18 



CIRCULAR 9 7 7, U. S. DEPARTMENT OF AGRICULTURE 



REPELLENTS 



The standard mosquito repellents adopted by the Armed Forces 

 during World War II were dimethyl phthalate, 2-ethyl-l,3-hexanediol, 

 Indalone, and 6-2-2 and 1-1-1 mixtures of these three materials. 

 They were covered in a joint Army and Navy specification and 

 amendments (No. 18). A military specification (No. 21) issued in 

 July 1952 covered two revised Orlando mixtures (M-2020 and 

 M-2043), one containing 40 percent of dimethyl phthalate and 30 

 percent each of 2-ethyl-l ,3-hexanediol and dimethyl carhate and the 

 other, 30 percent of propyl A^A^-diethylsuccinamate in place of 

 dimethyl carbate. 



The first repellent developed for the treatment of clothing for 

 protection against ehiggers and adopted by the Army contained 45 

 percent each of benzyl benzoate and dibutyl phthalate and 10 per- 

 cent of an emulsifier (No. 19). Later a clothing treatment was 

 developed at the Orlando laboratory for protection against several 

 kinds of insects. This is known as formula M-1960 and contains 30 

 percent each of A r -butylacetanilide, 2-butyl-2-ethyl-l,3-propanediol, 

 and benzyl benzoate plus 10 percent of an emulsifier (No. 20). 



These and other repellent materials are discussed on pages 74-80. 

 Their approximate specific gravities and melting and boiling points 

 are shown in table 2. 



Table 2. — Specific gravity and melting and boiling 'points of various 



repellents 



Repellent 



Specific gravity 



Melting 

 point 



Boiling 

 point 



Benzyl benzoate 



A T -Butylacetanilide 



.Y-Butyl-4-cyclohexene-l,2-di- 



carboximide 



2-Butyl-2-ethyl-l , 3-propanedioL 



Dibutyl phthalate 



Dimethyl carbate 



Dimethvl phthalate 



2-Ethyl-l,3-hexanediol . 



Hendecenoic acid (undecylenic) _ _. 



Hexyl mandelate 



Indalone 



A'-Propylacetanilide _ . 



Propyl A 7 ", A-diethylsuccinamate^ _ - 



1. 11 

 . 99 



1.09 (28°/28°) 



2 18 

 2 22 



1. 05 



1.16-1.17 (35°/4°) 



1. 19 



. 94 



. 91 (24°/4°) 



1. 02 (28728°) 



1. 06 



40-42 

 7 ~70~ 



°C. 

 324 



277-281 



119-121 

 "340 



24 i 



282 



244 



3 295 



110-115 

 222-225 



1. 01 (15715°) 



1 When no temperature is given, it is understood to be 20°/4° C. 



2 Setting point. 



Decomposes. 



MILITARY-ISSUE ITEMS 



Insecticides and repellents for use in controlling insects are supplied 

 to the Armed Forces in the forms listed in table 3. The Federal and 

 military specification numbers and Federal stock numbers are shown. 

 All items are being converted to Federal stock numbers, and where 

 this has not been accomplished no stock number is given. Similar 

 preparations can also be obtained from commercial sources. The 

 equipment for use in applying the insecticides is listed in table 4. 



