Toxic Sunscreen: A Sailboat Captain’s Experience

By: Partners, Product Review, Safety

By Kim Walther, ASA Instructor

Working as a boat captain, I see a huge variety of sunscreen brands. It’s always interesting to check out what my sailing school students or charterers bring with them. I like to read what’s on the front, and then look at the back.  It’s absolutely incredible that some brands that we perceive as being very good for us and the environment actually include those poisonous chemicals. I found that out the hard way, when I used a sunscreen that I thought was wonderful and I ended up being poisoned by the ingredients! You can read more about that at The Summer I Got Poisoned by Chemical Sunscreen. That experience led me to conduct a lot of research and choose Stream2Sea since their founder, chemist Autumn Blum, creates totally, truly reef-friendly products. She’s also a scuba diver like me, and I trust her and her natural ingredients and extensive testing and research.

While I have never heard of anyone getting poison from their shampoo, conditioner, body lotion or body wash, since all of those products are washed down the drain; we need to be aware of the chemicals there as well. What goes in your drain flows to the ocean, even when you are not on a sailboat. Yes, those pollutants are more diluted, but “forever” chemicals and plastics will last forever.

It’s so important for boaters to be aware of toxic chemicals in every product you use onboard daily since a lot of those ingredients end up back in the water under the hull through gray water emissions. More and more, boaters are becoming aware that it’s not only the chemicals in sunscreen but also the products that they put on their body that can harm the environment. Shampoo, conditioner, body wash, hand sanitizer, lotion – all can contain harmful ingredients. Other products we boaters use as well can harbor unwanted chemicals. Some cleaners such as laundry detergents and dishwashing soap have harmful ingredients that contribute to bleaching our coral reefs and killing the fish. While people on land may believe that the water from their shower or dishes never reaches the ocean – it does. We boaters know exactly where our shower water and dishwashing water ends up, right under the boat and into the water.

How Sunscreen Can Be Bad for Boaters and Fish

Sunscreen is a big concern on boats for boaters. Not only do we apply this chemical to our bodies daily if not nearly hourly; it also ends up in the water. When we touch or sit on the boat; the chemicals are transferred to the boat. Then when we wash the boat, the chemicals end up in the water. Also, spray sunscreens create a lot of overspray which not only finds its way into the water but also makes the boat slick and dangerous. Most boat rental companies prohibit the use of spray sunscreen for that reason.

As consumers become more eco-conscious, we learn there are a lot of differences between types of sunscreen. One confusing distinction is between “physical” and “chemical” sunscreens. Sometimes you hear of “chemical-free sunscreens.” All sunscreens have chemicals. However, many chemicals are organic. No wonder it’s all confusing!

Banned Toxic Ingredients

The active ingredients in chemical sunscreens might be ones you have heard of that are banned in Bonaire, Palau, Hawaii, and Key West. They are oxybenzone, octinoxate, octisalate, and avobenzone. 

One of those poisons, oxybenzone, has enough toxicity that a single drop of sunscreen in the equivalent of six and a half Olympic-size swimming pools can be enough to cause serious damage to coral according to That’s why we’re hearing more and more about popular vacation destinations banning toxic sunscreens. Toxins in sunscreen kill reefs and fish, which is what tourists come to see. No wildlife means no tourism income, so it’s very important to local incomes to protect their natural attractions.  The products that we use while boating to moisturize our skin, shampoo and conditioner our hair, and even body wash also end up directly overboard. That’s why it’s so important that we monitor the ingredients in the products that we use because plenty of labels are misleading.

Ingredients to Avoid

  • Oxybenzone
  • avobenzone 
  • avobenzine 
  • ethylhexl 
  • methoxycinnamate 
  • octinoxate 
  • benzophenone
  • retinyl palmitate
  • homosalate
  • octisalate 
  • octocrylene
  • nanoparticles and more are related to health concerns. You can read more about how bad those ingredients are here.  

These effects range from cancer to allergies, organ system toxicity, and endocrine disruption. A quick scan of ingredients can help you decide if this is something that you want touching your body or entering the ocean.


One company has made it so easy to know if the products you are using are truly reef-friendly and biodegradable – Stream2Sea.

Stream2Sea’s creator, Autumn Blum, decided to produce natural products safe for fish and humans. On a dive trip to Palau, she noticed that tell-tale sheen on the water  from sunscreen and wondered about the effect on marine life. Blum decided to do something about it, and used her chemist background to formulate sunscreen. Then she saw a need for shampoo and conditioner, then mask defog – and the list continues.  Her latest natural and safe products are hand sanitizer and stick sunscreens. 

Now you can do something to help the environment, too – use products you have thoroughly researched, or, leave it up to Stream2Sea to supply you with products you have total confidence will not harm the waterways.

ASA Members receive a 20% off coupon on Stream2Sea products with a special promo code available in the Members Portal.

Misleading Marketing

It’s concerning that sunscreens routinely feature words on the front of the bottle that can be misleading and downright untruthful. Words like “natural, reefs safe, environmentally friendly actually don’t have a lot to do with the list of ingredients on the back of the bottle. Turn it over, and check for yourself. Even when products call themselves “reef safe “or “waterway friendly,“ the astute boater needs to read a bit further and recognize some of the main undesirable ingredients listed on the back.

ASA Members receive a 20% off coupon with a special promo code available in the Members Portal.

Kim Walther is a sailing instructor at St. Augustine Sailing in Northeast Florida. Her passion for the ocean and sailing comes through in her writing on her lifestyle blog Deep Water Happy where she shares tips on everything from sailing to travel to healthy living. She has a self-proclaimed obsession with the outdoors and has sailed the east coast from Maine to the Caribbean. If she is not racing with the St. Augustine Yacht Club, she is teaching ASA sailing courses or she is diving, or running, or cycling. In other words, you can’t stop her.