Macrocyclic Lactones and Ketones, Ionones and Cyclohexanone Group – information sheet

Overview

The Government of Canada conducted a science-based evaluation, called a screening assessment, to address the potential for harm to Canadians and to the environment from 11 substances in the Macrocyclic Lactones and Ketones, Ionones and Cyclohexanone Group [previously identified as the Musks (macro/poly cyclic) Group].
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 these 11 substances were classified using the Ecological Risk Classification of Organic Substances Approach.
As a result of the screening assessment, the Government concluded that the substances in the Macrocyclic Lactones and Ketones, Ionones and Cyclohexanone Group are not harmful to human health or to the environment.

This screening assessment focuses on 11 of 13 substances referred to collectively as the Macrocyclic Lactones and Ketones, Ionones and Cyclohexanone Group. The substances addressed are exaltolide, hexadecanolide, exaltone, muskone/muscone, civetone, hexadecenlactone/ambrettolide, isoambrettolide, musk amberol/ambrettone, irone, 1-methyl-α-ionone and cyclohexanone. They were assessed as part of the third phase of the Chemicals Management Plan (CMP).
The other 2 substances in the Macrocyclic Lactones and Ketones, Ionones and Cyclohexanone Group (CAS RNs 8001-04-5 and 68140-48-7) were determined to be of low concern to both human health and the environment, through other approaches. Conclusions for these substances are provided in the Screening Assessment for 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.
According to information gathered by the Government, 4 of the 11 substances (exaltolide, muskone/muscone, civetone, and cyclohexanone) occur naturally in the environment.
Substances in this group are used mainly as fragrances or fragrance ingredients.
In Canada, these substances are also used in products available to consumers, including cosmetics (such as body lotion and eau de toilette), sunscreen, and do-it-yourself (DIY) products, such as wall paint.

Exposure of Canadians to these substances from the environment or food is considered minimal.
Canadians may be exposed to low levels of some of these substances from the use of certain cosmetics and DIY products.
According to information considered under the Ecological Risk Classification of Organic Substances Approach, these 11 substances were identified as having low ecological exposure potential.

On the basis of available information, no effects of concern for human health were identified for 8 of the 11 substances in this group.
For irone and 1-methyl-α-ionone, a comparative approach based on properties of similar chemicals, called read-across, was used for assessing potential health effects. Using this data, adverse effects on the kidneys observed in laboratory studies were considered to be the important or "critical" effects used for characterizing the risk to human health from exposure to these 2 substances.
For cyclohexanone, several international reports were reviewed, including one by the Organisation for Economic Co-operation and Development (OECD) Cooperative Chemicals Assessment Programme. On the basis of the OECD assessment, cyclohexanone showed low potential for adverse effects on human health through the oral and inhalation routes of exposure.
According to information considered under the Ecological Risk Classification of Organic Substances Approach, 9 of the 11 substances were identified as having a low ecological hazard potential while the other 2 substances (irone and 1-methyl-α-ionone) were identified as having a moderate ecological hazard potential. These hazard classifications were based on their moderate ecotoxicity and potential to cause adverse effects in the aquatic food webs due to their potential to accumulate in organisms.

Based upon a comparison of levels to which Canadians may be exposed to these 11 substances and levels associated with health effects, the risk to human health from these substances is considered to be low.
Based upon the outcome of the Ecological Risk Classification of Organic Substances Approach, these 11 substances are considered unlikely to cause ecological harm.
The Government of Canada published the Final Screening Assessment for Macrocyclic Lactones and Ketones, Ionones and Cyclohexanone Group on July 6, 2019.

As a result of the assessment, the Government concluded that these 11 substances are not harmful to human health at levels of exposure current at the time of the assessment.
The Government also concluded that these 11 substances are not entering the environment at levels that are harmful to the environment.

Substances in this group can be found in certain 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 any of these substances in the workplace can 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).