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IOWA DIVISION OF CRIMINAL INVESTIGATION
CRIMINALISTICS LABORATORY
DRUG IDENTIFICATION SECTION

Controlled Substance

This section identifies controlled substances in tablets, capsules, powders and plant materials submitted to the laboratory by law enforcement officers.

Plant material or extracts of plant material (photo1 and 2) which is suspected to be marijuana is examined under a low power microscope (photo 3). If certain botanical characteristics are seen, the material is subjected to two additional chemical tests (photos 4, 5 and 6). If all tests are positive, the plant material is identified as marijuana.

Powders are field-tested (a series of spot tests looking for functional groups)(photo 7 and photo 8). Based on the results, the samples are put on an appropriate thin-layer chromatography plate and compared to known drug samples (photo 9).

Often microcrystal tests are also done (photo 10 and photo 11).

Confirmation of a powder requires the use of a gas chromatograph/mass spectrometer or an infrared spectrophotometer.

This section typically receives 400-600 individual cases each month containing 1500 to 2000 items. The chart shown below gives the "top ten list" of drugs as identified in the controlled substance identification section of the crime lab.

Findings of the Controlled Substance Identification Section for the period beginning 01/01/2006 and ending 12/31/2006 (only top ten listed)

Substance Identified Number of Exams
1. Marijuana 7142
2. Methamphetamine 5089
3. Cocaine 3832
4. No Controlled Substance 1173
5. 3,4-methylenedioxymethamphetamine (MDMA) 144
6. Pseudoephedrine 119
7. Alprazolam 111
8. Hydrocodone 109
9. Oxycodone 102
10. Psilocybin 71
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Created: 02-07-2006
Last Updated: 11-17-2009 (JLR)