DISINFECTANTS 83 



heat has many advantages (e.g., in foods). However, 

 there are cases in which heat cannot be used, as in the 

 sterilization of certain foods, or of catgut, and in chemo- 

 therapy. 



An example of the use of disinfectants in foods and of 

 the subsequent removal by an antidote is the experimental 

 sterilization of milk for cheese making by hydrogen per- 

 oxide which is later destroyed by catalase. This method 

 has been used by Curran, Evans and Leviton (1940) in 

 the study of bacteriology of cheese ripening. Another 

 example is the use of SOo in the fermentation industries. 

 The antidote in this case is atmospheric oxygen which 

 very slowly oxidizes the SO. to sulfuric acid which at 

 these great dilutions is harmless. 



In chemotherapy the entire body may act as an anti- 

 dote. Concerning the role of the body, however, a dis- 

 tinction should be made between two very ditferent modes 

 of action, namely, a chemical combination between the 

 disinfectant and some components of the bodj^, and a 

 mere dilution caused by partial elimination of the poi- 

 son. Only in the first case can we really speak of the 

 body reacting as an antidote. 



The difference between these two modes of action is 

 well illustrated by the experiments of Gegenbauer which 

 will be discussed a few pages below. Staphylococci 

 treated with HgCL could be made to multiply again 

 by repeated washing with water if the exposure had 

 not been longer than one hour. After long exposures, 

 washing did not result in recovery, but an antidote pro- 

 ducing an insoluble compound was capable of making the 

 bacteria multiply again. 



Washing or diluting cannot repair injury. Such op- 

 erations can only remove conditions which prevent the 

 functioning of the uninjured cell mechanisms; they re- 

 move, so to speak, the ''monkey Avrench" from the en- 

 gine. This is illustrated by the fact that most bacteria, 



