- 5 - 
4 1 For dust and powder formulations .—A vo id excessive inhalation, 
t Avoid contamination of foodstuffs. 
DDT in Aerosols 
» 
DDT in aerosols will give only partial and temporary relief from 
flea infestations in the house. The immature stages of the inseot 
are not likely to be killed with one application, but daily applica- 
tions for a week may do a fair job. A few seconds' release of the 
fog is sufficient for rooms containing a few thousand cubic feet of 
air space (see directions on containers). This method is not an 
economical one to use, however, and is therefore not recommended for 
the oontrol of fleas. 
DDT in Dusts 
Dusts containing 10 percent of DDT in diluents such as talc or 
pyrophyllite may be used direotly on dogs and other animals, except 
cats, for controlling adult fleas. These dusts are very effeotive 
also in killing fleas in rat burrows, in basements, in houses, on 
bare ground under buildings, and in lawns. DDT powders of this 
strength oan be applied by means of hand dusters in the home or yard. 
If used directly on dogs, about 1 tablespoonful of the 10- percent 
powder to an average-size dog is dusted thoroughly in the hair along 
the back from the head to the tail. It is hazardous to use DDT 
powders on oats , because in their habit of cleaning themselves they 
might ingest enough to make them sick or kill them. In treating rat 
burrows or infested basements about 1 pound of the 10-percent DDT 
dust is used to each 1,000 square feet of floor space. It may be 
applied best by means of a hand duster. 
DDT in Solutions 
DDT oan be dissolved in comparatively few readily available 
solvents which oan be used with reasonable safety. The most con- 
venient solvents are various grades of kerosene and fuel oil. For 
those who wish to make their solutions, 7 ounces of technical DDT oan 
be dissolved in 1 gallon of kerosene to make a 5-percent DDT solution. 
Highly refined greaseless kerosene will not dissolve so much DDT, and 
the fuel oils will dissolve a little more than common kerosene. DDT 
should not be used in gasoline . 
DDT in oil solutions is very effeotive against flea larvae, but 
should not be used on animals because of the danger of burning them. 
A 6-peroent DDT solution applied by means of a small hand sprayer is 
reoommended for treating flea- infested floors, rugs, overstuffed 
furniture, and basements. For use on delicate fabrics one should 
