The contact angle (CA: deg) method [1] has been used for the determination of the wettability of solids and semisolid substrates such as cosmetics and formulations for cutaneous applications [2]. As regards biomaterials, this method can evaluate the hydration state of skin [2] and demonstrate its usefulness in the beauty sector field [3].  

On this basis, our work aimed to evaluate the basal moisturizing level of in-vivo skins of a workers group (subjects test) employed in a commercial holding company sited in Treviso (Italy). The skin wettability of each subject test (ST) was evaluated using a portable MobilDrop DSA2 mobile tensiometer (tenskinmeter®)[2] and a single drop of microfiltered water (Ares Solida srls, Treviso, Italia). The water CAs measurements were performed before and after the skin application of a liposome dispersion (Skindecoder®) and a commercial hydration cream (shc). The test was repeated after seven days during which each subject test kept its systemic hydration level administrating two liters of water per day. Our work demonstrated a decrease of water CAs measured after the application of Skindecoder® (ST RU=-58%, ST ROS=-51%, ST GIU=-51.98, ST MATT=-56.80%, ST ROB=-65.54%, ST GRE=-55.16%, ST ILA=-81.28%) and chc (ST RU=-68.77%, ST ROS=-26.30%, ST GIU=-32.23, ST MATT=-45.48%, ST ROB=-41.30%, ST GRE=-48.98%, ST ILA=-45.65%) at t0. That demonstrated the increase of hydration state due to the two formulations' application. The basal water CAs measured after seven days decreased for ST RU (-13.22%), ST ROS (-51.15%), ST GIU (-3.09%), ST MATT (-10.63%), ST ROB (-21.73%), ST GRE (-12.00%), and ILA (-8.02%). 

These data show that the regular administration of 2Lt of water per day causes a decrease in the water CAs of STs with a measurable increase in skin hydration that depends on the biological properties of each worker tested. 

Our pilot study opened with the perspective of considering the moisturizing of the human epidermis as a possible biological parameter to control in a rapid and non-invasive way the employee's health about their water intake during job activities in public and private institutions.