sunscreen sunscreen sunscreen, also known as sunblock or sun cream, is a photoprotective topical product for the skin that helps protect against sunburn and most importantly prevent skin cancer. sunscreens come as lotions, sprays, gels, foams (such as an expanded foam lotion or whipped lotion ), sticks, powders and other topical products. sunscreens are common supplements to clothing, particularly sunglasses, sunhats and special sun protective clothing, and other forms of photoprotection (such as umbrellas). sunscreensunscreen on back under normal and uv lightother namessun screen, sunblock, sunburn cream, sun cream, block out sunscreens are classified into two types: mineral (also referred to as physical) sunscreens (i.e., zinc oxide and titanium dioxide) and chemical (also referred to as petrochemical, as they are typically derived from petroleum) sunscreens. research by the fda on the safety of the main three organic uv filters (oxybenzone, homosalate and octocrylene) found that the three ingredients could be detected on the skin, in blood, in breast milk and in urine samples weeks after no longer being used. medical organizations such as the american cancer society recommend the use of sunscreen because it aids in the prevention of squamous cell carcinomas. the routine use of sunscreens may also reduce the risk of melanoma. however, many sunscreens do not block ultraviolet a (uva) radiation, yet protection from uva is important for the prevention of skin cancer. to provide a better indication of their ability to protect against skin cancer and other diseases associated with uva radiation (such as phytophotodermatitis), the use of broad-spectrum (uva/uvb) sunscreens has been recommended. some sunscreens include an expiration date—a date indicating when they may become less effective. history sama-bajau woman from maiga island, semporna, sabah, malaysia, with traditional sun protection called burak burmese girls wearing thanaka for sun protection and cosmetic purposes. early civilizations used a variety of plant products to help protect the skin from sun damage. for example, ancient greeks used olive oil for this purpose, and ancient egyptians used extracts of rice, jasmine, and lupine plants whose products are still used in skin care today. zinc oxide paste has also been popular for skin protection for thousands of years. among the nomadic sea-going sama-bajau people of the philippines, malaysia, and indonesia, a common type of sun protection is a paste called borak or burak, which was made from water weeds, rice and spices. it is used most commonly by women to protect the face and exposed skin areas from the harsh tropical sun at sea. in myanmar, thanaka, a yellow-white cosmetic paste made of ground bark, is traditionally used for sun protection. the first ultraviolet b filters were produced in 1928. followed by the first sunscreen, invented in australia by chemist h.a. milton blake, in 1932 formulating with the uv filter 'salol' (phenyl salicylate) at a concentration of 10%. its protection was verified by the university of adelaide. in 1936, l'oreal released its first sunscreen product, formulated by french chemist eugène schueller. early adopters of sunscreen were the us military. in 1944, as the hazards of sun overexposure became apparent to soldiers stationed in the pacific tropics at the height of world war ii, benjamin green, an airman and later a pharmacist produced red vet pet (for red veterinary petrolatum) for the us military. sales boomed when coppertone improved and commercialized the substance under the coppertone girl and bain de soleil branding in the early 1950s. in 1946, austrian chemist franz greiter introduced a product, called gletscher crème (glacier cream), subsequently became the basis for the company piz buin, named in honor of the mountain where greiter allegedly received the sunburn. in 1974, greiter adapted earlier calculations from friedrich ellinger and rudolf schulze and introduced the "sun protection factor" (spf), which has become the global standard for measuring uvb protection. it has been estimated that gletscher crème had an spf of 2. water-resistant sunscreens were introduced in 1977, and recent development efforts have focused on overcoming later concerns by making sunscreen protection both longer-lasting and broader-spectrum(protection from both uva & uvb rays), as well as more appealing to use. health effects