UPSC 2017 CDS II GK Paper

The foul smell of urine of a healthy man having healthy food, when spilled on floor, is mainly due to the bacterial decomposition of urea into ammonia. Urea is one of the waste products found in urine. It is a byproduct of the breakdown of protein and can be broken down further into ammonia in certain situations. Therefore, many conditions that result in concentrated urine can cause urine that smells like ammonia.