Protecting your skin from harmful sun exposure has become almost second nature, and that includes applying sunscreen when you visit your local beach or take that snorkelling trip on your dream tropical adventure. But have you ever stopped to think about what impact sunscreens might be having on the world’s fragile marine environments? Here, we’ll describe how some sunscreens could be harming coral reefs and what ingredients to look out for when choosing a ‘reef-friendly’ sunscreen.

How are sunscreens harming coral reefs?

The active ingredients in sunscreens that protect your skin from the sun’s damaging ultraviolet (UV) radiation are called UV filters. These UV filters are classified as chemical (organic) or mineral (inorganic or physical) filters based on the way they work to protect your skin. Chemical UV filters actively absorb UV radiation, while mineral UV filters can also reflect and scatter UV radiation.

When you apply sunscreen to your skin, it doesn’t stay there forever. It can be washed off when you go for a swim in the ocean or can end up in wastewater from your shower that eventually makes its way to the ocean.

Over the past decade, scientists have detected the presence of certain chemical UV filters in marine environments, particularly in coastal areas where there are lots of people swimming or spending time at the beach near the water. While the exact amount of UV filters that enter the ocean from sunscreen residue is unknown, estimates suggest that a whopping 4000 to 14,000 tons of sunscreen washes off people into the ocean every year.

The presence of these chemical UV filters in marine environments is concerning because they are suspected of harming coral reefs. Certain chemical UV filters have been shown to cause coral bleaching – a stark warning sign of distress and poor health in corals – as well as interfere with how coral reproduce and grow.

Sunscreen ingredients

While there are a number of sunscreen ingredients that may have the potential to impact coral reefs and other marine life, there are two chemical UV filters that are currently of interest: oxybenzone and octinoxate, which are the main active ingredient in an estimated 70% to 80% of sunscreens.

Findings from studies that demonstrate effects of oxybenzone and octinoxate exposure on coral have led to certain countries banning the sale of products that contain these UV filters. This ban was first introduced in Hawaii in 2018 and came into effect in January 2021, but similar laws banning these UV filters are being implemented or discussed in other parts of the world, although not yet in Australia.

While the mineral UV filters zinc oxide and titanium dioxide are considered safer options for marine environments, covering up with sun protective clothing is the safest way to protect coral reefs AND your skin.

Choosing reef-friendly sunscreens

It’s important to always protect your skin from sun damage caused by exposure to harmful UV radiation. It’s also important to know that not all sunscreens are harmful to coral reefs. But what should you look out for when you are choosing a reef-friendly sunscreen for your next beach afternoon or island getaway?

Avoid products that contain chemical UV filters associated with harming coral reefs and choose octinoxate- and oxybenzone-free sunscreen products. Look for mineral sunscreens that contain the UV filters zinc oxide or titanium dioxide, opting for formulations that don’t use nanoparticles, which are considered safer for marine environments. If you are travelling, remember to check whether there are any local rules or regulations in place to guide your sunscreen selection.

Whatever sunscreen you choose, think about whether a cream or lotion could be more suitable than an aerosol or spray formulation. Why? Creams and lotions can be applied evenly to the skin for full and effective coverage. This can sometimes be difficult to achieve with a spray in windy conditions like at the beach.

Other important measures you should take to help protect both your skin and our marine environments are to cover larger areas of your exposed skin with clothing or swimwear that contains UV protection and to stay in the shade during the times when UV radiation is at its greatest.

Looking for a mineral sunscreen to help protect both your skin and coral reefs? All INVISIBLE ZINC sunscreens contain naturally-sourced micronised zinc oxide as the only active ingredient, providing high SPF broad spectrum protection against UVA plus UVB radiation in a reef-friendly sunscreen.

Frequently asked questions about reef-friendly sunscreen


Certain chemical UV filters have been banned under the Hawaii Reef Bill. ‘Reef-friendly’ sunscreen products do not contain these ingredients.


Only certain chemical UV filters have been shown to cause harm to coral reefs and other marine life, or to accumulate in oceans in toxic amounts. You can check the label of your sunscreen to see which ingredients it contains.


Mineral sunscreens that contain the UV filters zinc oxide or titanium dioxide are usually considered reef-friendly and are preferred in areas where certain chemical UV filters are banned.