<!-- Tris-Biphenyl Triazine (Tinosorb A2B): is it reef safe? -->
Source: https://reeflabel.com/ingredients/tris-biphenyl-triazine/

Chemical (organic) UV filter · Reef research: Limited data

# Tris-Biphenyl Triazine (Tinosorb A2B)

A newer particulate filter approved in the EU.

Banned in

-   Palau

Also excluded where only mineral sunscreen is allowed

-   Maui County
-   Hawaiʻi County

Not approved in the US, so US sunscreens do not contain it.

## Where it’s restricted

Named in the law or guidance

| Location | Status | Since |
| --- | --- | --- |
| [Palau](https://reeflabel.com/locations/palau/) [law text ↗](https://www.palaugov.pw/wp-content/uploads/2018/10/RPPL-No.-10-30-re.-The-Responsible-Tourism-Education-Act-of-2018.pdf) | In force | January 1, 2020 |

### Also not allowed under mineral-only rules

Tris-Biphenyl Triazine (Tinosorb A2B) isn’t named in these laws, but they allow only mineral (zinc oxide or titanium dioxide) sunscreens, so a product containing it is excluded anyway.

-   [Maui County (Maui, Molokaʻi, Lānaʻi)](https://reeflabel.com/locations/maui-county/) (in force since October 1, 2022)
-   [Hawaiʻi County (Big Island)](https://reeflabel.com/locations/hawaii-county/) (in force since December 1, 2022)

## What the reef research says

A 2026 screening study of nine cosmetic UV filters included tris-biphenyl triazine (TBT). Under a conservative exposure scenario, the predicted water and sediment concentration ratios were acceptable for TBT. A separate 2026 acute test on algae and water fleas covered three other triazine filters (BEMT, DBT and EHT), and this filter was not among them. No measured coral or reef-species toxicity study for this filter appeared in the searches run.

-   [Integr Environ Assess Manag 2026: New Approach Methodologies in aquatic hazard and risk assessment of cosmetic UV filters (doi:10.1093/inteam/vjag121)](https://pubmed.ncbi.nlm.nih.gov/42503170/)
-   [Ecotoxicol Environ Saf 2026: Acute toxicity of novel triazine-based UV filters towards Chlorella vulgaris and Daphnia magna (doi:10.1016/j.ecoenv.2025.119584)](https://pubmed.ncbi.nlm.nih.gov/41411795/)

**Related ingredients:** [Bemotrizinol (Tinosorb S)](https://reeflabel.com/ingredients/bemotrizinol/), [DHHB (Uvinul A Plus)](https://reeflabel.com/ingredients/diethylamino-hydroxybenzoyl-hexyl-benzoate/), [Ethylhexyl Triazone (Uvinul T 150)](https://reeflabel.com/ingredients/ethylhexyl-triazone/)

Last reviewed October 14, 2026.

### Label names we match

-   tris-biphenyl triazine
-   tris biphenyl triazine
-   tinosorb a2b

### Regulatory status

**Wikidata:** [Q15731461](https://www.wikidata.org/wiki/Q15731461)

**US FDA:** Not approved in the US.

**EU:** Approved (nano), max 10%.

**Protects against:** UVB + UVA-II.