Skin absorption of metals derived from hydrogenated stainless particles in human skin: Results from the TITANS project

Workers involved in the decommissioning and removal of radioactive material from nuclear power plants can come into contact with tritiated dust from stainless steel. This study aimed to investigate metal penetration and permeation after skin contamination with these particles. Static diffusion Franz cells were used with intact, damaged, or broken human skin. Stainless steel particles 316 L were applied to the donor phases, and the receiving solutions were collected at regular intervals for 24 h to determine the amount of metals that penetrated the skin. The effectiveness of the decontamination procedure was investigated after 30 min using water and soap. The metal content in the skin was evaluated after 24 h of exposure. Metals detected were Ni, Cr, Co, Mn, Cu, Mo. For Ni, Mn, and Cu, we found a significant increase in metal permeation in all treated cells compared with the blank (p < 0.02). For Co and Cr, permeation through the skin was significant only in the decontaminated and broken cells (p < 0.05). Decontaminated skin presented higher metal permeation for Ni, Co and Cu compared to intact skin (p < 0.05) while broken skin presented, as expected, the higher permeation profile (p < 0.05) for all metals. The metal that was more represented inside the skin was Cr, with more than 15 μg/cm² for intact skin. Ni inside the skin reached the 10.2 ± 8.5 μg/cm² for intact skin. Overall, the levels of metals in the receiving solution were very low in the case of intact and damaged skin contact, and the metal levels significantly increased only in the case of broken and decontaminated skin. More relevant appears Skin content with sensitizing metals (Ni, Cr, and Co) that can induce allergic sensitization or cause allergic contact dermatitis in subjects already sensitized.