DISINFECTANTS. ANTISEPTICS 177 



example, operates by coagulating albumin, by its acid reaction, 

 by precipitation and by the action of its chlorine. 



Disinfectants and the Infected Objects. — The results obtained 

 by experiments in bacteriological laboratories cannot be applied 

 to disinfection in practice without further consideration (compare 

 iodoform!). Between the destruction of bacteria in artificial 

 cultures and the disinfection of a living body, a wound, a stable 

 or a manure pit there frequently exist very considerable differ- 

 ences. Therefore, in practice it is well to consider the inter-action 

 between the disinfectant and the object to be disinfected; both, 

 the disinfectant as well as the object, may under certain circum- 

 stances suffer changes in consequence of opposing influences 

 which will entirely defeat the purposes of the disinfection. 



For the living body, the first point to be determined is whether 

 the disinfectant is poisonous or non-poisonous. Strictly speaking, 

 there is no disinfectant which is strongly antiseptic and at the 

 same time absolutely non-toxic for the animal body. It is rather 

 the rule that the toxicity of a disinfectant increases with the 

 strength of its antiseptic power, as is observed especially in con- 

 nection with corrosive subUmate. But if the term poisonous is 

 used in the ordinary sense, and is to be understood to mean harm- 

 ful results from small quantities of the disinfectant, or from weak 

 dilutions used in the usual way for practical disinfection, then it 

 can be said that there are disinfectants which are not poisonous. 

 As examples, boric acid, salicylic acid, aluminum acetate and 

 creoHn may be mentioned. In regard to the former denials of 

 the non-toxicity of the latter drug, the investigations of von 

 Behring and experiences in practice agree that creolin may be 

 employed as a disinfectant without any danger of poisoning. As 

 poisonous antiseptics may be mentioned carbolic acid, creosote, 

 the free cresols, corrosive sublimate, formaldehyde, chlorine, 

 bromine and iodine. Corrosive sublimate is the most poisonous; 

 it is forty times as poisonous as carbolic acid. According to von 

 Behring, the toxicity of a disinfectant for the animal body may be 

 calculated from the action of the drug upon anthrax bacilU sus- 

 pended in blood-serum; most disinfectants are five to seven times 



12 



