Solvent Residue Analysis

Ensure Patients Are Not Exposed to Unsafe Levels of Solvents

Solvent Residue Analysis

Patients are increasingly opting for potent cannabis concentrates like butter, hash oil, shatter, and wax. To make these products, cannabinoids and terpenoids are often isolated from the cannabis plant using a solvent-based extraction process.

Solvents are then eliminated from the concentrate using heat, pressure, or other methods. This removal process is critical as all these solvents pose health risks to patients.

Solvents Pose a Significant Health Hazard

Exposure to unsafe levels of solvents can be very dangerous to patients. Solvents have been linked to higher incidents of:

  • Cancer
  • Dermatitis
  • Liver and kidney damage
  • Reproductive damage
  • Respiratory impairment
  • Toxicity to the nervous system

Our Testing Process

We use a Headspace Gas Chromatography (GC-MS) process to quantify up to 10 parts-per-million (ppm) residual solvents commonly used to extract cannabinoids from concentrates, such as:

  • Acetone
  • Butane
  • Ethanol
  • Hexane
  • Isobutane
  • Isopentane
  • Isopropanol
  • Naphtha
  • Pentane
  • Propane

Cannabinoid Extraction Methods

Dry Sieve

This is a  natural method of extracting compounds by sifting trim and shake through a fine-weave screen filter. This solvent-free process does not always produce the cleanest or most effective results.


This method uses ice, screens of different micron sizes, and agitation to remove trichomes. While slightly more effective than dry sieve, there is a danger of mold growth if the extract is not dried thoroughly.

Carbon Dioxide

This is a very effective, although expensive, extraction method that does not use solvents and creates a clean and pure product.

Isopropyl Alcohol

Due to the ability to dissolve waxes, Isopropyl alcohol is best used as a quick wash to increase the purity of the cannabis extract.


The two-wash Quick Wash Ethanol, or QWET, process is probably the most common and easily executed extraction process. The first wash can extract 75 to 80% of the oil, the second extracts most of the balance.


When performed safely in a laboratory, butane and propane extractions are inexpensive and create clean, potent products. Either solvent is easily purged.


Although an effective solvent, hexane is more toxic than butane, and is insoluble in water, extremely flammable, and potentially explosive.

Solving Solvent Problems

There are many methods to extract cannabinoids from the cannabis plant, but regardless of which method you choose, it is crucial to remove all solvents used in the extraction process.

For added safety, you can remove residual solvents by drying the extract. This typically four-day process can be reduced by gently warming the extract.