Ingredient
Trimethylsiloxysilicate
What is Trimethylsiloxysilicate?
Trimethylsiloxysilicate is a silicone-based polymer primarily used in cosmetics and personal care products. It is synthesized through the reaction of siloxane compounds to create a stable, film-forming agent.
This compound is commonly used for its ability to form a flexible, long-lasting film on the skin's surface, which helps the product adhere better and resist water. It is valued in makeup and sunscreens for providing improved wear and durability. While generally considered safe for topical use, some concerns exist regarding its environmental impact, as silicones can accumulate in ecosystems.
When you see it on a label, it is often included to enhance product performance, especially in waterproof and long-wear formulations.
Commonly found in: sunscreen, foundation, lipstick, mascara, eyeshadow
What to watch
- Silicones like trimethylsiloxysilicate can persist in the environment, potentially affecting ecosystems.
Benefits
- Provides long-lasting, water-resistant properties in cosmetics and sunscreens.
The FDA recognizes it as a safe ingredient in cosmetics, with no specific restrictions.
Research generally supports its safety for topical use, but environmental persistence is a growing concern.
As a synthetic compound, it is not derived from animal sources and is typically considered vegan.
Sources: Status of Siloxanes in Cosmetics
Scout's take
Silicone resin used for waterproofing. Bioaccumulative and persistent in the environment. Can trap other chemicals against the skin and impede natural moisture regulation.
The case against
There are minimal risks associated with this ingredient, though it may cause irritation in sensitive individuals.
from the analysis of Sun Bum Signature SPF 30 LotionThe case for
It enhances the water resistance and durability of the sunscreen.
from the analysis of Sun Bum Signature SPF 30 LotionMore from Scout's analyses
Trimethylsiloxysilicate is a silicone compound that can create a barrier on the skin. While it provides a smooth application, it may contribute to skin irritation and has a risk of bioaccumulation.
from the analysis of Rare Beauty by Selena Gomez Stay Vulnerable All-Day Waterproof EyelinerTrimethylsiloxysilicate is used as a film-forming agent in cosmetics. It helps to create a water-resistant barrier on the skin. It is generally considered safe for use in cosmetics.
from the analysis of Sun Bum Signature SPF 30 LotionSilicone film-former. Water-resistant film but not biodegradable.
from the analysis of Blue Lizard Sensitive Mineral Sunscreen SPF 50Found in 5 products
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