Use of ochre in Sub-Saharan African societies is first documented. Today societies like the Xhosa people in South Africa and the Himba and Ovahimba people in Namibia continue to use ochre as protection against the sun.

Ancient Egyptians use rice bran, jasmine, and lupine as a cosmetic sunscreen. To them, light skin was more desirable, and the applied mixture lessened the tanning effects of the sun.

The first documented use of zinc oxide for the treatment of open wounds. It was also used as protection from sunburns.

Burmese women make a sun-protecting paste called thanaka using the bark of the Limonia acidissima tree.

Native Americans use sunflower oil, wallflowers, or pine needles. The Makah and Hesquiat use pine needles from the western hemlock, the Haisla, Hanaksiala, and Kwakiutl use black cottonwood, and the Cahuilla use the pinyon tree. The Zuni ground up the western wallflower plant and northeast tribes use sunflower oil.

The Sama-Bajau nomadic people of the Indo Pacific islands use a sun-protecting paste made from grinding water reeds, rice, and spices.

Dr. Hammer of Germany creates the first sunscreen developed to protect against UV exposure, a salve of quinine. Hammer bases his ointment on studies conducted by Widmark that showed acidified quinine sulfate absorbed UV rays. 

In Germany, chemists B. König and Stanisław Kostanecki synthesize oxybenzone, also known as benzophenone-3. It is a naturally occurring compound in some flowering plants.  

Dr. Unna develops sunscreen from chestnut extract, sold under name “Zeozon” and “Ultrazeozon.” It is a thick paste and is later used by German troops in WWII.

Famed photochemist Josef Maria Eder of Vienna appoints radiologist Leopold Freund as a lecturer in industrial hygiene to study occupational diseases among professional photographers. Together, the two develop an effective UVA/UVB sunscreen called “Antilux.”

Academics often refer to the “first commercial chemical sunscreen” that appeared on the market in 1928 in the United States. It was an emulsion containing benzyl salicylate and benzyl cinnamate. Very little else is known about this first sunscreen. 

HA Milton Blake of Australia develops “sunburn cream” from his boarding house kitchen and creates his company Hamilton. The active ingredient is 10% phenyl salicylate or “salol.” 

Cosmetics manufacturer Drugofa, a subsidiary of the Leverkusen Bayer Group, develop their Delial ointment. It is the first commercialized sunscreen in Germany and contains benzimidazole sulfonic acid.

Swiss chemist Franz Greiter gets a sunburn while climbing Mt. Piz Buin, which inspires the creation of the first “modern” sunscreen. He and his wife Marga begin developing a sunscreen product.

Chemists Stephen Rothman and Jack Rubin describe para-aminobenzoic acid, a controversial chemical that will be used in some of the second-generation sunscreens.

The Army Air Force asks the American Medical Association Council of Pharmacy and Chemistry to start a “top secret experiment” studying substances to prevent sun burns. They find dark red veterinary petroleum (aka “red vet pet”) is the best paste for protection. This paste is soon dispatched in military survival kits supplied to soldiers in combat, however it is both thick and smells bad.

Following Franz’s sunburn on Piz Buin, Franz and Marga Greiter develop a skin cream. They begin selling it under the name “Gletsher Crème” and start company Piz Buin.

Oxybenzone is first discovered to have sun absorbing properties by manufacturing company General Aniline & Film (GAF) Corp. Later we will come to find that oxybenzone is one of the most environmentally toxic active ingredients in commercially produced sunscreens. 

Greiter invents the SPF rating system, which stands for Sun Protection Factor. SPF measures protection against UVB exposure.

Prior to 1977 it was understood that UVB rays burned the skin, but other damage caused by UVA rays was overlooked. Due to the desire for sun-tanned, rather than burned skin, most skin protection focused on UVB protection.

The US Food and Drug Administration (FDA) begins regulating sunscreens with a focus on UVB protection. They adopt the UVB measure SPF as an appropriate indicator for sunscreen effectiveness. Fourteen UV filters are initially approved, including oxybenzone. 

A study shows exposure to para-aminobenzoic acid causes damage to human DNA. It also becomes apparent that it can cause allergic reactions which leads to its removal from many sunscreens. Due to public outcry brands begin to remove PABA from their lotion, however, it isn’t until 2019 that the FDA bans the use of PABA.

Use in sunscreen propels the chemical to be added to the US High Production Volume Challenge Program list, meaning it has hit a manufactured amount and importation amount of one million pounds per year. Oxybenzone is clear, odorless, and broad spectrum, making it one of the most attractive active ingredients to consumers. It also has some UVA protection, which is a rarity in US approved sunscreen ingredients.

Scientists begin to notice sheens of sunscreen at popular tourist sites, and the question of whether it has an effect on the local corals begins to form.

A Danovaro et al. paper publishes first study linking sunscreen exposure and coral bleaching.

A study finds that oxybenzone is particularly toxic to corals when compared to other sunscreen ingredients. In the study scientists found that when corals were exposed to high doses in a lab setting oxybenzone caused bleaching, DNA damage, abnormal growth, and developmental deformities in baby corals. 

Hawaii bans oxybenzone and octinoxate due to their toxicity to corals. Other tourist destinations and countries start to follow suit, including Aruba, Thailand, and the Florida Keys.

The National Academies publishes an extensive assessment calling for further research into the effects of sunscreen on the environment. They assert that chemicals like oxybenzone and octinoxate can have ill effects on corals, but only in high concentrations often not experienced in the natural world, even when high numbers of sunscreen-clad tourists visit a popular site.