The purpose of this investigation is to study the adulteration of local anesthetics in the marked condoms 266 samples were purchased in 1986. Thin layer chromatography and gas chromatography were applied to analyze these samples. None of them were found adultered with Benzocaine. Carbocaine HCl Cocaine HCl. Lidocaine HCl. Procaine HCl or Tetracaine HCl.