• Previously listed on the First Priority Substances List (PSL1)
  • Concluded to have impacts on the environment
  • Added to Schedule 1 to CEPA 1999

Tetrachlorobenzenes were one of the 44 substances or groups of substances placed on the First Priority Substances List (PSL1) to determine whether they posed a risk to the health of Canadians or to the environment.

Assessment Status and Conclusion

Environment Canada and Health Canada have completed the ecological and human health assessment of tetrachlorobenzenes.

The PSL1 assessment on tetrachlorobenzenes was jointly conducted by Enviroment Canada and Health Canada. The PSL1 assessment report was published in 1993, and concluded that either tetrachlorobenzenes or any isomers of tetrachlorobenzenes were not harmful to human life or health. However, there was insufficient information to conclude whether tetrachlorobenzenes were harmful to the environment.

The follow-up to PSL1 assessment was conductec by Environment Canada. The follow-up report was published in 2003, and concluded that tetrachlorobenzenes were 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.

Tetrachlorobenzenes are considered "toxic", as defined under Paragraph 64(a) of CEPA 1999, and have been added to Schedule 1 to CEPA 1999. For information of risk management for tetrachlorobenzenes, please refer to Management of Toxic Substances website.

Related Information


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