Ensulizole: is it allowed in sunscreen? Korea vs US vs EU
Ensulizole (Phenylbenzimidazole Sulfonic Acid, PBSA) is an organic (chemical) UV filter covering UVB. It is allowed in Korean sunscreens (up to 4%). In the United States it is an approved OTC sunscreen active ingredient (up to 4%). In the EU it is allowed (up to 8%).
| INCI name | Phenylbenzimidazole Sulfonic Acid |
|---|---|
| Also known as | Phenylbenzimidazole Sulfonic Acid, PBSA |
| Name on Korean labels | 페닐벤즈이미다졸설포닉애씨드 |
| CAS number | 27503-81-7 |
| Protects against | UVB |
Where Ensulizole is allowed — country by country
| Region | Status | Official conditions |
|---|---|---|
| South Korea | ✓ up to 4% | |
| United States | ✓ up to 4% | |
| European Union | ✓ up to 8% | Maximum concentration in ready for use preparation : 8%(as acid) |
| Japan | ✓ up to 3% | |
| China | ✓ up to 8% | |
| Canada | ✓ up to 4% | Maximum Concentration Permitted : ≤ 4% |
| ASEAN | ✓ up to 8% | Maximum authorised concentration in the finished cosmetic product : 8% expressed as acid |
| Taiwan | ✓ up to 8% | |
| Brazil | ✓ up to 8% | Maximum concentration permitted at final product : 8% (expresado como ácido) |
| Argentina | ✓ up to 8% | Maximum concentration permitted at final product : 8% (expresado como ácido) |
✓ = allowed as a UV filter, with the maximum concentration in the finished product. * = the limit depends on product type (see the filter page). ✗ = banned. — = no entry in the official list compiled by Korea's MFDS (for the US this means it is not an approved sunscreen active; for other regions, check the regulator's own list).
Source: Korea MFDS "Cosmetic ingredients with use restrictions" (international regulations compiled by MFDS, data.go.kr), refreshed weekly; US changes checked against FDA orders (October 2026). Regulations change — confirm with the regulator before formulating or importing.
Checking a Korean sunscreen
Korean ingredient lists use the Korean name above (페닐벤즈이미다졸설포닉애씨드). To check that a Korean sunscreen is officially registered with its SPF/PA, search the MFDS registry.