APPENDIX 
2,2-Bis (P-CHLOROPHENYL) -1,1,1-TRICHLOROETHANE, KNOWN AS DDT 
A recently introduced insecticidal material, now known to the 
trade and users as technical DDT, consists lar gely of 2,2-bis- 
(p-chlorophenyl) -1,1,1- trichloroethane, which has the formula 
(C.H;Cl) ,CH ‘CCl, and contains as the principal impurity an isomer 
thereof. The pure compound is a colorless, crystalline solid which 
melts at 108° C., but the commercial product is a white powder, 
sometimes rather lumpy and sticky, which melts at a considerably 
lower temperature. DDT was first prepared in 1874 by a German 
chemist, but its insecticidal properties were not known until dis- 
covered by Swiss investigators about 1940. Research conducted at 
the Orlando, Fla., laboratory of the Bureau of Entomology and Plant 
(Quarantine led to the recommendations of DDT to military authorities 
for the control of the body louse and other important pests of man, 
and during 1943 and 1944 it was used effectively in various parts of 
the world. During the crop seasons of 1943 and 1944 it was widely 
tested against a large number of pests of agricultural crops, with 
encouraging results in the case of many insects. Experimental work 
has not progressed to a point where its recommendation for use on 
food crops is warranted. Except for limited quantities for experi- 
mental purposes, the entire production of DDT is at present devoted 
to the needs of the armed forces. 
Caution.—DDT is poisonous and should be handled accordingly. 
It has not been definitely established whether or not DDT residue 
on edible vegetable and fruit products constitutes a health 
hazard, and until this is determined DDT will have to be con- 
sidered in the same category as other poisons. 
SABADILLA 
The term “sabadilla” is applied to insecticides prepared from the 
ground seed of a group of tropical lilacecus plants known as saba- 
dilla or Indian caustic barley. These plants belong to the genus 
Schoenocaulon, and 20 species have been reported, 3 of which occur in 
the United States. The seeds of S. officinale Schlecht and Champ., 
imported chiefly from Venezuela, have been used recently in prepar- 
ing insecticides. The active principle of the seeds is a complex 
mixture of alkaloids called veratrine (composed of cevadine, vera- 
tridine, sabadilline, sabadine, and cevine), found’ mostly in the 
endosperm and embryo. 
Preparations from sabadilla seed have long been known to be toxic 
to certain pests of man and animals, and have been widely used in 
veterinary medicine. Recently impr ovements have been made in the 
method of processing the seed, and during the crop season of 1944 
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