Some people try to cheat drug tests. Not most people. Then again, most people don’t need to! But many who are worried about it work very hard to game the system.negative-dilute-drug-test

Nearly 10% of all full-time workers in the U.S. are illicit drug users. Yet only 3.8% of pre-employment urine drug tests are positive. Why?

Several reasons.

For one, not all companies drug test. You can’t test positive if you are not tested at all.

And people cheat. We’ve caught quite a few. They present urine that is too hot or too cold. Or it’s diluted.

Temperature is checked by the collector, but dilution is determined at the lab. Lab results typically come back as one of the following:

  • Negative
  • Positive
  • Negative-dilute
  • Positive-dilute

Negative is what it seems. Positive too. But what is “dilute”? Without getting into the chemistry of it, it means that the donor was exceptionally hydrated at the time of the test, and the urine — and everything it contains — was diluted.

If it’s positive-dilute, there was still a sufficient amount of drug in the urine to produce a positive result, so it’s still a positive.

If it’s negative-dilute, however, that’s often a different story. A common way to pass a drug test is to consume mass quantities of water so that urine runs clear. This can often be enough to pass a drug test, even if there are drugs in a donor’s system.

How do we know this? Experience.

Many employers require a retest of donors with negative-dilute results, and some come back positive on round two. The others? Some people just drink a lot of water.

Does dilution work? Only if you let it.

The U.S. Department of Transportation allows a regulated employer to accept a negative-dilute specimen as negative, and many companies (DOT-regulated or not) choose to accept them. As a result, many substance abusers get hired.

But many of them get caught later during random or post-accident tests. Those positive rates are much higher. Interestingly, those who fail those tests — at some point— passed a pre-employment test.

So what are your choices?

  • You can turn a blind eye, as many companies do, and take your chances with cheaters. (Not the best choice)
  • You can require retesting of all negative-dilute donors. Make sure your policy addresses this and you treat everyone the same. (Recommended)
  • You can incorporate another form of testing that makes cheating harder, such as hair or saliva testing. (Recommended)

Do you need to be an expert in all of this? Nope. That’s why we’re here.

Call InOut Labs today.