1 



United States Departraent of the Interior! 

 ?ish and liildlife Service | 



'Chicago 54, 111. 



vJildlife Leaflet 288 



MAR 2 7 1947 



!Tay 194S 



]?^CTS iSCUT ^TU 



Prepared in the Division of 'Jildlife Research 



i4lITU is the code designcticn for the chemical alphanapthjrlthiourea. This 

 substance i.ab discovered to be -.. useful Nor-ay rat poison by Dr. Curt p. Richte..-, 

 Johns Hepkins Hospital, Baltimore, lid., xjhile he was vjorking under a grant of 

 funds frojT. the ConLmittee on Kedical Research, of the Office of Scientific 

 Research and Developr.ient, daring World 'Jar II. r^lthoujiti the _joison yas tested 

 early in 1942, little information could be released because of security regula- 

 tions enforced b;;/ the i\rmy. 



x-il^U is a light gx^ay pcvjder, ^luite insoluble in x^ater in most organic sol- 

 vents. It is stable to ordinary heat but vdll melt at about 130 degrees 

 Centigrade. It has no odor, but its taste varies with individuals — many people 

 claim that it is entirely tasteless, v^'hils others find it intens.ljr bitter. 

 There is no known antidote for this poison, and treatment is limited to the use 

 of emetics to remove the toxic agent and carthortics to eliminate it. 



In Norvjay rats, ..-J^irir causes death by changing the permeability cf the blood 

 vessels in the thoracic area, and the animal dies from drovming in its o;:n body 

 fluids, which accumulate in the pleural cavity around the lunas. 



It is much more toxic to NorvJay rats than to the black, Alsxc-ndidne, or 

 frugivorus forms. Even young Norways are miore resistant to it than are adults. 

 ^ small sublethal dose "/ill cause the development of a tolerance to future quan- 

 tities. This tolerance is very marked for several days but is lost after about 

 2 weeks. Rats that have survived this poison v;ill refuse for several weeks to 

 eat baits containing it. 



This poison is' dangerous to dogs as well as to rats,' and must be used' cau- 

 tiously when pets are roairdn;: freely in the areas where treated baits are to be 

 yzposed. It is not highly toxic to monicoys, and presumably that would hold true 

 of man. Diet has a great dei.l to do vJith the susceptibility of an anLmal to the 

 pcison--carnivores, as a class, seem, to be more susceptible than are herbivorous 

 SDocies. 



In spite of its variable characteristics, .uTHJ has been shown to be a use- 

 ful now poison, P':,rtiGularly in the control uf rats, 

 suggested to make its us^.j effective, among 



Several methods hsive been 

 ;hich rjTo the following: 



