SKIN PROPERTIES OF TAIWANESE WOMEN 305 (7) E. K. Biosits et al., The refined regression method, J. Cutan. Aging Cosmet. DermatoL, 1, 155-163 (1989). (8) M. M. Rieger and D. E. Deem, Skin moisturizers: Methods for measuring water regain, mechanical properties, and transepidermal moisture loss of stratum corneum,J. Soc. Cosmet. Chem., 25, 239-252 (1974). (9) D.C. Salter, Instrumental methods of assessing skin moisturization, Cosmet. Toiletr., 102, 103-109 (1987). (10) P. L. Dorogi and M. Zielinski, Assessment of skin conditions using profilometry, Cosmet. Toiletr., 104, 39-44 (1989). (11) E. W. Packman and E. H. Gans, Topical moisturizers: Quantification of their effect on superficial fa- cial lines,J. Soc. Cosmet. Chem., 29, 79-90 (1978). (12) G. Nole et al., Global face assessment•A clinical evaluation method, Cosmet. Toiletr., 109, 69-72 (1994).

j. soc Cosmet. Chem., 47, 307-313 (September/October 1996) In vivo photoprotective effect of I-bis(carboxyethyl)germanium sesquioxide L. MONTENEGRO and E P. BONINA, Department of Pharmaceutical Sciences, University of Catania, Vle A. Doria 6, 95125 Catania, Italy, and J. C. DEDEREN, ICI Surfactants, Everslaan 45, Everberg, Belgium. Accepted for publication September 3 O, 1996. Synopsis In this paper in vivo radical scavenger activity of [3-bis(carboxyethyl)germanium sesquioxide (CEG) was in- vestigated. CEG aqueous solutions were topically applied to healthy human volunteers before and after skin exposure to UVB radiation. Skin erythema was monitored by calculating erythema index values from the skin spectral data obtained using a reflectance spectrophotometer. The results of these experiments indi- cated that CEG was not able to inhibit UVB-induced skin erythema both in the pretreatment and in the posttreatment protocol. In order to assess if the lack of CEG photoprotective activity was due to poor CEG in vivo skin permeation, we tested CEG aqueous formulations containing a skin penetration enhancer such as dimethylisosorbide (DMI). CEG aqueous solutions containing DMI were able to reduce UVB-induced skin erythema when applied before skin exposure to UV radiation, but they were ineffective when topically applied after UVB irradiation. INTRODUCTION The use of radical scavengers to prevent UV-induced skin damage has recently been met with considerable interest. Bissett et al. (1) and Trevithick (2) reported that superoxide- scavenging antioxidants, such as tocopherol and tocopheryl acetate, decreased UVB skin damage after topical application in mice. Other authors (3) suggested that topical free radical scavengers, like SOD, could exert photoprotective effects against ultraviolet ra- diation-induced cutaneous damage. [3-Bis(carboxyethyl)germanium sesquioxide (Arlamol GEO ©, CEG) (Figure 1), a com- pound of very low toxicity, has been shown to have antioxidant/radical scavenger prop- erties in in vitro studies (4,5). Presently CEG is used in anti-aging and skin-protective products in Europe and Asia and as a dietary supplement in several Asian and European countries. However, to date in the literature no data have been reported on a CEG pro- tective effect against UV radiation. Therefore, in this study the in vivo radical scavenger activity was assessed by determin- ing the ability of CEG to reduce UVB-induced skin erythema on healthy human volun- teers. CEG aqueous solutions were topically applied before and after skin exposure to UVB radiation, and the subsequent skin erythema was monitored by calculating ery- 307