Toxic substances list: tetrachlorobenzenes (TeCBs)

Tetrachlorobenzenes (TeCBs) are not currently produced or used in their pure form in Canada, and there is currently no domestic commercial demand for TeCBs. Formerly, they could be found in dielectric fluids where they were used to top up polychlorinated biphenyl (PCB) transformers and in dyestuff carriers. These applications have either been discontinued (dye carriers) or are being phased out (dielectric fluids). A possible source of release may include dielectric PCB material still in use. TeCBs may be generated when organic compounds are burned or exposed to a large source of energy in the presence of a chlorine source. Through this mechanism, they may be formed and released to the environment as a result of waste incineration and barrel burning of household waste.

CAS (Chemical Abstracts Service) registry numbers: 12408-10-5, 84713-12-2, 634-90-2, 634-66-2 and 95-94-3.

Risk assessment


This substance is entering the environment from the following source(s):

Risk management strategy

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Risk management tools

Tool(s) developed to manage risks associated with the substance:

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Other information


Chemicals Management Division
Environment and Climate Change Canada
Gatineau, QC K1A 0H3


Substances Management Information Line:
Telephone: 1-800-567-1999 (in Canada) or 819-938-3232
Fax: 819-938-3231


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