Grandfathered Sunscreen Chemicals

Why legacy approvals can become harmful in a modern sunscreen market

Grandfathering is a regulatory mechanism where ingredients already in use before modern rules were introduced are allowed to remain on the market without being re-approved under today’s evidence standards. In Australia, the TGA notes that a number of sunscreen ingredients were already supplied before the Therapeutic Goods Act 1989 commenced, and these ingredients sit on the TGA’s pre-approved permissible list used for therapeutic sunscreens. (Therapeutic Goods Administration (TGA))

What changed since these ingredients were first allowed

Many legacy UV filters were accepted when regulators mainly evaluated short-term toxicity, basic irritation, and whether the ingredient blocked UV. Modern sunscreen science now expects far more, including human pharmacokinetics under maximal use, better endocrine screening, updated genotoxicity approaches, modern impurity control, and exposure modelling that matches real-world behavior. The TGA’s own sunscreen ingredient framework is built around the Permissible Ingredients Determination and evolving data expectations. (Therapeutic Goods Administration (TGA))

Why grandfathering can be harmful

Grandfathering is not “nothing was checked.” The problem is that the original check often used old assumptions that no longer hold. Harm arises when the market keeps changing but the evidence base does not, especially in a high-use country like Australia.

Problem 1: Systemic absorption was not a core requirement back then

A key modern shift is that many UV filters are now known to be systemically absorbed under real-world sunscreen use. Once systemic exposure exists, safety can no longer rely on the old idea that the ingredient stays on the surface. This is why regulators in multiple jurisdictions treat systemic absorption as a trigger for more data, not as proof of harm, but as proof that older assumptions are incomplete. (FDA Access Data)

Problem 2: Endocrine activity creates a different evidence burden

Legacy frameworks were not designed for endocrine-active signals. Endocrine risk assessment often requires more data and different logic than classical “high-dose toxicity” models, particularly for chronic exposure and sensitive windows such as pregnancy or early development. This is one reason regulators increasingly revisit older filters even when acute toxicity looks low.

Problem 3: Modern exposure patterns are higher than older safety assumptions

Australia’s sunscreen context is extreme: high UV index, frequent reapplication, and large-area application. When modern Australian exposure modelling is applied, margins of safety can tighten for some ingredients compared with older assessments. This is not theoretical. In its 2025 review, the TGA highlighted that Australian conditions and available data were part of why certain actives were prioritized, and it recommended stronger controls for some commonly used filters. (Therapeutic Goods Administration (TGA))

Problem 4: Impurities and degradation products were not managed to modern standards

Grandfathered approvals often focus on the parent ingredient, but modern product risk is also about what the ingredient turns into during storage and use, and what impurities are present from synthesis. The TGA’s recent work on sunscreen ingredients includes attention to these modern considerations, including constraints proposed for specific impurities in the sunscreen context. (Therapeutic Goods Administration (TGA))

Problem 5: “Active vs excipient” ambiguity can hide SPF-relevant chemicals

A growing blind spot is that some chemicals can absorb UV and boost SPF performance without being listed as actives in the way consumers expect. If a substance meaningfully contributes to UV attenuation, it functions like an active ingredient in practice, even if it is not labeled or regulated that way in some product categories. This has become a real-world issue in Australia, including reporting that some products marketed as “mineral” contained additional UV absorbers not clearly disclosed as such. (The Guardian)

Problem 6: Regulatory divergence becomes confusing and trust-eroding

When a legacy ingredient is restricted or removed in one jurisdiction but remains permitted elsewhere, consumers receive mixed signals. Some jurisdictions restrict primarily due to environmental concerns, others focus on human systemic exposure, and others prioritize data sufficiency. The EU’s allowed UV filter list and restrictions evolve via Annex VI updates, illustrating how quickly the international baseline can move compared with legacy settings. (European Chemicals Agency)

A practical example of how grandfathering plays out in Australia

Australia recently conducted a focused safety review on seven sunscreen actives, using national and international assessments and available toxicokinetics, and identified where controls should be strengthened under Australian use conditions. (Therapeutic Goods Administration (TGA)) This type of targeted review highlights the core grandfathering problem: if only a subset is reviewed, many other legacy ingredients can remain in regulatory limbo for long periods without a transparent, modern reassessment.

The core issue in one sentence

Grandfathering can be harmful because it preserves market access based on historical assumptions, while modern sunscreen use, modern toxicology, and modern formulation chemistry can all change the real risk profile.

What a safer path looks like

A modern approach does not require panic or anti-sunscreen messaging. It means regularly re-testing legacy UV filters against current expectations, especially for systemic absorption, endocrine signals, impurities and degradation products, and real-world exposure modelling in high-use settings like Australia. It also means closing the “SPF booster excipient” loophole by ensuring any ingredient that materially contributes to UV protection is assessed with the same rigor and transparency expected of actives. (Therapeutic Goods Administration (TGA))

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About the Australian Sunscreen Council

The Australian Sunscreen Council (ASC) is dedicated to protecting public health by championing the highest standards in sunscreen safety, testing, use and transparency.

Our mission is to ensure that all sunscreen and related products available to Australians meet or exceed the latest scientific evidence on ultraviolet (UV) protection and human health.

We promote balanced, evidence-based sun safety guidance, recognising that sunscreen is only a small part of the overall picture when it comes to sun safety and health. Our approach is holistic: effective UV protection includes shade, clothing, behaviour, and thoughtful timing of exposure—not sunscreen alone.

The ASC also supports greater public awareness of the documented benefits of moderate sun exposure, including vitamin D synthesis, improved mental wellbeing, and nitric oxide release—a process linked to healthier cardiovascular function and improved blood pressure regulation. We believe Australians deserve clear, science-backed advice that helps them understand how to obtain these benefits safely.

The ASC works collaboratively with government agencies, dermatologists, and public health experts to improve sunscreen standards and to support balanced, science-driven sun safety advice for all Australians.

Learn more at www.australiansunscreencouncil.org