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August 4, 2016

Canada Begins Consultation on Proposed Prioritization Approach for Nanoscale Forms of DSL Substances

Lynn L. Bergeson Carla N. Hutton

On July 27, 2016, Environment and Climate Change Canada (ECCC) and Health Canada (HC) began a consultation on a proposed prioritization approach for nanoscale forms of substances on the Domestic Substances List (DSL).  Canada will use the proposed approach to:  (1) establish a list of existing nanomaterials in Canada for prioritization; (2) identify how the information available will be used to inform prioritization of nanomaterials for risk assessment; and (3) outline the proposed outcomes of the prioritization process.  In 2015, Canada conducted a mandatory survey under Section 71 of the Canadian Environmental Protection Act, 1999 (CEPA).  The survey applied to persons who manufactured or imported any of 206 nanomaterials at a quantity greater than 100 kilograms (kg) during the 2014 calendar year.  Based on the results of the survey, ECCC and HC will prepare a final list of confirmed existing nanomaterials in Canada and will use the list for subsequent prioritization.  ECCC and HC propose that, where possible, the substances identified via the survey be “rolled up into” their broader parent nanomaterial groups for the purposes of prioritization.  According to ECCC and HC, this will allow, when possible, a more robust look at the hazard, volume, and use data as appropriate, rather than considering an individual substance-by-substance approach.  ECCC and HC state that further consideration for sub-grouping (such as by use, unique property, or functionalization) may need to be considered for prioritization and/or risk assessment.  The 21 possible nanomaterial groupings, based on parent substance, include:

Aluminum oxide

Iron (II)/(II/III) oxide

Modified silica

Bismuth oxide

Magnesium oxide

Silicon oxide

Calcium carbonate

Manganese (II & III) oxide


Cerium oxide


Titanium dioxide

Cobalt (II) oxide


Yttrium oxide

Copper (II) oxide

Nickel (II) oxide

Zinc oxide


Quantum dots

Zirconium oxide

To prioritize the nanomaterials, ECCC and HC will consider multiple sources of information, including volume and use pattern information from the survey, routes of exposure, and scientific information on hazard.  ECCC and HC will determine human and ecological exposure separately using information obtained from the survey such as information on volume, sector (based on reported North American Industry Classification System (NAICS) codes), and use (based on reported substance function code).  ECCC and HC state that nanomaterials that were not reported during the survey and received no voluntary submissions of information will be considered as not in commerce and no further action will be taken on these nanomaterials as a result of prioritization.  Direct human exposure will be ranked as:

  • Low: Substances with only industrial and/or commercial applications (e., no consumer use) or substances contained in manufactured items, but not subject to leaching;
  • Moderate: Substances contained in manufactured items subject to possible leaching during normal use; or
  • High: Substances directly used by consumers, contained in consumer products, or in manufactured items intended for use by or for children.

Prioritization for ecological exposure will be based on information reported through the survey, including consideration of the volumes used in Canada, and on three possible types of environmental exposures scenarios:

  1. Manufacturing of the nanomaterial;
  2. Manufacturing the final end-use product; and/or
  3. Use of the end-use product.

To rank the potential hazards to human health and the environment, ECCC and HC will consider information from a variety of sources, including peer-reviewed literature, information available from other government of Canada activities (e.g., Chemicals Management Plan (CMP)) and international reports and activities (e.g., Organization for Economic Cooperation and Development dossiers).  ECCC and HC will rank the human health hazard by considering the properties of the nanomaterial as well as any available information on toxicological effects of the nanomaterial itself (e.g., outcomes of available toxicological studies).  ECCC and HC will rank the ecological hazard by looking at the most sensitive endpoint across all compartments (e.g., soil, sediment, air, and water), species, and exposure durations, using studies that conform to standardized and accepted test guidelines.  The results of prioritization will be no further action at this time; nanomaterials prioritized for risk assessment; and nanomaterials that will be set aside for future consideration due to insufficient information.  Comments on the proposed prioritization approach are due September 25, 2016.