Sunscreen Ingredient Damages Coral Reefs

Coral bleaching is a condition when coral colonies either die suddenly exposing the white skeleton, or lose their green/blue colour so the coral is alive, but in trouble. This condition can be triggered by many factors: Too much grazers, other corals, coral killing bacteria, protozoans, storms breaking and displacing the corals to areas with inaccurate light or currents, hot water... and also chemicals

But what the Dr. Craig Downs and other members of the Haereticus Environmental Laboratory have found is, instead, that the planulae are damaged by chemicals.

A planulae is like a tiny flat slug, (hence its name: Plane = flat, ula = small) swimming freely in the sea. Planulae are wandering "coral babies", not coral reefs. They do not have an skeleton still.

When a planula settles in an appropriate place starts promptly to creating its inner skeleton. As appropriate places are limited, natural mortality in planulae at this phase is very big, with or without chemicals. The problem is that in sunscreen lotion presence it encases itself in its own developping skeleton instead, and die. And this happens even at very low doses of oxybenzone in the water.

So what is the real effect of this?

Unclear, still. We need to pay more attention to the younger colonies. The long term effect of the chemical could be even to increase the diversity in the area.

Let suppose that we wipe some planulae of the population. Lots of empty spaces are available for the other. Fast growing dominant species with small planulae could be taking the majority of the loses. In this case more opportunities will appear for the more delicate slow growing corals, or for species with stronger planulae, or for corals reproducting in winter months. We could have a sucession, without any visible trace of bleaching.

If all species are sensitive, something that we do not know still, eventually we'll have a collapse of the reef for this, but not tomorrow probably. Oxybenzone has been around since 1980 at least and many reefs in heavily populated touristic areas are still here. I'll bet for the "natural" succession theory.

Adult corals could just try to create some resistence. Colonies can live for hundreds or even thousands of years, and they are poisoned by its neighbourgs almost every single day of its long life, with not noticeable harmful effects. They coevolved and are really customed to deal with many types of chemicals.

> Not only did the study determine that a tiny amount of sunscreen is all it takes to begin damaging the delicate corals — the equivalent of a drop of water in a half-dozen Olympic-sized swimming pools — it documented three different ways that the ingredient oxybenzone breaks the coral down, robbing it of life-giving nutrients and turning it ghostly white.