The risks posed by a substance are determined by both its hazardous properties (potential to cause adverse human health or ecological effects) and the amount or extent of exposure to people or the environment.
When needed, the Government implements risk management measures under CEPA 1999 and other federal acts to help prevent or reduce potential harm.
The Government concluded that PHMB may be harmful to human health but not to the environment.
Risk management actions are proposed to help reduce exposure to PHMB from cosmetics and other products available to consumers, in particular, where there is risk of inhalation.
The other 3 substances in this group were concluded to be not harmful to human health or the environment at levels of exposure considered in the assessment.
These substances were previously evaluated under the second phase of polymer rapid screening and they were identified as requiring further assessment for potential human health risks. In accordance with the polymer rapid screening assessment, the potential for DGEBA-DA resin, PHMB, soya alkyd resin, and polyurethane-33 to cause harm to human health was further evaluated.
DGEBA-DA resin and PHMB do not occur naturally in the environment.
According to information gathered by the Government, DGEBA-DA resin is used in Canada as a binder, sealant and reactive component in coating, automotive, and adhesive industries. Soya alkyd resin and polyurethane-33 are used as ingredients in coatings such as paint. PHMB is used globally as a preservative or antimicrobial agent in cosmetics, natural health products, non-prescription drugs, pesticides, fabric softeners, contact lens solutions, and hand washes (including hand sanitizers).
Human and ecological exposures
DGEBA-DA resin was determined to have limited exposure to Canadians since its components are manufactured to react completely to form part of a stable polymer matrix.
Canadians may be exposed to PHMB from a number of products, including non-prescription drugs, natural health products, cosmetics, and other products available for consumers as well as from food.
As soya alkyd resin and polyurethane-33 met the criteria describing polymers of low concern of the New SubstancesNotification Regulations (Chemicals and Polymers), detailed exposures to Canadians were not described.
The potential for ecological exposure was evaluated under the second phase of polymer rapid screening. Available information indicated that the substances in the Other Polymers Group have low environmental exposure potential.
Key health and ecological effects (hazard)
Critical effects identified for characterizing the risk to human health for DGEBA-DA resin were effects on the prostate and skin sensitization.
For PHMB, the critical effect identified for characterizing the risk to human health was the potential for adverse respiratory effects, including inflammation of the respiratory tract. PHMB may also cause irritation to the eyes and skin and was found to be a skin sensitizer.
As soya alkyd resin and polyurethane-33 met the criteria for polymers of low concern, health hazards were not described.
The potential for ecological harm was evaluated under the second phase of polymer rapid screening. No ecological concerns were identified for DGEBA-DA resin and soya alkyd resin. Polyurethane-33 was classified as having moderate ecological hazard potential, and PHMB (CAS RNs 32289-58-0 and 27083-27-8) was classified as having high ecological hazard potential according to information considered in the second phase of polymer rapid screening.
Consideration of subpopulations who may be more susceptible or highly exposed
There are groups of individuals within the Canadian population who, due to greater susceptibility or greater exposure, may be more vulnerable to experiencing adverse health effects from exposure to substances.
Certain subpopulations are routinely considered throughout the screening assessment process, such as infants, children, and people of reproductive age. For instance, age-specific exposures are routinely estimated, and developmental and reproductive toxicity studies are evaluated for potential adverse health effects. These subpopulations were taken into account in the risk assessment outcomes for certain substances in the Other Polymers Group.
Risk assessment outcomes
Based upon available information, the risk to human health from DGEBA-DA resin, soya alkyd resin, and polyurethane-33 is low.
Based upon a comparison of levels to which Canadians may be exposed to PHMB through contact with the skin and inhalation, and levels associated with critical health effects, it was determined that this substance may pose a risk to human health.
Considering all information presented, it was determined that there is low risk of harm to the environment from the substances in the Other Polymers Group.
Screening assessment conclusions
The Government concluded that PHMB may be harmful to human health when there is risk of inhalation and that there is a risk of dermal sensitization. It was also concluded that the other 3 substances are not harmful to human health.
The Government also concluded that the 4 substances in the Other Polymers Group are not entering the environment at concentrations that are harmful.
It was also concluded that PHMB meets the persistence criteria but not the bioaccumulation criteria as set out in the Persistence and Bioaccumulation Regulations of CEPA 1999.
Preventive actions and risk reduction
The Government intends to add PHMB to Schedule 1 to CEPA 1999, also called the List of Toxic Substances. Adding a substance to the list does not restrict its use, manufacture or import. Rather, it enables the Government to take risk management actions under CEPA 1999.
Publication of the risk management approach aims to inform stakeholders of proposed risk management actions and continue discussion about their development. The risk management approach indicates that the Government is considering the following actions to address human health concerns:
For cosmetics: taking measures to reduce exposures of the general population to PHMB from dermally applied cosmetic products, including topical and spray applications, by describing PHMB as a prohibited or restricted ingredient on the Health Canada Cosmetic Ingredient Hotlist. The Hotlist is used to communicate that certain substances may not comply with requirements of the Food and Drugs Act or provisions of the Cosmetic Regulations.
For other products available to consumers: applying Significant New Activity (SNAc) provisions under CEPA 1999. The SNAc provisions would require anyone proposing specified new activities related to PHMB to notify the Government and provide information so that the new activities are assessed for potential risks to human health and the environment before being undertaken. The SNAc provisions would be applied to products from which the substance is proposed or intended to be diffused in the air or to be released as a vapour, mist or aerosol. PHMB-containing products may be subject to registration requirements under the Pest Control Products Act.
Risk management actions may evolve through consideration of assessments and risk management actions published for other substances. This is to ensure effective, coordinated, and consistent risk management decision-making.
Use the Substances Search tool to find substances that are referenced in certain legislative or regulatory instruments or on Government of Canada websites.
Related resources
The substances in this group may be found in products available to consumers. Canadians should follow any safety warnings and directions related to the products they use and dispose of products responsibly.
Cosmetics must include a list of all ingredients on the product label using the International Nomenclature of Cosmetic Ingredients (INCI) system. The INCI name for PHMB is polyaminopropyl biguanide.
