The development of new insecticidal formulations is important to overcome the burgeoning hurdle of insecticide resistance in field populations of mosquitoes and other pest arthropods. In order to standardize the testing of current and future small molecule chemical agents as insecticides, specific protocols should be shared, broadly endorsed, and certified among public health entomologists to decrease the variability in toxicological endpoints observed between laboratories. As variability in

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... icological data can result due to differences among sub-populations acquired from the field, experimenter, environment, etc., it is paramount to diminish the effect of factors that contribute to variability in scientific protocols, whenever possible. We propose the utilization of a single topical application protocol that will aid in the characterization of both current and future (in development) insecticidal active compounds. This protocol may be utilized to calculate the theoretical dose required to kill a specific percentage of a pest population (e. g. LD 25 , LD 50 , LD 95 ) and to compare the toxicity of insecticides in a given pest population or sub-sample. Moreover, it may allow for the evaluation of insecticide resistance to be quantified compared to a given susceptible strain. The adoption of this protocol by numerous testing laboratories should decrease the variability in data observed between different researchers and increase the translatability of toxicological characterizations within the scientific community. In order to analyze toxicological dose-response data and obtain theoretical dose-response statistics, it is recommended that you choose 5 concentrations of your insecticidal agent that consistently produce between 10-90% mortality at 24 hr. This will allow for the PROBIT model to relaibly and accurately calculate an LD 50 value. This is the most informative value for comparing insecticidal efficacy of different compounds and dose-level for calculating resistance ratios between various strains. These concentrations can be found by making a variety of doses (range-finding doses) and applying them to an initial set of mosquitoes. The low or high mortality produced by these formulations can be updated accordingly to produce toxicologically informative concentrations.