title: Quantum yield for the photo-degradation of vitamin D3.
abstract: Ultraviolet radiation can photodegrade vitamin D3to suprasterol I, superasterol II and 5,6-transvitamin D3. The probability of the photodegradation of vitamin D3, after the absorption of one photon, is called the quantum yield. We estimated the quantum yield ϕ for all the degeneration reactions together on the basis of the results reported by Webb et al. (1989) for a degradation experiment on pure, tritiated vitamin D3in methanol in sunlight. We find ϕ = (0.42 ± 0.1). This value of the quantum yield can be used to estimate the kinetics contribution from vitamin D3degradation in exposure experiments and model calculations.
authors.affiliation: RIVM, Bilthoven, The Netherlands. Arjan.van.Dijk@RIVM.nl.
authors.forename: Arjan
authors.initials: A
authors.lastname: van Dijk
mesh_terms: D002762:Cholecalciferol / Q000737:chemistry* / Q000528:radiation effects*; D006801:Humans; D007700:Kinetics; D000432:Methanol / Q000737:chemistry; D011789:Quantum Theory; D013472:Sunlight
chemical_list: D002762:Cholecalciferol; D000432:Methanol