Mastocarpus Stellatus
Reviewed by Kate · Last updated 18 Aug 2026
Also known as: carrageenan moss, false Irish moss
Mastocarpus stellatus is an algae is known as carrageenan moss
Addresses
Antioxidant
EWG Safety Score
2
Low
What Is Mastocarpus Stellatus?
Mastocarpus stellatus is an algae is known as carrageenan moss or false Irish moss. It is a type of red seaweed. In skin care, it has antioxidant properties.
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