Residual activity of benzyl benzoate against Dermatophagoides pteronyssinus (Acari: Pyroglyphidae)

The residual effect of a commercial spray containing 2.0% benzyl benzoate against Dermatophagoides pteronyssinus was evaluated in the laboratory. Filter papers treated with benzyl benzoate were dried for 2 hours and placed in Petri dishes. Adult mites were then added and mortality was assessed following 24 hour contact and at succeeding 4 weeks intervals up to week 28 post-treatment using the same treated filter papers. There was 100% mortality at 24 hours post-treatment, declining progressively to 71% by week 28. Probit analysis estimated a median lethal time (LT50) of 59 weeks.