Your sunscreen is a pollutant.
It gets into our waters indirectly (sewage, fresh, sea) via wastewater (bath, laundry, and pool water) or directly from our skin and clothes when we’re swimming. Sunscreen’s pretty much in majority of our personal care products even if it’s not stated on the label.
Organic sunscreens biodegrade, but build up in sediment and some marine life. They possibly cause coral bleaching by promoting viral infections.
Inorganic sunscreens do not biodegrade and potentially becomes sediment which causes coral bleaching by blocking sunlight.
There’s no such thing. You’ve probably heard of them. They’ve been making headlines on and off in recent years, with oxybenzone being the most well-known culprit. Right now we’re working on a “lesser evil” type of scenario. While some organic sunscreens are proven to be harmful, inorganic sunscreens aren’t harmless. But they are the lesser evil with the current body of knowledge we have right now.
If you want to learn more about the reef-friendly label, I wrote a post HERE. It’s quite long, but a lot more in-depth.
So why do all these brands market reef-friendly sunscreens?
Sometimes it’s a marketing tactic, other times it’s just misinformed. Current consensus is zinc oxide is better. Not necessarily good, but better. Headlines just shout “chemical sunscreens cause coral bleaching” for clickbait. So as of now, they are reef-friendlier sunscreens, but they’re not harmless.
You should definitely still use sun protection.
But consider the alternatives.
If you’re not a hardcore environmentalist, I’ve included a list below of brands you can choose from that are reef-friendlier for when you go to the beach. If you are willing to take the extra step, consider alternative forms of protection like UV-blocking umbrellas and clothing/swimwear.
EDIT 07/12/17: I will be confirming with these brands how they created and tested the SPF of their sunscreens before recommending them. I’ll be removing the list in the meantime and updating them as I go along.
Climate change is still the biggest cause of coral bleaching.
But changing your skincare products helps tons. Choosing reef-friendlier sunscreens minimizes direct pollution, choosing reef-friendlier products for your whole routine minimizes indirect pollution. Some suggestions:
- Make your face mask wrappers, samples, and plastics into ecobricks
- Minimize the use of occlusives or use completely biodegradable ones like facial oils because occlusives don’t fully absorb into your skin.
- Do not use other skincare products before entering the ocean. Wash off any residue from existing products before entering the ocean and use the minimum amount of sunscreen needed.
- Do not touch or step on corals.
- Switch to reef-friendlier products in your whole skincare routine as washing them off appears to bring the most skincare pollutants into the ocean.
If you’d like to go the extra mile, the following would also be great:
- Sign the petition against Nickelodeon in Coron.
- Call out brands and bloggers that market their sunscreens for beach use without a clear warning.
- Ask brands to consciously create reef-friendly sunscreens.
- Demand brands to clearly state on their label how reef-safe their sunscreens are.
And if you’re interested in learning more about marine conservation as a whole, Save Philippine Seas is a great resource.
If you’re interested in further reading, check out these sources! These were my faves as they’re easier to understand and gives a great overview of the issue.
Sunscreens Cause Coral Bleaching by Promoting Viral Infections
A few excerpts:
“Results: Sunscreens cause the rapid and complete bleaching of hard corals, even at extremely low concentrations. The effect of sunscreens is due to organic ultraviolet filters, which are able to induce the lytic viral cycle in symbiotic zooxanthellae with latent infections.Conclusion: We conclude that sunscreens, by promoting viral infection, potentially play an important role in coral bleaching in areas prone to high levels of recreational use by humans.”
“Our results indicate that sunscreens promoting lytic cycle in viruses can cause coral bleaching. Because human use of tropical ecosystems and coral reef areas is progressively increasing, we predict that the impact of sun-screens on coral bleaching will grow considerably in the future on a global scale. Actions are therefore needed to stimulate the research and utilization of UV filters that do not threaten the survival of these endangered tropical ecosystems.”
Cosmetic Ingredients as Emerging Pollutants of Environmental and Health Concern. A Mini-Review
The toxicity of organic UV filters was evaluated in several aquatic organisms; some frequently used UV filters have proven to be toxic for phytoplankton species, microalgae, protozoa, and crustaceans ( and the literature therein). Danovaro et al.  demonstrated that some UV filters (EHMC, BP-3, and 4-MBC) can cause coral bleaching at very low concentrations; the results of their experiments, jointly with the estimated release of sunscreens in reef areas, strongly suggest that at least 10% of the reefs are likely to meet coral bleaching due to UV filters pollution.
Are sunscreens a new environmental risk associated with coastal tourism?
Sorry, guys. This one isn’t open source so here’s an excerpt explaining the possible effect of inorganic sunscreens since organic sunscreens are usually the ones being studied in this topic:
Once in the seawater they [zinc oxide and titanium dioxide] can interact with aquatic organisms in different ways: adsorption to the surface of microorganisms, cellular internalization, trapping by filter feeder organisms (e.g. bivalves), ingest by benthic fauna from the sediments or uptake by fish (Baker et al., 2014). Sánchez-Quiles and Tovar-Sánchez (2014) estimated that in a touristic beach during a summer day about 4 kg of TiO2 nanoparticles could be released from sunscreens into seawater.
Just a quick note: don’t listen to internet articles and websites. Their agendas are clear and the reason the topic seems so conflicted is because of these articles. There’s no conflict within the marine science community because there’s just not enough research yet, so we work with the ones we do have. None have definitively taken a one-sided stance but many internet articles have, which is why I urge you to search journals instead of Google.
If you’re interested in learning more or want more information on a specific sunscreen, feel free to contact me! I try to be as responsive as possible, but I’m not an expert on the topic so if your question is difficult to answer, just give me some time to look up some resources!