In vitro percutaneous absorption of cobalt
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To evaluate skin absorption of cobalt powder in an in vitro system. Experiments with volunteers show that cobalt powder can permeate through the skin, but there are no data with regard to the mechanism or the amount of permeation.
Skin permeation was calculated by the Franz diffusion cell method with human skin. A physiological solution was used as receiving phase and the cobalt powder was dispersed in synthetic sweat. The amount of metal passing through the skin was analysed by electro-thermal atomic absorption spectrometry (ETAAS). Parallel polarographic analysis (differential pulse polarography—DPP) allowed evaluation of cobalt present as ions (Co2+) in donor and receiving phases. Measurements of cobalt skin content were also performed.
Evaluation of metal in the receiving phase allowed us to demonstrate the permeation of cobalt through the skin. Steady-state flow of percutaneous cobalt permeation was calculated as 0.0123±0.0054 μg cm−2 h−1, with a lag time of 1.55±0.71 h.
The experiments show that cobalt powder can pass through the skin when applied as a dispersion in synthetic sweat, oxidising metallic cobalt into ions, which permeate the skin. These experiments show for the first time how cobalt can permeate the skin.
KeywordsCobalt Skin Franz diffusion cell Percutaneous absorption In vitro experiments
The authors acknowledge the financial support by the European Community, Contract QLK4-CT-2000-00196.
- American Conference of Governmental Industrial Hygienists (ACGIH) (1995) Threshold limit values (TLVs) for chemical substances and physical agents and biological exposure indices (BEIs). ACGIH, Cincinnati, USAGoogle Scholar
- Carson BL, Ellis HV, McCann JL (1986) Toxicology and biological monitoring of metals in humans. Lewis, Chelsea, pp 75–92Google Scholar
- Flora CJ, Nioboer E (1980) Determination of nickel by differential pulse polarography with dropping mercury electrode. Anal Chem 52:1013–1020Google Scholar
- Franz TJ (1975) On the relevance of in vitro data. J Invest Dermatol 93:633–640Google Scholar
- Kogan VY, Petukhova NE (1986) Cobalt. UNEP, MoscowGoogle Scholar
- Lauwerys R, Lison D (1994) Health risk associated with cobalt exposure. An overview. Sci Total Environ 150:1–6Google Scholar
- Mellor JW (1953) Comprehensive treatise on inorganic and theoretical chemistry, vol XIV. Longmans, Green, pp 513–514Google Scholar
- Organization for Economic Co-operation and Development (OECD) (2000) Draft guidance document for the conduct of skin absorption studies. OECD, ParisGoogle Scholar
- Pascal P, Nouveau (1963)Traité de chimie minerale, vol XVII. Masson, pp 85Google Scholar
- Scansetti G, Botta GC, Spinelli P, Reviglione L, Ponzetti C (1994) Absorption and excretion of cobalt in the hard metal industry. Sci Tot Environ 150:141–144Google Scholar
- Suzuki-Yasumoto M, Inaba J (1976) Absorption and metabolism of radioactive cobalt compounds through normal and wounded skin. Diagn Treat Radionuclides Proc Int Sem 119–136Google Scholar