title: In vitro dermal penetration of nickel nanoparticles.
abstract: Nickel nanoparticles (NiNPs) represent a new type of occupational exposure because, due to the small size/high surface, they can release more Ni ions compared to bulk material. It has been reported a case of a worker who developed sensitization while handling nickel nanopowder without precautions. Therefore there is the need to assess whether the skin absorption of NiNPs is higher compared to bulk nickel. Two independent in vitro experiments were performed using Franz diffusion cells. Eight cells for each experiment were fitted using intact and needle-abraded human skin. The donor phase was a suspension of NiNPs with mean size of 77.7 ± 24.1 nm in synthetic sweat. Ni permeated both types of skin, reaching higher levels up to two orders of magnitude in the damaged skin compared to intact skin (5.2 ± 2.0 vs 0.032 ± 0.010 μg cm(-2), p = 0.006) at 24 h. Total Ni amount into the skin was 29.2 ± 11.2 μg cm(-2) in damaged skin and 9.67 ± 2.70 μg cm(-2) in intact skin (mean and SD, p = 0.006). Skin abrasions lead to doubling the Ni amount in the epidermis and to an increase of ten times in the dermis. This study demonstrated that NiNPs applied on skin surface cause an increase of nickel content into the skin and a significant permeation flux through the skin, higher when a damaged skin protocol was used. Preventive measures are needed when NiNPs are produced and used due to their higher potential to enter in our body compared to bulk nickel.
authors.affiliation: Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127, Trieste, Italy; Department of Medical Sciences, University of Trieste, Via della Pietà 1, 34129, Trieste, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Crosera
authors.affiliation: Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127, Trieste, Italy.
authors.forename: Gianpiero
authors.initials: G
authors.lastname: Adami
authors.affiliation: Department of Medical Sciences, University of Trieste, Via della Pietà 1, 34129, Trieste, Italy.
authors.forename: Marcella
authors.initials: M
authors.lastname: Mauro
authors.affiliation: Department of Medical Sciences, University of Trieste, Via della Pietà 1, 34129, Trieste, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Bovenzi
authors.affiliation: Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, 34127, Trieste, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Baracchini
authors.affiliation: Department of Medical Sciences, University of Trieste, Via della Pietà 1, 34129, Trieste, Italy. Electronic address: larese@units.it.
authors.forename: Francesca
authors.initials: F
authors.lastname: Larese Filon
mesh_terms: D004817:Epidermis / Q000378:metabolism*; D006801:Humans; D053768:Metal Nanoparticles; D009532:Nickel / Q000378:metabolism*; D012869:Skin Absorption
chemical_list: D009532:Nickel
keywords: Damaged skin; In vitro; Nanoparticles; Nickel; Skin penetration