by Dr. Bill Rawls
Updated 11/11/22

Cannabidiol or CBD oil has exploded in popularity as a health supplement, and for good reason: Scientific research shows CBD — a cannabinoid or chemical component of cannabis plant species like hemp and marijuana — has potential to help with many conditions and ailments, including anxiety, chronic pain, sleep issues, and even seizure disorders and schizophrenia.

It’s crucial, however, that consumers make sure any CBD they purchase has been lab tested for purity and potency. Because of CBD’s evolving legal status from state to state, CBD products are largely unregulated, and it’s an unfortunate reality that substandard or inaccurately labeled products are on the market.

For instance, in a 2022 study in Science of the Total Environment, nearly 60% of CBD products tested didn’t have the correct percentage of CBD on the labels.

Fortunately, by learning more about CBD testing and the types of extracts that are available, you can avoid snake oil products and make sure you’re getting what you’re paying for — along with all the potential health benefits that come with it.

Be Wary of Misleading Labeling of CBD Products

When you purchase an over-the-counter medication such as aspirin, its contents and claims have been vetted by the U.S. Food and Drug Administration (FDA). CBD, however, currently occupies a legal gray area. Regulatory gaps on the federal and state levels have led to inadequate oversight, and some bad actors have taken advantage of the situation.

For example, the Centers for Disease Control and Prevention (CDC) reported at least 52 people in Utah were poisoned after consuming what they thought was CBD oil. When investigators tested the source product, it contained a synthetic cannabinoid, but no CBD.

In the aforementioned 2022 study, researchers tested 121 edible CBD products and discovered the presence of heavy metals, including lead (42%), cadmium (8%), arsenic (28%), and mercury (37%), and hormone-disrupting, industrial chemicals such as phthalates.

colorful gummy bears on white surface

The FDA has sent warnings to businesses that make unsubstantiated health claims in order to market CBD and posted test results of a sampling of products. But until regulated compliance is standardized and legally enforced, consumers are wise to be diligent in vetting CBD products, particularly when it comes to ingredient sourcing and lab-testing results, when choosing the right type of product for their needs.

Why It’s Crucial You Know the Source of Your Hemp

Because the laws are more restrictive for marijuana-derived CBD products, many consumers and manufacturers are opting for CBD products made from hemp. It’s essential, however, to know where the hemp was sourced.

The hemp plant is well-known for its ability to draw heavy metals and other toxins out of soil through its root system in a process called phytoremediation. Hemp plants are so effective at absorbing toxins that they’ve been used to clean soil contaminated by the 1986 Chernobyl nuclear disaster. The downside here is that hemp can also absorb toxins present in the soil where it’s grown.

male hand reaching out to touch hemp plants, in greenhouse

It’s recommended that any hemp used for CBD products is grown in uncontaminated soil that’s free of lead, cadmium, and harmful pesticides, preferably using organic farming practices in a greenhouse versus outdoors. If hemp is sourced from other countries, there are no guarantees these conditions will be met. U.S.-grown hemp received a major boost with the passage of the 2018 Farm Bill, and American hemp production is on the rise. American- and greenhouse-grown, organically farmed hemp is highly recommended as the best source of CBD.

What to Look for in CBD Product Testing

The number one sign of a reputable company in the CBD sector: They’re quick to demonstrate their transparency and ethical practices by readily sharing with consumers third-party lab testing results of their CBD products. Here’s why that’s true.

Third-party independent laboratories have no connection or association with the grower, manufacturer, or brand; thus, their results can be considered neutral, unbiased, and reliable. Labs that are certified by the International Organization for Standardization (ISO) are particularly trustworthy, because it means they meet well-established quality management standards mandated by the worldwide ISO federation.

While individual laboratories and reporting processes vary, here is what CBD products are most commonly tested for, and a quick breakdown of these categories:

  • Cannabinoid profile and potency
  • Terpene content
  • Heavy metals
  • Residual solvents
  • Pesticide residues
  • Microbiological contaminants

icon of hemp leaf in glass testing jar

Cannabinoid Profile and Potency

This is important for hemp CBD products, which are legally required to contain less than 0.3% THC (the psychoactive compound in marijuana). Although there are more than 100 known cannabinoids in hemp, fewer than 20 are detectable in a laboratory analysis. Not all labs are sophisticated enough to measure all of them, but you want a lab that is. Unmeasured cannabinoids can count toward CBD levels and inflate the amount of CBD that’s claimed to be in the bottle.

icon of hemp leaf over molecules

Terpene Content

Terpenes are the chemical compounds that give plants their scents and flavors. Studies indicate terpenes have numerous health benefits, and may increase the therapeutic qualities of CBD medicine.

icon of metal weight

Heavy Metals

Testing for heavy metals such as arsenic, cadmium, mercury, and lead is a must to ensure product safety. These elements exist naturally in soil in trace amounts, and while they are more likely to be present in dangerous quantities in foods such as rice or seafood, the FDA recommends reducing exposure as much as possible.

icon of yellow chemical container

Residual Solvents

Manufacturers use different extraction methods and chemical solvents such as butane, carbon dioxide, or ethanol to extract the cannabinoids from the plant material. Lab testing ensures the final product contains minimal or no solvent residue from the extraction process.

icon of pesticide sprayer pack

Pesticide Residues

Conventionally-farmed hemp can be exposed to various herbicides and insecticides. Pesticide testing ensures there are no harmful chemicals in the final product.

icon of microbes

Microbiological Contaminants

This testing ensures no harmful microbes, molds, bacteria, or yeasts are present. Separate tests should be performed for E. coli, Staphylococcus aureus, and Salmonella (highly pathogenic microbes).

After testing, labs provide manufacturers with a Certificate of Analysis (COA), which is an official report of the test results. Reputable companies provide COAs on their websites for consumers to review, and have representatives available to answer any questions regarding test results.

While COAs differ from lab to lab, knowing what CBD products are typically screened for — and also how available a company is to address any concerns — can help consumers make informed choices.

Know Your Types of CBD Extracts

Once you’ve done your diligence and company research, it’s time for product selection. There are three primary types of CBD extract: isolate, full-spectrum, and broad-spectrum. Here’s what to know about each:

molecule diagram of cbd

CBD Isolate

This is pure CBD from which all other plant compounds have been separated, leaving only the single CBD molecule in the extract. In states where THC is illegal or for patients who want a 100% THC-free product, CBD isolate is a useful formulation — but note that it’s missing all of the other beneficial cannabinoids and terpenes found in hemp.

full color wheel of eight colors

Full-Spectrum CBD

Sometimes called whole-plant CBD, full-spectrum is CBD that has been extracted along with the other plant terpenes and other cannabinoids present in the plant. Many experts, myself included, recommend full-spectrum CBD for maximum health benefits.

Studies indicate the various cannabinoids and terpenes in full-spectrum CBD work synergistically, increasing the therapeutic potential through what’s known as the “entourage effect.” While full-spectrum hemp oil with CBD can contain only 0.3% THC, in states where medical cannabis is sold, full-spectrum products may have various CBD:THC ratios, such as 3:1 or 1:1.

partially filled color wheel, mostly invisible

Broad-Spectrum CBD

It’s similar to full-spectrum, however, in broad-spectrum all THC is removed. This formulation is useful for patients who seek a broad range of plant compounds but live in states where THC is illegal or do not wish to consume THC. However, similar to isolate, it may not be as effective as full-spectrum CBD.

The Bottom Line on CBD Testing

Because regulation is still catching up with legalization, it’s vital you know the basics of CBD testing in order to find products that are safe and worth what they cost. The good news is that ethical brands are transparent about their manufacturing processes, will readily supply the lab testing information you’re looking for, and happily answer any of your questions regarding their products.

Dr. Rawls is a physician who overcame Lyme disease through natural herbal therapy. You can learn more about Lyme disease in Dr. Rawls’ new best selling book, Unlocking Lyme.
You can also learn about Dr. Rawls’ personal journey in overcoming Lyme disease and fibromyalgia in his popular blog post, My Chronic Lyme Journey.

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