THE LIMITATIONS OF FORMALDEHYDE GAS AS A DISINFECTANT, 
WITH SPECIAL REFERENCE TO CAR SANITATION. 
By Thomas B. McClixtic, 
Passed Assistant Surgeon, U. S. Public Health and Marine-Hospital Service .a 
INTRODUCTION. 
This work was undertaken in order to throw further light upon the 
much discussed question as to the merits of formaldehyde gas as a 
germicidal agent and the best method of obtaining it for disinfecting 
purposes, a problem which has been of much interest to the Service in 
its public health work, particularly in its relation to car sanitation. 
Some preliminar}^ experiments soon showed certain limitations to 
the use of formaldehyde gas as a disinfectant, and on account of the 
practical importance of these limitiations they were taken up and 
studied under definite conditions. 
A special study was made of the production of formaldehyde gas b j 
the action of potassium permanganate on formalin. When these two 
substances are brought together a vigorous reaction takes place 
accompanied by rapid liberation of formaldehyde gas. 
Although this is a comparatively new method of liberating the gas 
it is not clear, from a review of the literature, who was the first to sug- 
gest it. Certainly among the first to describe it was Dr. G. F. John- 
son, of Sioux City, Iowa; this was done in a paper read at the eighth 
semiannual meeting of the Sioux Valiev Medical Association held at 
Sioux City, Iowa, January 21 and 22, 1904. In the spring and sum- 
mer of the same year Henry D. Evans, 6 chemist, and Dr. J. P. Russell, 
bacteriologist, of the Laboratory of Hygiene, Augusta, Me., con- 
ducted experiments with formaldehyde gas liberated by this method; 
a Acknowledgments : To Daniel Base, Ph. D., technical assistant in pharmacology, Hysi- 
enic Laboratory, U. S. Public Health and Marine-Hospital Service, I am indebted for the 
chemical determinations made during warm weather and for assistance in the preparation 
of the corresponding part of the text of this bulletin; and to Madison B. Porch, B. S., assist- 
ant in the division of pharmacology, Hygienic Laboratory, for assistance in making the 
chemical determinations during cold weather. 
6 Evans, Henry D., and J. P. Russell: Formaldehyde disinfection. 13th Ann . Rep. Maine 
State Board of Health. 
(U 
