You may come across new “reef friendly” bottles of sunscreen over the summer, often beside a small logo of a coral plant – but what does it mean?
A study published in the Environmental Contamination Toxicology journal in 2015 claimed that some chemicals used in sunblock may be damaging to coral reefs. Two of the most commonly used UV blockers, known as oxybenzone and octinoxate, could cause coral bleaching, it suggested. As a result, last year Palau and Hawaii banned sunblocks containing these ingredients, with Key West in Florida this year following suit, while Mexico also encourages visitors to use "reef-safe" products.
Some brands, including Nivea, Caudalie and REN, have excluded the two chemicals from some of their products, while mineral sunscreen alternatives made by Badger, Earth Mamma or Green People also claim to be reef- or ocean-friendly.
And who wouldn't want to protect coral reefs? The mass bleachings of the Great Barrier Reef – most recently in 2016 – have had a heartbreaking effect on one of Earth's greatest natural treasures. But it is climate change – not sunscreen – and the rising temperature of the water, that is the biggest threat to coral bleaching at a global and regional scale, believes Prof Terry Hughes. As director of the ARC Centre of Excellence for Coral Reef Studies, he has done extensive research on the Great Barrier Reef and has found there is insufficient evidence to prove that sunscreen incurs bleaching. Other marine scientists have echoed this, describing the 2015 study as "misguided".
Dr Louise Allcock, head of zoology at NUIG, says there have been a limited number of studies on the issue. “The jury is probably out a bit on whether sunscreen is damaging to coral reefs,” she says.
But should we be concerned about chemicals in sunblock affecting marine life in Irish waters? “Given our weather and the temperature of the water here, there are far fewer people swimming in the water here to have much impact . . . There are many other things causing pollution that we should probably worry about more,” says Dr Allcock.
“Sunscreen is a huge distraction from the fact that the biggest threat to the ocean is the climate crisis,” she says. “If people want to do one thing that would help coral, they could either cut their car usage – walk, cycle, carshare, take the bus – or eat less meat and dairy. Transport [carbon dioxide] and cows [methane] are responsible for a huge proportion of our greenhouse gas output.”
Well-intentioned people might feel like they’re doing their bit for the environment by using reef-friendly sunscreen instead of thinking about how to tackle bigger, more uncomfortable issues – such as taking fewer flights, for example.
One Change is a weekly column about the changes, big and small, that we can make in our daily lives for the good of the planet