Assessment of surfactant cytotoxicity: comparison with the Draize eye test

Abstract

Synopsis We have compared the in vitro cellular toxicity and the in vivo ocular irritation potency of 16 surfactants (7 non ionics, 3 anionics, 2 amphoterics, 4 cationics) ranking from very weakly irritant to strongly irritant. In vitro, the cellular toxicity was estimated on Chinese hamster lung fibroblasts (V79) using a cell mortality test and a cell growth inhibition test. For each surfactant, a lethal concentration 50% without foetal calf serum (LC.50-0) and with 10% foetal calf serum (LC50-I0), as well as the concentration required to reduce 50% of the growth (CI.50) were determined. In vivo, each surfactant was applied directly to the cornea of six albino rabbits. The maximal ocular irritation score (I0 max) and the ocular irritation score obtained seven days later (I0 J7) were collected. Comparison of in vitro results with those obtained in vivo showed good correlations, particularly when I0 max and the difference (LC.50-10 - LC50-0) were considered (r= 0.845, P<0.001). These results suggest that the use of cell culture tests as pre-screening systems to appreciate eye irritation potency of surfactants could be a reliable alternative method in order to reduce the use of the Draize rabbit eye test. They can provide a better knowledge of the irritative process induced by surfactants (cellular toxicity and protein interaction potency).

Liposome Assay for Evaluating Ocular Toxicity of Surfactants

“…Both coefficients were computed for comparisons with either in vitro method, as both Pearson's 3,4,6 -8,13,18,20 and Spearman's 3,6,8,19 have been reported for correlations between in vitro methods and Draize data. The prediction equations calculated from Draize data at 10% from Kennah et al, 18 Tachon et al, 19 and Matsukawa et al 4 were compared with 95% confidence intervals used for mean Draize scores as a function of percentage calcein leakage (JMP software; SAS, Cary, NC). The predicted Draize scores from the correlations were used to assign each surfactant to one of three categories based on the following scale: mild/moderate (0 -25), irritant (Ͼ25-50), and severe (Ͼ50 -110).…”

“…Draize scores for 10 of the surfactants tested (SDS, Tween 20, Tween 40, Tween 80, Triton X-100, MTAB, CTAB, OTAB, CPC, and BKC) were obtained from three independently published studies. 4,18,19 Kennah et al 18 published 24-hour average Draize scores for multiple concentrations of surfactants, enabling two correlations from their publication. Their scores for concentrations of 10% and 1% (vol%) were used.…”

“…For SDS, those authors reported Draize scores for 30%, 15%, and 3% surfactant concentrations, and their data were fitted to a calibration curve to compute the corresponding Draize scores at 10% and 1%. Tachon et al 19 reported the maximum Draize score after 1 hour or 24 hours at 10% wt/vol surfactant concentrations. Finally, Matsukawa et al 4 reported both the maximum average scores and the 24-hour average scores for 10% solutions; the latter was used for consistency.…”

“…The confidence intervals of the three separate correlations are later compared to determine whether there are statistical differences between the predictions based on the three correlations. In Figure 1, we plotted the Draize scores from different studies versus the percentage dye leakage after 10 minutes at fixed surfactant 18 and Tachon et al 19 and assumed to behave similarly to cetyl pyridinium chloride which was tested here. concentrations.…”

A cell suspension agar diffusion test using Neutral Red release to assess the relative irritancy potential of cosmetic ingredients and formulations

“…Numerous cell-based tests are under development [1][2][3][4][5][6][7][8][9][10] as prescreens for, or as alternatives to, in vivo tests for skin and eye imtancy, although few have been validated to the satisfaction of regulatory authorities. The aim of the present work was not to attempt extensive validation, but to develop a practical cytotoxicity assay which could be used in-house by manufacturers to screen cosmetic and toiletry ingredients and products for relative irritancy, and to indicate where reformulation was necessary.…”