Residual Solvent Testing

Highly concentrated oils and purified extracts are created through the use of Hydrocarbon gases and organic solvents. If the proper quality measurements are not taken the finished product will contain residue from the gasses or solvents that the consumer could ingest or inhale.

Testing Technologies can test for residual solvents in extracts, or edibles. To detect residual solvents we use GC-FID coupled with headspace analysis. We follow the residual solvents method USP 467. This method has been validated and is recommended by the United States Pharmacopoeia for testing of pharmaceuticals. In addition to our standard residual solvent panel we can test for any number of residual solvents.

WA I-502 Limits

Processors may use the hydrocarbons N-butane, isobutane, propane, or heptane or other solvents or gases exhibiting low to minimal potential human health-related toxicity approved by the board. These solvents must be of at least ninety-nine percent purity and a processor must use them in a professional grade closed loop extraction system designed to recover the solvents, work in an environment with proper ventilation, controlling all sources of ignition where a flammable atmosphere is or may be present.

It is required that solvent-based extracts using hydrocarbon gases undergo residual solvent testing. WAC Chapter 314-55-104, states: “the parts per million for one gram of finished extract cannot exceed 500 ppm of residual solvent or gas when quality assurance tested per RCW 69.50.348”

Extracts made from food grade ethanol, glycerin, propylene glycol, or CO2 of at least 99% purity do not require residual solvent testing.