Residual solvents refer to the solvents left behind after the extraction process. Various types of solvents are used to extract desired cannabis compounds, such as cannabinoids and terpenes, from plant material to make cannabis concentrates. In some cases, impurities from the solvent can remain in the extracted material, and they can be toxic.

Residual solvent testing is a critical element of testing cannabis before it reaches the final consumer. Residual solvent testing is required for many products, such as concentrates, waxes, oils, shatters, and other cannabis products. Various chemical solvents are used to produce cannabis concentrate products, and most of them are harmful when inhaled.

Residual solvents associated with the extraction process include Butane, Acetone, Isopropanol, Heptane, Propane, and Hexane. Repeated exposure to residual solvents and cause headaches, nausea, allergic reactions, and even life-threatening illnesses. Exposure to Butane, for example, can cause liver damage, kidney failure, break down the nervous system, and/or lead to respiratory failure. Exposure to Acetone can cause dizziness, vomiting, confusion, or unconsciousness.