Some substances are more toxic than others. The toxicity of a substance is described by the types of effects it causes and its potency. 1  Types of Effects: Different chemicals cause different effects.
I think I remember reading that injured means bruises and lascerations, seriously injured meant hospital but not life threatening, critically injured meant hospital ICU time and fatally injured meant injuries leading to dying sometime later.
Serious injury means an injury or illness that: (1) Is life-threatening, (2) Results in permanent impairment of a body function or permanent damage to a body structure, or. (3) Necessitates medical or surgical intervention to preclude permanent impairment of a body function or permanent damage to a body structure.