The Watch List™
What we watch:
UV filters • persistence chemicals • reef-risk claims • endocrine activity signals • formulation opaqueness
The Watch List™ explores ingredients, claims and formulation topics commonly discussed in sunscreen conversations. Inclusion does not automatically indicate risk, and context, concentration, formulation and regulation all matter.
The ingredients you do want in your sunscreen > The Sunscreen List™
Chemical Filters
Organic / chemical UV filters currently included within The Watch List™
Octisalate
PBSA (Phenylbenzimidazole Sulfonic Acid / Ensulizole)
4-MBC (4-Methylbenzylidene Camphor / Enzacamene)
Padimate O
Hybrid UV Filter Systems
Category:
Active filters, often Chemical, sometimes with Zinc Oxide
Combination of mineral + organic UV filters in one formula.
What it is
Common in beauty and family brands, not always transparent in labeling - 'reef safe' claims are not proven or regulated.
Why it’s on The Watch List™
- Multiple UV filters used together can appear in “mineral” or “reef-safe” products
- Increases formulation complexity and exposure pathways
- Includes filters under global review (e.g. oxybenzone, homosalate)
Watch for these ingredients: - oxybenzone • homosalate • octocrylene • avobenzone • octisalate
1. Oxybenzone
What it is
A chemical UV filter used to absorb UV rays.
Why it’s on The Watch List
Linked to coral bleaching and endocrine disruption concerns. Widely restricted in reef-sensitive regions.
SunSafe® Tags
Reef, Endocrine, UV Filter
2. Octinoxate
What it is
A chemical UV filter that protects against UVB rays.
Why it’s on The Watch List
Associated with coral reef damage and potential hormone disruption.
SunSafe® Tags
Reef, Endocrine, UV Filter
3. Octocrylene
What it is
A UV filter used to stabilise other sunscreen ingredients.
Why it’s on The Watch List
Can degrade into benzophenone, a compound of concern for human and environmental health.
SunSafe® Tags
Persistence, Endocrine, UV Filter
4. Homosalate
What it is
A chemical UV filter used in many SPF formulations.
Why it’s on The Watch List
- Detected as a systemic UV filter (absorbed into the body in studies)
- Shows endocrine activity signals in laboratory research, prompting ongoing scientific review
- Often used at higher concentrations to achieve SPF targets, increasing total exposure potential
- Included in current regulatory reassessment discussions in multiple regions
- Frequently appears in daily-use sunscreen products, increasing repeated exposure relevance
SunSafe® Tags
Endocrine, UV Filter, endocrine disrupter, chemical sunscreen, hybrid sunscreen, homoslate
5. Avobenzone
What it is
A UVA-filtering chemical sunscreen ingredient.
Why it’s on The Watch List
Photo-unstable on its own and often requires stabilisers, increasing formulation complexity and environmental load.
SunSafe® Tags
UVFilter, Persistence
6. Octisalate
What it is
A UVB-absorbing chemical sunscreen filter often used to boost SPF performance and improve water resistance.
Why it’s on The Watch List
Frequently used alongside multiple UV filters in hybrid and chemical systems. Included due to cumulative formulation load, repeated exposure considerations and broader transparency discussions around multi-filter sunscreen systems.
SunSafe® Tags
UV Filter, Hybrid Sunscreen, Formulation Complexity
7. PBSA (Phenylbenzimidazole Sulfonic Acid / Ensulizole)
What it is
A water-soluble UVB filter commonly used in lighter daily SPF formulations.
Why it’s on The Watch List
Included for ongoing review around environmental persistence, aquatic exposure pathways and evolving global ingredient discussions.
SunSafe® Tags
UV Filter, Water Soluble, Environmental Review
8. 4-MBC (4-Methylbenzylidene Camphor / Enzacamene)
What it is
A UVB sunscreen filter historically used in some international formulations.
Why it’s on The Watch List
Included due to international regulatory discussions and endocrine activity research signals.
SunSafe® Tags
Endocrine, Regulatory Review, UV Filter
9. Padimate O
What it is
A UVB chemical sunscreen ingredient related to PABA-derived chemistry.
Why it’s on The Watch List
Included due to historical safety discussions and reduced modern use compared with newer filters.
SunSafe® Tags
UV Filter, Legacy Filter, Ingredient Watch
10. Benzophenone-1 (and related compounds)
What it is
A UV stabiliser and degradation byproduct of some sunscreen filters.
Why it’s on The Watch List
Linked to endocrine disruption and environmental persistence.
SunSafe® Tags
#Endocrine, #Persistence
11. VP/Eicosene Copolymer
What it is
A synthetic film-forming agent that improves water resistance.
Why it’s on The Watch List
Does not readily biodegrade and may contribute to microplastic-type pollution.
SunSafe® Tags
Persistence chemical, PFAs
12. Acrylates Copolymer
What it is
A group of synthetic polymers used for film-forming and texture.
Why it’s on The Watch List
Associated with microplastic pollution due to environmental persistence.
SunSafe® Tags
Persistence chemical, PFAs
13. Silica Dimethyl Silylate
What it is
A modified mineral used to improve texture and create a matte finish.
Why it’s on The Watch List
Not biodegradable and contributes to environmental particulate load.
SunSafe® Tags
#Persistence
14. PFAS (Per- and Polyfluoroalkyl Substances)
What it is
A group of human-made chemicals used for water resistance, durability and long wear.
Why it’s on The Watch List
PFAS have been found in human blood worldwide — including children, babies and even umbilical cord blood. They’re nicknamed “forever chemicals” because some can stay in the body and environment for years.
The concern?
- increased cholesterol
- liver changes
- hormone disruption
- lower birth weights
- higher risk of kidney and testicular cancer in heavily exposed populations
For oceans, the list of issues keeps going — PFAS persist in waterways and wildlife long after use.
SunSafe® Says
Not a sunscreen active. More of a “why is this here?” ingredient.
Retinyl Palmitate
What is it?
A vitamin A derivative added to some sunscreens for skin-conditioning and anti-ageing benefits.
Retinyl Palmitate is not a sunscreen active and does not contribute to SPF protection.
Why it’s on The Watch List™
Concerns around Retinyl Palmitate come from FDA / NTP-linked mouse studies investigating vitamin A compounds under UV exposure.
The concern relates specifically to sunlight exposure!
In the studies:
- creams containing Retinyl Palmitate were applied to mice
- mice were then exposed to simulated sunlight / UV radiation
- mice exposed to sunlight and Retinyl Palmitate developed skin damage and tumours earlier than the comparison group
- some summaries reported this happened up to ~21% faster
The ingredient raises a simple question:
Why add an anti-ageing ingredient with UV-reactivity concerns to a product designed for sun exposure?
SunSafe® Says:
Don't risk it. Proof of risk lies herein use with prolonged UV exposure, frequent reapplication, children, sensitive skin and marine environments.
Read More:
The Ingredient List™ | Case Studies
References:
Environmental presence + persistence
https://pmc.ncbi.nlm.nih.gov/articles/PMC9652235/
Toxicological + formulation effects (marine systems)
https://www.sciencedirect.com/science/article/pii/S0269749122014269
Human exposure + biological interaction
https://www.mdpi.com/2305-6304/13/2/110
Regulatory + absorption studies context
https://www.tga.gov.au/news/media-releases
PFAs
- World Health Organization
- Centers for Disease Control and Prevention
- U.S. EPA — PFAS Health Effects
- National Library of Medicine & National Center for Biotechnology Information
Retinyl Palmitate
• National Toxicology Program — Photocarcinogenesis Study of Retinyl Palmitate
