New Study Shows Hair Bleach Degrades Cannabinoids, Can Alter Drug Test Results

As long as cannabis remains federally illegal and bosses remain universally square, the likelihood that you’ll be asked to take a drug test at some point in time remains relatively high.

Of course, not all drug tests are created equal. Different bodily substances can narc you out after different lengths of time. For example, cannabinoids can stick around in your bloodstream for a few days and in your urine for a few weeks, but remain detectable in your hair for up to several months, which has made drug tests reliant on analysis of the latter particularly worrisome, for job seekers and rebellious teens with protective parents alike.

But according to a new study, titled “Influence of cosmetic hair treatments on cannabinoids in hair: bleaching, perming and permanent coloring” and published in the research journal Forensic Science International, confounding the dreaded “hair test” could be as simple as going platinum.

Blonde, And Far From Dumb

Researchers found that bleaching hair with hydrogen peroxide caused “strong chemical degradation on cannabinoids,” particularly THC — and the higher the original cannabinoid concentration, the greater the decrease post-bleach. This means that heavy smokers looking to squeak by without setting off alarm bells could stand to gain the most by going blonde.

And in samples “incubated” with 30 percent hydrogen peroxide, a 93 percent decrease in THC, 78 percent decrease in CBN and 89 percent decrease in CBD were all observed — a shocking reduction for those strands.

But the results also show that bleaching isn’t the only treatment that can impact drug test results. The study also found “any type of cosmetic hair treatment has an effect on cannabinoid concentrations in hair.” Both perming and permanent hair coloring (when done over multiple applications) also reduced a hair sample’s cannabinoid content, albeit less than straight-up bleach jobs did. Single application hair coloring, however, turned out to have little to no impact on any sample’s cannabinoid concentration.

In order to conduct their experiment, researchers obtained 30 THC-positive, untreated hair samples, divided each one in half, treated one of the two halves and then compared their cannabinoid content, identifying concentrations of THC, CBN, CBD and THC-COOH before and after cosmetic alternations were performed. THC-COOH (a metabolite of THC that the body creates after consuming THC) was found to be least impacted by hair treatments, with its levels remaining relatively “stable” compared to other cannabinoids observed and measured. Variations in cannabinoid reduction from sample to sample appeared within the experiment, which researchers chalked up to differences in hair porosity and thickness between them.

Ostensibly, this data was collected to help those who conduct drug tests understand how someone’s self-expression could impact their record of pot abstinence, or lack thereof, but it seems it could also be useful for those of us who’d rather not incur the negative consequences of a positive drug test.

Is honesty the best policy? Sure it is, Mom. But even if protections for workers who use medical marijuana are on the rise and a select few politicians are fighting to liberate parolees from the piss test requirement, you can never been too careful.

It’s probably prudent to have a few tricks up your sleeve if there’s even a remote possibility of a drug screening in your future… and it certainly can’t hurt to try out a flashy new hairstyle in the process.

TELL US, have you ever been drug tested?