Analysis of Pesticides and Mycotoxins in Cannabis Brownies

Author: Nathaly Reyes and Colton Myers

Published By: Restek Corporation

Year of Publication: 2020


Abstract: Government regulations in California require the cannabis industry to test edible products for an extensive list of pesticides and mycotoxins. Here, an effective workflow for this complex analysis was developed in brownies and optimization strategies are detailed in order to provide a starting point for similar matrices. Both LC-MS/MS and GC-MS/MS were employed and excellent results for LOQ, linearity, accuracy, and precision were attained for all the target compounds.

Residual Pesticides Analysis of Botanical Ingredients Using Gas Chromatography Triple Quadrupole Mass Spectrometry

Author(s): Riki Kitano1, Tairo Ogura1, Nicole Lock1, Robert Clifford1, Julie Kowalski2, Jack Cochran2, Dan Li2
1. Shimadzu Scientific Instruments, Inc. 2. Restek Corporation

Published By: Restek Corporation

Year of Publication: 2019


Abstract: Dietary supplements, which are consumed worldwide, are made from various botanical ingredients. To be safe from pesticides exposure, residual pesticides must be monitored by chromatographic instrumentation. Issues arise, however, due to the fact these botanical samples are dried and cause large interferences in the chromatography. This study shows that the modified QuEChERS method combined with GC-MS/MS achieves consistent pesticides monitoring in botanical ingredients.

Acknowledgment(s): Originally published by Shimadzu Corporation in collaboration with Restek Corporation.

New Pesticide CRMs Released Specifically for Cannabis Labs in California and Similar States

Restek’s support for cannabis-testing labs continues to grow. This latest offering will help you meet the specific cannabis analysis needs of California set forth by the Bureau of Cannabis Control for regulated category I and II residual pesticide reporting—and of other states with similar regulations/programs. Ideal for creating multipoint (5-point minimum suggested) calibration curves for GC- and LC-MS/MS, these six mixes of prepared stock standards also eliminate the need for in-house standards preparation. And, as with all certified reference materials (CRMs) manufactured and QC tested in Restek’s ISO-accredited labs, they will satisfy your ISO requirements.

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New Oregon Cannabis Pesticide Standards—Injecting Confidence in Your Analysis

Restek is pleased to announce the launch of new pesticide residue standards to meet the specific cannabis analysis needs of Oregon—and states with similar pesticide residue regulations/programs. Dissolved in acetonitrile and formulated for stability, the 59 compounds are separated into 6 x 1 mL solutions with individual analyte concentrations of 600 μg/mL—resulting in a convenient 100 μg/mL solution when blended immediately before use. Designed with quality and convenience in mind, this set of standards eliminates the need for in-house standards preparation. Restek’s Oregon pesticide standards are certified reference materials (CRM) manufactured and QC-tested in ISO-accredited labs.

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Using Method Detection Limits to Set Mandatory Reporting Limits for Banned Pesticides: How a Public-Private Partnership Improved Cannabis Regulation in Colorado

Author(s): Joseph Konschnik1, Heather Krug2, Shawn Kassner3
1. Restek Corporation, 2. Colorado Department of Public Health & Environment (CDPHE), 3. Neptune and Company, Inc.

Published By: Cannabis Science and Technology

Issue: 1

Year of Publication: 2018


Abstract: The discovery of nonregistered pesticides contamination in cannabis plant material in Colorado prompted the need to set mandatory reporting limits (MRLs) for these pesticides in the state to ensure public safety. Since then, the Colorado Department of Public Health and Environment (CDPHE) undertook the responsibility for setting such MRLs. Colorado’s novel approach to determine MRLs for each pesticide involved forming a working group with its in-state laboratories and expert volunteers to agree on analytical procedures to determine method detection limits (MDLs) using an industry-standard approach. The authors describe how this approach formed a collaborative public-private partnership where state government agencies worked side by side with laboratories and growers toward a common goal. The multilaboratory study was completed yielding MDLs for 13 pesticides in cannabis flowers using a QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction with analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The authors share the procedures used for the study, an overview of the data generated by the participating laboratories, and the new Colorado MRLs, which became effective on January 1, 2018.

The Practical Chemist: Calibration – The Foundation of Quality Data

Author: Amanda Rigdon
Restek Corporation

Published By: Cannabis Industry Journal

Year of Publication: 2016


Abstract: This column is devoted to helping cannabis analytical labs generate valid data right now with a relatively small amount of additional work. The topic for this article is instrument calibration – truly the foundation of all quality data. Calibration is the basis for all measurement, and it is absolutely necessary for quantitative cannabis analyses including potency, residual solvents, terpenes, and pesticides.

Determination of Emerging Contaminants in Wastewater Utilizing Comprehensive Two-Dimensional Gas-Chromatography Coupled with Time-of-Flight Mass Spectrometry

Author(s): Sarah Prebihalo1, Adrienne Brockman1, Jack Cochran1,2, Frank L. Dorman1,3

1. Pennsylvania State University, Forensic Science Program
2. Restek Corporation
3. Pennsylvania State University, Department of Biochemistry and Molecular Biology

Published By: Journal of Chromatography A

Year of Publication: 2015


Abstract: An analytical method for identification of emerging contaminants of concern, such as pesticides and organohalogens has been developed and utilized for true discovery-based analysis. In order to achieve the level of sensitivity and selectivity necessary for detecting compounds in complex samples, comprehensive gas chromatography coupled with time-of-flight mass spectrometry (GCxGC-TOFMS) was utilized to analyze wastewater samples obtained from the Pennsylvania State University wastewater treatment facility (WWTF). Determination of emerging contaminants through a process of combining samples which represent “normal background” and comparing this to new samples was developed. Results show the presence of halogenated benzotriazoles in wastewater samples as well as soil samples from Pennsylvania State University agricultural fields. The trace levels of chlorinated benzotriazoles observed in the monitoring wells present on the property indicate likely environmental degradation of the chlorinated benzotriazoles. Preliminary investigation of environmental fate of the substituted benzotriazoles indicates their likely degradation into phenol; an Environmental Protection Agency (USEPA) priority pollutant.

Cannabis Testing Opens Up a Whole New Market

Author(s): Michelle Taylor, Editor-in-Chief
Chromatography Techniques / Laboratory Equipment

Published By: Chromatography Techniques / Laboratory Equipment

Year of Publication: 2015


Abstract: Given recent law and attitude changes in the United States, the cannabis industry is on the rise — which means the cannabis testing industry is likewise growing. From analyzing potency and pesticides to testing for terpenes and residual solvents, chromatography is aptly suited to the analytical needs of the cannabis testing industry. Chromatography Techniques Editor-in-Chief Michelle Taylor recently spoke with Amanda Rigdon, GC Columns Product Manager at Restek Corp., for her input on the past, present and future of the cannabis testing market.

High-Quality Analysis of Pesticides in Cannabis Using QuEChERS, Cartridge SPE Cleanup, and GCxGC-TOFMS

Author(s): Jack Cochran, Julie Kowalski, Sharon Lupo, Michelle Misselwitz, and Amanda Rigdon
Restek Corporation

Published By: Restek Corporation

Year of Publication: 2014


Abstract: As medical cannabis is more frequently prescribed, patient safety must be ensured. Pesticide residue testing is an important part of assuring safe product is dispensed, but analysis can be extremely challenging due to matrix complexity. The use of QuEChERS, cartridge SPE cleanup, and GCxGC-TOFMS as presented here produces high-quality quantitative data for this difficult analysis.