Passive transport significantly influences the toxicokinetics of a substance, which includes absorption, distribution, metabolism, and excretion (ADME). For instance:
Absorption: Many toxins enter the body through passive diffusion, particularly across the skin, lungs, and gastrointestinal tract. The rate of absorption is influenced by factors such as the concentration gradient, surface area, and lipid solubility of the toxin.
Distribution: Once absorbed, toxins are distributed throughout the body. Lipophilic toxins may easily cross cell membranes and accumulate in fatty tissues, whereas hydrophilic toxins may remain in the aqueous compartments.
Elimination: Passive transport also plays a role in the excretion of toxins. For example, non-polar toxins may be reabsorbed passively in the renal tubules, making elimination more challenging.
