EFFECT OF REPEATED APPLICATIONS OF SUBLETHAL CONCENTRATIONS OF GERMICIDES ON LIVING EMBRYONIC TISSUE FRAGMENTS

¹ From the Department of Bacteriology, University of California, Los Angeles

The results reported show that tissue fragments cultivated in vitro may be successfully employed to demonstrate the presence of a cumulative action in germicidal compounds or preparations.

Iodine and Hexylresorcinol did not exhibit an appreciable cumulative action on proliferating tissue when applied twice daily for 12 days.

Under the same conditions mercuric chloride exhibited a pronounced cumulative action after 72 hours resulting in the death of the tissue fragments.

The organic mercurials Merthiolate and Metaphen produced considerable damage to the fibroblasts but did not exhibit an appreciable cumulative effect on the tissue fragments. The fragments remained vigorous throughout the experimental period.

Silver nitrate produced considerable damage on the fibroblasts and a slow cumulation of silver in the tissue fragments.

The organic silver protein strong also produced considerable damage on the fibroblasts but the tissue fragments remained vigorous throughout the experimental period, indicating that the cumulation of silver was negligible.