Coral-damaging sunscreens have been banned across all Thailand’s marine national parks.
The move comes after concerns emerging from tourists that flock to the south east Asian country and use sunscreen that contains chemicals harming corals.
The Thai Department of Conservation said four ingredients commonly found in sun creams were shown to destroy coral larvae, obstruct coral reproduction and cause reef bleaching.
Those lotions containing oxybenzone, octinoxate, 4-methylbenzylidene camphor or butylparaben have been banned, and anyone violating the ban can be fined up to 100,000 baht (£2,100).
The Thai Department of Conservation have not said how they plan to enforce the new rule.
Similar bans have been introduced by the Pacific island of Palau and the US state of Hawaii.