An appraisal of the efficacy and substantivity of the new high-potency sunscreens.

Several recently introduced sunscreens were evaluated using test procedures proposed by the Food and Drug Administration. The newer sunscreens proved to be highly protective, possessing Sun Protection Factors (SPF) of 15 or greater. Improvement in efficacy was achieved by the incorporation of a combination of active ingredients at larger concentrations, and by superior vehicle design. A procedure is also described for the laboratory assessment of wash-off resistance, which provides data comparable to those obtained from swimming tests. Two of the tested sunscreens resisted wash-off after 40 minutes of swimming.