What is the capacity of pesticide toxicity primarily measured by?

The capacity of pesticide toxicity is primarily measured by its ability to cause injury to humans. This aspect focuses on how harmful a pesticide can be when humans are exposed to it, whether through direct contact, inhalation, or ingestion. Toxicity assessments involve determining the dose at which a pesticide can cause adverse effects, including acute toxicity (immediate effects) and chronic toxicity (long-term effects). Understanding this helps pesticide applicators evaluate risks, implement safety measures, and adhere to regulations regarding safe usage.

While the other options may relate to certain environmental and safety concerns regarding pesticides, they do not directly measure toxicity in the context of its impact on human health. For instance, the potential for polluting groundwater relates to environmental impact rather than direct toxicity, flammability is about fire risk, and the duration of activity in the environment pertains to residual activity rather than toxicity. Focusing on human injury gives a direct correlation to the health and safety implications of pesticide usage.