In 2019 the FDA published a study that changed everything most people thought they knew about sunscreen. Researchers applied common sunscreen products to volunteers and then tested their blood. After just one single application, six widely used sunscreen chemicals were detected in the bloodstream at levels that exceeded the FDA's own safety threshold.
Those chemicals included oxybenzone, avobenzone, octocrylene, homosalate, octisalate, and octinoxate.
The FDA did not say these chemicals are safe. They said the opposite. They called for more safety data because the existing data was not enough to classify them as safe. Years later that data still has not been provided by the manufacturers.
These are not obscure ingredients. They are in the majority of sunscreens sitting on store shelves right now. They are in the sunscreen you probably used last weekend.