The majority of the world’s coral reefs are projected to be lost due to climate change. This isn’t something that will happen in 50 or 100 years but in the very near future.
The deterioration is caused by ocean warming, ocean acidification and extreme storms.
In short, it’s caused by climate change.
We need to act urgently to reduce greenhouse gas emissions to protect our precious coral reef systems.
However, contaminants like pesticides, medicines and nutrient runoff from agriculture also contribute to reef degradation.
Solutions to these issues need to be addressed in parallel to tackling climate change.
But what about sunscreen? Does sunscreen damage coral reefs? Should we be using reef safe sunscreen or maybe stop using sunscreen altogether?
Reef Safe Sunscreen
You may have read media reports or blog posts stating that sunscreen is killing reefs and that we should use sunscreen that is free from certain chemicals like benzophene-3 and octinoxate.
There seems to be a lot of misinformation around coral reef degradation, in particular coral bleaching, and its relationship with sunscreen.
So let’s take a look at the latest science from the experts.
Does sunscreen cause coral bleaching? The answer is no, according to research by Nial Wheate from the University of Sydney.
… while chemicals in sunscreen pose a risk to corals under laboratory conditions, they are only found at very low levels in real world environments.
This is a view is shared by Professor Terry Hughes, a leading scientist who specialises in the impact of climate change on coral reef ecosystems.
The environmental concerns over sunscreens on coral reefs are centred overwhelmingly on just two studies. […] Experiments that expose corals to sunscreen chemicals typically use far higher concentrations than have ever been measured on an actual reef. […] coral bleaching at a global and regional scale is caused by anthropogenic heating, not sunscreen.
How do I know Professor Terry Hughes is an expert in the field? You can read about his qualifications and research, view his Google Scholar profile here and for easier reading, articles published at The Conversation.
Another recent report concluded that the reef safe sunscreen market is unregulated and not scientifically justified.
However, research is ongoing and a report by the National Academies will be published later in 2022.
I came across a recent Twitter thread discussing this issue. It’s worth reading to understand the different viewpoints.
The Precautionary Principle
If sunscreen poses a limited risk to corals, why have Hawaii, Palau and other jurisdictions banned their use?
The precautionary principle states that if there is a risk of environmental harm, action should be taken to prevent harm, even in the absence of scientific proof.
Basically, this means that action should be taken, just in case.
In many regions of the world, coral reefs are essential to livelihoods. Reefs provide food, employment, fishing industries, tourism benefits and protection from coastal erosion.
Coral reefs are experiencing devastating bleaching events and ongoing degradation.
A while back, I wrote a report on the Pacific Island of Tonga that discusses the dire consequences of climate change on their reefs and livelihoods.
The situation is grim and the impacts of climate change are being observed now, not in the future.
The condition of reefs in small island nations like Tonga and Palau is especially concerning when you consider the significance of reefs within their entire economy.
If a reef is destroyed, they lose a primary source of food, fishing and tourism industries.
In these small nations, there are few other economic activities to make up for the loss. Many will be left with no choice but to leave their homes and migrate elsewhere.
Whereas in larger economies, like Australia for example, if the Great Barrier Reef dies, there are many other industries that will continue to provide jobs and resources. It will have an impact of course, but the loss of the reef alone won’t devastate the broader economy.
It’s understandable that people want to act to protect an invaluable ecosystem. For many reef-reliant nations and regions, any and every action should be taken to prevent further decline.
That is why some places are banning sunscreen.
But does swimming or showering near reefs while wearing sunscreen pose a risk of environmental harm? Current evidence suggests there is no bleaching risk from sunscreen.
Should you avoid sunscreen anyway?
If you live in or are visiting a place where sunscreen is banned then of course you should adhere to the law and local regulations.
But don’t forget that skin cancer is a major health risk, especially after repeated exposure and sunburn.
Skin cancer is the most common cancer around the world, including in the United States. The use of sunscreen significantly reduces the risk of skin cancer as well as skin ageing. You can read all the facts about sunscreen here.
By not wearing sunscreen, you’re placing yourself at increased risk of skin damage and cancer. Yes, you can wear protective clothing, hats and sunglasses but exposed skin should be protected with sunscreen.
If you feel like you can’t wear sunscreen or if you’re in an area where it has been banned, I recommend swimming at dawn or dusk, when sun exposure is limited. Alternatively, avoid swimming and choose other activities instead.
Are Reef Safe Sunscreens Greenwashing?
There is no official FDA definition or criteria as to what makes a sunscreen ‘reef-safe’. Up to 48% of sunscreens labelled as reef-safe do not meet NOAA criteria and 4% do not meet legislative criteria.
Consumers are purchasing these items for their perceived lower environmental impact when that is possibly inaccurate or misleading.
Additionally, reef-safe sunscreens are typically more expensive than regular sunscreens and potentially offer no additional benefit.
Marketing products as reef safe is a classic example of greenwashing.
How do we protect coral reefs?
At this point in time, the world has warmed by 1.25°C above pre-industrial levels. Coral reefs are unlikely to survive at 1.5°C of warming and it’s virtually impossible that any will survive at 2°C.
The chances are about 50/50 that we can keep warming to 1.5°C.
We must urgently act to end our use of fossil fuels and limit all greenhouse gas emissions including carbon dioxide, methane and nitrous oxide and prevent further deforestation.
A general overview of what we can do as individuals and households is outlined in my guide to being sustainable at home. Or you can read the scientific reports listed below for detailed data and sources.
IPCC. (2018). Summary for Policymakers. In: Global Warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty [Masson-Delmotte, V., P. Zhai, H.-O. P.rtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. P.an, R. Pidcock, S. Connors, J.B.R. Matthews, Y. Chen, X. Zhou, M.I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, and T. Waterfield (eds.)]. In Press.
IPCC. (2019). Summary for Policymakers. In: IPCC Special Report on the Ocean and Cryosphere in a Changing Climate [H.-O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, M. Tignor, E. Poloczanska, K. Mintenbeck, A. Alegría, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.)]. In press.
IPCC. (2022) Summary for Policymakers. In: Climate Change 2022: Mitigation of Climate Change. Contribution of Working Group III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [P.R. Shukla, J. Skea, R. Slade, A. Al Khourdajie, R. van Diemen, D. McCollum, M. Pathak, S. Some, P. Vyas, R. Fradera, M. Belkacemi, A. Hasija, G. Lisboa, S. Luz, J. Malley, (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA.
Matthews, H. D., & Wynes, S. (2022). Current global efforts are insufficient to limit warming to 1.5°C. Science, 376(6600), 1404-1409.
Tsatalis, J., Burroway, B., & Bray, F. (2020). Evaluation of “reef safe” sunscreens: labeling and cost implications for consumers. Journal of the American Academy of Dermatology, 82(4), 1015-1017.
Wheate, N. J. (2022). A review of environmental contamination and potential health impacts on aquatic life from the active chemicals in sunscreen formulations. Australian Journal of Chemistry, 75(4), 241-248.