Irreversibility in chemical exposure signifies what?

Irreversibility in chemical exposure indicates that once a change occurs due to the exposure, it cannot be undone or modified by any intervention. This means that the damage or effect caused by the chemical is permanent and will have lasting consequences on the affected individual or environment. For instance, certain chemicals can cause cellular damage, mutations, or chronic health issues that cannot be repaired, making it crucial to understand the potential for irreversible effects when evaluating chemical hazards.

The other options suggest that a change can be fixed or will eventually resolve, which does not align with the notion of irreversibility. Therefore, understanding that certain exposures can lead to permanent changes reinforces the importance of safety measures and precaution when dealing with potentially harmful substances.