[Inconsistency in sun protection factor (SPF) index in Mexico. The case of sunscreens for oily skin].

BACKGROUND

In Mexico, information regardiing sunscreen protection is not widely accessible from sources other than manufacturers.

OBJECTIVE

To assess the Sun Protection Factor (SPF) of 12, over the counter sunscreens for oily or acne-prone skin available in the Mexican market.

SETTING

Dermatology Department. Autonomous University of San Luis Potosí, Mexico.

SUBJECTS AND

METHODS

Twenty healthy volunteers ofskin type III and IV were tested. Sunscreen SPFs were measured using solar simulated radiation according to FDA final monograph.

RESULTS

SPFs ranged between 7.8 and 26.9. Overall SPFs determined by solar simulator showed values between 22% to 74% less than the one advertised in their labels.

CONCLUSIONS

We warn about the potenital risk of SPF overestimation as many of'the sunscreens tested did not comply with their offered protection. A proper regulation is needed because sunscreens are considered cosmetic products and do not require clinical tests to verify their efficacy before marketing.