Figure 7

Assessments of phototoxicity of CC fraction. (A). Dose-response curve and results for chlorpromazine. After simulated sunlight, the lethality of Balb 3T3 cells A31 increases. Scores of PIF and MPE classify chlorpromazine as phototoxic and the OECD TG 432 defines the following reference parameters: IC₅₀ (Irr+) = 0.1 to 2.0 µg/ml, IC₅₀ (Irr−) = 7.0 to 90.0 µg/ml and PIF > 6. (B,C) Representative optical micrograph of the neutral red uptake in samples treated with 0.46 µg/ml chlorpromazine (non-irradiated and irradiated, respectively). (D) Dose-response curve and results for the CC fraction induced-phototoxicity. The presence of simulated sunlight was not able to reduce significantly the cell viability to the maximum concentration of 1 mg/ml allowed by the test. According to the MPE score, the CC fraction can be classified as non-phototoxic (MPE < 0.1). (E,F) Representative optical micrograph of the neutral red uptake after treatment with 1.0 mg/ml CC fraction (not irradiated and irradiated, respectively). Error bar represents a confidence interval of 95% (n = 12, of two independent experiments of n = 6) of a t-student distribution. Cells were irradiated for 50 min in irradiance of 1.7 mW/cm². The viability of the irradiated control is more than 80% relatively to the non-irradiated control, thus exposure to simulated sunlight alone does not cause significant baseline cytotoxicity in the test system.