Chemical v Mineral Sunscreen

Chemical vs Mineral Sunscreens: What We Put on Our Skin Matters for Our Oceans Too

Living by the coast in Cornwall, the sea is part of everyday life for me. It is where I walk, reset, and feel most connected to nature. It is also a constant reminder that the choices we make in our daily routines ripple far beyond ourselves and sunscreen is one of those choices.

Protecting our skin from sun damage is essential. I would never suggest otherwise. But over recent years, I have become increasingly interested in the environmental impact of sunscreen ingredients, especially the difference between chemical and mineral formulations and what they mean for marine life.

At Scence, we spend a lot of time thinking about ingredients, not just how they perform, but where they end up once they wash down the drain or into the sea. June 1 was Reef Awareness Day and I spoke earlier this month about how sunscreens affect coral reefs but meanwhile here is a quick guide to chemical v mineral sunscreen.

What Is the Difference Between Chemical and Mineral Sunscreens?

Chemical sunscreens use synthetic UV filters such as oxybenzone, octinoxate, avobenzone, and octocrylene. These ingredients absorb UV rays and convert them into heat.

Mineral sunscreens work differently. They use natural mineral filters, usually zinc oxide or titanium dioxide, which sit on the skin and reflect UV radiation away from the body.

From a skincare perspective, chemical sunscreens are often favoured for their lightweight texture and invisible finish. Mineral sunscreens can feel richer or leave a slight white cast, although formulations have improved enormously in recent years.

But the biggest difference may not be how they feel on our skin. It is how they behave once they enter the environment.

The Problem with Chemical Sunscreens

Every time we swim wearing sunscreen, small amounts wash directly into the ocean. Sunscreen also enters waterways through showers, laundry, and wastewater systems. Research has shown that certain chemical UV filters can harm marine ecosystems, particularly coral reefs.

Oxybenzone, one of the most commonly discussed ingredients, has been linked to coral bleaching, DNA damage, and disrupted coral development. Even very low concentrations appear capable of affecting fragile reef systems.

Octinoxate has also been associated with coral toxicity and impaired marine growth processes.

What concerns me personally is that these ingredients do not simply disappear. They persist in the environment and can accumulate in marine organisms over time. Studies have also found chemical UV filters in fish, algae, and seawater, with evidence suggesting they may interfere with hormone systems in aquatic species.

For me, this is where the conversation shifts from beauty to responsibility.

Are Mineral Sunscreens Better?

Mineral sunscreens are generally considered the more ocean-friendly option, particularly non-nano zinc oxide formulations. Because mineral filters are more stable and less biologically active in marine environments, they appear to pose fewer risks to coral reefs and aquatic life compared with certain chemical UV filters.

That does not mean they are entirely impact-free. Any ingredient produced at scale has an environmental footprint. But current evidence suggests mineral sunscreens are the gentler choice for marine ecosystems.

At Scence, we believe sustainability is often about choosing the least harmful option while continuing to improve formulations over time.

Why This Conversation Matters

I think many consumers genuinely want to make better choices, but the beauty industry can be overwhelming. Terms like “reef-safe” are not always regulated, and marketing claims can create confusion.

For me, transparency matters. Understanding ingredients should not feel intimidating. The good news is that consumers are becoming far more ingredient-aware and environmentally conscious. More people are asking:

• What happens after I use this product?
• Where do these ingredients go?
• What effect do they have on the environment?

Those are exactly the kinds of questions that drive positive change.

Finding a Balanced Approach

I do not believe in fear-based skincare. Sun protection is vital for preventing premature ageing and reducing skin cancer risk. The goal is not to avoid sunscreen, but to choose formulations more thoughtfully.

A balanced approach might include:

• Choosing mineral-based sunscreens where possible
• Avoiding ingredients such as oxybenzone and octinoxate
• Wearing hats and UV-protective clothing
• Reapplying sunscreen responsibly rather than excessively

Small changes really do add up.

A More Conscious Future

One of the things I love most about building Scence is seeing how consumer expectations are changing. People no longer want products that simply work. They want products that align with their values. That includes protecting oceans, reducing pollution, and making more mindful ingredient choices. Sustainability is not about perfection. None of us gets everything right all the time. It is about awareness, progress, and doing better where we can. And perhaps that starts with something as simple as the sunscreen we choose before stepping into the sea.

Thanks for reading!

Krista

PS… Did you know that 5 June is World Environment Day?