Padimate O

Padimate O is an organic compound that is an ingredient in some sunscreens. It is a derivative of PABA, an ester formed by the condensation of 2-ethylhexanol and dimethylaminobenzoic acid. It is a yellowish oily liquid that is insoluble in water. It absorbs ultraviolet rays, thereby preventing direct DNA-damage by UV-B. Unfortunately the excited padimate O molecule reacts bimolecularly with DNA and produces indirect DNA-damages, that are similar to those done by ionizing radiation. Therfore padimate o is presumably photocarcinogenic.