Despite regulations that mandate that cannabis products be tested for pesticides, there isn’t a standardized list of allowed or banned products. What fails in one state can pass in another. There are also “acceptable” levels of pesticides, as per the regulations, that may not be desirable for consumption. What would be ideal is the ability to eradicate one’s usage of pesticides all together, such that contamination, whether trace levels or higher, is never a worry. This may sound utopian, but some companies in the industry envision just this scenario.
I spoke with Carlos Perea, CEO and co-founder of Terra Vera to learn more.
JSL: If analytical labs are testing for a suite of pesticides, how is contaminated product making it to market? Is it from cherry picking specific flowers to send for testing, or not enough biomass actually being tested from a specific batch?
Carlos Perea: While most all states regulate pesticidal residues, the actual rules and regulations vary dramatically for each state. In some states, the tests are voluntary and not tracked. In other states, there are ways to work around the system by how samples are collected and processed. The challenge of quantifying pesticide residues in cannabis is complex and there is some testing variability state to state and lab to lab.
And, of course, there is still illicit sourcing of flower, as well as other unregulated products making their way to dispensary shelves as well as street corners. There are many recent studies and investigative news stories of tainted product being found on dispensary shelves as well as several official product recalls for cannabis products that have tested positive for toxic insecticides and fungicides. Unfortunately, even a small exposure to these banned substances can pose serious health risks, especially to consumers who are immunocompromised.
JSL: How much product would you say is contaminated with pesticides and how does inhaling flower or concentrates tainted with these pesticides affect the end user?
CP: It is hard to track and likely varies dramatically state to state and over time, but many educated estimates put the percentage of tainted product at 20% or more. As an example, when California implemented mandatory pesticide testing in 2018, the initial findings were that more than 24% of products tested failed the standards. Even a small percentage risk is too much and can pose serious health issues to those unfortunate enough to consume tainted product. Prior to 2015, the use of myclobutanil, a fungicide that reduces mildews on plants, was fairly common. Regulators in Colorado took notice and investigated the toxic risks of this chemical that is prohibited for use in tobacco cultivation. What they found is that once this chemical is heated, as in combustion of flower, it can generate hydrogen cyanide, which was used in chemical warfare during World War I. There are many other pesticides that can pose serious risks not only to consumers, but to the environment as well. And even when the toxicity and dose from tainted product isn’t enough to cause serious risks, it almost always leads to a worse consumer experience, as it can still cause physical issues and ailments such as rashes, irritated eyes, and lung irritation.
JSL: Which pesticides are the most common offenders?
CP: Because the regulations and grow conditions vary so much from state to state, there are many pesticides to be concerned about, including some that are actually allowed under state regulations. In 2018, Massachusetts health regulators closed two medical cannabis dispensaries after a test came up positive for bifenthrin, a pesticide linked to cancer. And in a CNN report of Colorado’s products, they found one in six shelf samples to test positive for a neurotoxin called imidacloprid which can cause issues with your central nervous system and is linked to the deaths of hundreds of animals after being treated with products that contain this chemical.
In California, law enforcement has found evidence of widespread use of carbofuran, a pesticide that is known to be toxic to wildlife and humans as it can cause permanent damage to reproductive systems. One of the more frequently used, and accepted, pesticides in cannabis production is neem oil, a naturally occurring pesticide found in seeds of the neem tree. The active component of this pesticide is azadirachtin, which has also raised certain health concerns.
JSL: What kinds of cultivation methods can be employed to minimize the use of pesticides?
CP: There are many important steps growers can take to minimize the risk of unwanted pathogens or pest pressure. Of course, it helps to have a high quality, grow environment where the grower can control the temperatures, humidity, and other factors with some precision. And genetics selection can play a role as well, as some cultivars are more likely to have mold or mildew issues than others depending on the grow conditions. But the key factor in any quality grow is to have a systematic approach to pest management, or an IPM (integrated pest management) protocol. This includes treatments done at each stage of the cultivation process and this also typically spells out steps for how to keep the facility clean and at a relatively low risk of infection. But even the best growers and most expensive grow facilities can’t completely eliminate the risk of pest pressure. When molds, mildews, and other unwanted pathogens emerge, it is best to treat quickly and proactively with methods that will remediate the issue and prevent future outbreaks.
JSL: How can specific changes to cultivation practices mitigate pest infestations that would normally cause one to turn to legal or illegal pesticide use?
CP: The old adage, an ounce of prevention is worth a ton of cure, certainly applies. Effective IPM practices are focused on prevention rather than treatment of infected plants. This also requires constant attention to monitoring the health of the plant as well as the risks of infection from unwanted microbial pathogens. Some of these pathogens are difficult to detect until they have infected the plant and caused crop damage or worse. Powdery mildew (PM) is one of the more common issues growers face and is often an issue when there are other crops nearby or when growers face challenges with humidity control. Fortunately, there are emerging treatment methods, like Terra Vera, that can both eliminate unwanted PM and prevent future outbreaks.
JSL: How can organic farming help supplant the use of pesticides?
CP: Organic farming is quickly gaining in popularity for traditional food crops as consumers have shown they are willing to pay more for produce that is pesticide-free. Cannabis growers can’t claim organic status because the crop is still federally illegal, so organic standards can’t be applied. However, cultivators can take the same steps to grow products with organic methods without the use of synthetic pesticides. Moreover, just like with food crops, cannabis users have shown a strong preference for quality products that are pesticide free.
JSL: What are some natural alternatives a cultivator can turn to?
CP: There is an increasing list of natural products and methods for cultivators to use as part of their IPM. These include beneficial microbes as well as friendly insects that can control unwanted bugs. However, growers need to be mindful not only of what is approved for use in their state, but what will be effective at controlling the contaminants that can damage or destroy crop value. It is a fine line for most growers where they want to keep treatments to a minimum and, at the same time, not risk their crops. In general, many growers turn to oils, like neem oil. While some of these do have some efficacy, they can also have unwanted effects such as coating the plant, which can inhibit healthy transpiration and other biological processes.
JSL: How does your technology work?
CP: We believe that it is hard to beat nature at finding effective ways to combat unwanted issues like microbial contamination. Our technology is biomimicry in nature, meaning we are using technology to recreate a chemistry that occurs naturally in our immune system. To put it another way, we didn’t invent a new chemistry; rather we developed a way to create the same chemistry our bodies produce naturally when fending off unwanted pathogens such as harmful bacteria or even viruses. It turns out that this chemistry is not only benign to humans and wildlife, it is also fairly gentile to plants. At the same time, it is proving amazingly effective at remediating and preventing many issues that challenge growers including botrytis, PM, and most of the common microbial issues like Aspergillus and other common molds, mildews, and bacteria.
JSL: How have other markets already utilized this technology?
CP: We found this technology being used very effectively in water treatment for microbials. It was originally developed for making water safe to drink and has been used by the US Navy, as well as soft drink manufacturers, and even public drinking water systems all over the world. We found a new way to use this proven technology for agricultural applications starting with helping cannabis growers produce the best possible crops without the need for using potentially toxic synthetic pesticides. Indeed, the overarching reason we started Terra Vera was to help growers of all types of crops eliminate the need to use chemicals that can poison our food supply and damage our environment. We believe there are better ways to grow sustainable crops and we want to ensure our children and our children’s children are not dealing with the cancers, reproductive issues, and early onset of degenerative diseases like Alzheimer’s which are linked to pesticidal use.
JSL: How achievable is a pesticide-free cannabis industry?
CP: While sensible and more consistent regulations will help, I am believer that the best driver of moving to a pesticide-free industry are the consumers themselves. They should be able to make informed decisions and know what they are consuming. This starts by asking for certificates of analysis when they purchase products. Many states require that dispensaries make this information available. When surveyed, 92% of consumers said they want their cannabis to be free of pesticides and 85% said they want their product to not be subjected to irradiation, a method used as a final kill step to ensure there are no harmful bacteria or other microbial risks. The best cultivators will find ways to meet these consumer demands. Even when they aren’t required to, the best growers will be transparent about how they grow and treat their products. I believe these operators will be rewarded by the market and be the first to gain solid brand loyalty and appeal.
