For the agrochemicals industry, the analytical quality control of pesticide products ensures that a consistent and effective product reaches the farm. More specifically, the detection, characterization, and quantitation of the active ingredient(s) as well as all other components in the formulation, including impurities and degradation products, is necessary to support product development, quality control, and product registration. The addition of a mass detector in conjunction with UV detection can increase the specificity and selectivity of methods used during analytical testing to provide additional information about a sample during a single analysis. The Waters ACQUITY QDa Detector is a novel mass detector that can be integrated into existing liquid chromatography configurations in order to complement the results obtained by UV detectors and increase the detection selectivity. The enhanced selectivity is ideal for the detection and initial identification of low-concentration components present in samples. When MS data is combined with the UV response, it allows the analyst to determine a wider range of analytes in one analytical run with an increased level of confidence. In this application note, optical and mass detection were combined to provide a thorough profile of a commercially available pesticide formulation concentrate.