Final answer:
The signal word for very low oral LD50 values is 'DANGER-POISON.' Lower LD50 values indicate higher toxicity, requiring this label to warn of significant risk upon exposure.
Step-by-step explanation:
The signal word associated with very low oral LD50 values is DANGER-POISON. LD50, or lethal dose-50%, is a crucial measure used to express the toxicity of substances and represents the dose that is lethal to 50% of the test animal population, usually laboratory rats. A lower LD50 value indicates higher toxicity. Substances with very low LD50 values are considered highly toxic and are labeled with the hazard sign DANGER-POISON to alert users to the high level of risk associated with exposure.
This categorization helps in indicating the level of hazard and the necessity for caution when handling such chemicals. The term oral LD50 refers specifically to the dose of the substance that is lethal when ingested. Understanding the significance of these signal words in the context of LD50 is important for safety and health regulations. In terms of toxicology, chemicals with a low LD50 that are hazardous to one's health would require the utmost care during usage, resulting in the strongest warning label: DANGER-POISON.