Organic Peroxides Group - information sheet

Hydroperoxide, 1-methyl-1-phenylethyl (Cumene hydroperoxide; CHP)
CAS Registry Number 80-15-9

Peroxide, bis(1-methyl-1-phenylethyl) (Dicumyl peroxide; DCUP)
CAS Registry Number 80-43-3

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  • The Government of Canada conducted a science-based evaluation, called a screening assessment, of 2 substances in the Organic Peroxides Group to address the potential for harm to Canadians and to the environment.
  • Under the Canadian Environmental Protection Act, 1999 (CEPA 1999), the risk posed by a substance is determined by considering both its hazardous properties (its potential to cause adverse human health or ecological effects) and the amount of exposure there is to people or the environment. A substance may have hazardous properties; however, the risk to human health or to the environment may be low depending upon the level of exposure.
  • The ecological hazard and exposure potentials of these 2 substances were classified using the Ecological Risk Classification of Organic Substances Approach.
  • Although dicumyl peroxide (DCUP) may have potential effects on the human reproductive system, it was determined that the risk to Canadians and the environment is low at current levels of exposure. The risk to human health and the environment from cumene hydroperoxide (CHP) is also low. Therefore, it is proposed to conclude that DCUP and CHP are not harmful to human health or the environment.

About these substances

  • This screening assessment focuses on 2 of the 6 substances referred to collectively as the Organic Peroxides Group. The substances addressed in this screening assessment are hydroperoxide, 1-methyl-1-phenylethyl (commonly referred to as cumene hydroperoxide or CHP) and peroxide, bis(1-methyl-1-phenylethyl) (commonly referred to as dicumyl peroxide or DCUP). They were assessed as part of the third phase of the Chemicals Management Plan (CMP).
  • The other 4 substances in the Organic Peroxides Group were determined to be of low concern to both human health and the environment, through other approaches. Conclusions for CAS RNs 133-14-2, 614-45-9, 3006-86-8 and 3851-87-4 are provided in the Substances Identified as Being of Low Concern using the Ecological Risk Classification of Organic Substances and the Threshold of Toxicological Concern (TTC)-based Approach for Certain Substances Screening Assessment .
  • The Government gathers information on substances, including details on their commercial status in Canada, to support risk assessment and risk management of substances under the CMP.
  • In Canada, CHP and DCUP are used as industrial processing agents and they are present in negligible quantities in finished materials after processing.
  • CHP is used in products available to consumers, such as adhesives and sealants, building and construction materials, and paints and coatings.
  • DCUP is used in commercial products, such as building and construction materials, plastic and rubber materials, as well as in products used in transportation.

Exposure of Canadians and the environment

  • Exposure of Canadians to CHP and DCUP from the environment (for example, air, water or soil) and food is either negligible or not expected.
  • Canadians may be exposed to low quantities of CHP from the use of adhesive products available to consumers.
  • Canadian exposure to DCUP from commercial products and products available to consumers is not expected.
  • For the ecological assessment, CHP was identified as having a low ecological exposure potential. DCUP, however, was identified as having a moderate ecological exposure based on its persistence and reported use quantities.

Key health and ecological effects (hazard)

  • To identify effects of concern for human health, international reports of data on these substances were reviewed. These included reviews by the Organisation for Economic Co-operation and Development (OECD) and by the Australian Government Department of Health (AGDH).
  • On the basis of these existing international assessments, general toxicity through oral, inhalation and dermal routes of exposure were identified for CHP.
  • A harmonized classification of reproductive toxicity for DCUP was proposed by the Norwegian Environment Agency (ECHA 2017) based on a recent developmental toxicity study. Therefore, reproductive effects were considered to be the important or “critical” effects for DCUP.
  • For the ecological assessment, CHP and DCUP were identified as having a low ecological hazard potential.

Risk assessment outcomes

  • The OECD assessments were used to inform the human health effects characterization of this group of substances. These assessments undergo rigorous review (including peer-review) and endorsement by international governmental authorities. Health Canada and Environment and Climate Change Canada are active participants in these processes, and consider these assessments reliable.
  • Based upon a comparison of levels to which Canadians may be exposed to CHP and levels associated with no adverse health effects, the risk to human health from this substance is considered to be low.
  • Exposure of Canadians to DCUP is not expected and therefore the risk to human health is also low for this substance.
  • The Ecological Risk Classification of Organic Substances Approach characterized these 2 substances as posing a low risk of harm to the environment.
  • The Government of Canada published the Draft Screening Assessment for the Organic Peroxides Group on April 28, 2018. This publication has a 60-day public comment period ending on June 27, 2018.

Proposed screening assessment conclusions

  • As a result of this assessment, the Government is proposing that CHP and DCUP are not harmful to human health at current levels of exposure. 
  • The Government is also proposing that CHP and DCUP are not entering the environment at levels that are harmful to the environment.

Preventive actions and reducing risks

  • Although DCUP is not considered to be harmful to human health or the environment at current levels of exposure, this substance is considered to have a health effect of concern based on its potential reproductive effects. Therefore, there may be a concern for human health if exposures were to increase. 
  • Follow-up activities to track changes in exposure and/or commercial use patterns for DCUP are currently under consideration.
  • Stakeholders are encouraged to provide any information pertaining to this substance that may help inform the choice of follow-up activity, during the 60-day public comment period on the assessment. This could include information on new or planned import, manufacture or use of the substance.

Important to know

  • CHP can be found in products available to consumers. Canadians should follow any safety warnings and directions on product labels and dispose of products responsibly.
  • Canadians who may be exposed to these 2 substances in the workplace should consult with their employer and an occupational health and safety (OHS) representative about safe handling practices, applicable laws, and requirements under OHS legislation and the Workplace Hazardous Materials Information System (WHMIS).
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