DISINFECTANTS AND THEIR 

 STANDARDIZATION 



By WATSON LEWIS, D.V.M, Saint Paul, Minnesota 



An antiseptic prevents the growth, of germs, while a 

 disinfectant kills them. It is hard to say just where 

 antiseptic action leaves off and disinfectant begins, 

 for they are so closely allied that the terms are com- 

 monly used synonymously. It is a well known fact 

 that a substance may cause a marked inhibition of 

 bacterial growth and still be of little value as a germ 

 destroyer. For instance, turpentine will retard the 

 growth of spores in solutions of 1 to 75,000, while 

 carbolic acid only retards in a solution stronger than 

 1 to 1,250. This powerful antiseptic action explains 

 the high efficiency of turpentine in flatulent conditions 

 both in human and in veterinary medicine. 



Nothing is used more frequently in veterinary sur- 

 gery than antiseptics and disinfectants, many of which 

 are standardized. However, such is not the case with 

 coal tar and allied disinfectants, for here no standard 

 has been adopted to protect the consumer against 

 fraud. 



These preparations are now offered on the market 

 at prices varying from fifty cents to five dollars a gal- 

 lon. The five-dollar preparation may be actually 

 cheaper than the fifty-cent preparation, because of its 

 germicidal value. Accurate test shows that there are 

 preparations fifteen to seventeen times more efficient 

 than carbolic acid, but they do not sell for fifty cents 

 a gallon. 



