Which formulation type is classified as having a low percentage of active ingredient and is not water-soluble?

The formulation type that is classified as having a low percentage of active ingredient and is not water-soluble is dust. Dust formulations typically contain a relatively low concentration of active ingredients, which allows them to be used in a broader range of environments, including dry areas where water solubility isn't necessary. Dust can be effective in targeting pests or invasive plants by adhering to surfaces where they may reside.

While aerosols are indeed a type of formulation that contains active ingredients, they often have a higher concentration of these substances and are designed to be dispensed in a fine mist or spray, which requires some level of water or propellant for application. Granules are solid particles that do contain active ingredients, but they are often used for slow-release applications and can be water-soluble under certain conditions. Pastes, gels, and other injectable baits may also contain a higher percentage of active ingredients and can be designed for specific applications, making them more varied in their moisture content and characteristics.