Pesticide Use on Cannabis
1. This article was published by the Cannabis Safety Institute, but with the recent passage of the 2018 Federal Farm Bill, legalizing the production of Industrial Hemp, much of the research and discussion will be applicable to the fledgling Hemp industry as well.
2. Cannabis and Hemp are susceptible to damage from a variety of mold and insects which has been exacerbated by, quote – the recent surge in sales of immature clones [which] has spread plant diseases widely across several states – unquote.
3. The high crop value coupled with pest susceptibility has lead to widespread pesticide use.
4. Of particular health concern, most pesticides that are approved for food crop production are tested and regulated based on oral toxicity. Many cannabis and hemp product are ingested through smoke inhalation, little research has been done to define the toxicity of pesticide inhalation.
5. Although, the inhalation toxicity is not well defined, quote – research has shown that pesticides on cannabis can be transferred into cannabis smoke with efficiencies as high as 70 percent – unquote.
6. Research conducted for this investigation concluded that pesticides were present, quote – on close to half of the Cannabis sold in Oregon dispensaries – unquote.
7. Since Cannabis is still regulated as Federally Controlled Substance, pesticide use on Cannabis is not currently regulated by the EPA or USDA. Making it especially difficult for Cannabis and Hemp growers is the fact that most commercial agriculture pesticides are legally restricted in their use to applications specifically listed on their data sheets.
8. The decades old prohibition of cannabis and hemp production prevented pesticide producers from seeking approval for products to be used on these crops, as such none include cannabis and hemp on their labeled uses. This prevents cannabis and hemp producers from legally using many common pesticides that may be both safe and effective.
9. Many of the recreationally and/or medically legal cannabis states have implemented their own set of pesticide regulations, but this has not been done in the most effective manner.
10. Oregon state has regulated that, quote – all marijuana be tested for … four classes of pesticides [which] are actually composed of … 491 individual compounds – unquote. As such, for any marijuana product to be in compliance with state law it would have to be tested for 491 different compounds, all of which must be below the 0.1 ppm threshold.
11. This legislation has two major drawbacks, testing for nearly 500 compounds is prohibitively expensive, and some potentially detrimental compounds that could be used by the cannabis and hemp industries do not fall with in the 4 classes of regulated compounds. Ultimately, the regulated compound lists was not well defined in terms of applicability to the cannabis and hemp industries.
12. This extensive, yet vague, regulation offered growers little insight into safe and effective pest control use. It also, quote – led to a vigorously expanding testing industry in which most labs were using inappropriate techniques to screen for arbitrarily chosen lists of compounds – unquote.
13. This has led to customer products were labeled as pesticide-free when in fact it is likely that other non-regulated compounds, of equally concerning toxicity, were present.
14. One of the authors is the director for a licensed and qualified marijuana analysis facility in Oregon. This study collected data from 154 Cannabis flower samples and tested for 65 compounds. Their list of 65 compounds was determined through extensive interviews with growers and grow supply employees as well as a survey of online cannabis grower forums and instructional sites. Compounds listed by the USGS for similar crops and applications were also included. A list of these compounds is found on page 7.
15. Of the flower tested, 29 percent had detectable residue. Based on EPA regulation for other crops 14 percent would have been failed. They also tested cannabis extracts which tends to concentrate pesticide content: 55 percent of extracts had pesticide content and 46 percent would fail EPA regulations.
16. The authors of this study make specific recommendations to improve the safety and efficacy of pesticide use in the Cannabis industry on page 16. They also offer a list of 123 compounds on page 18-19 which are most in need of investigation for regulation. Ultimately, Federally allowing the EPA to regulate the cannabis and hemp industries will go the furthest towards defining the safe application of pesticides.
Source: Voelker R, Holmes M. Pesticide Use on Cannabis. Cannabis Safety Institute. June 2015. https://cannabissafetyinstitute.org/wp-content/uploads/2015/06/CSI-Pesticides-White-Paper.pdf. Accessed February 11, 2019.
Review by: SP