Benzotriazoles and Benzothiazoles Group

These substances were identified for action under the Chemicals Management Plan (CMP). The screening assessment focuses on 15 substances referred to collectively under the CMP as the Benzotriazoles and Benzothiazoles Group. The substances in the benzothiazoles subgroup all contain the 2-mercaptobenzothiazole (MBT) moiety; therefore, the conclusion for this subgroup includes MBT and substances that are precursors to MBT, and is not limited to the 6 substances in the table below.

• Summary of publications
• Timelines
• Information gathering
  • Section 71 CMP 2023
• Background

Summary of publications

Substance group	Subgroup	CAS RN	Common name or acronym	DSL name	Draft screening assessment	Risk management scope	Proposed conclusion on section 64 criteria	Follow-up activities
Benzotriazoles and Benzothiazoles Group	Benzotriazoles	95-14-7Footnote a	Benzotriazole	1H-Benzotriazole	HTML	none	Do not meet	None planned at this time.
		3147-75-9	UV-329	Phenol, 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)-
		3846-71-7Footnote a	UV-320	Phenol, 2-(2H-benzotriazol-2-yl)-4,6-bis(1,1-dimethylethyl)-
		3896-11-5	UV-326	Phenol, 2-(5-chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methyl-
		29385-43-1Footnote b	Tolyltriazole	1H-Benzotriazole, 4(or 5)-methyl-
		36437-37-3	UV-350	Phenol, 2-(2H-benzotriazol-2-yl)-4-(1,1-dimethylethyl)-6-(1-methylpropyl)-
		70321-86-7	UV-234	Phenol, 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)-
		80595-74-0	n/a	1H-Benzotriazole-1-methanamine, N,N-bis(2-ethylhexyl)-5-methyl-
		94270-86-7Footnote b	n/a	1H-Benzotriazole-1-methanamine, N,N-bis(2-ethylhexyl)-ar-methyl-
	Benzothiazoles	95-31-8a	TBBS	2-Benzothiazolesulfenamide, N-(1,1-dimethylethyl)		HTML	Meet one or more of the criteria	Under consideration. For MBT and its precursors, refer to risk management scope.
		95-33-0Footnote a	CBS	2-Benzothiazolesulfenamide, N-cyclohexyl-
		120-78-5Footnote c	MBTS	Benzothiazole, 2,2'-dithiobis-
		149-30-4	MBT	2(3H)-Benzothiazolethione
		2492-26-4	SMBT	2(3H)-Benzothiazolethione, sodium salt
		4979-32-2	DCBS	2-Benzothiazolesulfenamide, N,N-dicyclohexyl-

Timelines

Date	Activity
March 2024	Anticipated publication of the Final Screening Assessment for the Benzotriazoles and Benzothiazoles Group and the proposed Risk Management Approach for 2-Mercaptobenzothiazole (MBT) and its Precursors.
June 24, 2023	Publication in Canada Gazette, Part I, of a notice under section 71 of CEPA 1999.
March 6, 2021	Publication and start of 60-day public comment period on the Draft Screening Assessment for the Benzotriazoles and Benzothiazoles Group (including follow-up activities for TBBS, CBS, MBTS, MBT, SMBT, and DCBS) and the Risk Management Scope for 2-Mercaptobenzothiazole (MBT) and its Precursors. The related notice was published in the Canada Gazette, Part I: Vol. 155, No. 10.

Information gathering

Section 71 CMP 2023

In June 2023, a notice was published in the Canada Gazette, Part I: Vol. 157, No. 25 – June 24, 2023 under section 71 of CEPA 1999. This notice applies to 11 benzothiazole substances. More information is available on the Information gathering with respect to certain substances under the Chemicals Management Plan web page.

Background

Two other substances were identified as being part of the Benzotriazoles and Benzothiazoles Group at the outset of the third phase of the CMP. These substances (CAS RNs 80584-90-3 and 21564-17-0) were subsequently determined to be of low concern to both human health and the environment through other approaches. The conclusion for CAS RN 80584-90-3 is provided in the Final Screening Assessment for Substances Identified as Being of Low Concern using the Ecological Risk Classification of Organic Substances and the Threshold of Toxicological Concern (TTC)-based Approach for Certain Substances. The conclusion for CAS RN 21564-17-0 is provided in the Final Screening Assessment for the Rapid Screening of Substances with Limited General Population Exposure.