TMSS - information sheet

Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, hydrolysis products with silica
CAS Registry Number 68909-20-6

Publications summarized:

Final Screening Assessment for Silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, hydrolysis products with silica (published May 14, 2022). Public comments received on the draft screening assessment were considered and summary of the comments with Government responses was published.
Associated notice: Canada Gazette, Part I, Vol. 156, No. 20 – May 14, 2022

The Government of Canada conducts risk assessments of substances under the Canadian Environmental Protection Act, 1999 (CEPA 1999) to determine whether they present or may present a risk to human health or to the environment.
- The risks posed by a substance are determined by both its hazardous properties (potential to cause adverse human health or ecological effects) and the amount or extent of exposure to people or the environment.
The ecological hazard and exposure potentials of this substance were classified using the Ecological Risk Classification of Organic Substances (ERC) Approach.
The Government concluded that TMSS is not harmful to human health or to the environment at levels of exposure considered in the assessment.

The screening assessment focused on silanamine, 1,1,1-trimethyl-N-(trimethylsilyl)-, hydrolysis products with silica. This substance may also be referred to as TMSS. It was assessed as part of the third phase of the Chemicals Management Plan (CMP).
TMSS is a substance of Unknown or Variable Composition, Complex Reaction Products, or Biological Materials (UVCBs). It does not naturally occur in the environment.
According to information gathered by the Government, this substance is used in Canada in the manufacture of cosmetics, natural health products and non-prescription drugs, multipurpose cement adhesives, paints, silicone rubbers, inks and toners, and medical devices. TMSS may also be present in pest control products. This substance is used in industrial applications in the automotive, electrical and electronic sectors.
The substance may be used as a component in the manufacture of food packaging materials; however, consumer exposure from this use is expected to be negligible. It may also be used as a component of an incidental additive (lubricant) used in food processing establishments with no significant potential exposure anticipated.

Canadians may be exposed to TMSS through the use of products available to consumers, with cosmetics (including dry hair shampoo and facial blush) as the main sources of exposure.
According to the information considered under the ERC Approach, TMSS was identified as having a high ecological exposure potential based on its large annual import quantity and long overall persistence in the environment.

There were limited health effects (hazard) data for TMSS; therefore, a comparative approach using similar chemicals, called read-across, was also used to assess potential health effects. Lung effects were identified as the critical effect for characterizing the risk to human health from repeated inhalation of TMSS.
According to the information considered under the ERC Approach, TMSS was identified as having a low ecological hazard potential.

There are groups of individuals within the Canadian population who, due to greater susceptibility or greater exposure, may be more likely to experience adverse health effects from exposure to substances.
Certain subpopulations are routinely considered throughout the screening assessment process, such as infants, children, and people of reproductive age. For instance, age-specific exposure estimates are routinely derived and developmental and reproductive toxicity studies are evaluated for potential adverse health effects. For TMSS, these subpopulations with potential for higher exposure and those who may be more susceptible were taken into account in the risk assessment outcomes.

Using a comparison of levels to which Canadians may be exposed to TMSS, and levels associated with critical effects, it was determined that the risk to human health is low.
According to information considered under the ERC Approach, TMSS is unlikely to be causing ecological harm.

The Government concluded that TMSS is not harmful to human health at levels of exposure considered in the assessment, and is not entering the environment at levels that are harmful.

TMSS 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.
Use the Substances Search tool to find substances that are referenced in certain legislative or regulatory instruments or on Government of Canada websites.
The screening assessment focused on potential risks from exposure of the general population of Canada, rather than occupational exposure. Hazards related to chemicals used in the workplace are defined within the Workplace Hazardous Materials Information System. For information concerning workplace health and safety and what steps to take in the workplace, Canadians should consult their employer and/or the Occupational Health and Safety Regulator in their jurisdiction.