The effect of synthetic pyrethroid insecticides on post-treatment emergence of Anobium punctatum
IRG/WP 92-1568
R W Berry
Data is presented from trials in which wood specimens, treated with a range of remedial insecticidal formulations, were aged in a roof void for 5 years and then tested for emergence of adult Anobium punctatum. The technique used followed that described in IRG/WP/2175. The results from formulations containing synthetic pyrethroids are compared with those from formulations containing the chlorinated hydrocarbon insecticides lindane and dieldrin, which have given satisfactory effectiveness in commercial use in the UK for several decades. None of the formulations containing either synthetic pyrethroids or chlorinated hydrocarbons and based on organic solvent allowed any emergence of adult beetles. All of the emulsion-based formulations, with the exception of one based on 1% dieldrin, allowed some emergence. This varied between 4% and 8% of the larval population of the specimens compared with 57% for untreated control. The significance of the levels of emergence observed in treated specimens is discussed in relation to efficacy in practice and it is concluded that further work is necessary to calibrate the results from test method in relation to efficacy.