Colorado Pot Study: Contaminants and Potency High, Medical Effect Low

Get ready for the next big marijuana controversy.

Charas Scientific, one of eight labs licensed by Colorado to test cannabis for potency, among other things, has conducted a new pot study based on the reported analysis of 600 buds from legal growers and sellers in the state.

This afternoon, Charas Scientific's Andy LaFrate is scheduled to present his findings at the American Chemical Society's National Meeting & Exposition in Denver, which got underway yesterday and runs through March 26; we've included the complete program for the event below.

In advance of the presentation, LaFrate and ACS have released an overview of the study's findings, as encapsulated in a video also shared here.

According to the clip, marijuana in Colorado is often triple the potency of marijuana from decades past.

However, the study calls into question the medical efficacy of that cannabis and also raises concerns about the level of contaminants found on many samples.

An ACS release quotes LaFrate as saying, "As far as potency goes, it's been surprising how strong a lot of the marijuana is. We've seen potency values close to 30 percent THC, which is huge."

He estimates that this amount of THC is approximately three times higher than was common during the 1980s.

The increase has largely been achieved by cross-breeding — but the focus on boosting THC has come at a price, the study maintains.

Here's an excerpt from the release:

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.

Then there's the question of contaminants. LaFrate is said to have been surprised how many samples were covered in fungi or contained chemicals such as butane — even ones that appeared to be clean.

Here's the video released in advance of the study, followed by the ACS program.

249th ACS National Meeting & Exposition: Denver

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