Pesticide Testing
The detection of pesticides in cannabis has been a challenge. There are many pesticides that are used in commercial cannabis grow operations to kill the pests that thrive on the plants and in greenhouses. These chemicals are toxic to humans so confirming their absence from cannabis products is crucial. A majority of states require labs to test for an average of 18 different pesticides.
SCIENTIFIC METHODS
Testing for pesticides is one of the more problematic analyses, resulting in the need for two different instruments. For a majority of pesticides, liquid chromatography mass spectrometry (LCMS) is acceptable and operates much like HPLC, but utilizes a different detector and sample preparation. Pesticides that do not ionize well in an LCMS source require the use of a gas chromatography-mass spectrometry (GCMS) instrument. The principles of HLPC still apply – you inject a sample, separate it on a column, and detect with some detector. However, in this case, a gas (typically helium) is used to carry the sample.