The risks posed by a substance are determined both by its hazardous properties (potential to cause adverse human health or ecological effects) and the amount or extent of exposure to people and 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 is proposing that 1-bromopropane may be harmful to human health due to potential exposure from products available to consumers and its association with developmental effects. 1-Bromopropane is also associated with neurotoxicity and potential carcinogenicity.
The Government is proposing regulatory and/or non-regulatory actions to help reduce potential human exposures to 1-bromopropane.
Some of the substances in the Alkyl Halides Group are associated with health effects, including developmental toxicity and cancer (chloroethane), changes to cells in the nasal cavity (bromoethane), and the potential to cause cancer (bromoethane).
None of the substances in this group are proposed to be harmful to the environment, at levels of exposure considered in the assessment.
About these substances
The summary of publications for the Alkyl Halides Group timeline includes details on the substance names and CAS Registry Numbers (RNs).
The 4 substances included in the Alkyl Halides Group are human-made. Bromoethane and 1-bromopropane are also naturally occurring.
According to information gathered by the Government, the 4 substances in the Alkyl Halides Group are mainly used in Canada in products available to consumers, such as liquid or aerosol cleaners or degreasers, aerosol starting fluids (engine starting aid), air conditioning flush, silicone mold release spray, and spray foam insulation.
Human and ecological exposures
The screening assessment indicates that Canadians may be exposed to the 4 substances included in the Alkyl Halides Group through environmental sources, such as indoor and ambient air.
The main source of exposure to bromoethane is from indoor and ambient air. Bromoethane is not anticipated to be found in products available to consumers.
The main source of exposure to chloroethane is from indoor and ambient air, and the use of starting fluid spray.
The main source of exposure to trans-1,2-dichloroethane is from indoor and ambient air and the use of textile spot cleaners.
1-Bromopropane exposure is expected from indoor air, and the use of silicone mold release spray, electronic cleaner spray and automotive air conditioning flush.
According to the information considered under the ERC Approach, bromoethane and 1-bromopropane were identified as having low ecological exposure potential, while chloroethane and trans-1,2-dichloroethane were classified as having a high ecological exposure potential based on a long half-life in air and a large annual import quantity.
Bromoethane has been classified by the European Chemicals Agency (ECHA) as "suspected of causing cancer", in the Global Harmonized System (GHS). Changes to cells in the nasal cavity, and the potential to cause cancer were considered to be critical effects considered in the risk assessment.
Chloroethane has been classified by ECHA as "suspected of causing cancer" in the GHS. The critical effect identified to characterize risk to human health for chloroethane was developmental toxicity and cancer.
The critical effect identified to characterize the risk to human health for trans-1,2-chloroethane was immunotoxicity.
1-Bromopropane has been classified by the International Agency for Research on Cancer (IARC) as "possibly carcinogenic". This substance was also classified by ECHA as a "presumed reproductive toxicant" in the GHS. The critical effects identified for characterizing risk to 1-bromopropane include developmental effects, neurotoxicity and cancer.
According to information considered under the ERC Approach, trans-1,2-dichloroethane was identified as having a low ecological hazard potential while bromoethane, chloroethane and 1-bromopropane were identified as having moderate ecological hazard potentials based on increased level of ecotoxicity.
Risk assessment outcomes
Based upon a comparison of levels to which Canadians may be exposed to 1-bromopropane from certain products available to consumers, and levels associated with health effects, it was determined that this substance may pose a risk to human health.
It was determined that the risk to human health from bromoethane, chloroethane and trans-1,2-chloroethane is low. This was based upon a comparison of levels to which Canadians may be exposed to each of these substances, and levels associated with health effects.
Based upon the outcome of the ERC Approach, all 4 substances assessed are considered unlikely to be causing ecological harm.
Proposed screening assessment conclusions
The Government is proposing that 1-bromopropane may be harmful to human health at levels of exposure considered in the assessment; however, it is proposing that the other 3 substances are not harmful to human health at levels of exposure considered in the assessment.
The Government is also proposing that all 4 substances are not entering the environment at concentrations that are harmful.
If the proposed conclusion is confirmed in the final screening assessment, the Government will consider adding 1-bromopropane to Schedule 1 of 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 scope aims to inform stakeholders of proposed risk management options and initiate discussion about their development. The Government will consider the following actions to help address human health concerns:
Regulatory and/or non-regulatory measures to help reduce inhalation exposures to 1-bromopropane contained in certain products available to consumers such as automotive air conditioning flush, silicone mold release spray and electronics cleaner spray.
Information is being sought by the Government to inform risk management decision-making. Details can be found in the risk management scope, including where to send information during the public comment period, ending May 4, 2022.
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.
Although a risk to human health or the environment has not been identified at current levels of exposure, there may be a concern if exposure to bromoethane and chloroethane were to increase. As a result, these substances may be considered in future initiatives to track their commercial status or identify new uses.
Use the Substances Search tool to find substances that are referenced in certain legislative or regulatory instruments or on Government of Canada websites.
Substances within the Alkyl Halides Group may be found in products available to consumers. Canadians should follow any safety warnings and directions related to the product and dispose of products responsibly.