Notice of the second release of technical information for the batch 2 Challenge Substances was published in the Canada Gazette Part I on May 12, 2007.

On December 9, 2006, the Government of Canada published the Notice of Intent to Develop and Implement Measures to Assess and Manage the Risks Posed by Certain Substances to the Health of Canadians and Their Environment in which it highlighted how it intended to address approximately 200 chemical substances identified as high priorities for action. The substances were characterized as high priority for action based on the following criteria: (1) the substances were identified as being persistent and bio-accumulative, and when combined with evidence of toxicity and releases into the environment, could either lead to harmful ecological impacts, or (2) there is evidence that the substances may be mutagenic carcinogens and that there is a probability of harm to human health at any level of exposure, or (3) there is evidence that the substances exhibit carcinogenicity, mutagenicity, developmental toxicity, or reproductive toxicity.

The Notice requires any person who during the 2006 calendar year, manufactured or imported a total quantity greater than 100 kg of a substance or used a total quantity greater than 100 kg whether alone, in a mixture, in a product or in a manufactured item, at a concentration greater than 50%, to make a mixture, product or manufactured item, or who during the 2006 calendar year, used a total quantity greater than 10,000 kg at any concentration, to provide information relating to the substance. The information required to be provided includes the Chemical Abstracts Service Registry Number (CAS RN), the type of mixture, the concentration, the use pattern, the quantity and the trade names of the products in which the substance appears. Information is required on the total quantity released to the environment or transferred to an off-site waste management facility. A description of procedures and policies to prevent or minimize releases, and studies or data in respect of those substances is also required to be provided.

If new information for the 17 batch 2 substances is not received by November 13, 2007, then by no later than February 16, 2008, there will be a 60 day public comment period on the screening assessment for the substances and a proposal to pursue measures in respect of the substances, including restrictions on use and potential bans on the use of both substances. If information is received by November 13, 2007, then that information will be considered and by no later than May 17, 2008, a 60 day comment period will commence on the screening assessment and potential measures to control the future use or limit the use of the substances.

The batch 2 Challenge substances identified as persistent, bioaccumulative, and inherently toxic to non-human organisms and believed to be in commercial use in Canada are:


Substance Name±


Cyclohexasiloxane, dodecamethyl-


Cyclopentasiloxane, decamethyl-


Cyclotetrasiloxane, octamethyl-


Phenol, 2,4,6-tris(1,1-dimethylethyl)-


Benzene, 1,3-bis(1-isocyanato- 1 – methylethyl)-


Benzenesulfonic acid, 3,3'-[9,10-dihydro-9, 10-dioxo-1,4-anthracenediyl)diimino]bis[2,4,6-trimethyl-,disodium salt


Spiro[isobenzofuran-1(3 H ),9'-[9 H ]xanthen]-3-one, 2',4',5',7'-tetrabromo-3',6'-dihydroxy-


Benzenesulfonic acid, [(9,10-dihydro-9,10-dioxo-1,4-anthracenediyl)bis(imino-4,1-phenyleneoxy)]bis-, disodium salt


Benzenesulfonic acid, 2,2'-[9,10-dihydro-5,8-dihydroxy-9,10-dioxo-1,4-anthracenediyl)diimino]bis[5-(1,1-dimethylethyl)-, disodium salt


9,10-Anthracenedione, 1,4-bis[4-methylphenyl)amino]-, sulfonated, potassium salts

Eight substances are identified as presenting a high hazard to humans and a high likelihood of exposure to individuals in Canada:


Substance Name±




1,3-Butadiene, 2-methyl-


Phenol, 4,4'-(1-methylethylidene)bis-


Oxirane, (chloromethyl)-


Acetic acid ethenyl ester


Cyclotetrasiloxane, octamethyl-


C.I. Pigment Yellow 34


C.I. Pigment Red 104