Removing Pesticides from Concentrates
1. This article describes the current state of pesticide prevalence in the cannabis industry and how Flash Chromatography may be used to remove residual pesticides from concentrates. Be aware that the author of this article represents a company that manufactures and sells Flash Chromatography equipment.
2. Cannabis and Hemp, as with other other crops, are plagued by numerous pests. Unlike other crops, their decades old prohibition have created an unmet demand for approved pesticides. As a result many growers are resorted to, quote – treating their plants with alarmingly high levels of pesticides intended for other uses – unquote.
3. Cannabis growers in California often rely upon pesticides such as, quote – avermectin, myclobutanil, and bifenazate. Exposure to these chemicals has proven proven toxic or even carcinogenic – unquote. 4. A high percentage of concentrates tested had pesticides present. One cannabis concentrate tested exhibited, quote – 415 parts per million … carbaryl … by comparison, the tolerance for carbaryl on blueberries is three parts per million – unquote.
5. Similarly high rates of Myclobutanil, used to prevent powdery mildew, were seen as high as 392 ppm where other food items are typically regulated to have less than 10 ppm.
6. Many of the recreationally and medically legal cannabis states have regulations limiting the presence of certain pesticides to between 100 ppm and 2,000 ppm depending on the compound. Typically, products found to be in violation are required to be destroyed if a viable remediating method is not available.
7. As a result, the Cannabis and Hemp industries have a great need, and financial incentive, to remove pesticides from their concentrates. Flash Chromatography may offer a viable solution.
8. Chromatography has long been used in pharmaceutical applications to purify target substances; quote – based on compound polarity, … [it is a way] to purify a complicated mixture such as cannabis concentrates – unquote.
9. Flash chromatography is similar to other forms of chromatography but it incorporates low to medium pressure gas to force the mobile phase through the column, greatly reducing overall separation time. 10. The author cites a study performed using a Buchi Reveleris X2 Flash Chromatography system to remove pesticides from cannabis concentrates.
11. Results of the investigation showed that, quote – total pesticides have been reduced from 365,854 ppb to 708 ppb – unquote. The quoted statistic is somewhat misleading because over 300,000 ppb was present in the form of one specific compound, but of the seven offending contaminates in the sample, all but one were reduced below the 200 ppb threshold.
12. Permthrin was found at a rate of 353 ppb after the separation, most likely due to, quote – this compound’s polarity closely resembling the of THC – unquote. It is believed that further process refinement will allow the Permthrin to be reduced below the test threshold.
13. If this test is indicative of Flash Chromatography’s ability to separate out cannabis and hemp extract contaminates and is able to be performed at a industrial scale, it may be a viable method to reclaim pesticide laden product.
Source: Zhou L. Removing Pesticides from Cannabis Concentrates. Terpenes and Testing. https://terpenesandtesting. com/cannabis-concentrates-pesticides/. Accessed February 13, 2019.
Review by: SP