4-Methylbenzylidene Camphor
4-Methylbenzylidene Camphor (also known as Enzacamene) is a chemical sunscreen agent that absorbs UVB radiation in the 290–320 nm range, with peak absorbance at 301 nm. It is an oil-soluble powder that is slightly photo-unstable, losing 10% of its protective capacity after 65 minutes and 50% after 345 minutes of exposure. Despite its own photo-instability, it can help stabilize avobenzone, a notoriously unstable UVA filter. It is not approved for use in the US or Japan, and has been banned in the EU starting in 2026, though it remains approved in Australia at up to 4%.
Provides UVB protection (290–320 nm) and can help stabilize the UVA filter avobenzone in sunscreen formulations. Its UV-absorbing function is well-documented in vitro.
Absorbs systemically through the skin and has demonstrated estrogenic activity in rat studies, raising potential endocrine-disruption concerns (though human relevance is uncertain). Currently being phased out globally: banned in the EU from 2026, not approved in the US or Japan. Slightly photo-unstable with prolonged sun exposure.
