Evaluation of insecticide aerosol sprays as positive controls for bioefficacy against Aedes aegypti, Musca domestica and Blattella germanica

Abstract

 Quality control of test results is one of the components of quality assurance in laboratories, ensuring that the test results are accurate and reliable. The objective of this study was to evaluate the efficacy of three formulations of insecticide aerosol sprays (labeled A, B, and C), which were selected as a positive control. Formulation A contained cypermethrin 0.20% w/w and imiprothrin 0.15% w/w, formulation B contained cypermethrin 0.15% w/w, imiprothrin 0.10% w/w and transfluthrin 0.10% w/w, and formulation C contained cypermethrin 0.20% w/w, imiprothrin 0.15% w/w, transfluthrin 0.10% w/w and d-tetramethrin 0.10% w/w. The bioefficacy of three formulations were conducted against laboratory strains of Aedes aegypti and Musca domestica using the glass chamber method, and Blattella germanica using the surface contact method. The results showed that all three formulations passed the requirement of bioefficacy tests, with no significant differences in mortality in all insect species. It was concluded that high efficacy was observed in all three evaluated formulations. However, since formulation A contained only two active ingredients, it was more convenient to prepare than formulations B and C. The efficacy of formulation A was then evaluated in ten generations of the three-insect species. The results showed that the mean mortality rates of Ae. aegypti, M. domestica and B. germanica were 100%, 98.50% (SD=2.14) and 100%, respectively. Therefore, formulation A was appropriate for use as a positive control in the bioefficacy test of aerosol insecticide products to evaluate and confirm the results obtained from the laboratory tests. Quality assurance enhances customer’s confidence in the test reports, which will be used to apply for registration with the Thailand Food and Drug Administration (FDA).