Concern about the impact of sunscreen on coral reefs has been growing since 2008 when the first study was published showing a direct link between coral mortality and ingredients found in sunscreens, especially in areas with high levels of tourism. The scale of the problem is significant. Scientists estimate that between 6,000 and 14,000 tons of sunscreen—the equivalent of 25 to 60 million bottles—wash off of snorkelers and swimmers into coral reef environments each year. At the same time, ocean and coastal tourism is growing, and it is estimated that more than a billion people worldwide will be visiting oceans for recreation and tourism by 2020.
Since that initial study, many more studies have followed and have identified two chemicals found in sunscreens that cause direct harm to corals: oxybenzone and octinoxate. Beyond sunscreen, these ingredients are found in lipsticks, moisturizers, and other cosmetics, and they are readily absorbed into the blood (and subsequently found in human urine). All products containing these chemicals, not just sunscreens, should be avoided when you are near marine environments. In fact, some experts believe that the wash-off of these chemicals during showering and swimming plays a bigger role than climate change in damaging coral reefs. While oxybenzone and octinoxate are the most well-studied culprits, new research is finding that other chemicals in sunscreens may also be harmful to coral reefs, in particular octocrylene, 4-MBC, benzophenone-3, methoxycinnamate and butylparaben. Here is a vetted list of all of the known pollutants that may be in your sunscreens and other skin/hair care products that should be avoided.
As snorkelers, divers, and part of the community of people who wish to protect coral reefs, we need to educate ourselves about all the ways in which we can reduce our impact on these diverse and productive ecosystems. While the recent bans of certain sunscreens in Hawaii and in other places are a step in the right direction, and will help reduce the prevalence of “non-coral friendly” sunscreens in areas with high volumes of tourism, this alone is not enough.
So the question most of us will want to know the answer to is: “What can I do?”
To begin to answer this, we’ve put together the following recommendations for reef-safe sun protection, as part of our larger effort to build ocean-friendly behaviors—Blue Habits—among nature travelers.
First, it is important to acknowledge that protecting yourself from ultraviolet solar radiation, a well-known risk factor for skin cancer is very important. Snorkelers and divers should take measures to reduce their risk, and sunscreen does serve as an important tool in that effort. Our recommendations:
The best thing that snorkelers and divers can do is to first reduce their need to use sunscreen by covering up. Wearing rash guards, dive skins and wetsuits, as well as using hats, sunglasses, and sun Buffs will all help to reduce the amount of area of your body you need to apply sunscreen to, and thus reduce the amount of sunscreen you need to apply. Some companies also rate their clothing with an Ultraviolet Protection Factor, or UPF, similar to sunscreens’ SPF numbers. Clothing is considered as effective as sunscreen on the parts of the body it covers.
When you do need to use sunscreen, or for areas that can’t be effectively covered with clothing, be aware that there are two types of sunscreen to choose from:
* It is important to note that you should use mineral sunblocks that are “non-nano” in size, because mineral sunblocks that have particle size below 100 nanometers can be ingested by corals.
As a consumer you should also try to stay up-to-date with the latest developments related to sunscreen research. The ban of certain sunscreens in Hawaii along with the new research showing the harmful impacts of current sunscreen products on corals is leading companies to develop new sunscreen products. As these new products come on to the market, the more you know about them and the more you support them through your purchases, the more likely we will be start having more truly “reef safe” products available to us.
To learn more about the products you might be using that could harm coral reefs here is a list of nearly 600 sunscreens sold in the U.S. that contain oxybenzone, including products by Hawaiian Tropic, Coppertone, and Banana Boat, as well as 172 facial moisturizers, 111 lip balms, and 81 different types of lipstick.
You can read more about the issue of sunscreen and coral reefs through the following articles:
Beyond our recommendations for reef safe sun protection, there are a number of ways that you can reduce your impacts on ocean health in your daily life and during your travels. For more information about other ways to contribute to healthy oceans through your consumer choices, sign up for updates from our Blue Habits Program, which aims to help people live more ocean-friendly lives.
Wayne Sentman is our director of conservation travel programs and an Oceanic Society naturalist since 1998. He is an experienced guide with a diverse background in marine mammal, seabird, and marine debris research. Wayne also co-teaches undergraduate field programs in Kenya on human-wildlife conflict and on the use of social media and art to raise public participation in conservation. He recently received a Master's in Environmental Management from Harvard University.