Heavy metals in cannabis can be a dangerous thing (click here for more on their impact on quality and safety), so you’ll want to prevent their presence, and eradicate them if they make their way into your grow. In this Q&A with Advanced Nutrients’ Michael “BigMike” Straumietis, learn how to make sure your product is devoid of heavy-metal contamination.

Cannabis Business Times: What are the first steps cultivators can take to gain more knowledge about possible heavy metals in their crops?

“BigMike”: The easiest thing for cultivators to do is to buy only registered fertilizer products, from reputable stores, which have, at the very minimum, met the heavy metals requirement for registration in your state.

Second, understand that all of the environmental inputs-—fertilizers, growing media, and even the clone/plant itself—contribute to the final heavy-metal concentration of the final product. Finally, one could review the heavy-metals contents of the fertilizers present on California, Oregon and Washington state websites. However, it’s important to keep in mind you will not find supplement products on the Washington website at all because it’s not a requirement there. But that doesn’t mean those are not legal or good products, it’s simply because the state doesn’t register these kinds of products. Someone in Washington could look at the California Department of Food and Agriculture (CDFA) or Oregon Department of Agriculture (ODA) websites for those kind of products.

CBT: Provide a few examples of labs that can provide this type of testing.

BM: Because there are no cannabis-specific heavy-metal testing labs as of yet, environmental labs and water-quality testing labs are viable. These are the types of labs that do testing on pipes and water in pipes to see if metals are present. These environmental labs are able to do the testing. None of the cannabis analysis labs are offering heavy-metal testing at this time.

CBT: How often should cultivators test for heavy metals?

BM: Cultivators should test for heavy metals any time major changes occur in a growing environment, such as new growing mediums, new strains and new fertilizers. Cultivators should also test based on requirements in their jurisdictions (with some jurisdictions requiring that every crop be tested).

Above: Cannabis plant grown with Advanced Nutrients

CBT: What is the cost associated with heavy metal testing?

BM: It’s not all that expensive, and the costs will continue to decline as it becomes more common practice. Depending on how many metals you are looking to have analyzed, a reputable environmental lab can do the testing for $200 to $350 per test.

CBT: How has testing for heavy metals evolved over recent years?

BM: As years have gone by, the U.S. Food and Drug Administration (FDA) has increased testing on all inhalable products. The list of possible contaminates continues to grow, and heavy metals are included in that list. More and more attention is now being paid to our industry as well. The technology has greatly improved, too. Detailed testing using ICP (Inductive Coupled Protoplasma) analysis is newer and more detailed than the older AAS (Atomic Absorption Spectroscopy) methods. The introduction to ICP testing allows for a better understanding of what is in a vapor or in soil that may contain harmful metals. These methods are far more accurate, and the detection levels are way lower.

Images courtesy of Advanced Nutrients

