After 2 hours, sunscreen that includes zinc oxide loses effectiveness, becomes toxic: study

[Still Waters]

Sunscreen that includes zinc oxide, a common ingredient, loses much of its effectiveness and becomes toxic after two hours of exposure to ultraviolet radiation, according to a collaboration that included Oregon State University scientists.

The toxicity analysis involved zebrafish, which share a remarkable similarity to humans at the molecular, genetic and cellular levels, meaning many zebrafish studies are immediately relevant to people.

Findings were published today in Photochemical & Photobiological Sciences.

The research team, which included College of Agriculture Sciences faculty Robyn Tanguay and Lisa Truong and graduate fellow Claudia Santillan, sought to answer important but largely neglected questions regarding the massive global sunscreen market, predicted by market data firm Statista to be worth more than $24 billion by the end of the decade.

https://phys.org/news/2021-10-hours-sunscreen-zinc-oxide-effectiveness.html

https://link.springer.com/article/10.1007%2Fs43630-021-00101-2

[+joc]

I've worked outside in the sun for thirty years...never put on any sunscreen...never had any problems...plus...I've got a hell of a tan!