Adulteration is the tampering of a urine specimen with the intention of altering the test results. The use of adulterants can cause false negative results in drug tests by either interfering with the screening test and/ or destroying the drugs present in the urine. Dilution may also be employed in an attempt to produce false negative drug test results.

One of the best ways to test for adulteration or dilution is to determine certain urinary characteristics such as creatinine, pH, and specific gravity and to detect the presence of glutaraldehyde, nitrite and oxidants /pyridinium chlorochromate (PCC) in urine.

Creatinine is a waste product of creatine; an amino-acid contained in muscle tissue and found in urine.

Almost anyone can obtain products that are marketed, designed, and sold to alter urine drug use screening tests. These products are often referred to as masking products and generally fall into one of four categories:

1. dilution substances that are added to a urine specimen at the time it is collected or are ingested before an individual submits a urine Specimen.
2. cleansing substances that detoxify or cleanse the urine and are ingested prior to the time that an individual submits a urine Specimen
3. adulterants that are used to destroy or alter the chemical make-up of drugs and are added to a urine specimen at the time that it is provided for testing; and 4) synthetic or drug-free urine that is substituted in place of an individual's specimen and provided for testing.

If you suspect that a urine sample may have been altered or "masked", you should consider using a urine adulteration test to check the sample.

There is an array of products designed to dilute, cleanse, or substitute urine specimens submitted to testers by drug users to adulterate urine samples. For more information on products which mask the presence of illegal drugs when a urine drug test is administered, see Detox - Pass A Drug Test.