Which hazard statement indicates a severe risk if ingested?

The statement "Toxic if swallowed" indicates a severe risk if ingested because the term "toxic" conveys a high level of danger associated with exposure. Toxic substances are capable of causing significant harm or even death upon ingestion. This reflects a serious concern for health and safety, signaling that immediate action, such as medical attention, may be necessary if accidental ingestion occurs.

In contrast, the other statements suggest varying degrees of risk. "May be harmful if swallowed" and "Harmful if swallowed" imply a lesser degree of risk compared to "toxic," as they do not use the same level of severity in their terminology. "Not hazardous if swallowed" clearly indicates there is no risk, which further underscores why "Toxic if swallowed" is the most alarming and appropriate choice when assessing the severity of health risks related to ingestion.