New substances: risk assessment summary, new substances notification 19602 and 21114

Official title: New Substances Notifications 19602 and 21114: 1,2-Ethanediol, 1,2-dibenzoate (Chemical Abstracts Service registry number 94-49-5)

Regulatory decisions

Under the provisions for Substances and Activities New to Canada in Part 5 of the Canadian Environmental Protection Act, 1999 (CEPA), and pursuant to section 83 of the Act, the Minister of the Environment and the Minister of Health have assessed information in respect of the substance, and determined that the substance is anticipated to enter the environment in a quantity or concentration or under conditions that constitute or may constitute a danger in Canada to human life or health.

In order to ensure that the substance does not cause harm to the Canadian environment or human health, its manufacture and import are authorized subject to conditions as described in:

• Ministerial Condition No. 19602 published in the Canada Gazette Part I, Vol. 152, No. 43 on October 27, 2018
• Ministerial Condition No. 21114 published in the Canada Gazette Part I, Vol. 156, No. 29 on July 16, 2022

Substance identity

The notified chemical is 1,2-ethanediol, 1,2-dibenzoate (Chemical Abstracts Service registry number^{Footnote 1} 94-49-5). 

Notified and potential uses

The substance is proposed to be imported into Canada in quantities greater than 10 000 kg/yr for the notified use in industrial applications. Potential uses may include industrial applications other than those notified, personal care products or food packaging.

Environmental fate and behaviour

Based on its physical and chemical properties, if the substance is released to the environment, it will tend to partition to soil and sediment. The substance is not expected to be persistent in these compartments based on its high ready biodegradability (>60% over 28 days). The substance is not expected to bioaccumulate based on its moderate octanol-water partition coefficient (log K_ow <5) and expected low bioaccumulation and bioconcentration factors (<250 L/kg).

Environmental risk assessment

Based on the available hazard information on the substance and surrogate data on structurally related chemicals, the substance is expected to have low to moderate acute toxicity in fish and aquatic invertebrates (median lethal concentration (LC₅₀), median effective concentration and median effective loading rate 1-100 mg/L; no adverse effects observed in saturated solutions), high chronic toxicity in fish (no-observed-effect-concentration (NOEC) <0.1 mg/L) and moderate chronic toxicity in aquatic invertebrates and algae (10% effective loading rate and 10% effective concentration 0.1-10 mg/L). Using the NOEC from the most sensitive organism (fish) and by applying an appropriate assessment factor of 4 to account for species sensitivity variation and mode of action, the predicted no-effect concentration (PNEC) was calculated to be in the range of 10-100 µg/L, which was used to estimate the ecological risk.

The notified and other potential activities in Canada were assessed to estimate the environmental exposure potential of the substance throughout its life cycle. Environmental exposure from the notified activities is expected to be mainly from industrial use from release of the substance resulting in a predicted environmental concentration (PEC) in the range of 0.001-0.01 µg/L. For potential activities such as manufacturing and use in other industrial applications, environmental exposure is expected to be mainly from release of the substance to water resulting in a PEC in the range of 1-10 µg/L and 0.1-1 µg/L, respectively.

Comparing the PECs with the PNEC, the ratio is less than 1. This, along with other lines of evidence including environmental fate, hazard and exposure, indicates that the substance is unlikely to cause ecological harm in Canada.

Human health risk assessment

Based on the available hazard information for the substance and surrogate data on structurally related chemicals, the substance has a low acute toxicity by the oral and dermal routes (median lethal dose >2000 mg/kg body weight). The substance is expected to have low acute toxicity by inhalation (LC₅₀ >5 mg/L/4hr). The substance has low subchronic toxicity following repeat oral doses in mammalian test animals (92-98 day no-observed-adverse-effect level (NOAEL) >100 mg/kg-bw/day). The substance has a low reproductive toxicity (NOAEL >1000 mg/kg-bw/day) and a moderate developmental toxicity (NOAEL >250-1000 mg/kg-bw/day) following repeat oral doses in mammalian test animals. The critical effect observed in the repeat oral dose mammalian studies indicates the potential for endocrine disruption; therefore, the overall human health concern is considered to be high. It is not a skin sensitizer (>10% estimated concentration required to produce a stimulation index of 3 (local lymph node assay)). It is not mutagenic in vitro or clastogenic in vitro or in vivo. Therefore, the substance is unlikely to cause genetic damage. The provisional tolerable daily intake (PTDI) was calculated to be in the range of 0.1-1 mg/kg-bw/day based on the NOAEL of the oral subchronic toxicity study with mammalian test animals.

When the notified substance is used in industrial applications, consumers may come into contact with end-use products containing the substance; however, direct exposure is not expected because the substance will be encapsulated within a stable matrix once the product is cured and will be unavailable for uptake. Indirect exposure of the general population from environmental media is not expected given the specialized industrial use of the substance, which results in little or no release to the environment.

Potential uses of the substance include personal care products, where direct exposure of the general population is conservatively estimated to be at levels in the range of 0.1-1 mg/kg-bw/day for adults by ingestion and 1-100 mg/kg-bw/day for adults and children by contact with the skin. Indirect exposure of the general population from environmental media such as drinking water is expected to be at levels which do not pose a concern, similar to that of the notified use.

Because the estimated human exposure when used as notified is less than the PTDI, meaning at levels that do not pose a concern, the substance is not likely to pose a significant health risk to the general population, and is therefore unlikely to be harmful to human health when used as notified.

However, based on the increased potential for direct oral and dermal exposure if used in personal care products combined with the high concern for endocrine disruption, the substance is anticipated to be harmful to human health.

Other considerations

A Ministerial Condition was imposed on a similar substance, 1,2-propanediol, 1,2-dibenzoate (Chemical Abstracts Services Registry Number 19224-26-1), published in the Canada Gazette Part I, Vol. 149, No. 42 on October 17, 2015.

Assessment conclusion

The substance is suspected to constitute a danger to human health according to the criteria under paragraph 64 (c), but is not suspected to have a harmful effect on the environment according to the criteria under paragraph 64(a) or (b) of the Act.

Due to the identified risk to human health related to the high concern for endocrine disruption, ministerial conditions were issued to restrict the manner in which the notifier may manufacture or import the substance with conditions on its use in order to mitigate these potential risks.

• Ministerial Condition No. 19602 was published in the Canada Gazette Part I, Vol. 152, No. 43 on October 27, 2018.
• Ministerial Condition No. 21114 was published in the Canada Gazette Part I, Vol. 156, No. 29 on July 16, 2022.

A conclusion under CEPA, on this substance, is not relevant to, nor does it preclude an assessment against the hazard criteria for Workplace Hazardous Materials Information System that are specified in the Controlled Products Regulations or Hazardous Products Regulations for products intended for the workplace.