MAR 25, 2015 8:08 AM PDT

Legalizing Marijuana and the New Science of Weed

WRITTEN BY: Judy O'Rourke
More than a year into Colorado's experiment legalizing marijuana, labs testing the plants are able for the first time to take stock of the drug's potency and contaminants -- and openly paint a picture of what's in today's weed.

At the National Meeting & Exposition of the American Chemical Society (ACS), one such lab is presenting trends -- and some surprises -- that its preliminary testing has revealed about the marijuana now on the market.
Marijuana buds are often two to three times as potent as they were 30 years ago.
Three major patterns have emerged over the past few months since Andy LaFrate, PhD, and his lab began testing marijuana samples. Those patterns concern potency, amounts of a substance called CBD, and contaminants in the products.

"As far as potency goes, it's been surprising how strong a lot of the marijuana is," LaFrate says. "We've seen potency values close to 30 percent THC, which is huge." LaFrate is the president and director of research of Charas Scientific, one of eight labs certified by Colorado to do potency testing.

THC is an abbreviation for tetrahydrocannabinol, which is the psychoactive compound in the plant. He explains that three decades ago, THC levels were well below 10 percent. Its content has tripled in some strains because producers have been cross-breeding them over the years to meet user demands for higher potency, he says.

But an unexpected consequence of this breeding has occurred, says LaFrate. Many of the samples his lab has tested have little to no cannabidiol, or CBD. CBD is a lesser known compound in marijuana that is of increasing interest to medical marijuana proponents. Researchers are investigating CBD as a treatment for schizophrenia, Huntington's disease, and Alzheimer's disease. It is also being considered for anxiety and depression. But unlike THC, CBD doesn't get people high -- that's a key trait for many people who are wary of buzz-inducing drugs and for potential medical treatments for children. As for recreational users, the lack of CBD in marijuana means that many of the hundreds of strains they select from could in actuality be very similar chemically, according to LaFrate.

"There's a lot of homogeneity whether you're talking medical or retail level," he says. "One plant might have green leaves and another purple, and the absolute amount of cannabinoids might change, which relates to strength. But the ratio of THC to CBD to other cannabinoids isn't changing a whole lot." That means there might be little difference in how the varieties make you feel, even though some people claim one kind will make you mellow and another will make you alert, LaFrate explains.

As for contamination testing, although Colorado doesn't yet require it, some producers have voluntarily submitted samples to see what's in their products. LaFrate says the results have been surprising. His lab looks for both biological and chemical contaminants, such as pathogenic microbes and solvents.

"It's pretty startling just how dirty a lot of this stuff is," he says. "You'll see a marijuana bud that looks beautiful. And then we run it through a biological assay, and we see that it's covered in fungi."

The lab also finds varying levels of chemical contaminants such as butane, which is used to create marijuana extracts. Contamination isn't necessarily a cause for alarm, but it does signal a need to figure out what levels are safe.

"It's a natural product," LaFrate says. "There's going to be microbial growth on it no matter what you do. So the questions become: What's a safe threshold? And which contaminants do we need to be concerned about?"

In other words, legalizing marijuana has raised a lot of issues that still have to be hammered out. LaFrate, who has been involved with the policy side of Colorado's new marijuana market, as well as the laboratory side, says he expects regulations will continue to evolve as scientists, lawmakers and others learn more about the plant and its products.

[Source: American Chemical Society]
About the Author
  • Judy O'Rourke worked as a newspaper reporter before becoming chief editor of Clinical Lab Products magazine. As a freelance writer today, she is interested in finding the story behind the latest developments in medicine and science, and in learning what lies ahead.
You May Also Like
MAR 15, 2020
Space & Astronomy
MAR 15, 2020
This Exoplanet Rains... Iron!?
Many of us take the Earth and its many ‘normal’ characteristics for granted, but there are so many exoplanet ...
MAR 21, 2020
Chemistry & Physics
MAR 21, 2020
Making underwater solar cells more efficient
New research published in the journal Joule suggests that wide-band gap semiconductors are more effective in underw ...
APR 01, 2020
Chemistry & Physics
APR 01, 2020
Discovery of a new molecule could improve storage of big data
New research from scientists at the University of Limerick's Bernal Institute details the discovery of a molecule th ...
APR 07, 2020
Chemistry & Physics
APR 07, 2020
The anti-bacterial superpowers of silver
Now more than ever we are all thinking about germs. Germs, microbes, bacteria, viruses – it’s a constant min ...
MAY 01, 2020
Chemistry & Physics
MAY 01, 2020
John Conway: the Late Maths Legend and His Game of Life
If maths is the only universal language, then John Horton Conway is among the few who can speak it perfectly. Unfortunat ...
MAY 25, 2020
Plants & Animals
MAY 25, 2020
Ever Wonder How Some Fish Produce Electricity?
When you hear the term ‘electric fish,’ the first thing that probably comes to mind is the infamous electric ...
Loading Comments...