Coral Reefs and ZnO – Balancing hazards versus risks


EverCare, Raleigh, USA


As coral reefs continue to be under the threat of extinction, there is a renewed interest in understanding the direct impact humans have on coral reefs. Of particular attention has been the environmental impact of UV filters used in sunscreens. This has led to recent legislation prohibiting the use of some filters which are thought to cause long term damage to coral reefs. As regulations continue to restrict the use of sunscreen ingredients, attention has begun to focus on zinc oxide (ZnO) as the UV filter of choice when developing reef-friendly sunscreens. A risk assessment of ZnO shows the use of ZnO as a sunscreen active ingredient is not predicted to lead to increased environmental risks to corals.

Covering less than 1% of the Earth’s surface, coral reefs make up some of the most diverse ecosystems in the world supporting roughly 25% of all marine species. Beyond housing some of nature’s most colorfully abundant species, over half a billion people benefit from coral reefs as a source of food supply, as coastal barrier for habitat and agriculture, and through a vibrant tourism industry (1). Coral reefs play a key role in protecting coastal land and beaches by minimizing shoreline erosion. Their structures act as natural breakwaters, buffering up to 97% of a waves impact preventing flooding and damages from inclement weather (2). Additionally, coral reefs are home to species that offer pharmaceuticals to treat illness and disease.


Unfortunately, corals are dying at an extremely fast rate with climate change being cited as the biggest threat to coral reefs. Particularly, rising temperatures at the seas surface correlate directly to significant mass bleaching events that stretch hundreds of kilometers or more (3).  When ocean waters sustain higher temperatures for a prolonged time, corals experience ...