Alternate Light Source Findings of Common Topical Cosmetics and Three Removal Methods.

The participants were a convenience sample, largely staff at one urban hospital, and the sample was not powered to represent all skin tones. Most participants were female, although the authors found no references that sex changes how topical products interact with alternate light. The make-up was applied in localized areas to be easily visible in ambient light, not thinly blended as in daily use, so clinical findings may be less distinct. The study did not record white light observations of the products, so how visible the products were in ordinary light cannot be quantified. It tested only 14 products, and the authors note that cosmetics and topical products are too numerous and change too quickly for all to be catalogued. The study used one alternate light unit, and the authors call for research on whether other light sources and filters perform similarly.

Do not treat an alternate light absorption or fluorescence finding as proof of bruising. Common make-up products produced these findings on healthy skin, and the paper states alternate light is not diagnostic and positive absorption findings are not pathognomic of bruising.