It’s been estimated that, each year, 4,000-6,000 metric tons of sunscreen comes off of ocean-swimmers and subsequently threatens up to 10% of the world’s corals. Whoa!
Four commonly found sunscreen ingredients can awaken dormant viruses in the symbiotic algae called zooxanthellae that live inside reef-building coral species.
The chemicals cause the viruses to replicate until their algae hosts explode, spilling viruses into the surrounding seawater, where they can infect neighboring coral communities.
Zooxanthellae provide coral with food energy through photosynthesis and contribute to the organisms’ vibrant color. Without them, the coral “bleaches”—turns white—and dies.