Control of the human head louse with disulfiram and benzyl benzoate emulsions. A laboratory study

The effects of disulfiram, benzyl benzoate and DDT, all components of a common preparation (Tenutex) for the control of the head louse, were tested on louse eggs. A significant higher mortality of eggs was evident after treatment with (i) disulfiram, (ii) benzyl benzoate, (iii) these two substances mixed, and (iv) Tenutex. DDT in this concentration had no effect on the survival of the eggs. Long-time exposure to Tenutex and Tenutex without DDT significantly lowered the hatching frequency of eggs. Almost no hatching occurred after exposure for 24 hours. The survival of larvae hatched from eggs treated with Tenutex was lower than for those treated with Tenutex without DDT. DDT seemed to have an effect primarily on the survival of larvae. Newly hatched larvae were more sensitive to the two Tenutex preparations than older larvae.