https://tc.canada.ca/en/dangerous-goods/marks-safety
Explosive and toxic marking.
1.4 A substance or article which presents no significant hazard; explosion effects are largely confined to the package and no projection or fragments of appreciable size or range are to be expected.
6.1 A solid or liquid that is toxic through inhalation, by skin contact or by ingestion.
Commonly used as a germicide or general disinfectant (example: phenol).
Probably smoke and/or CS gas. Probably not enough to clear a large area.
More concerned about if those cartridges are rubber or lead. Hard to tell but it looks like cheap Federal 556.