QWhat do you tell your patients about sunscreen damaging coral reefs?

Richard Winkelmann, DO

Richard Winkelmann, DO

Director for Dermatology and Mohs Surgery
Optum Care
Los Angeles, CA

To date, there are no randomized controlled trials evaluating the effects of sunscreen on the incidence of coral reef bleaching. Yet articles published by Danovaro et al. in 2008 and Downs et al. in 2013 and 2015 received significant media attention and ultimately led to legislation in Hawaii banning use of oxybenzone and octinoxate containing sunscreen products in 2018. This ban on two common organic UV filters has led to the development of marketing strategies suggesting inorganic UV filters are ‘Reef Safe’ without any clearly defined benchmarks of safety.5 Miller et al. contend that there is limited evidence that either organic and inorganic UV filters are hazardous to the environment and it is inaccurate to portray one as better for the environment than the other based on available testing analysis.5

When my patients as about the association of sunscreen and coral reef damage, I start by educating them that ex-vivo studies demonstrating toxicity do not necessarily translate to real life situations. In studying the complex ecosystem of coral reefs and bleaching over the last few decades, stronger factors associated with the presence of human influence than use of sunscreen have had more significant impact. On a large scale, global warming and fossil fuel consumption are leading to a steady increase of sea temperatures with dramatic consequences for coral reef vitality.6 Locally, coral reefs are most strongly affected by the environmental pressures caused by overfishing.7 Therefore, there is consensus among the dermatologic community that based on current scientific data, the evidence for sunscreen use and its negative impact on coral reef bleaching is insufficient. On a regional scale, sunscreen use correlates more with the presence of other human behaviors that are more strongly associated with coral reef damage. However, additional studies are needed to properly characterize the environmental effects of organic and inorganic UV filters.


  1. Danovaro et al. Environ Health Perspect. 2008
  2. Downs et al. Ectotoxicology. 2013
  3. Downs et al. Arch Environ Contam Toxicol. 2015
  4. Hawaii SB2571. 2018
  5. Miller et al. Environ Sci Europe. 2021
  6. IPCC Climate Change. 2015
  7. Burke et al. Reefs at Risk Revisited. 2011