“This article may contain affiliate links. If you decide to make a purchase, we will make a small commission at no extra cost to you.”

Harmful Ingredients In Sunscreen – Ocean Safe Sun Care Products Guide

Coral reefs are in danger all over the world and besides global warming and rising sea temperatures, harmful ingredients in sunscreen have significant impact on the marine life too. Most common sunblock contain chemicals such as oxybenzone, octinoxate and avobenzone. These are proven to cause coral bleaching, moreover can be dangerous for the human’s body too. For your own safety and to preserve the sensitive underwater ecosystems, make sure to choose eco-friendly sun protection products. In this guide we explain what ingredients you should avoid and what are safe to use.

Anett Szaszi - Snorkel Around The World

Written by Anett Szaszi

Anett is a certified scuba diver, freediver, and an expert in snorkeling with more than 10 years of experience. She fell in love with the ocean while snorkeling in the Red Sea on a vacation to Egypt back in 2008. Since then, she has been traveling to discover the world’s best snorkeling spots and sharing her experience and tips to inspire others. Find her photos on @anett.szaszi Instagram too!

Why is it important to use ocean safe sunscreen

The whole world relies on coral reefs for various reasons like coastal protection, food or livelihood. They are the most diverse and oldest ecosystems providing home to thousands of different marine species.

Although corals seem to be extremely resilient to climate changes, the threats to reefs are bigger than ever before. Coral reef dangers are mostly human-related activities like carbon emissions, over-fishing, coastal runoff, plastic pollution, and chemicals effects that include sunscreens too.

Most harmful ingredients in sunscreen are already prohibited in several places worldwide. The Hawaii sunscreen ban was a breakthrough that restricts using chemical sunscreen from 2021 followed by many other countries such as Mexico, Palau and Boaire.

How does sunscreen affect coral reefs and humans

You might ask how that little tube of sunscreen causes such a bad damage on the reefs but knowing that an estimated 8-14.000 tons of sunscreen enter the world oceans annually, the danger is beyond doubt. It is proven that common sunscreen ingredients like oxybenzone and octinoxate are responsible for DNA deformities and coral bleaching.

Moreover, dangerous sunscreen ingredients are not only harmful to the environment but also for your skin. Common sunscreen chemicals may cause severe allergic reactions and hormone disruption according to EWG. By using reef safe sunscreen for snorkeling and other water activities, you protect your body and the ocean at the same time.

Tip: Our best recommendation is to cover your body with uv protective clothing on land and while snorkeling too. Like this, you can skip or at least minimize your sunscreen usage and leave less impact on nature. To protect the uncovered areas, choose a product that is truly ocean friendly! Here is our best reef safe sunscreen list!

Harmful ingredients in sunscreen

Unfortunately, there is no proper regulation for „green” or „natural” and some products are not as advertised despite the pretty Safe labels. The best advice is: always read the ingredients list before buying a cosmetic product! Here is a little guide on the dangerous ingredients to avoid:

Reef Safe Sunscreen Buying guide

Oxybenzone (Benzophenone-3)

A general component of sunscreen that provides broad-spectrum UV rays coverage. It is toxic to coral larva especially to juveniles by disrupting the symbiosis between the coral and algae. As an irritant, it can cause allergies and by penetrating the skin it results in chemicals circulation in the bloodstream (97 % of the American have oxybenzone in their body), moreover it is listed as a direct cause of coral bleaching by scientists


Commonly used UV filter. It is absorbed through the skin and can mimic hormones. Oestrogen hormone increase, thyroid fluctuation, and reproductive system diseases are the most common mentioned risks of using sun care products that contain octinoxate.

Human urine, blood and breast milk might contain oxtinoxate, showing that it is systematically absorbed. Besides being an endocrine disruptor, it is linked to coral bleaching even at very low concentration.


Parabens are preservatives to prevent the growth of bacteria, yeast, and molds and about 85% of the products contain them. Parabens like propyl, methyl or butylparaben can mimic the hormone estrogen which might contribute to breast cancer. Always buy Paraben free products!


Often used instead of Oxybenzone but not different from it! It works as Oxybenzone, can penetrate the skin and increases risk of cancer.

SLS and SLES (Sodium Laureth Sulfate and Sodium Lauryl)

Well-known enemies that are still widely used despite their proven irritating effects. SLS is an emulsifier that makes shampoos, body washes and detergents to foam. Although SLS is derived from coconuts,’ it is not natural. Can cause irritation and also toxic to aquatic organism.


Nanomaterials are microparticles with the diameter of 1 to 100 nanometers. Due to this small size, they penetrate the skin and might harm the DNA. Although nanoparticles are important in the energy industry, they are dangerous and linked to produce free radicals.


Microbeads are those tiny plastic particles that you find in scrubs, exfoliants, but also in toothpaste. Because of their small size, most wastewater treatment plants cannot filter these them and they end up in the ocean, at the end in fish and in other aquatic species.

Nano Zinc

Zinc is found naturally in the environment and in seawater. And you might say that many zinc-based sunscreens are promoted to be safe-to-use even for kids. That’s correct, mineral sunscreens don’t cause coral bleaching but recent studies prove that nano zinc oxide caused disorders in sea life.


Silicone-based ingredients soften the skin and smooth hair but mean a potential danger if bioaccumulates in human body or in aquatic organisms.


Formaldehyde is a human carcinogen. You won’t find it in the ingredients list, but certain preservatives used as paraben replacements like Diazolidinyl, Quaternium-15urea, DMDM Hydantoin etc… release formaldehyde.


Used as UV absorber that helps sunscreen ingredients penetrate your skin. It bio-accumulates in the body faster than it can be eliminated. Generally speaking it is hormone disrupter.


A synthetic UV absorber and SPF (Sun Protection Factor) booster. It may cause allergic reactions on sensitive skin.


A very effective, broad antimicrobial ingredient preservative. Even in low concentration classified as a skin and eye irritant.


Commonly found in synthetic fragrances. High levels can cause sluggish sperm and low testosterone levels in adult males. Moreover, phthalates classified as endocrine disruptors that can interfere with normal brain function.

Retinyl Palmitate

Composed of palmitic acid and retinol (Vitamin A). If applied to the skin in sunlight, retinol breaks down producing free radicals resulting higher chance for skin tumors.

Safe sunscreen ingredients

Ocean-friendly sunscreens contain mineral UV filters Zinc oxide and/or Titanium dioxide instead of chemicals. Mineral sunscreen does not penetrate the skin but builds a layer that reflects UV rays like a mirror.

Sunscreens with mineral ingredients provide strong UV protection with fewer health concerns. EWG also recommends Zinc Oxide containing sun lotions as reef safe sunscreen brands for snorkeling, diving or beach activities.

Adding mineral UV filter to a sun lotion is just half of the solution. The best reef safe sunscreen are biodegradable, non-nano and provide broad spectrum protection.

What is a biodegradable sunscreen

Biodegradable sunscreen breaks down in the environment naturally, does not contain harmful ingredients linked to coral bleaching and safe for aquatic ecosystems. The fact is that there is no official ocean-safe certification and sadly, many products are advertised safe, but in fact, they are not.

Stream2Sea Reef Safe Sport Mineral Sun Lotion

  • broad spectrum biodegradable sunscreen with powerful antioxidants
  • fast absorbing, ocean safe formula, made in USA
  • sweat resistant and waterproof up to 80 minutes

Most companies test biodegradability in wastewater treatment facilities only, but some products (for example Stream2Sea sunscreen) are proven to be biodegradable not only in freshwater but in salt water too.

Why are nanoparticles bad in sunscreen

The biggest health concern regarding nano parts is that they can get into the body via penetration or inhalation, but scientists did not prove harmful effects yet.

Although nano Zinc oxide or Titanium dioxide are not considered to cause health issues by human but still considered as harmful ingredients in sunscreen because can be ingested by corals and fish resulting disorders, that’s why you should buy only non-nano sunscreen!

What is broad spectrum sunscreen

Broad spectrum sunscreen means that it provides protection not only from UVB rays but from UVA rays too. Non-broad spectrum products offer protection only from UVB rays that are responsible for sunburn but this is just a half solution.

UVA rays reach the deeper layers of the skin causing cellular level damage on elastin and collagen fibers that leads to aging and wrinkles. Stream2Sea biodegradable sunscreen products exceed FDA’s requirements (US Food and Drug Administration) meaning feature both UVB and UVB protection.

Titanium dioxide vs Zinc oxide – Which is better?

Mineral sun protection products contain Titanium Dioxide or Zinc oxide or both as active physical ingredient. As mentioned, they don’t penetrate the skin but stay on its surface working like a mirror that reflects light.

Generally, Zinc oxide offers a better protection. It is more effective against long-wave UVA rays than Titanium dioxide. Moreover, it is noncomedogenic and antimicrobial.

Titanium Dioxide blocks UVB but not the full spectrum of UVA rays. It can be a good choice for those who cannot use Zinc containing products due to allergy. Moreover, products with titanium Dioxide can be good for those have oily skin because it is known to be less greasy.

Note: Sensitivity tests are recommended before applying mineral sunscreen on the whole body.

Does mineral sunscreen leave a white cast

The most common negative feedback on mineral sunscreen without nanoparticles is the whitish layer that it leaves on the skin. A mineral sun protection product that is really ocean-friendly contains non-nano active ingredients and provide you with a physical protection against the sun. Technically it means that it creates a layer on your skin, and therefore leaves a white residue.

To avoid this and make the product more-user-friendly, companies often use nano nano zinc or titanium dioxide. This can minimize the whitening effect but at the same time, it is not safe for corals. When buying a reef safe sunscreen search the non-nano label on it. This guarantees that the mineral ingredients are safe for corals and the ocean.

If you learn how to apply your mineral sunscreen, the white effect isn’t be so bad but will make you satisfied you chose an eco-friendly solution.

How to apply mineral sunscreen

Mineral sun care products work physically which means you should cover the skin to get protection. With this in mind, you can see the whitening effect as a benefit since you will always know where you applied enough sun lotion and where you need more. Zinc oxide sunscreen might feel dry compared to a classic one.

Our trick is putting some light hydration cream on your skin first, then squeeze a small amount of sunscreen on the palm of your hand, spread it on the areas you want to cover and rub in until you get a thin but continuous coverage.

Don’t worry, if you rub in the sunscreen thoroughly the white effect will fade in about 15 minutes. Remember to reapply it every 40-80 minutes depending on your activity and according to the product instructions.

Is spray sunscreen bad for the environment

It became a trend lately to choose sunscreen aerosols because of the easy application but scientists and organizations do not recommend them. These are the main reasons why you should avoid spray sunscreens and choose lotion or paste form:

  • studies prove that only about 30% of the recommended amount of sun protection used when applying aerosol resulting inadequate
  • bigger concern is that you might inhale the tiny particles which is even more dangerous than penetration of the bad sunscreen ingredients through the skin
  • spray sunscreen might be flammable (although sunscreen itself not flammable, chemicals used in sprays like alcohol, propane, hydrocarbons, etc… are, just think about hairsprays)

Inspired? Pin it!

Sunscreen ingredients guide

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *