How should the results of the Cannabis Typification or 4-AP field test be interpreted?

The results from the Cannabis Typification or 4-AP field test can be interpreted in one of four ways:

  • Blue color formation: Indicative of Marijuana (delta-9-THC concentration is greater than that of Cannabidiol).  The sample should be submitted to DFS for further analysis if criminal charges are to be pursued (excluding simple possession of marijuana cases that may only be submitted with a court order).
  • Pink color formation: Indicative of Hemp (Cannabidiol concentration is greater than that of delta-9-THC).  This sample should not be submitted to the lab for further testing unless the adjudication of the case hinges upon THC concentration determination down to 0.3% as defined in the Code of Virginia.  This method is currently being developed and validated by the Department.
  • Purple or dark blue color formation: Inconclusive result.  The test was likely conducted using too much plant material, and should be performed again using a fresh test kit and an appropriate amount of sample.  The appropriate amount of sample should be about the size of a grain of rice.
  • No color change: Inconclusive result.  Repeat the test again using a fresh test kit with an appropriate amount of sample.  The appropriate amount of sample should be about the size of a grain of rice.

For more information, please see the 4-AP informational page: https://dfs.virginia.gov/field-test-kits/4-ap-cannabis-typification-field-tests/