4-Vinylyclohexene (4-VCH) - information sheet

Cyclohexene, 4-ethenyl-
CAS Registry Number 100-40-3

Overview

The Government of Canada conducted a science-based evaluation, called a screening assessment, of 4-VCH, 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.
- More information on assessing risk can be found in the Overview of Risk Assessment and related fact sheets, particularly on Types of Risk Assessment Documents and the Risk Assessment Toolbox.
The ecological hazard and exposure potentials of 4-VCH were classified using the Ecological Risk Classification of Organic Substances Approach.
The substance 4-VCH may have effects of concern for human health; however, the risk to human health is low at current levels of exposure, and it is considered to have a low ecological hazard potential. Therefore, it is concluded that this substance is not harmful to human health or to the environment.

This screening assessment focuses on the substance cyclohexene, 4-ethenyl-, also referred to as 4-vinylcyclohexene (4-VCH).
This substance was assessed as part of the third phase of the Chemicals Management Plan (CMP).
Industry data collected by the Government indicates that 4-VCH was imported into, but not manufactured in Canada at quantities above 100 kilograms. More information on the data collected by the Government can be found in the specific information gathering initiatives.
4-VCH does not occur naturally in the environment. It is primarily used in the manufacture of products, such as flame retardants, plastic and rubber materials, and adhesives.

Canadians may be exposed to 4-VCH primarily from the off-gassing of a limited number of new manufactured items, such as new carpets and laminated building materials, but exposures would be limited, occurring only over a short period of time.
4-VCH was identified as having low ecological exposure potential.

To identify effects of concern for human health, international reports of data on 4-VCH were reviewed. These reviews were used to inform the health effects characterization in this screening assessment.
Available information indicates that this substance may be carcinogenic (able to cause cancer). This was considered to be the important or "critical" effect used for characterizing the risk to human health in the assessment of this substance.
4-VCH was identified as having a low ecological hazard potential.

4-VCH has been assessed by the European Chemicals Agency (ECHA) and by the International Agency for Research on Cancer (IARC). These assessments undergo extensive 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.
On the basis of information presented in this screening assessment, the risk to human health from 4-VCH is considered to be low.
The Ecological Risk Classification of Organic Substances Approach characterized 4-VCH as posing a low risk of harm to organisms and the environment.
The Government of Canada published the Final Screening Assessment for 4-VCH on March 10, 2018.

As a result of this assessment, the Government concluded that 4-VCH is not harmful to human health at current levels of exposure.
The Government also concluded that 4-VCH is not entering the environment at levels that are harmful to the environment.

Although 4-VCH is not considered to be harmful to human health at current levels of exposure, this substance is considered to have a health effect of concern based on its potential carcinogenicity (ability to cause cancer). Therefore, there may be a concern for human health if exposures to this substance were to increase.
For this reason, the Government may gather information to track changes in exposure and/or commercial use patterns for 4-VCH, which may involve including the substance in future information gathering initiatives, such as a mandatory survey under section 71 of CEPA 1999.

Canadians who may be exposed to 4-VCH in the workplace should consult with their employer and an occupational health and safety (OHS) representative on safe handling practices, applicable laws, and requirements under OHS legislation and the Workplace Hazardous Materials Information System (WHMIS).