Cannabis testing is a crucial step in ensuring the safety and quality of cannabis products before they enter the retail market. Here, we take a step by step guided tour of a virtual cannabis lab and provide an overview of the journey of a cannabis sample from collection right through to the production of a certificate of analysis.
annabis laboratories are modern, tech-heavy facilities equipped with sensitive
analytical instrumentation and qualified, competent technicians and analysts trained for each type of
test conducted. Analysis often utilizes organic solvents like methanol and acetonitrile, or corrosive
liquids like nitric acid and hydrochloric acid. Therefore, chemical fume hoods are required to ensure
employee safety, along with safety glasses, gloves, and lab coats. Security is paramount at these
facilities, and all activity occurs in designated areas under video surveillance. When not being
handled, samples are retained in a secure storage location with restricted access to authorized
pon request by the licensee, laboratory personnel are dispatched to the cultivation
or processing site to collect representative samples. The field samplers arrive on-site with fresh
personal protective equipment (PPE) including gloves, lab coat or coveralls, often hair coverings,
disposable bootie coverings, and surgical masks. Field sampling kits accompany the samplers, often as
carry-on sized hard-shell rolling cases, sanitized before each sampling site. A field balance is
verified with reference weights to ensure proper functionality and accuracy, and the sample increments
are randomly selected from the batch, weighed, and recorded on chain-of-custody (CoC) paperwork. Upon
completion of the sampling event, the representative samples with documented masses are relinquished by
the licensee’s signatory, and the field samplers assume custody of the product for secure transport to
the designated laboratory.
pon arrival at the laboratory, samples are immediately examined to document
integrity. This intake process ensures the sample has not experienced tampering or adverse conditions
during transport. Typically, temperature minimum/maximum is documented by a device that travelled with
the samples, and sample packages are scrutinized to verify the tamper-evident seals have not been
broken, altered, or replaced, and no spillage, leakage, or other mishandling has occurred. Staff
accepting the samples verify that the recorded mass or number of units, and matrix type, exactly match
the CoC paperwork. Once samples are deemed acceptable, custody is transferred to the laboratory by
signature of the field sampler and sample acceptor. Samples are registered in the laboratory information
management system (LIMS), assigned a unique internal laboratory ID, and staged for visual inspection and
further sub-sample allocation to the various assays.
Visual inspection is specifically defined by each state’s governing body, and often includes thresholds for debris such as dirt, cinders, hair, insect parts, animal excrement, and mold. Typically, a lab uses a device to magnify an image of the sample during inspection, such as a standard stereomicroscope or modern handheld digital USB mini-scope. Either option gives ample visual magnification to conduct visual inspection. This examination is generally carried out prior to sample homogenization, in order to identify debris before it would otherwise be non-recognizable, mixed in with the botanical matrix.
ample preparation varies according to the analytes being measured. In general, the
entire representative sample is mechanically homogenized (after visual inspection is complete). The
homogenization process ought to be conducted in a sterile manner when microbiological testing will be
conducted downstream. Sub-samples are then weighed into appropriate vessels, and an extraction liquid is
added to mobilize the product constituents, and potentially contaminants, into the liquid media
(solvent, acid, or buffer). Typically, this extract is further diluted into a test aliquot for analysis.
annabis is tested to provide a measure of quality to the supply chain and ultimately
the end-user. Regulatory testing generally requires potency measurements so the product can be labelled
to inform the consumer, and also requires screening for residual contaminants such as pesticides, heavy
metals, processing chemicals, and microbes or microbial by-products, according to public-health
esticide residuals on harvested cannabis plant material is a result of human
application or plant uptake from the environment. Mycotoxins are generally present when particularly
nefarious species of molds are present during cultivation, harvest, curing or storing phases of
production. Nevertheless, these both of these types of small molecules are typically tested by utilizing
methodology carried out by liquid chromatography tandem mass spectrometry (LCMS/MS). Gas chromatography
tandem mass spectrometry is also applicable in states with pesticide analytes not amenable to LCMS/MS.
These highly sophisticated, incredibly sensitive instruments are necessary due to the extremely low
quantities required for detection limits by many states.
hen raw cannabis plant material is extracted, concentrated, or otherwise processed
into oil, the process often utilizes butane, propane, ethanol or other chemical solvents as the carrier
for the target cannabinoids and terpenes. To determine if residual processing chemicals are present in
excess of the state action limits, test aliquots are partitioned into headspace vials and run on (GC)
instrumentation. Along with the extraction constituents such as butane, this assay also screens for
minute levels of contaminants such as benzene, chloroform, toluene, and xylenes.
pon completion of all required laboratory testing, the product data are evaluated
against the action limit criteria. Test samples with no detections over any of the contamination limits,
and within potency claim margins, are deemed to pass and released in the seed-to-sale tracking system
for distribution. If a sample encountered a detection above any action limit, it fails the primary round
of testing and may be eligible for a remediation pathway according to individual state regulations.
Results are often communicated to the licensee directly by email, and also by means of a laboratory
client portal where all historical product CoAs are available. Additionally, results must be reported
via the state database. The potency values issued on the CoA are used to label the product and serve as
the primary conduit for communication of product constituents to the consumer.