What signal word signifies a moderately toxic substance?

The signal word that signifies a moderately toxic substance is "WARNING." This term is specifically used on pesticide labels to indicate that the chemical poses a moderate level of toxicity to humans and animals through various exposure routes, such as ingestion, inhalation, or skin contact.

In the context of pesticide toxicity, different signal words are utilized to categorize the danger level associated with a product. For example, "DANGER" is reserved for highly toxic substances that can cause serious harm or death if the recommended precautions are not followed. Conversely, "CAUTION" indicates substances that are relatively low in toxicity but still require careful handling and awareness due to potential risks. Additionally, "Caution or no signal" would refer to products that are either low in toxicity or do not pose significant risks and may not need a warning signal.

Understanding these categorizations is crucial for safe handling and application of pesticides, ensuring the protection of applicators, bystanders, and the environment.