Typically, liver, kidney, lungs, heart, brain, muscle, fat, carcass and other tissues are removed and analyzed, to identify the parent compound and any metabolites formed. All of the samples collected are analyzed in order to quantify the levels found in each sample. Chemical levels found in excretory products and tissue samples are then compared to the total dose administered. Efforts should be made to recover all the dose administered. Even the air passing through the animal cage should be collected and analyzed, and the cages are washed down with a solvent for analysis.
Pharmacokinetic studies provide data useful in many ways.
Clearly, pharmacokinetic data is valuable in gaining a better understanding of how an animal or human reacts to a chemical. For example, pharmacokinetic data are used to select proper dosages for therapeutic drugs. In addition, they can be utilized in assessing the hazards of chemical exposures. Identification of chemical metabolites through pharmacokinetic studies is also important in making interspecies comparisons. If a chemical responds in a similar manner in several different species, then one species may be a good model for others.