DID YOU KNOW THAT MARIJUANA IS THE THIRD MOST USED DRUG in the world? More about epidemiology in a moment. A recent study suggests marijuana users may be exposed to unexpected toxins, including cadmium and lead. Today, we explore how lead and cadmium might be in your bud. Marijuana toxins.

I don’t use marijuana; it’s not that I am opposed to its use for folks who are not teens or young adults.

It’s simply not my thing. And I loath the smell of the smoked variety.

Today, I want to explore marijuana contamination, including heavy metals. First, a quote from Jamaican reggae singer, musician, and songwriter Bob Marley:

“When you smoke the herb, it reveals you to yourself.”
― Bob Marley

Marijuana Remains Illegal at the Federal Level

Marijuana remains illegal at the federal level. In this context, no broad regulation of contaminants in cannabis-containing productions exists.

Moreover, the U.S. Environmental Protection Agency and the Food and Drug Administration provide no guidance.

Marijuana Use is Common

As noted, marijuana is the world’s third most commonly used drug. Can you guess the top two?

If you said tobacco and alcohol, that’s a bingo.

And what about the United States? As of August 29, 2023, 38 states and Washington, DC, have legalized the recreational use of marijuana.

According to the 2021 National Survey on Drug Use and Health, among Americans aged 12 or older in 2021, 19 percent (or 52.2 million people) reported using marijuana in the prior year.

How many young students use cannabis? In 2022, an estimated eight percent of 8th, 20 percent of 10th, and 31 percent of 12th graders reported using cannabis/hashish in the past 12 months.

Potential Toxicities of Marijuana

Marijuana use is not without potential perils. For example, approximately three in 10 marijuana users develop a marijuana use disorder. The risk is even higher for those using this drug before age 18.

Second, marijuana influences the brain, including brain parts responsible for the following:

• Memory
• Attention
• Learning
• Decision-making
• Emotion
• Coordination
• Reaction time.

Those in their teens or younger are especially vulnerable to marijuana’s effects.

Third, frequent (or long-term) marijuana use increases the risk of psychosis in some consumers, according to an English study.

Subjects using high-potency cannabis (skunk-type) daily had the earliest onset of mental illness.

One final note: Pregnant and breastfeeding persons should not use marijuana.

Unveiling Unexpected Toxins in Marijuana

A new study from Columbia University (New York City) examines the presence of toxins in marijuana.

The researchers explain that because the cannabis plant is a known scavenger of metals, they hypothesized marijuana users have higher metal biomarker levels than those without use.

Let’s get right to the study results:

Some marijuana users may have elevated levels of lead and cadmium — two heavy metals linked to long-term health issues — in their blood and urine.

The investigators combined data from the National Health and Nutrition Examination Survey (2005–2018) for 7254 participants, classifying the subjects into these categories: 1) no marijuana or tobacco use; 2) exclusive marijuana use; 3) exclusive tobacco use; and 3) users of both.

They measured five metals in blood and 16 in urine using inductively coupled plasma mass spectrometry; researchers adjusted urinary metal levels for urinary creatinine (a measure of kidney function).

Marijuana and Toxins: Study Results in More Detail

Among the 7,200 adults, 358 reported using marijuana within the prior 30 days. These individuals had nearly 1.3 times higher blood lead levels than non-users of tobacco and alcohol.

The marijuana consumers also had 1.22 times higher levels of blood cadmium. Urine samples yielded similar findings.

The Columbia University team already knew that cannabis plants can readily absorb heavy metals from soil. The contaminants travel via the plant stalk into the leaves and flowers.

The new findings show that the heavy metals known to be in cannabis plants can end up in the human body, too.

With a growing number of cannabis users, I hope we see more studies examining cannabis use and contaminants (including metals).

Is There A Safe Metal Level?

Unfortunately, there is no safe lead exposure level. Even low levels can slow children’s brain development.

Lead exposure is associated with behavioral and learning problems.

Chronic exposure to lead can increase the risk of hypertension (high blood pressure), kidney damage, and heart issues for adults.

The World Health Organization considers cadmium to increase cancer risk. Moreover, exposure to low levels (such as tobacco smoke exposure) can cause kidney disease and fragile bones.

Unfortunately, lead and cadmium can stay in the body for years, even after the exposure to the toxins ends.

My Thoughts — Unveiling Unexpected Toxins in Marijuana

The study did not distinguish between various ways participants consumed marijuana, such as joints or edibles. In general, inhaling lead is worse than eating it; the inhalation rate is 100 percent.

Unfortunately, both cadmium and lead typically linger in the body for years.

The good news? Twenty-eight states regulate arsenic, cadmium, lead, and mercury in marijuana products. Manufacturers must ensure concentration levels are below a designated level in these states.

The bad news? Each of the regulating states (where cannabis is legal) sets its contaminant limits. And all bets are off for illegal products.

What Can You Do?

One way to know if a marijuana product has no heavy metal contamination is to purchase the product from a legal dispensary.

Your state health department website may have a list.

Next, ask a dispensary staff member for a certificate of analysis showing your desired product has no heavy metals.

I look forward to writing about the potential benefits of marijuana use.

Two more things:

In the Weeds: Unveiling Medical Marijuana Uses

Are Heavy Metals in Your Dark Chocolate?

The information I provided in this blog is for educational purposes only and does not substitute for professional medical advice.

Please consult a medical professional or healthcare provider for medical advice, diagnoses, or treatment. I am not liable for risks or issues associated with using or acting upon the information in this blog.

Thank you for reading “Marijuana Toxins.”