1. Drug Identification

2. The challenge of forensic drug identification comes in selecting the correct procedure(s) that will ensure a specific identification of a drug 3 ways to identify drugs 1. PDR- Physician’s Desk Reference 2. Laboratory Tests- conclusive tests 3. Field Tests- presumptive tests

3. Controlled Substance Analysis Unknown Substance Plant? Confirmation Tests Micro Crystal GC/MS IR Microscopic Examination Macroscopic Examination Screening Tests Chemical Color Micro Crystal TLC GC/FID UV/Vis Chemical Exam Duquenois TLC GC/FID GC/MS No Yes

4. PDR Physician’s Desk Reference A quick and an easy identifier of manufactured pills, tablets, and capsules Updated each year Provides:  a picture of a drug,  whether it is a prescription, over the counter, or a controlled substance,  other detailed information about the drug

5. Presumptive Tests A presumptive test is an analysis of a sample which establishes either: The sample is definitely not a certain substance (“rule out”) Probable identification (“could be…”)

6. Presumptive Tests Pros  Quick, inexpensive, on the scene  Can be used for elimination purposes Cons  Cannot be used in court  Does not definitively identify a drug  Does not quantify amount

7. Presumptive Tests Include: 1. Spot or color tests 2. Microcrystalline test

8. Spot or Color Tests Use reagents that produce specific colors when reacting with certain classes of compounds  Chemically adding an auxochrome to drug molecule that shifts the optical absorption into the visible spectrum Need positive and negative controls to ensure reagents are reliable

9. Spot or Color Tests Colors are influenced by  Examiner’s subjectivity  Concentration of sample  Diluents  Adulterants (impure)  Age of reagent  Length of time reaction is observed

10. Spot or Color Tests Test NameIndicator for…Results in… MarquisMost opium derivatives (heroin, morphine) Purple AmphetaminesOrange-brown Dillie-KoppanylBarbituratesViolet-blue Duquenois- Levine MarijuanaPurple VanUrkLSDBlue-purple Scott testCocaineBlue

11. Color Tests Methamphetamine/ Marquis Reagent 2% formaldehyde in Sulfuric acid Methamphetamine/ Sodium Nitroprusside Heroin/ Marquis Reagent Heroin/ Mecke Reagent http://www.dps.state.ia.us/DCI/Crime_Lab/Controlled_Substance/cct.shtml#photo8

12. Color Test Kits Add suspected substance to the pouch. Seal Break ampoules in order Check for color change

13. Color Test Sequences Mayer’s Narcotics or Amphetamines White precip Barbituates No precip Marquis Dillye- Koppanyi Opiates purple Amphetamines Orange to red to brown Demerol brown Mescaline red Ecstasy black Nitric Acid Heroin yellow Morphine Red to orange to yellow Barbituates blue Mandelin’s Amphetamines Olive green confirms Methadone Dark blue http://www.bvda.com/EN/prdctinf/pf_en_np.html 16 different tests are available

14. Confirmatory Tests Can determine the exact identity of the substance Includes… Spectroscopy Ultraviolet (UV) Visible Infrared (IR) Screen solid samples for potential illicit substances Chromatography (liquid/gas) Microcrystalline Confirm that the illegal substance is present and to identify it Mass spectrometrySystematically quantified

15. Forensic Autopsy Look for  Irritated tissues  Characteristic odors  Mees line Single transverse white bands on nails Order toxicological screens to identify all the drugs and toxic compounds that are potentially present in a sample

16. Human Specimens for Analysis Blood Urine Vitreous humor of eye Bile Gastric contents Liver tissue Brain tissue Kidney tissue Hair Nails

17. Spectroscopy The interaction of electromagnetic radiation (light) with matter Measured using a spectrophotometer  An instrument used to measure and record the absorption spectrum (absorbed/reflected) of a chemical substance

18. Spectrophotometer

19. Thin Layer Chromatography Establishes the presence of specific cannabinoids Provides a color test Positive if patterns match those of a known reference run at the same time http://www.dps.state.ia.us/DCI/Crime_Lab/Controlled_Substance/add_tests.shtml

20. Thin Layer Chromatography The trick is getting the compounds out of the solid sample and on the plate Chemical Extractions  Physical extraction  Dry wash and dry extraction  Liquid/liquid extractions

21. Microcrystal Tests Sample is dissolved in solution Reagent is added generating a precipitate, which will have uniquely shaped crystals Must have a reference standard using same reagent Potential problems  Impurities can distort crystal shapes  High concentration leads to small crystals  Reagent age effects GHB “date-rape drug” Crystals following addition Of silver nitrate

22. Microcrystalline Tests http://www.dps.state.ia.us/DCI/Crime_Lab/images/blue42.jpg Cocaine Methamphetamine

23. Mass Spectrometry In a mass spectrometer, an electron beam is directed at sample molecules in a vacuum chamber The electrons break apart the sample molecules into many positively charged pieces that are sorted and collected according to their mass to charge ratio by a magnetic field Pattern that results is used to identify the sample

25. Field Tests Preliminary tests  Used to determine the degree of suspect’s physical impairment and whether or not another test is justified Psychophysical tests  3 basic tests exist Horizontal gaze nystagmus (HGN) Nine step walk and turn (WAT) One leg stand (OLS)

26. Field Tests Horizontal gaze nystagmus (HGN  Follow a pen or small flashlight, tracking left to right with one’s eyes  Wavering at 45 degrees indicates BAC of 0.10 Nine step walk and turn (WAT)  Comprehend and execute two or more simple instructions at a time One leg stand (OLS)  Maintain balance, comprehend and execute two or more simple instructions at one time

27. The Breathalyzer More practical in the field Collects and measures alcohol content of alveolar breath Breath sample mixes with 3 ml of 0.025% potassium dichromate in sulfuric acid and water  Measures light absorption of potassium dichromate before and after the reaction with alcohol

28. Duquesnois-Levine Test Test for presence of cannabinols, the active agent in marijuana Duquenois agent is 2% vanillin, 1% acetaldehyde in ethanol Purple color denotes a positive test http://www.dea.gov/photo_library4.html

29. Heavy Metals and Fertilizers Type of PoisonSymptom/Evidence Caustic poison (lye)Burns around the lips and mouth Carbon monoxideRed or pink patches on chest & thighs Sulfuric acidBlack vomit Hydrochloric acidGreenish-brown vomit Nitric acidYellow vomit PhosphorusCoffee brown vomit, onion or garlic odor CyanideBurnt almond odor Arsenic, mercuryPronounced diarrhea Methyl (wood) or isopropyl alcohol Nausea, vomiting, unconsciousness, blindness