Which signal word is associated with very low oral LD50 values?

The signal word associated with very low oral LD50 values is "DANGER-POISON." This classification indicates that a substance is extremely toxic and poses a significant risk to human health, particularly through ingestion.

The term "LD50" refers to the median lethal dose of a substance, which is the amount that would kill 50% of a test population. A low LD50 value signifies high toxicity, meaning that only a small amount of the substance can be lethal. Hence, products that carry the "DANGER-POISON" label are subject to strict regulations and are typically accompanied by specific safety precautions to prevent accidental ingestion.

In contrast, the other signal words like "WARNING," "CAUTION," and "NOTICE" indicate varying levels of toxicity and safety concerns. "WARNING" suggests a moderate level of hazard, while "CAUTION" suggests lower toxicity and the need for careful handling. "NOTICE" is not a standardized signal word for toxicity levels and is often used for general information or advisories rather than specific handling precautions. This hierarchy of signal words helps users understand the risks associated with different chemicals and take appropriate safety measures.