kidneys
The kidneys filter the blood to produce urine
the kidney in a human body usually purifys the water you drink which turns into urine
Your bladder has a urine witch cleans out your blood your urine is inside your bladder. A balloon shaped organ in the excretory system.
When your urine is fresh it's actually sterile.
The kidneys make urine. The liver cleans your blood.
If I understand the question if the blood has drugs so will the urine. If you are trying to switch samples that will just get you into more problems.
Menstruation does not expell any blood, contrary to the uninformed belief.
The urea and water that make up urine are removed from the blood in the kidney. This is then passed on to the bladder which will be excreted as urine.
Blood carries nutrients and hormones to every part of your body. Your kidneys' job is to clean the blood, so some hormones are absorbed into the byproduct, urine.
You don't.
To clean the blood and the urine i think also giving nutrients to the body