Best Non-Toxic Sunscreens: Safe for You and the Ocean
- Jana Davis
- Apr 29
- 4 min read
Updated: Apr 30
Sun protection starts from the inside out. While sunscreen is essential, one of the most overlooked ways to defend your skin is through your diet. A diet rich in colorful fruits and vegetables supplies your body with antioxidants like vitamin C, vitamin E, beta-carotene, and polyphenols—compounds that help neutralize free radicals generated by sun exposure. These antioxidants work at the cellular level to protect your skin from oxidative stress, which is the main cause of UV-induced skin damage.

Understanding Sun Damage
When ultraviolet (UV) rays from the sun penetrate your skin, they generate free radicals—unstable molecules that can damage DNA, break down collagen, and accelerate skin aging. Over time, this oxidative stress can lead to visible signs of aging (like wrinkles and dark spots) and increase the risk of skin cancer.
That’s why a two-pronged approach—internal protection through nutrition and external protection through sun-safe products—is the most effective strategy.
Sunscreen is essential for protecting our skin from the sun’s harmful UV rays, but the type of sunscreen you use can also have a major impact on the environment—especially our oceans. Fortunately, non-toxic, mineral-based sunscreens offer a safer alternative for both people and marine ecosystems. We will also review what ingredients to avoid. I have spent years educating clients on how to protect their health from chemicals as well as working to protect our oceans. We can do both by making better sunscreen choices.

How Sunscreen Enters the Environment
Many people don’t realize that the sunscreen they apply may not stay on their skin. When we swim, shower, or even sweat, chemicals from sunscreen can wash off and enter rivers, lakes, and oceans. These chemicals can linger in the water and accumulate in marine organisms, disrupting ecosystems and harming aquatic life.
The Impact on Marine Life
Scientific studies have shown that certain sunscreen chemicals can negatively affect a wide variety of marine species:
Green Algae: Impaired growth and photosynthesis
Coral: Tissue accumulation, bleaching, DNA damage, developmental deformities, and even death
Mussels & Sea Urchins: Reproductive defects and deformities in young
Fish: Lower fertility, impaired reproduction, and feminization of male fish
Dolphins: Chemical accumulation in tissue, which can be passed to offspring

Harmful Chemicals to Avoid
Common chemical UV filters in conventional sunscreens that have been linked to environmental harm include:
Oxybenzone
Octinoxate
Octocrylene
Benzophenone-1 & -8
OD-PABA
4-Methylbenzylidene camphor
3-Benzylidene camphor
Nano-sized titanium dioxide and zinc oxide
In fact, due to these environmental concerns, places like Hawaii, Palau, Bonaire, and Aruba have enacted bans on sunscreens containing oxybenzone and octinoxate.
What Makes a Sunscreen “Non-Toxic”?
Mineral sunscreens—also known as physical sunscreens—use zinc oxide or titanium dioxide to reflect UV rays rather than absorb them. However, not all mineral sunscreens are created equal. The particle size matters greatly:
Non-nano zinc oxide is considered one of the safest options for both humans and marine life. I recommend using a product that is just zinc oxide and does not contain titanium dioxide for the lowest level of chemical exposure.
Nano zinc oxide and nano titanium dioxide carry important concerns.
Environmental and Health Risks of Nano Zinc Oxide
Nano zinc oxide (ZnO nanoparticles) may offer clear application and strong UV protection, but emerging research suggests possible downsides:
Environmental Risks:
Marine Toxicity: Nano zinc oxide can be toxic to marine organisms, including crustaceans, fish, and algae. Like nano titanium dioxide, it may generate reactive oxygen species (ROS) under UV light, leading to oxidative stress and damage to aquatic life.
Bioaccumulation: These particles can accumulate in marine animals and sediments, potentially entering the food web.
Ecosystem Disruption: Disruptions to reproductive health (endocrine disruptors) and developmental processes in aquatic organisms have been observed.
Human Health Risks:
Inhalation: Similar to nano titanium dioxide, inhaling nano zinc particles—especially from sprays or powders—can pose respiratory risks and trigger oxidative stress in the lungs.
Dermal Penetration: On intact skin, absorption is minimal, but in damaged or compromised skin, nanoparticles may penetrate deeper layers, raising safety questions.
Long-Term Safety: There is still limited data on long-term exposure to nano zinc oxide in humans, prompting caution in its widespread use.
A 2020 study in Frontiers in Public Health highlighted the toxic effects of zinc nanoparticles on marine crustaceans and raised concerns about human health impacts withchronic exposure.
Safer Alternatives
To protect both your health and the environment, consider these tips:
Choose mineral sunscreens with non-nano zinc oxide as the active ingredient. These are now available in clear formulations—no more chalky white noses!
Avoid aerosol sprays and powders that may contain inhalable nanoparticles.
Wear UV protective clothing like sun shirts and wide-brimmed hats.
Seek shade between 10 a.m. and 2 p.m. when the sun is strongest.
Use products labeled “reef-safe”, but still check the ingredients—there’s no regulatory standard for this term.
Here are the links to a few of my top pick for sunscreen brands: :
Fullscript also carries several brands of pure zinc oxide sunscreen including Badger if you would like to purchase at 20 percent off, please just email me at jana@carolinagreenliving.com and I will provide a discounted link.
Final Thoughts:
Protecting your skin shouldn’t come at the cost of harming marine life or putting your health at risk. By switching to non-toxic sunscreens and sun-smart habits, we can enjoy the outdoors responsibly—preserving our oceans while keeping ourselves safe.
References:
Vimercati L, Cavone D, Caputi A, De Maria L, Tria M, Prato E, Ferri GM. Nanoparticles: An Experimental Study of Zinc Nanoparticles Toxicity on Marine Crustaceans. General Overview on the Health Implications in Humans. Front Public Health. 2020 May 21;8:192. doi: 10.3389/fpubh.2020.00192. PMID: 32509719; PMCID: PMC7253631.
Rashid MM, Forte Tavčer P, Tomšič B. Influence of Titanium Dioxide Nanoparticles on Human Health and the Environment. Nanomaterials (Basel). 2021 Sep 10;11(9):2354. doi: 10.3390/nano11092354. PMID: 34578667; PMCID: PMC8465434
Jana Davis MS,RDN
Functional Registered Dietitian Nutritionist and Environmentalist
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