Below what daily urine volume can metabolic wastes no longer be removed effectively?

1. Urine volume varies with hydration, but a floor exists below which wastes accumulate. 2. The kidney must clear 100 to 1200 milliosmoles of solutes each day. 3. Those solutes include creatinine, urea and uric acid, all of which need water to carry them. 4. The minimum urine volume that keeps normal function is about 0.47 liters per day. 5. Below that floor metabolic wastes are not removed effectively and organ function is impaired. 6. About 1.5 liters is the daily average, roughly three times the floor, so it is not the limit. 7. Figures below 0.47 liters would already be in the range where waste clearance fails. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 26 "Fluid, Electrolyte, and Acid-Base Balance", section Regulation of Water Output_