Perhaps the donor drinks a lot of water, perhaps the donor is trying to cheat the test.
A dilute specimen, by definition, is a urine specimen that has a creatinine of less than 20 g/dl but greater than 2 g/dl and a specific gravity of 1.0200 or less. These 2 tests are routinely performed on every urine sample that is tested at the Lab. If the specimen meets the above 2 criteria, it is reported as a "Dilute specimen". When a urine specimen is "dilute" and negative, it is possible that drugs in their system may not have been detected. We recommend that an employer have a section in their drug testing policy stating that another specimen be collected as soon as possible with minimum advance notice, this will help prevent false negative results. However, the employer may also elect to accept the negative results with the notation "dilute" from the lab. The company policy should be consistent in all cases. See sample language for company policy.
Policy Option For Non DOT Programs:
Option 1: If the urine specimen is determined to be negative and diluted, require a second test and advise applicant or employee to refrain from drinking excessive amounts of fluids. Be sure to provide minimum possible advance notice for this second collection. The second test shall become the test of record. For existing employees, a company official may escort the employee to the collection site.
Option 2: A negative dilute result will be accepted for compliance with this policy. (This would be the appropriate action if the company policy does not address dilute specimens.)