What term describes the ingredients in a pesticide that actively kill or control pests?

The term that describes the ingredients in a pesticide that actively kill or control pests is "active ingredients." These are the primary components of a pesticide formulation that are specifically responsible for the desired biological activity—whether it's killing pests, repelling them, or otherwise managing their populations. Understanding the nature of active ingredients is crucial for anyone involved in pest management, as they determine the effectiveness and mode of action of a pesticide.

In contrast, inactive ingredients serve other purposes, such as enhancing the stability, safety, or application of the pesticide but do not directly affect pest control. Preservatives are used to prolong the shelf-life of products and maintain their efficacy over time, while residual compounds refer to substances that remain in the environment after pesticide application, rather than being part of the formulation that actively engages with pests. By focusing on the term "active ingredients," individuals in pest management can make informed decisions regarding product selection and usage.