Canada announced on January 9, 2015, that the New Substances Program has published six new risk assessment summaries for chemicals and polymers, including a summary for multi-wall carbon nanotubes. Environment Canada and Health Canada conduct risk assessments on new substances. These assessments include consideration of information on physical and chemical properties, hazards, uses, and exposure to determine whether a substance is or may become harmful to human health or environment as set out in Section 64 of the Canadian Environmental Protection Act, 1999 (CEPA 1999), and, if harm is suspected, to introduce any appropriate or required control measures. The risk assessment conclusion for multi-wall carbon nanotubes states:
When used as notified, the substance is not suspected to be harmful to human health or the environment according to the criteria under section 64 of CEPA 1999. However it is suspected that a significant new activity in relation to the substance may result in the substance meeting those criteria.
Due to the potential risk to the environment (related to aquatic, soil, and sediment toxicity) and due to the potential risk to the general population (related to respiratory toxicity, immunotoxicity, cardiovascular toxicity and carcinogenicity following oral and inhalation exposure) if the substance is used in increased amounts or in consumer products, a SNAc notice was issued to obtain information to ensure that the substance, in relation to these potential activities, undergoes further assessment. SNAc notice No. 17192 was published in the Canada Gazette Part I, Vol. 147, No. 34 – August 24, 2013.
A conclusion under CEPA 1999, on this substance, is not relevant to, nor does it preclude, an assessment against the hazard criteria for WHMIS that are specified in the Controlled Products Regulations for products intended for workplace use.