Evaluating the Role of Protective Creams on the Cutaneous Penetration of Ni Nanoparticles

Probing the effectiveness of barrier creams against human skin penetration of nickel powder

“…As can be seen from our results (Figure 1, Table 2), despite the treatment with the formulations, the Ni content reached the RF was higher compared to the controls (not pretreated samples), but no statistically significant differences between the groups were found. Additionally, these results are also in line with our previous study, where Ni penetration was higher for samples pretreated with the creams than for samples not pretreated [23]. From our data, the higher permeation of Ni observed by the application of formulation A may be due to the presence of two transdermal enhancers such as steareth-2 and steareth-21 (emulsifiers), which are able to facilitate the permeation pathway [49].…”

“…Moreover, formulation B is a repairing and protective cream for the epidermal barrier, containing a balanced mixture of fundamental lipids of the epidermis such as ceramide 3, cholesterol, and fatty acids able to restore the skin barrier function [58,59] and palmitamide MEA with soothing activity on irritation and itching [60]. These obtained results concerning the effectiveness of such two products to reduce cutaneous Ni penetration are consistent with our previous study [23]. Further, for samples pretreated with the formulations, the total absorbed amounts (Q abs ) of Ni were statistically different, while the highest total skin absorption of Ni was obtained for not pretreated samples (Table 4), which was expected based on the absence of treatment with the formulations.…”

“…Hagvall et al [18] demonstrated that Ni ions penetrated through the cutaneous barrier, mainly in the stratum corneum and to some extent in the upper parts of the epidermis, while in our tests, Ni ions were more retained in the dermis layer than in the epidermis layers for samples pretreated with creams. The higher distribution of Ni ions in the dermis compared to the epidermis was also observed in our previous work [23]. It is well reported that the percutaneous passage of metals through the injured skin is more pronounced as a consequence of the less efficient cutaneous barrier function, due to histological and skin microenvironmental changes.…”

“…In vitro permeation and distribution in skin layers after 24 h exposure Skin absorption studies were performed in static diffusion cells according to the OECD guidelines [45]. The protocol for testing the skin permeation of Ni after exposure to Ni powder was derived from our previous works [22,23]. The skin pieces were mounted between the donor and receptor chambers of Franz-type static diffusion cells, with the stratum corneum facing the donor chamber.…”

“…Similarly, it was demonstrated that NiNPs dissolved in artificial sweat could produce ions that may penetrate through the skin, directly causing an immune response [12]. Additionally, in our previous paper, it was demonstrated that two commercially available creams (i) one to prevent the dermal absorption of Ni (Nik‐L‐Block™ containing a chelating agent) and (ii) the other as a moisturizing cream (Ceramol 311 basic cream without a chelating agent) decreased Ni accumulation in the skin compared to the untreated samples after exposure to NiNPs [23]. This positive effect can be attributed to the composition of such formulations, which plays an imperative role in dermal uptake of Ni [23].…”