Heavy Metals Testing for Cannabis: What You Need To Know
Heavy metals are among the most common, and most dangerous, toxins detected in cannabis. While the presence of these contaminants is a worldwide issue in our food and water, cannabis is no exception to this global phenomenon. These metals accumulate in the body, which can pose a health risk over time not dissimilar to mercury accumulation from eating too much tuna and other seafood. To that end, cannabis companies should (and in some cases, are legally obligated to) screen for the presence of heavy metals in their products.
How does heavy metal contamination occur in cannabis?
The cannabis plant (both marijuana and industrial hemp) is well known for its ability to remediate soil. As a bioaccumulator and a remediator, cannabis plants have the unique ability to remove contaminants like heavy metals from the soil, leaving behind a cleaner soil that can be used for any number of purposes. While this is great for the growing medium it leaves behind, it’s not so great for the cannabis plant itself, which may contain higher levels of heavy metals and other contaminants as a result.
It’s not just the growing medium that’s an issue: Cannabis plants can become contaminated from anything that makes its way into the process. The soil, nutrient medium, and water can be sources of heavy metal contamination for cannabis, for example. To help screen for and catch issues with heavy metals before they accumulate, some cultivators regularly test cannabis plants as they are growing, in addition to testing the harvested flowers, manufactured products, and ingredients used to make the finished products.
Which heavy metals are commonly found in cannabis?
Among the most common heavy metal contaminants found in cannabis include:
Arsenic
Cadmium
Chromium
Lead
Mercury
At our New Jersey analytical laboratory, True Labs for Cannabis tests for the above heavy metals as per New Jersey’s interim testing standards following those defined by the Maryland Medical Marijuana Commission. These heavy metals are found in natural ecosystems and could potentially lead to contaminated cannabis products. Many heavy metals are common in fertilizers, which makes them particularly concerning in agricultural applications, including cannabis cultivation. Other heavy metals which True Labs for Cannabis has the capability to test for include, but are not limited to:
Antimony
Barium
Cobalt
Copper
Iron
Manganese
Molybdenum
Nickel
Selenium
Silver
Thallium
Vanadium
Zinc
Do states require heavy metals testing?
Many states require cannabis companies to test their products for heavy metals before the products can be sold to the general public. Here are some states that require heavy metals testing, and which metals a testing lab is required to screen:
California: Starting in 2018, the California Bureau of Cannabis Control requires flower, other inhaled products, and other cannabis extracts to be tested for four heavy metals: Lead (Pb), cadmium (Cd), mercury (Hg), and arsenic (As). These four are the baseline in many states because they are Class I metals as determined by the U.S. Food and Drug Administration (FDA), which means that they can be particularly hazardous to human health.
Colorado: As of 2019, the state’s Marijuana Enforcement Division requires testing for lead, cadmium, mercury, and arsenic. The law does not require screening for other heavy metals, but it is encouraged. In 2020, the state announced its first recall of cannabis products with too-high levels of heavy metals.
Maryland: These standards are particularly important for New Jersey cannabis operators, as the Garden State is utilizing Maryland’s standards as a starting point for developing their cannabis testing requirements.
Does New Jersey require heavy metals testing?
Yes. New Jersey’s legal medical and adult-use cannabis producers must test their products for heavy metals. While the adult-use regulations are still under development as of summer 2021, medical marijuana continues to be tested for heavy metals, and it is widely expected that several heavy metals will be on the list of required contaminants for which to test going forward in the legalized market.
How cannabis testing facilities check for heavy metals
Inductively coupled plasma mass spectrometry (ICP-MS) is one of the most effective ways to test for heavy metals in cannabis samples. This highly sensitive machinery is well known for its sensitivity, precision, and speed for detecting very small, trace amounts that are well below the acceptable limits in most states. With the ICP-MS, the machine turns the sample of cannabis into much smaller polyatomic ions, which are then tested for the heavy metals in question. Before the ICP-MS became the gold standard for cannabis testing facilities, analytical laboratories had to break down the sample and extract heavy metals from it for further analysis.
Trust True Labs for Cannabis for heavy metals testing
As one of very few laboratories in New Jersey to solely service the cannabis and hemp industries, True Labs for Cannabis (TLC) is committed to bringing the highest caliber of service and scientific accuracy to cannabis businesses throughout the Garden State. Our lab partners with processors and cultivators to test cannabis for many harmful heavy metals, detecting these toxins in amounts as low as one part per trillion. Learn more about TLC’s heavy metals testing procedures and how our experts can ensure you’re offering the safest and cleanest possible cannabis flower, extracts, and edibles to patients and customers.