4 
Formula 3 
Dimethyl phthalate - 3 part® 
Indalone 1 part 
Dimethyl Carbate — 1 part 
Mixtures containing two repellents are also fairly effective, 
but these do not repel so wide a range of insects or for so long 
periods as do the triple mixtures. Examples of such mixtures are? 
Formula 4 
Dimethyl phthalate - 2 parts 
Rutgers 612 --—— 1 part 
Formula 5 
Dimethyl phthalate 
Dimethyl Carbate 
2 parts 
1 part 
Some of the repellents that are now offered for sal© under pro¬ 
prietary or trade names contain only a small percentage of the active 
ingredient and a large percentage of alcohol or some other diluent. 
Although such materials have physioal properties that make them more 
acceptable cosmetically, the period of protection is much reduced by 
the addition of the diluent. For maxi m um protection the chemicals 
should not be diluted with inert materials. 
r 
Effeot of Application to the Skin 
These chemicals and their mixtures have been tested by toxi¬ 
cologists and have been found safe for use as skin applications• 
They are toxic if taken internally. Other chemicals have shown 
marked repellent qualities, but they cannot be recommended because 
of their irritating properties. Occasionally there are■people who are 
allergic to certain of the materials that have passed toxicological 
tests. It is possible that a few persons may show slight rash or other 
minor skin reactions to some of the repellents. Any of the ©ffeotive 
and toxioologically safe repellents may cause some " smarting* when 
applied to the mucous membranes and to areas where the skin is especially 
tender, such as the eyelids or groin region or where there are skin 
abrasions• Care should be taken not to apply any of the approved 
materials too liberally on the forehead or eyelids^ as they pause a 
rather severe but temporary stinging if they get^Tnto the "eyes. 
there will be a period after application when the treated skin will 
feel quite warm, especially if the skin is moist with sweat. Ordinarily, 
the sensation lasts for only a few minutes and causes no injury. 
t 
