What signal word must be on the label for pesticides classified as "highly toxic"?

The label for pesticides classified as "highly toxic" must include the signal word "DANGER!" This term is specifically designated to indicate that the pesticide poses a significant risk of severe injury or death through various exposure routes, such as skin contact, inhalation, or ingestion. The use of "DANGER!" serves as a crucial warning to users about the potential hazards associated with handling and applying these chemicals, emphasizing the need for strict adherence to safety precautions.

In contrast, the other terms—"WARNING!" and "CAUTION!"—denote lower levels of toxicity. "WARNING!" is used for moderately toxic substances, while "CAUTION!" is for those that are slightly toxic or present a lesser risk. "POISON!" could also appear on the label for highly toxic substances, but it is not the standardized signal word required by regulations, which specifically calls for "DANGER!" for high toxicity to ensure immediate recognition of the risks involved. The clear communication of these signal words on pesticide labels is vital for the safety of applicators and the public.