A Swiss scientist, Dr. Karl Fent concluded that the hormones of fish were affected by suncreens. Again, the culprit was the organic UV filter, 3BC (3-benzylidene camphor).
I kept looking for other studies. These chemical UV filters mimic estrogen and may cause hypothyroidism in humans. Pregnant women need to be especially concerned.
My mind returns to the scene that I watched on the documentary. Millions of visitors, each armed with a bottle or tube of sunscreen. All being washed into the sea and accumulating.
It’s clear that these UV filters are effective against sun damage to the skin but are there safer alternatives that don’t kill coral and disrupt hormones in aquatic life? In the report, they showed a resort in Mexico which prohibits the use of sunscreens with UV filters. Visitors swim with dolphins and enjoy the natural setting. Workers check bags and signs are posted showing “No Sunscreen”. When told, most visitors thought it was a great idea and handed over their bottles and tubes in favor of the sunscreen provided by the resort, one which didn’t contain the chemical UV filters.
Chemical UV filters work by absorbing UV rays from the sun. Another option is a sunscreen that blocks or creates a physical barrier thereby protecting the skin. So called mineral sunscreens. The safest mineral option as recommended by the Environmental Working Group report on the best sunscreens is a formula made with zinc oxide.
A Couple of Chemical UV filters to avoid due to hormone disruption:
4-methyl benzylidene camphor (4-MBC)