Maximum Yield Cannabis USA December 2017 / January 2018 | Page 47

N
ot long ago, I was at a cannabis
expo and a gentleman came
to our table to ask questions
about some symptoms he was
experiencing after using an oil
extract. He described a handful of
symptoms, including confusion, loss
of memory, headaches, and lack of
coordination. I suspected that the
product may have had residual
solvents that hadn’t been fully
removed during the processing.
Extract products have great benefits
for patients. Cannabinoids are present
in much higher concentrations, which
means less product is required for
a dose. Terpenes occur in higher
concentrations in extracts as well.
These high concentrations lend extracts
to further processing, like being
incorporated into edible products.
There are several ways to make
extracts from dry flowers, including
those that require large volumes
of solvents. These large quantities
improve the extraction efficiency
and obtain higher levels of purity.
Once the extraction is complete,
the solvents are removed from the
product. However, problems can arise
when this final stage is not executed
properly and not all the residual
solvents are removed. When chemical
solvents are not completely removed,
they can be present in high enough
concentrations to cause health
problems for the patient, especially
over time and with repeated
exposure. Also, if cheaper solvents
are used in place of high-quality
ones, unwanted contaminants can
create additional health risks.
Residual solvents can cause a wide
variety of non-specific and sometimes
irreversible health impacts to
individuals exposed to them. They can
cause eye, nose, and throat irritation,
and they can affect the central nervous
system, which can cause headaches,
dizziness, and light-headedness
progressing to unconsciousness,
seizures, and possible death. A number
of long-term adverse effects of solvents
have been carcinogenic.
Testing for the absence of
residual solvents is a critical step
in ensuring that we have safe
products for consumption.
myhydrolife.com
Residual solvents are classified
according to the health risk that they
pose. Any discussion that you find
about selecting residual solvents
for extractions always includes a
recommendation to use less toxic
solvents. Solvents do not add any
therapeutic benefit to the end-user,
and so should be removed from the
product before consumption. There
are three categories of solvents,
as described in Table 1: Classes of
Residual Solvents. Generally, the
residual solvents in Class 1 are so
toxic they should be avoided, always.
“
Producers can choose from
a number of processes for
extraction, including those that
use carbon dioxide or water and
those that are solvent-less.”
TABLE 1: CLASSES OF RESIDUAL SOLVENTS
CLASS ASSESSMENT
Class 1 Solvents to be avoided
Known human carcinogens
Strongly suspected human
carcinogens/Environmental hazards
Class 2
Solvents to be limited
Non-genotoxic animal carcinogens,
possible causative agents of
other irreversible toxicity, such as
neurotoxicity or teratogenicity
Solvents suspected of other
significant but reversible toxicities
Class 3
Solvents with low toxic potential
Solvents with low toxic potential to
humans; no health-based exposure
limit is needed
They are less toxic in acute or
short-term studies and negative in
genotoxicity studies
grow. heal. learn. enjoy.
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