The mass number is critical in toxicology for several reasons:
Isotope Identification: Different isotopes of an element can have varying toxicological properties. For example, the isotopes of lead, such as lead-204, lead-206, lead-207, and lead-208, have different mass numbers and can be used to trace and identify sources of lead contamination. Radioactivity and Stability: Isotopes with higher mass numbers may be unstable and radioactive. Understanding the mass number helps toxicologists evaluate the potential radiation hazards associated with specific substances. Behavior and Interaction: The mass number can affect how a substance interacts biologically. For instance, mercury isotopes with different mass numbers may exhibit different rates of absorption, distribution, and elimination within biological systems.
