PABA, benzocaine, and other PABA esters in sunscreens and after-sun products

Abstract

Contact/photocontact allergy to PABA and benzocaine are not uncommon. PABA and PABA esters are used in sunscreens and benzocaine may contaminate such sunscreens or may be an intentional constituent in after-sun products. Labelling of ingredients in sunscreens and after-sun products is not required by law in Sweden. The presence of PABA, PABA esters used as sunscreen agents, and benzocaine was therefore investigated by HPLC in 97 sunscreens and 15 after-sun products. PABA was detected in 2 sunscreens while almost 50% of the sunscreens contained 2-ethylhexyl p-dimethyl-aminobenzoate. Benzocaine was not found in any after-sun product but was present in 1 sunscreen containing 4-bis(hydroxypropyl)aminobenzoate. Glyceryl p-aminobenzoate and amyl p-dimethyl-aminobenzoate were labeled on 1 and 3 sunscreens, respectively, but glyceryl p-aminobenzoate was not found in any of them and only traces of amyl p-dimethylaminobenzoate were found in 1 sunscreen.