Summary of public comments received on the draft screening assessment and risk management scope for the other polymers group

Comments on the draft Screening Assessment and Risk Management Scope for Other Polymers Group, assessed under the Chemicals Management Plan (CMP), were submitted by Canadian Consumer Specialty Products Association, Sherwin-Williams Canada Inc. and an individual. Summarized public comments and responses are provided below, organized by topic.

Occupational exposure

Comment summary 1: Information related to occupational exposure was provided and requested to be taken into consideration in the development of the final screening assessment.

Response 1: Screening assessments conducted under CEPA focus on risks of exposure to the general population, rather than risks of exposures in the workplace. Hazards related to chemicals used in the workplace are defined within the Workplace Hazardous Materials Information System (WHMIS). The Government of Canada is currently working with the provinces and territories to explore ways to enhance the protection of workers from exposure to chemicals by integrating and leveraging the information, tools, and/or technical expertise of the Chemicals Management Plan and Health Canada’s Workplace Hazardous Products Program.

New information and data

Comment summary 2: Additional information on import quantities and product concentrations was provided by the stakeholder for consideration.

Response 2: Additional information submitted was considered. The final Screening Assessment was reviewed in light of the new information; however, no changes to the report were made as the new information did not result in a change to the health risks or to exposure to members of the general population or to the environment.

Comment summary 3: Additional information on the release of Bisphenol A from BADGE or DGEBA from polymers and of unreacted isocyanates groups from the polyurethane 33 polymers was provided for consideration during the development of the final screening assessment.

It is suggested that additional research is required on the migration of substances from DGEBA-containing food packaging.

Furthermore, the stakeholder noted that PHMB could undergo slow and limited environmental transformation, and that all transformation products of PHMB should be considered.

Response 3: The Government of Canada

considers potential releases to the Canadian environment from disposal activities. The ecological risk of Polyurethane 33, DGEBA, and PHMB was considered in the Second phase of polymer rapid screening (ECCC HC 2018). As a risk-based approach, the screening assessment considered both hazard and exposure.

The scope of this screening assessment does not include evaluation of the chemicals used in polymer production, except with respect to their impact on the composition of, or residual presence in, the final polymer, which is being assessed.

Residual starting materials and degradation products can be considered when information is available; however, the presence of unreacted monomers in the final end use products is expected to be low as a result of purification steps. The low presence of unreacted monomers, in combination with the expected low exposure to the general population results in a low health risk. in addition, exposure of the general population to products made with the polymer results in low risk as it is trapped within a hardened matrix.

Polyurethane 33 was identified as having low environmental exposure potential and was characterized as having a low potential for ecological risk. It is unlikely that this substance is resulting in concerns for the environment in Canada. In addition, the current assessment found that Polyurethane 33 has high molecular weight, and meets the low concern polymer criteria. These indicate that Polyurethane 33 is stable and is not susceptible to significant environmental degradation, and release of isocyanate monomers are not expected.

For DGEBA resins, it is noted in this screening assessment that residual monomers are not expected to remain, as the resin undergoes purification to remove impurities. In the case of cured DGEBA resins, these polymers are anticipated to be stable. Thus, release of reacted Bisphenol-A from cured polymers is not expected. For PHMB, it is noted that environmental transformation would be slow and limited. As such, the degradation products were not given additional consideration.

The Food and Drugs Act and Regulations (Section B.23.001) addresses the potential transfer of harmful chemicals to foods. Any type of material, whether it is in the form of a finished product such as a laminated film, a container, or a formulated product such as a plastic resin, may be submitted to the Health Products and Food Branch (HPFB) for a pre-market assessment of chemical safety and subsequent issuance of an advisory opinion on their acceptability.

Comment summary 4: Toxicological information on BADGE or DGEBA, PHMB and Polyurethane 33 were provided.

Response 4: Similar toxicological information was considered during development of the draft screening assessment. The current assessment focuses on exposure to the polymer and not the chemical constituents of the polymer. Exposure to uncured polymers or residual monomers is considered to be low as a result of purification steps during polymer manufacture and because exposure of the general population is through products, which results in low exposure potential.

PHMB is considered to pose a health risk via inhalation and dermal sensitization and risk management measures are recommended.

Risk Management

Comment summary 5: Clarification was requested with respect to the specific PHMB uses that will not be subject to SNAc or other risk management provisions, so that ongoing safe uses are not unduly stigmatized. It was suggested that the Schedule I listing identify uses of concern.

Response 5: The Government of Canada’s proposed risk management activities will consider all uses currently in commerce and any potential uses of concern when developing the SNAc Notice of Intent. The SNAc provisions would be applied to products from which the substance is proposed or intended to be diffused or to be released as a vapour, mist or aerosol.  Stakeholders are asked to provide comments on the proposals outlined in the risk management approach document, and will have another opportunity to comment at the time of publication of a SNAc Notice of Intent, if this risk management action is pursued.

Listings to Schedule I of CEPA identify the substance only; they do not specify uses of concern.

Comments summary 6: Risk management measures are recommended to be applied to the use and disposal of PHMB and the disposal of polyurethane 33.

Response 6: The Government of Canada selects the most appropriate tools to manage the risks related to a substance. Selection is made using a thorough and consistent approach that takes into consideration information in the screening assessment and other sources, including stakeholder input. Risk management activities generally focus on the sources of exposure identified as being of concern in the screening assessment. In the case of PHMB, risk management actions are proposed to reduce dermal and inhalation exposure from cosmetics, and to prevent potential future exposures from products available to consumers from which the substance is proposed or intended to be diffused or to be released as a vapour, mist or aerosol.