Yes, urine can be stored in the fridge before lab testing. In fact, urine is always supposed to be stored in cooler temperatures for testing. This prevents the growth of bacteria in the urine.
No just urine testing.
They do Hair testing.
for drug testing?
Law enforcement agencies and court systems are major users of EtG urine testing.
lipids
Urine, when stored in an air tight container, free from contamination and help under constant specified temperature can be used for drug testing over a lengthy time period. Frozen urine can be kept indefinitely for testing.
By testing urine samples for glucose, proteins and others
Hair and urine testing
based upon urine....levels of human chorionic gonadotropin (hCG) are present in the urine (more than 25 mIU)
urine
DNA drug testing doesn't exist.