SciELO - Scientific Electronic Library Online

 
vol.64Speciation of Co(II), Ni(II) and Cu(II) complexes with L-glutamic acid in Dioxan-Water mixturesElucidation of the complex Baylis-Hillman reaction of 3-methoxy-2-nitrobenzaldehyde with methyl vinyl ketone author indexsubject indexarticles search
Home Pagealphabetic serial listing  

South African Journal of Chemistry

On-line version ISSN 1996-840X

Abstract

BUNHU, Tavengwa; KINDNESS, Andrew  and  MARTINCIGH, Bice S.. Determination of titanium dioxide in commercial sunscreens by inductively coupled plasma-optical emission spectrometry. S.Afr.j.chem. (Online) [online]. 2011, vol.64, pp. 139-143. ISSN 1996-840X.

A variety of sunscreen products have been developed to afford the consumer protection against some of the deleterious effects, for example erythema, caused by solar ultraviolet radiation. The requirement that suncare products offer broad-spectrum protection has resulted in the use of inorganic oxides, such as micronized titanium dioxide (TiO2), in their formulation. However, there are now concerns about the photocatalytic effects of the TiO2 in these products and its potential phototoxicity to the skin through the generation of reactive oxygen species such as hydroxyl and superoxide anion radicals. It is important, therefore, that the amounts of TiO2 in suncare products be closely monitored and maintained within stipulated ranges. A simple, fast and reliable analytical method for the determination of TiO2 in commercial sunscreen products by inductively coupled plasma-optical emission spectrometry (ICP-OES) was developed and validated. The limits of detection and quantitation were found to be 0.018 and 0.062mL-1, respectively. The average percentage recovery of TiO2 was 102.32 ± 2.87 % with a RSD of 2.81 %. The method was applied to determine the concentration of TiO2 in 22 commercial suncare samples of which 14 contained TiO2. The amounts of TiO2 measured in these sunscreens ranged from 0.05 to 3.21 %. To our knowledge this is the first study that reports the amounts of TiO2 in sunscreen products available on the South African market.

Keywords : Titanium dioxide; sunscreens; physical blocker; inductively coupled plasma-optical emission spectrometry.

        · text in English     · English ( pdf )

 

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License