A recent study by a large team of scientists from multiple nations has revealed that sunscreen may be a significant factor contributing to coral bleaching.

Among most beachgoers, sunscreen is seen as a necessity before any outdoor activity.

Especially in certain areas with dangerously high UV radiation rates, not applying it may be seen as a health hazard by many.

In fact, in countries such as Australia, a lack of sunscreen use can contribute to skin cancer.

Something as common as sunscreen being correlated with coral bleaching may seem ludicrous to many.

However, a study shows that certain chemicals and the specific makeup of certain sunscreen brands are indeed causing coral degradation.

Specifically, the chemicals oxybenzone, octinoxate, and octocrylene are all those that can be absorbed by corals, causing bleaching.

This research shows that these chemicals are designed for humans to absorb light energy and dissipate it into heat, preventing sunburn.

However, when they are washed off into the water and absorbed by corals, they are metabolized in such a manner that turns sunlight toxic.

This subsequently results in the symbiotic algae dying, causing coral bleaching.

It is not only chemicals that pose a threat to corals; however, any sunscreen with nanoparticles in it, particles not exceeding 100 nanometers, may cause coral degradation as well.

The study shows that these nanoparticles can be absorbed by corals, interfering with the symbiotic activities between corals and other organisms.

Long-term exposure to the nanoparticles leads to coral bleaching, a result not unsimilar to the chemical threats.

The findings suggest that around 10 percent of world oceans are vulnerable to this threat posed by sunscreen, most likely due to the popularity of beaches among tourists.

To combat this, many vacation spots are implementing a ban on harmful sunscreen brands.

Hawaii was the first to do so in 2018, and these policies only allow “reef-safe” sunscreen to be sold in these areas.

Some other beaches that also have this rule in place are the U.S. Virgin Islands, Palau, and certain parts of Mexico.

This is all done to promote sustainable tourism and ensure the longevity of native corals.

The enforcement of these policies is significant for these areas as tourism is a main source of revenue.

In Hawaii, for example, around 21 percent of the state’s economy revolves around tourism, with its beautiful beaches and colorful corals being a major selling point.

The loss of color in these corals and the degradation of these beaches may result in significant economic repercussions.

The same can be said for many coastal cities that also take pride in their marine life.

Thus, promoting and enforcing the use of “reef-safe” sunscreen is being taken quite seriously, with all supermarkets and shops not being allowed to sell sunscreens with toxic chemicals.

Of course, this does not account for the tourists who often pack their sunscreen, which cannot be individually vetted upon entry.

In this regard, spreading the knowledge that certain chemicals can indeed cause coral loss is crucial, encouraging people to avoid certain brands of sunscreen.

Jonathan Moon
Grade 10
Singapore American School