Distribution is governed by several factors, including blood flow, tissue affinity, and the presence of protein binding sites. Highly perfused organs like the liver, kidneys, and brain receive toxicants more rapidly. The lipophilicity of a chemical can enhance its distribution to fatty tissues, whereas hydrophilic compounds often remain in the extracellular fluids. The binding of toxicants to plasma proteins can either facilitate or hinder their distribution, impacting their ultimate bioavailability.
