Relevance of Sun Protection Factor claim
Review of a study with 60 different commercial sunscreen products from European market
This work attempts to compare the labeled SPF (Sun Protection Factor) afforded by 60 different sunscreen products from the European market in comparison with the in vivo SPF measured using international standard based on data published in a safety report. Using a statistical approach, it was demonstrated that in some cases, a significant difference appears between the both SPF values (i.e. labeled and measured) which could lead to be a shortcoming for consumer health and any further correlation with other SPF method.
It’s around the 60’s that for the first time the concept of sunstroke control as a scale allowing longer sun exposure before sunburning was introduced throug, the so called and now well-known Sun Protection Factor (SPFd. it was the only existing iniee proposed and became a worldwide standard for classification of the UV protection efficiency of the sunscreen products unless limited to a single biological reaction (sunstroke) and caused by a small part of UV (ultraviolet, mostly in UVB range. At that time the protection levels were very low, formulas quite basics and focused mainly on UVB part.tThis in vivo SPF assessment is carried out by measuring the Minimal Erythemal Dose (MED) which consists of comparing the UV radiation dose required with and without sunscreen product till the appearance of a skin redness due to UV induced erythema (called sunstroke or sunburn) as a biological endpoint on human volunteers. Clearly, the SPF is only a relative value for product classification and none case representing real life condition and efficiency.
For several years, this in vivo SPF method was not clearly defined with a continuous mo ...