202 Microbes and You 



either accidentally or with suicidal intent, egg white is admin- 

 istered as an antidote. The mercury combines with the egg pro- 

 tein, and by inducing vomiting, much of the mercury can be ex- 

 pelled before it works its way into the body, if the antidote is given 

 promptly. 



Bv converting mercury into complex organic compounds, much 

 of the toxicity, corrosiveness, and protein-coagulating properties 

 are reduced. Such compounds as merthiolate, metaphen, mer- 

 curochrome, and phenyl mercuric nitrate are representative of these 

 organic combinations, and they include some of our best skin dis- 

 infectants. Merthiolate in particular enjoys an excellent reputa- 

 tion as a pre-surgical applicant for the skin. Many home medicine 

 chests and first aid kits, which formerly contained iodine, now have 

 tincture of merthiolate as the disinfectant of choice for superficial 

 wounds. Laboratory tests confirm the high killing power of 

 merthiolate. An aqueous solution of mercurochrome has relatively 

 little bactericidal power, but a tincture of this same compound has 

 more value. 



2. Silver Salts are rather effective in killinof bacteria, due to the 

 oligodynamic action of the silver resulting from the reduction of 

 silver ions. Silver nitrate (AgNOy) is a well-known silver com- 

 pound, and it is found to be bactericidal in a concentration of 

 1:1000 and bacteriostatic up to 1:10,000. Argyrol and protargol 

 contain colloidal silver. 



Until Crede introduced silver nitrate as a prophylactic, gonor- 

 rhea of the eyes of young babies was one of the leading causes of 

 blindness in children attending schools for such handicapped 

 persons. 



3. Zinc Salts are weak antiseptics, at best. Not all heavy 

 metals have the same bacteria-killing capacity, and zinc salts are 

 mentioned merely to note why they are used at all. Zinc sulphate 

 is commonly employed as an eye wash because it does exert a 

 soothing action on the delicate eye membranes. The chloride of 

 zinc is a constituent of some dentifrices and mouth washes, but 

 the germicidal claims sometimes attributed to the action of this 

 compound do not stand up under close scrutiny. 



