Dea-styrene/acrylates/dvb copolymer is a chemical compound, a styrene by-product.

Significant substances used in the production method:
styrene, divinylbenzene, acrylic acid, methacrylic acid.

Safety
Styrene is a fat-soluble organic molecule obtained from the Friedel-Crafts reaction between benzene and ethylene. It is a residual monomer that can be absorbed through the skin. It can cause neurotoxic effects.
Kraeling, M. E., & Bronaugh, R. L. (2005). In vitro percutaneous absorption of acrylamide and styrene from cosmetic vehicles through fuzzy rat and human skin. Cutaneous and Ocular Toxicology, 24(1), 65-79.

Some of the scientific literature warns of the possible danger of DEA, while a 1998 study by the National Toxicology Program (NTP) did not establish a link between DEA and cancer risk in humans.
The most relevant studies on this ingredient have been selected with a summary of their contents: https://www.tiiips.com/m/tiiips/home?action=listReviews&reviewID=9682&oID=1929

What it is used for and where
Cosmetics

Opacifying agent. It is useful into formulations that may be translucent or transparent to make them opaque and less permeable to light.
Synonyms:

CAS: