For both cannabis and hemp-derived CBD products, purity and quality come down to the individual farmers and manufacturers, and practices vary widely.
There are both hemp and cannabis farmers working hard to grow clean, organic plants that are safe for human consumption, yet conversely, there are hemp and cannabis farmers who are using questionable practices. Likewise, there are product manufacturers who are taking great care to extract CBD from either cannabis or hemp in ways that are mindful of what residual toxins from the extraction process might make it into their extracts and final products. And there are those who are not so mindful.
According to Martin Lee of Project CBD, CBD oil is actually a co-product or by-product of growing industrial hemp and a way that farmers can make additional money by selling unused hemp biomass:
“This dual-use practice is widespread among large-scale hemp growers in Canada, for example, but it’s technically illegal, entirely unregulated, and the hemp biomass sold via underground channels is often tainted with pesticides and requires toxic solvents to extract the CBD.”
When much of our source material for making hemp-CBD products comes from abroad, this is a scary thought. Touching upon Lee’s mention of extraction methods, this is another area of concern when it comes to cannabis- and hemp-derived CBD. Not all extraction methods are created equally and some of them can be unsafe for consumers. Another argument that is often made against hemp-derived CBD is in the fact that the plant is a bioremediatory. This means that hemp takes in substances from the soil, both good and bad, through its roots. Like other plants, both hemp and cannabis take in nutrients and water from the soil as well as other contaminants from their environment, including bacteria, fungi, pesticides, and heavy metals. These toxins can remain in the plant if there is too much for the plant to digest, a process called bioaccumulation.
The plants hold these toxins in their leaves, stems, stalks, roots, and flowers. When these plants are harvested and processed for consumption, these contaminants can be extremely hazardous to your health, even at low levels. The problem with hemp-based CBD is that the bioaccumulation effect is compounded: It takes a lot of hemp to get a little bit of CBD. This means that, all things being equal, there would be comparatively more toxins in a hemp-derived CBD product than a cannabis one. Without uniform regulations for heavy metal testing, consumers may be consuming products containing cadmium, lead, arsenic, or mercury, all of which pose serious health risks. This is why sourcing clean and responsibly grown organic hemp and cannabis products is so important.