By measuring TBARS levels, one has an indirect estimate of any UVA and/or UV-filter-induced ROS generated in the systems under study. Fig. 3 and Fig. 4 document the TBARS levels obtained from the different skin samples before and after UVA exposure and in the presence or absence of sunscreens A and B, respectively. TBARS generated from the sunscreens spread onto glass plates are also reported for comparison. In general, one can observe that TBARS are higher in skin samples with sunscreens than without, due to the contribution of TBARS deriving from the sunscreen alone.