The Evaluation of a Group of Germicides by the Tissue Culture Technique

Abstract

An improved method is proposed for the evaluation of the efficiency of germicides intended for clinical administration. The compounds are tested for their toxicity to living embryonic tissue as well as for their ability to kill bacteria. A number known as the toxicity index is determined which is defined as the ratio of the highest dilution of disinfectant showing no growth of embryonic tissue in 10 min. to the highest dilution required to kill the test organism in the same period of time. The halogen and phenolic compounds (iodine, azochloramid, hexylresorcinol, etc.), appear to be superior to any of those tested by this technique. They are also comparatively free from any bacteriostatic action. Of the newer compounds azochloramid, hexylresorcinol and metaphen rate the highest. Metaphen shows a very pronounced bacteriostatic effect. Merthiolate and mercurochrome cannot be relied upon to kill Staph. aureus by the above method although they rated considerably better against Eberthella typhosa.