requirements under the SNAc provisions of CEPA for CAS RN 1871-22-3 was published in the Canada Gazette, Part II: Vol. 149, No. 5 - March 11, 2015. CAS RN 1871-22-3 was subject to the SNAc provisions as a result of the 2008 assessment of 145 PBiT substances. Since then, CAS RN 1871-22-3 was included in the Certain Benzidine-based Dyes and Related Substances Subgroup, assessed in 2014, and concluded to not meet the criteria for bioaccumulation or inherent toxicity to aquatic organisms.
In December 2014, an order rescinding the requirements under the SNAc provisions of CEPA for CAS RN 78952-70-2 was published in the Canada Gazette, Part II: Vol. 148, No. 26 - December 17, 2014. CAS RN 78952-70-2 was subject to the SNAc provisions as a result of the 2008 assessment of 145 PBiT substances. Since then, CAS RN 78952-70-2 was included in the Certain Diarylide Yellow Pigments Subgroup, assessed in 2014, and concluded to not meet the criteria for bioaccumulation or inherent toxicity to aquatic organisms.
In July 2014, an order rescinding the requirements under the SNAc provisions of CEPA for three PBiT substances (CAS RNs 92-72-8, 92-76-2, and 135-63-7) was published in the Canada Gazette, Part II: Vol.148, No. 16 - July 30, 2014 rescinding. These three substances were subject to the SNAc provisions as a result of the 2008 assessment of 145 PBiT substances. Since then, a review and analysis of new information related to the three substances was undertaken, and the 2013 assessment concluded that these substances are no longer considered to meet categorization criteria for bioaccumulation or inherent toxicity. Therefore, future use of these substances is no longer considered a potential concern to the environment.
Significant New Activity Notification (SNAN) risk assessment summary
One substance in this batch has been assessed for new activities notified through a SNAN. One SNAN risk assessment summary has been published:
Aromatic Azo and Benzidine-based Substance Grouping
The following substances in this initiative have been included in the Aromatic Azo and Benzidine-based Substance Grouping under the Substance Groupings Initiative. As outlined in the notice of intent for this substance grouping, it was recognized that assessments and conclusions pertaining to some of the substances in this grouping may be subsequently updated as part of the subgroup assessment. The latest updates on the following substances can be found on the respective Aromatic Azo and Benzidine-based Substance Grouping web pages.
| CAS RN | Chemical substance | Subgroup |
|---|---|---|
| 1871-22-3 | 2H-Tetrazolium, 3,3'-(3,3'-dimethoxy[1,1'-biphenyl]-4,4'-diyl)bis[2,5-diphenyl-, dichloride (TDBD) | Certain Benzidine-based Dyes and Related Substances |
| 2537-62-4 | Acetamide, N-[2-[(2-bromo-6-cyano-4-nitrophenyl)azo]-5-(diethylamino)phenyl]- | Certain Azo Disperse Dyes |
| 2653-64-7 | Solvent Red 4 | Certain Azo Solvent Dyes |
| 3701-40-4 | Acid Red 99 | Benzidine-based Dyes and Related Substances |
| 6368-72-5 | Solvent Red 19 | Certain Azo Solvent Dyes |
| 6420-06-0 | Direct Violet 28 | Certain Benzidine-based Dyes and Related Substances |
| 6465-02-7 | Carbamic acid, [4-[[4-[(4-hydroxyphenyl)azo]-2-methylphenyl]azo]phenyl]-, methyl ester | Certain Azo Disperse Dyes |
| 15958-27-7 | Propanenitrile, 3-[[4-[(4-nitrophenyl)azo]phenyl][2-[[(phenylamino)carbonyl]oxy]ethyl]amino]- | |
| 19745-44-9 | Propanenitrile, 3-[4-[(5-nitro-2-thiazolyl)azo](2-phenylethyl)amino]- | |
| 24610-00-2 | Benzonitrile, 2-[[4-[(2-cyanoethyl)(2-phenylethyl)amino]phenyl]azo]-5-nitro- | |
| 25150-28-1 | Propanenitrile, 3-[[4-[(6,7-dichloro-2-benzothiazolyl)azo]phenyl]ethylamino]- | |
| 28824-41-1 | Propanenitrile, 3-[[4-[(4,6-dibromo-2-benzothiazolyl)azo]phenyl]ethylamino]- | |
| 31030-27-0 | Benzenamine, 4-[(2-chloro-4-nitrophenyl)azo]-N-ethyl-N-(2-phenoxyethyl)- | |
| 33979-43-0 | Propanenitrile, 3-[[2-(acetyloxy)ethyl][4-[(5,6-dichloro-2-benzothiazolyl)azo]phenyl]amino]- | Certain Azo Disperse Dyes |
| 41362-82-7 | Propanenitrile, 3-[[4-[(5,6-dichloro-2-benzothiazolyl)azo]phenyl]methylamino]- | |
| 42852-92-6 | Acetamide, N-[2-[(2-bromo-4,6-dinitrophenyl)azo]-4-methoxy-5-[(phenylmethyl)-2-propenylamino]phenyl]- | |
| 55252-53-4 | Acetamide, N-[2-[(2-cyano-6-iodo-4-nitrophenyl)azo]-5-(diethylamino)phenyl]- | |
| 56532-53-7 | Acetamide, N-[2-[(2,6-dicyano-4-nitrophenyl)azo]-5-(dipropylamino)phenyl]- | |
| 59709-10-3 | Pyridinium, 1-[2-[[4-[(2-chloro-4-nitrophenyl)azo]phenyl]ethylamino]ethyl]-, acetate | Certain Azo Basic Dyes |
| 61799-13-1 | 3-Pyridinecarbonitrile, 5-[(2-cyano-4-nitrophenyl)azo]-2-[(2-hydroxyethyl)amino]-4-methyl-6-[[3-(2-phenoxyethoxy)propyl]amino]- | Certain Azo Disperse Dyes |
| 63133-84-6 | 1(2H)-Quinolineethanol, 6-[(2-chloro-4,6-dinitrophenyl)azo]-3,4-dihydro-2,2,4,7-tetramethyl- | |
| 63134-15-6 | Disperse Red 338 | |
| 63281-10-7 | 3-Pyridinecarbonitrile, 5-[[2-chloro-4-(methylsulfonyl)phenyl]azo]-4-methyl-2,6-bis[[3-(2-phenoxyethoxy)propyl]amino]- | Certain Azo Metal Complexes and Other Azo Substances |
| 63833-78-3 | 3-Pyridinecarbonitrile, 5-[(2-cyano-4-nitrophenyl)azo]-6-[(2-hydroxyethyl)amino]-4-methyl-2-[[3-(2-phenoxyethoxy)propyl]amino]- | Certain Azo Disperse Dyes |
| 68214-66-4 | Carbamic acid, [2-[(2-chloro-4-nitrophenyl)azo]-5-(diethylamino)phenyl]-, 2-ethoxyethyl ester | |
| 68400-36-2 | 2,7-Naphthalenedisulfonic acid, 4-amino-5-hydroxy-6-[[4'-[(4-hydroxyphenyl)azo]-3,3'-dimethyl[1,1'-biphenyl]-4-yl]azo]-3-[(4-nitrophenyl)azo]-, disodium salt (NAAHD) | Certain Benzidine-based Dyes and Related Substances |
| 68516-64-3 | Propanenitrile, 3-[[2-(acetyloxy)ethyl][4-[(2-chloro-4-nitrophenyl)azo]-3-methylphenyl]amino]- | Certain Azo Disperse Dyes |
| 68877-63-4 | Acetamide, N-[2-[(2-bromo-4,6-dinitrophenyl)azo]-5-[(2-cyanoethyl)-2-propenylamino]-4-methoxyphenyl]- | |
| 70210-08-1 | Disperse Red 151 | |
| 70660-55-8 | 1-Naphthalenamine, 4-[(2-bromo-4,6-dinitrophenyl)azo]-N-(3-methoxypropyl)- | |
| 71720-89-3 | 2-Naphthalenesulfonic acid, 5-[[4-(4-cyclohexylphenoxy)-2-sulfophenyl]azo]-6-[(2,6-dimethylphenyl)amino]-4-hydroxy-, disodium salt | Certain Azo Acid Dyes |
| 72828-63-8 | Benzonitrile, 2-[[4-[[2-(acetyloxy)ethyl]butylamino]-2-methylphenyl]azo]-3-bromo-5-nitro- | Certain Azo Disperse Dyes |
| 72828-64-9 | Disperse Blue 287 | |
| 73003-64-2 | 2,4,10-Trioxa-7-azaundecan-11-oic acid, 7-[4-[(2,6-dichloro-4-nitrophenyl)azo]-3-methylphenyl]-3-oxo-, methyl ester | |
| 73398-96-6 | Disperse Brown 21 | |
| 73528-78-6 | 3-Pyridinecarbonitrile, 5-[[4-[(2,6-dichloro-4-nitrophenyl)azo]-2,5-dimethoxyphenyl]azo]-2,6-bis[(2-methoxyethyl)amino]-4-methyl- | Certain Azo Solvent Dyes |
| 78952-70-2 | Butanamide, 2-[[3,3'-dichloro-4'-[[1-[[(2-chlorophenyl)amino]carbonyl]-2-oxopropyl]azo][1,1'-biphenyl]-4-yl]azo]-N-(2,4-dimethylphenyl)-3-oxo-(CPAOBP) | Certain Diarylide Yellow Pigments |
| 79542-46-4 | Disperse Red 349 | Certain Azo Disperse Dyes |
| 83027-52-5 | 1,7-Naphthalenedisulfonic acid, 6-[[2-(2-cyclohexylphenoxy)phenyl]azo]-4-[[(2,4-dichlorophenoxy)acetyl]amino]-5-hydroxy-, disodium salt | Certain Azo Acid Dyes |
| 83027-51-4 | 1,7-Naphthalenedisulfonic acid, 6-[[2-(4-cyclohexylphenoxy)phenyl]azo]-4-[[(2,4-dichlorophenoxy)acetyl]amino]-5-hydroxy-, disodium salt | |
| 83249-47-2 | Acetamide, N-[2-[(2-bromo-6-cyano-4-nitrophenyl)azo]-5-(dipropylamino)phenyl]- | Certain Azo Disperse Dyes |
| 83249-49-4 | Benzonitrile, 3-bromo-2-[[4-(diethylamino)-2-methylphenyl]azo]-5-methyl- | |
| 83249-53-0 | Methanesulfonamide, N-[2-[(2-bromo-6-cyano-4-methylphenyl)azo]-5-(diethylamino)phenyl]- | |
| 83249-54-1 | Methanesulfonamide, N-[2-[(2-bromo-6-cyano-4-methylphenyl)azo]-5-(dipropylamino)phenyl]- | |
| 85005-63-6 | 2-Naphthalenecarboxamide, 4-[(2,4-dinitrophenyl)azo]-3-hydroxy-N-phenyl- (NANPAP) | Certain Monoazo Pigments |
| 85392-21-8 | 3-Pyridinecarbonitrile, 5-[[2-chloro-4-(phenylazo)phenyl]azo]-2,6-bis[(3-methoxypropyl)amino]-4-methyl- | Certain Azo Solvent Dyes |
| 90218-20-5 | Benzenesulfonic acid, 5-amino-2,4-dimethyl-, diazotized, coupled with diazotized 2,4-, 2,5-and 2,6-xylidine and 4-[(2,4-dihydroxyphenyl)azo]benzenesulfonic acid, sodium salts | Certain Azo Acid Dyes |
| 90459-02-2 | 2,7-Naphthalenedisulfonic acid, 5-amino-4-hydroxy-3-[[6-sulfo-4-[(4-sulfo-1-naphthalenyl)azo]-1-naphthalenyl]azo]-, diazotized, coupled with diazotized 4-nitrobenzenamine and resorcinol, potassium sodium salts | |
| 90729-40-1 | 3-Pyridinecarbonitrile, 1-butyl-5-[[4-(4-chlorobenzoyl)-2-nitrophenyl]azo]-1,2-dihydro-6-hydroxy-4-methyl-2-oxo- | Certain Azo Disperse Dyes |
| 94199-57-2 | 2-Naphthalenecarboxamide, N-(2-ethoxyphenyl)-3-hydroxy-4-[(2-nitrophenyl)azo]- (NAPNPA) | Certain Monoazo Pigments |
| 127126-02-7 | Propanenitrile, 3-[[2-(acetyloxy)ethyl][4-[(6,7-dichloro-2-benzothiazolyl)azo]phenyl]amino]- | Certain Azo Disperse Dyes |
Final screening assessment
In April 2008, the Final Screening Assessment for Potentially Toxic Substances (145 PBiT substances) was published. The final screening assessment concluded that none of these 145 substances met any of the criteria set out under section 64 of CEPA. Therefore, it was recommended to take no further action on these substances at that time.
New information was received during the public comment period on the draft screening assessment and the notice of intent to apply the SNAc provisions of CEPA to 148 PBiT substances:
- For CAS RNs 13080-86-9 (BAPP - Batch 12) and 71032-95-6 (NDTHPM - Batch 9), evidence was provided indicating that they are presently in commerce in Canada
- Therefore, these substances were added to and assessed under the Challenge Initiative.
- For CAS RN 71832-83-2 (Pigment Red 48:5), it was been found to no longer meet the categorization criteria for bioaccumulation and inherent toxicity
- Therefore, this substance was added to the Aromatic Azo and Benzidine-based Substance Grouping and was assessed under the Certain Monoazo Pigments Subgroup
Draft screening assessment
In December 2006, the Draft Screening Assessment for 148 Substances on the Domestic Substances List was released and the related notice was published in the Canada Gazette, Part I: Vol. 145 No. 27 – December 9, 2006 for a 60-day public comment period.
The draft screening assessment proposed to conclude that these substances do not meet any of the criteria set out in section 64 of CEPA.
Background
The results of categorization indicated that there were 397 substances on the DSL that were PBiT to non-human organisms, according to the categorization criteria. Preliminary research indicated that a high percentage of these substances were no longer being manufactured in or imported into Canada. To establish whether this was the case, surveys were conducted on these substances in 2001 and 2006 by issuing notices pursuant to paragraphs 71(1)(a) and (b) of CEPA in the Canada Gazette, Part II.
Based on the survey results, there were no reports of industrial activity (import or manufacture) with respect to 148 of these PBiT substances in Canada above the reporting threshold of 100 kg for the specified reporting years. These results suggested that the likelihood of exposure to these substances in Canada resulting from commercial activity at that time was low. In addition, no companies identified themselves as having an interest in any of the substances listed in the 2006 notice, providing further evidence that these substances were not of commercial interest in Canada.