Signal words in product labeling are used primarily to explain what?

Signal words in product labeling are designed to communicate important safety information regarding the hazards or toxicity associated with the product. These words serve as a critical alert system for users, indicating the level of danger they may face when handling or using the product.

For instance, signal words such as "Danger," "Warning," or "Caution" clearly indicate the severity of hazards. "Danger" typically suggests a high level of toxicity or the possibility of severe injury or death, while "Caution" may refer to lower levels of risk. This classification helps users make informed decisions about safe use and handling practices, ensuring they take appropriate precautions.

In contrast, other choices focus on different aspects of the product. While the catalog of ingredients is important for understanding what is in the product, it does not directly indicate safety risks. The effectiveness of the product relates to how well it performs its intended function but does not address the potential hazards posed to users. Application techniques might guide the user on how to properly use the product but do not inherently convey safety information linked to toxicity or hazards. Thus, signal words specifically cater to alerting the user about the potential risks associated with the product.