A New Method of Controlling the Head Louse

Abstract

The following insecticides have been found much superior to all others formerly used. (1) 25% technical lauryl thiocyanate in white oil. (2) 50% lethane 384 special in similar oil. (3) derris cream. Lauryl thiocyanate (dodecyl thiocyanate; lauryl rhodanate) is made only by du Pont de Nemours, Wilmington, Del. It is marketed as "lorol rhodanate." The tech. grade contains 60% lauryl thiocyanate and 40% of certain homologues which would be dangerous to man if considerable amts. were present. This danger can be avoided by specifying that the thiocyanate was manufactured from lauryl alcohol which began to distil at or above 236[degree] C. (atmos. press.) and of which 95% distilled below 319[degree] C. The white oil is a high-boiling paraffin (I.B.P. 325[degree] C) with very low aromatic content sold by the Shell Co. as P 31. It is believed that any refined oil of this type would be suitable. Lethane special is cheap, making the cost under 1/5 penny per capita. Derris cream is a derris root powder in a soft soap base. All 3 preps. are harmless, inexpensive and comfortable as well as not very noticeable when applied.