Recipient Organization
CONNECTICUT AGRICULTURAL EXPERIMENT STATION
PO BOX 1106
NEW HAVEN,CT 06504
Performing Department
Analytical Chemistry
Non Technical Summary
The 2018 farm bill removed hemp, defined as Cannabis sativa, with less than 0.3% delta-9 tetrahydrocannabinol (THC), from the schedule I controlled substances list. Cultivation of hemp began in Connecticut (CT) in 2019. Hemp growers in CT have primarily focused on the production of cannabidiol (CBD) which is in high demand for its potential role in easing symptoms of many common health issues, including anxiety, depression, acne and heart disease. In other areas of the country hemp may be grown for seed or oil. There is the possibility that pesticides may intentionally or unintentionally be applied during the production of hemp for CBD, seed or oil. The goal of this work is to determine to what extent pesticide residues end up in products intended to be ingested by the consumer.The Connecticut Agricultural Experiment Station (CAES) is an International Organization for Standardization (ISO) 17025 accredited laboratory for pesticide residue analysis in food. It has worked with the CT Department of Consumer Protection (CT DCP) since the 1963 and is the de facto laboratory to provide regulatory enforcement of pesticide residues in food sold within the state. Since 2019 the CAES has worked collaboratively with the CT Department of Agriculture (CT DoAg) to test hemp grown in the state for THC content prior to harvest. The CAES methodology used for food testing will be applied to the testing of Cannabis sativa bud, leaf and seed. The method will be validated to first ensure that pesticides of interest can be appropriately tested in the hemp matrix. Work will then examine how effectively pesticide residues are co-extracted during the purification of the CBD, and if they ultimately end up products available to the consumer.
Animal Health Component
0%
Research Effort Categories
Basic
100%
Applied
0%
Developmental
0%
Goals / Objectives
Agronomic practices -Determine effects on grain, fiber, or dual-purpose productivity as functions of * Cultivars - including suitability to growing conditions/regions. This entails evaluating and developing adapted, improved, monoecious cultivars for grain, fiber, dual purpose (grain + fiber), and essential oil production systems across the USA.
* Soil types
ÿ Suitability/adaptability to varied soil types, including disturbed and marginal soils
* Establishment practices
ÿ Conventional tillage vs. no-till establishment
ÿ Planting date ÿ¿ variety interactions
ÿ Planting rates (and depths) appropriate for fiber and seed crops
ÿ Row spacing
* Fertilization practices
ÿ Application rates
ÿ Application timing (especially relative to different production outcomes (grain, fiber, dual purpose (grain + fiber), and essential oil production systems)
* Canopy management
ÿ Utility/timing of topping during growing season to induce multiple tillering
* Water use and demand
ÿ Irrigation ÿ¿ variety interactions
ÿ Evapotranspiration and water demand
ÿ Timing availability effects
* Insect, pathogens, and other pest management.
ÿ Pest and pathogen sensitivity
ÿ Efficacy of seed fungicide and insecticide treatments
ÿ Effects of late-season fungicide applications on grain yield and quality
ÿ Economic thresholds for insect and other pest control
* Weed management
ÿ Pre/post emergence herbicides for weed control
ÿ Herbicide sensitivities
* Harvest and handling practices
ÿ Evaluate efficacy of field desiccation (e.g., using diquat or glyphosate) for grain crops
ÿ Develop best practice protocols for retting both in fiber and dual purpose hemp systems
ÿ Determine engineering needs for harvest, handling and processing
* Suitability for crop rotations
ÿ Evaluate potential for use in rotations or mixtures with other crop
ÿ Measure hemp performance and weed/insect/disease incidence following corn, cotton, soybean, tobacco, forage/pasture/range/fallow
ÿ Determine hempâ¿¿s effects on disease/pest cycles of other crops
Project Methods
The 2018 Farm Bill fostered the introduction of hemp and many hemp-derived products into the food stream. As hemp is produced, harvested and dried there is the potential that pesticides may be applied intentionally or inadvertently through drift or cross-contamination. This raises the concern that pesticide residues may be found in hemp and/or hemp derived products that are intended for human use or consumption such as cannabidiol (CBD), seed and seed oil.The Connecticut Agricultural Experiment Station (CAES) has a long history of testing pesticides in food in Connecticut (CT). It has worked with the CT Department of Consumer Protection (CT DCP) since the 1963 and is the de facto laboratory to provide regulatory enforcement of pesticide residues in food sold within the state. Owing to the 2011 Food Safety Modernization Act (FSMA) the CAES attained accreditation to the International Organization for Standardization (ISO) 17025 standard in 2016 for the analysis of pesticide residues in foods.The CAES has experience employing the "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) method which is based on an acetonitrile/water partition and employs a dispersive solid phase extraction cleanup prior to analysis by gas and liquid chromatography with mass spectral detection (GC/MS) and (LC/MS). A total of 349 pesticide analytes (196 LC; 190 GC) have been validated in 30 different commodities / matrices (3 commodity groups; high water content; high acid and high-water content; high oil and intermediate water content) as part of our ISO 17025 accreditation.Given the increased amount of hemp and hemp-derived products in the marketplace, the concern over potential contamination of those products, and the experience of the CAES in analyzing these compounds, it is logical a validated method for these analytes in hemp be developed.The QuEChERS based approach used at the CAES will be applied to hemp bud, leaf and seed and / or hemp derived products. Once the method has been appropriately investigated, a single laboratory validation of the method will be performed working within the ISO 17025 guidelines. The detection limits, accuracy, reproducibility, and ruggedness of the method will be examined.To determine how prevalent pesticide residues might be in hemp grown in CT, largely as a result of potential spray drift, samples of hemp brought in from growers for delta-9 tetrahydrocannabinol (THC) testing can be tested for pesticide residues. Many hemp growers in CT currently submit samples to the CAES for the analysis of THC prior to harvest as required by the CT Department of Agriculture (CT DoAg).Hemp production is under study by the CAES at our Lockwood farm. A plot of hemp was planted in 2019, and again in 2020 to study various aspects of growth and production. This plot provides a unique opportunity to apply pesticides and allow weathering in the field to occur prior to harvest and analysis. This approach allows for the examination of field incurred pesticide residues. In addition it servesas a source of hemp for investigational laboratory studies. The test plot at the Lockwood farm also serves as an outreach and educational tool to the public and hemp growers. The CAES hosts an annual Plant Science Day (PSD) event. The CAES invites CT residents and interested parties to the farm to observe the field plots and to interact with scientists.Hemp growers in CT have primarily focused on the production of cannabidiol (CBD) owing to its high value as a commodity crop. Hemp derived cannabidiol (CBD) is in demand for its potential role in easing symptoms of many common health issues, including anxiety, depression, acne and heart disease. Pesticide residues may adulterate food by being carried along through the CBD extraction process from the hemp plant. As such it may be incorporated into oils and foods intended for human consumption.The fate of pesticide residues in the first step of most purification processes of CBD which is an ethanolic extraction will be examined. Either field or laboratory incurred residues on hemp will be extracted with ethanol at various temperatures and conditions. These extracts willand analyzed by our laboratory validated method for pesticide residues. The information obtained from these analysis will be valuable in determining potential health implications for pesticides in hemp derived product.After establishing the efficiency at which various pesticide residues are extracted into ethanol, the project can move forward, applying the QuEChERS based analysis method to commercially available CBD products for pesticide residue analysis. These efforts will help lead to a clearer understanding of how effectively pesticide residues on hemp may end up in products ingested by the consumer.