A neat toxicokinetic study may involve several different strategies and depends on the scientific question to be answered. Controlled acute and repeated toxicokinetic animal studies are useful to spot a chemical's biological persistence, tissue, and whole-body half-life, and its potential to bioaccumulate. Toxicokinetic profiles can change with increasing exposure duration or dose. Real-world environmental exposures generally occur as low-level mixtures, like from the air, water, food, or tobacco products. Mixture effects may differ from individual chemical toxicokinetic profiles due to chemical interactions, synergistic, or competitive processes. For other reasons, it's equally important to characterize the toxicokinetics of individual chemicals constituents found in mixtures as information on behavior or fate of the individual chemical can help explain environmental, human, and wildlife biomonitoring studies.