“There’s a stereotype, a hippy kind of mentality, that leads people to assume that growers are using natural cultivation methods and growing organically,” says Andy LaFrate, founder of Charas Scientific, one of eight Colorado labs certified to test cannabis. “That’s not necessarily the case at all.” LaFrate presented his results this week at a meeting of the American Chemical Society (ACS) in Denver.
“It’s pretty startling just how dirty a lot of this stuff is,” LaFrate says. His team commonly found fungi and bacteria in the marijuana products they tested. But for now it’s unclear just how much marijuana growers need to clean up their product. “Like ourselves, this plant is living with bacteria that are essential to its survival. In terms of microbial contamination, it’s kind of hard to say what’s harmful and what’s not,” he adds. “So the questions become: What’s a safe threshold, and which contaminants do we need to be concerned about?”
Medical and recreational marijuana use is increasingly legal—but do consumers know what they’re smoking?
Those thinking that stronger pot is always better pot might think again. Breeding for more powerful marijuana has led to the virtual absence of cannabidol (CBD), a compound being investigated for treatments to a range of ills, from anxiety and depression to schizophrenia, Huntington’s disease and Alzheimer’s. Much of the commercially available marijuana LaFrate’s lab tested packs very little of this particular cannabinoid. “A lot of the time it’s below the detection level of our equipment, or it’s there at a very low concentration that we just categorize as a trace amount,” he says. Consumers specifically seeking medical benefits from cannabis-derived oils or other products may have a tough time determining how much, if any, CBD they contain, because Colorado doesn’t currently require testing.
At the top of that list would be chemical contaminants in products such as concentrates, like the hard, amber-colored Shatter, which contains more than 90 percent THC, LaFrate suggests. Concentrates and edibles (think brownies) make up perhaps half of the current Colorado market. Their makers sometimes suggest that their chosen products are healthier than standard weed because they don’t involve frequent smoking. But some manufacturers employ potentially harmful compounds like butane to strip the plant of most everything but THC. Tests also show that marijuana plants can draw in heavy metals from the soil in which they are grown, and concentrating THC can increase the amounts of heavy metals, pesticides or other substances that end up in a product. That means regulations for their production still need to be hammered out, LaFrate says.
In Colorado, which made marijuana legal in November 2012, the latest results show that the pot lining store shelves is much more potent than the weed of 30 years ago. But the boost in power comes at a cost—modern marijuana mostly lacks the components touted as beneficial by medical marijuana advocates, and it is often contaminated with fungi, pesticides and heavy metals.
Data on the potency or strength of cannabis is limited, but the available evidence suggests there is a wide range in levels of THC (the main psychoactive ingredient). While there has been an increase in the average THC level over the past two decades, the rise has not been dramatic. Increases in THC levels are primarily related to selective breeding and more advanced cultivation techniques.
experiencing chronic coughing, shortness of breath, wheezing or psychotic symptoms
You and your child
Only use cannabis purchased from a trusted source
Younger age equals more risk. The younger a person is when they start using a drug regularly, the more likely they are to experience harms or develop problematic substance use later in life.
Some parents wonder when, where and how to start a conversation about cannabis. They ask themselves or others, “What age is the right age to start talking about drugs?” or “Should I ask the questions or should I wait until my child asks me something?”