With sunblock it's relatively easy to know what to look for in terms of SPF, UV types etc, however with eco-friendly ones that aim to not put chemicals back in the ocean (used by surfers, swimmers, divers etc) it seems a bit less clear.

What should you look for when purchasing an eco-friendly sunblock, are there ingredients to aim for or avoid?

  • 2
    Oh nice, I just recently had a discussion about that. Probably came up because of the Hawaii ban recently. And I always thought that doesn't apply to me while mountaineering, but given that many of these chemicals can't be removed in sewage treatment plants it does eventually get into the ocean too when I shower it off. So I am really curious about answers to this!
    – imsodin
    Commented Jun 28, 2019 at 11:20
  • @imsodin yes, thinking about how easily you can impact the ocean without going near it is quite a big thing in the news etc atm as well!
    – Aravona
    Commented Jun 28, 2019 at 11:24

2 Answers 2


This article has a list of what chemicals to avoid, why, and some good sunscreen choices. The three main points are below. Note that titanium dioxide falls under physical sunscreen but is still harmful! So saying physical is okay but chemical ones are not is FALSE.

I personally have used Raw Elements and Stream2Sea before and been pretty happy with them.

Avoid sunscreens containing petrolatum, commonly known as mineral oil, which takes years to biodegrade, and are known to be harmful or fatal to aquatic life and waterfowl.

Avoid sunscreens with high content of Titanium Dioxide. This mineral does not biodegrade and is found to react in warm seawater to form hydrogen peroxide which is harmful to all sea life.

Oxybenzone and octinoxate, the two chemicals recently banned in Hawaii and are believed to cause coral bleaching.


Sunblock comes in two variants- physical and chemical. Physical ones work just by being present on your skin, and and usually contain a mineral like zinc or titanium. Chemical ones are the ones to definitely avoid, as they use oxybenzone, etc.

That being said, the best sun protection is to use long sleeves (à la rashguards or wetsuits) in the water, to reduce the overall amount of sunblock being washed into the ocean. Even with naturally-occurring minerals in physical sunblock, there can be other trace ingredients that aren't as eco-friendly.

  • I think you need some references to support the argument cloths are better then lotions. clothes pollute the oceans Commented Jun 28, 2019 at 14:51
  • 1
    The statement about physical being always better is false
    – noah
    Commented Jun 28, 2019 at 16:39
  • 1
    @JamesJenkins good point. From an ecological perspective, perhaps the solution is to just stay out of the water entirely.
    – Quinto
    Commented Jun 28, 2019 at 16:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.