Planning a holiday to Palau? Take the right sunscreen or you'll be up for a hefty fine.。

The Pacific island nation, an archipelago made up of over 500 islands and home to some of the most stunning coral reefs in the world, will become the very first country in the world to ban sunscreens that are harmful to reefs, BBC reports. 。

It's a whole country ban similar to that imposed by Hawaii, which became the first US state to ban sunscreens deemed harmful to reefs in May.。

Like Hawaii, Palau's ban comes into effect in 2020.。

Palau's government has reportedly signed legislation that restricts the sale of sunscreen products that contain particular chemicals considered harmful to reefs. Anyone caught with these products is looking at a sizeable $1,000 fine.。

A diver investigates a sea fan in the Peleliu Wall, one of the deepest wall dives in Palau.Credit: ullstein bild via Getty Images。

So, what chemicals are we looking at? Hawaii's legislature, for one, focuses on the environmental impacts of two chemicals found in some sunscreens, oxybenzone and octinoxate, and their effect on marine ecosystems — including reefs. 。 According to another report by the。According to another report by the。

BBC。

, these two chemicals alone are used in over 3,500 popular sunscreen products worldwide. 。

Say, haven't we already heard about these chemicals? As we've noted before, the effects of one of the banned chemicals, oxybenzone, on coral reefs proved the cornerstone of a scientific study released in 2015, which sparked global headlines faulting sunscreen for the decline of reefs.。The study, published in the journal,

Archives of Environmental Contamination and Toxicology,

determined the chemical had a detrimental effect on the DNA of coral. 

But many scientists criticised the controlled laboratory conditions of the experiments, and argued that although the chemicals do have a negative effect on the reefs, in the scale of things they have much more serious threats than sunscreen toxins — we're talking ocean acidification and coral bleaching caused by human-induced climate change, and pesticide/waste run-off.。