How does your liver actually filter toxins from blood?

The liver filters blood through several chemical processes rather than acting like a simple physical filter. Blood flows in from two sources: the hepatic artery bringing oxygenated blood and the portal vein bringing nutrient-rich blood directly from the intestines. Liver cells called hepatocytes then chemically transform harmful substances through two main phases. Phase one uses enzymes, particularly the cytochrome P450 family, to break down toxins through oxidation, reduction, or hydrolysis. Phase two attaches molecules like glucuronic acid or sulfate to these broken-down compounds, making them water-soluble. Once water-soluble, the substances can be excreted either into bile, which carries them to the intestines for elimination in stool, or into the bloodstream to be filtered by the kidneys and excreted in urine.