It's summer time in the tropics and it would be great to go out to the beach, ride the waves, and get tanned. Or just soak in cool waters. Of course, we are always admonished to put on sunscreen.
But a recent research has urged legislators to ban the use of sunscreens with chemical ingredients oxybenzone and octinoxate, saying that these can potentially cause coral bleaching and even hormonal imbalances.
For his 2015 study, Downs' lab placed coral larvae, which are just a couple of millimeters long, into the tiny wells of microplates filled with artificially created seawater containing oxybenzone at "environmentally relevant" concentrations measured in parts per million, parts per billion, and parts per trillion. The larvae reacted by losing their cucumber-like shape and turning white, indicative of bleaching.
The methods with which the study was conducted has been met with skepticism however, as the conditions may not reflect a realistic environmental situation wherein these chemicals could somehow make a large impact on corals.
Eric Hochberg says he believes Downs' research offers weak evidence that oxybenzone is actually damaging corals because the experiment's laboratory conditions "completely lack realism." Hochberg is working on his own study by placing corals in tanks with flowing water containing concentrations of oxybenzone that match those found in water samples around Bermuda.
Another thing that may cause some concern with using these sunscreens has to do with their effects on health.
Beyond corals, some scientific evidence has shown that oxybenzone may produce harmful effects in mammals and fish by mimicking estrogen in the body and disrupting the endocrine system, which produces and regulates hormones.
For now, further evidence that would indicate clear environmental detriment might be needed before a widespread ban on sunscreens containing these two ingredients is implemented. Otherwise, we would need to find another way to protect ourselves from the sun.
(Image credit: Bill Branson/Wikimedia Commons)