Watering down the “Pot of Gold”: What you should KNOW about “Diluted” Urine Drug Tests
Have you ever received a drug test result that says “Negative Dilute”? If you have, I am sure you were confused about what it meant. Companies immediately face questions like: does the person tested have drugs in their system or not, how does your company policy handle this situation, and should they be tested again.
What is considered “dilution” in urine drug testing?
Dilution is the process of reducing the concentration of drug or drug metabolites in the sample. This is accomplished by adding fluid to the sample or by drinking large amounts of fluid to dilute the specimen, called "internal dilution." If the amount of the natural substance creatinine in the urine is abnormally low, internal dilution may be the cause. Drug testing laboratories all routinely test samples to detect dilution.
A dilute specimen, by definition, is a urine specimen that has a creatinine of between 2mg/dL and 20 mg/dl and a specific gravity of 1.003 or less. These 2 tests are routinely performed on every urine sample that is tested at the lab. If the specimen meets the above two 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.
There are 2 circumstances that may cause a dilute specimen. The first would be caused by an individual diluting the urine with water, or other liquid, by actually pouring it into the specimen at the time of collection.
The second method of obtaining a dilute specimen is by consuming too many liquids, especially liquids that contain diuretics, prior to collection (i.e. coffee, soda, medications). This may be inadvertent or may be on purpose on the part of the donor.
What “Dilution” is Not
Dilution should not be confused with “adulteration”. This is when chemical adulterants are directly added to a urine specimen. Many products intended for oral consumption and claiming to help "rid the body of toxins" are sold over the internet. Although these "body cleansing" products may claim to "rid the body of toxins" (a fancy way to say they help beat drug tests), they appear to be effective only because of the large amounts of water the user is instructed to consume along with the teas or powders.
Positive vs. Negative Diluted Specimen
When the lab reports a specimen as dilute, there are certain levels of creatinine and specific gravity that determine that the specimen may be dilute. In other words, the donor consumed a larger quantity of water before providing the urine specimen.
This may be normal as many folks drink a lot of water for health reasons or because of a fear of not being able to urinate at the time of the drug test specimen collection. In contrast, this may be abnormal as perhaps the donor is drinking an excessive quantity of water in an attempt to cheat on the drug test. Thus lies the “gray” area concerning specimens that are reported as dilute.
If the report from your Medical Review Officer (MRO) is “Positive Dilute”, the results is Positive and the company should follow policy for the Positive result. The indication that the specimen was dilute may be interesting, but it is not relevant to the handling of the positive test result.
For “Negative Dilute” results, the first question to ask yourself is whether or not the testing program is a regulated program – Federal employees or DOT drug testing. So what do you do when the Medical Review Officer (MRO) interpreting the drug screen tells you the test is negative, but also dilute?
CleanFleet Can Develop And Review Your Drug And Alcohol Policy
Do you have a company drug and alcohol policy yet? If so, when was the last time you reviewed your policy? CleanFleet can help you develop and review your company’s drug and alcohol policies. Call us today to arrange a consultation with our expert staff at 503-479-6082.