Toxicological Chemistry of Oxygen

As noted in a very informative summary by McKersie, although molecular oxygen is required by humans and other oxic organisms for energy metabolism and respiration, it plays an important role in a number of significant diseases and degenerative conditions. Such adverse health conditions are 

FIGURE 6.9 Lewis structure representations of oxygen species involved in oxidative stress processes. Although triplet (ground state) molecular oxygen molecules are sometimes depicted by the simplified Lewis structural formulas shown, a complete description of the electronic behavior of these molecules requires use of molecular orbital theory, which is beyond the scope of this work. 

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