At the end of 120 days what do the red blood cells do?

At the end of their typical lifespan of about 120 days, red blood cells (RBCs) are recognized by the body as aging and are typically removed from circulation by macrophages in the spleen and liver. These macrophages break down the cells, recycling components such as iron and amino acids for use in new blood cells. The heme portion of hemoglobin is converted into bilirubin, which is processed by the liver and eventually excreted. This process helps maintain healthy blood cell levels and overall homeostasis in the body.