Figure 8: The UV absorbances of 0.10% retinol formulations before irradiation (dark blue, dashed line) and after 5 MED (red and green)—approx. the amount of UVR in one hour’s worth of mid-summer sun.

The formulation with 4% EHMC (blue) retains 100% of its UV absorbance, indicating little if any loss of retinol. The formulation without EHMC lost 86% of its UV absorbance.