The removal of harmful and unwanted toxic waste products of metabolism from the body is known as excretion 

The process by which the water content and the ion concentration is regulated and kept constant in the cells is known as osmoregulation. 

Kidneys perform both excretion and osmoregulation. 

The major waste products are Respiratory wastes, Nitrogenous wastes , Bile pigments 

The Liver and Kidneys are the major "filters" of the blood system, removing toxic wastes and debris.  

The main excretory organ in man are the kidneys. They excrete urine 

The kidneys especially aid in ridding the body of excess "acids" while rebalancing critical pH. If these "filters" are damaged or continuously unclean,  blood will remain laden with debris and heavy metals that could travel to  brain and cause a stroke, become part of the cholesterol plaque hardening  arteries and veins,

 Bile pigments are formed by the breaking down of haemoglobin present in the red blood cells.Worn out red blood cells are destroyed in the liver