Yellowish or colorless solid; [Merck Index] White or off-white crystalline powder; [Alfa Aesar MSDS] Intravenous LD50 (mouse) = 178 mg/kg; [RTECS] "Causes contact dermatitis." [ChemIDplus] A skin and strong eye irritant; [Alfa Aesar MSDS] See "N-Aminophthalimide."