Health

Years of studies have confirmed the safety of linear and cyclic siloxanes for human health when used as intended. We have put together some of the most recent and relevant research, divided into three categories: Toxicology data, Absorption, Distribution, Metabolism, and Excretion (ADME) assessment, Relevance for human health.

Toxicology data

Toxicological research aims to assess the potential adverse effects of chemicals on human health. The field of toxicology considers variables, such as dose and type of exposure, susceptibility to the chemical, age, health status of the person, and more.

A wealth of data exists to assess the toxicity of linear and cyclic siloxanes. Commonly, the method for assessing toxicity is through studies in a laboratory. If a risk is identified, these studies are then analysed for their relevance to human health.

ADME assessment

Understanding the routes of exposure and the fate of the substances after they have entered the human body is a crucial component of assessing their potential adverse effects. This is commonly done using the concept of ADME, or how a substance is Absorbed, Distributed, Metabolised, or Eliminated in the human body.

A series of new assessments of octamethylcyclotetrasiloxane (D4) in Toxicology Letters, and recent weight-of-evidence studies bring forward compelling evidence that D4 does not present a risk to human health. These recent assessments are consistent with a large body of peer-reviewed publications supporting the safety of D4 and independent government assessments in Australia and Canada concluding that the use of D4 does not pose a danger to human health.

Relevance for human health

Animal and laboratory studies can give an indication of the potential adverse effects of chemicals. It is important to consider, however, the relevance of the data to human health. This accounts for the presence of modes of action specific to animals.

To understand if studies performed in labs are relevant for human health, it is necessary to look at the mode of action, that is, the biological event leading to an adverse effect. Once the hazard has been established, the doses/concentrations used in the animal studies are compared with potential human exposure to assess the risk. Animal studies are conducted at high doses/concentrations which may never be encountered in real situations during production or use.