For what cannot be covered by clothing… Use purely mineral-based sunscreens to avoid absorbing harmful chemicals through your skin.
Mineral-based sunscreens work by creating a physical barrier on top of your skin which reflects the sun’s UV radiation away from your body. The minerals, zinc oxide and titanium dioxide are essentially inert and do not chemically react with the skin.
By contrast, chemical sunscreens penetrate into the skin. The chemicals; oxybenzone, avobenzon, octinoxate, homosalate, octisalate, octocrylene, ecamsule, and padimate O… are absorbed into the skin.
Oxybenzone, avobenzone, octocrylene, and ecamsule are all absorbed into the bloodstream. In addition, studies have found oxybenzone not only in the blood, but also in human breast milk, amniotic fluid, and the urine as a result of applying chemical sunscreen onto the skin as directed.
Chemical sunscreens also have associated health risks. Especially hormonally related ones, like; endometriosis in women, and lower testosterone levels and decrease sperm count in males.
So far, based on the evidence, mineral sunscreen is considered safe, while chemical sunscreen is likely a much bigger health concern than people are led to believe.
Chemical sunscreens are also hazardous to reef life, and mineral ones are not.
So what should you do to make a difference? Start using only purely mineral-based sunscreen and educate and encourage others to do the same. Warn others, especially pregnant women and nursing mothers. Suggest local communities ban the sale and use of chemical sunscreen in places where people are wearing sunscreen while swimming, snorkeling and scuba diving around reefs.