Adulteration is defined as the action of making something poorer in quality by the addition of another substance. Adulteration within drug testing is an attempt to change a urine sample supplied for the purpose of a drug test. Dilution, substitution, or interference are three ways adultering urine drug tests occur.
As part of the testing processes, check the adulteration panel before reading the drug test results. If the sample has been tampered with and the adulteration panel will indicate a positive result. If this occurs you will need to perform the test again.