we usually find protein,urea ,uric acid and some chemical like potassium,calcium,manesium ect...
urea
The most logical answer would be urine, and it is!
Ammonia
urea
acetone
The amount of substance that exceeds the tubular maximum will be found in the urine.
Uric acid is a by product of protein digestion and can be found in the urine.
Benzodiazepines: up to 6 weeks with high level use Urine sample results are usually reported as positive (substance is found) or negative (no substance is found).
Urine.
blood
THC-Tetrahydrocannabinol The main psychoactive substance found in the Cannabis plant. It is found in the bloodstream, urine, and in hair follicles. It stay's in the body for 30-40 days.
sperm is a substance. Semen is a mixture.