Why are Residual Solvents Dangerous?
Repeat exposure, often any exposure, to residual solvents can have carcinogenic and toxic effects to the body such as a loss of consciousness, headache, illness, or worse.

Chemical solvents (like butane, isopropyl alcohol, propane, or ethanol) are often used during the manufacturing process to improve yield, to affect the chemical properties of an ingredient or product, or to concentrate a material. Many of these solvents are detrimental to humans if consumed or inhaled, so it is imperative to make sure there are no residual solvents—even trace amounts—left behind after manufacturing. Heat, desiccation, vacuum, and other methods are required to remove solvents from a finished product, but the absence of residual solvents must be confirmed through testing.

Headspace-GC/MS (headspace gas chromatography mass spectrometry) is used to analyze any trace levels of solvents in various sample matrices.