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Understanding Chemical Grades

Chemical solvents play a critical role in the process of preparing cannabis and hemp for market and in the process of extracting essential oils and resins from the plant. It is important to be familiar with the grades and purity of solvents such as isopropyl alcohol, ethanol, pentane, hexane, heptane, and others that are commonly used in the production and processing of cannabis.

Individuals and businesses that process cannabis place trust in their suppliers to properly identify and label the chemical solvents they procure. It is important to know how to check the validity and accuracy of claims made by chemical suppliers in relation to the grade, purity of their products, and the suitability of the grade for the process.

Manufacturers and suppliers bear the responsibility to identify any applicable grade, regulatory, and chemical specifications for the chemical solvent being sold. Additionally, it is the supplier’s responsibility to provide safety and analysis documentation when applicable and as required by law.

It is imperative that everyone in the custody supply chain knows and understands the different grades of chemical solvents and their uses as explained below. It is also important to understand that the grade specifications are not necessarily hierarchical and that adherence to one grade specification does not imply adherence to any other specification. This means that high purity solvents may bear more than one grade to be thoroughly tested and documented for impurities.

The naming convention for grades for the unfamiliar consumer can often impart a false sense of purity or quality. Many in the industry are led to believe that a Laboratory Grade or Purified Grade is of a high purity standard because it sounds like a relatively high standard, when in reality, these solvents have a relatively low standard of specification for purity.

The purity of the chemical solvent used informs both the process and efficacy of the cannabis extraction as well as the impact on human health and safety. The info-graphic below lays out many of the most common grades and categorizes them by type as well as typical use cases.