The sensitization potential of D & C Yellow No. 11 in guinea pigs

The certified drug and cosmetic dye substance known as D & C Yellow No. 11 [2‐(2‐quinolyl)‐1,3 indandione] was tested for its dermal sensitization potential in guinea pigs. An induction regimen consisting of a single footpad injection of Complete Freund's Adjuvant diluted with antigen, and an intradermal injection of antigen, produced delayed‐type hypersensitivity reactions. A high sensitization frequency was observed with 50 μg D & C Yellow No. 11 and the positive control 2,4‐dinitrochlorobenzene (DNCB). The reaction severities of both DNCB and 50 μg D & C Yellow No. 11 were comparable, A dose‐response profile was obtained with D & C Yellow No. 11 employing several concentrations (50, 250 and 500 μg/ml). Histologic examination of selected skin sites demonstrated a celluar inflammatory response which was consistent with delayed‐type hypersensitivity.