1. 5-1 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein DRUGS Chapter 5 Agenda: Notes on Ch. 5 and Pre-lab

2. 5-2 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Introduction A drug can be defined as a natural or synthetic substance that is used to produce physiological or psychological effects in humans or other higher order animals. Narcotic drugs are analgesics, meaning they relieve pain by a depressing action on the central nervous system. This effects functions such as blood pressure, pulse rate and breathing rate.

3. 5-3 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Drug-Control Laws The U.S. federal law known as the Controlled Substances Act will serve to illustrate a legal drug-classification system created to prevent and control drug abuse. This federal law establishes five schedules of classification for controlled dangerous substances on the basis of a drug’s –potential for abuse –potential for physical and psychological dependence –medical value

4. 5-4 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein 4 Controlled Substances Act  Schedule I—high potential for abuse; no currently acceptable medical use in the US; a lack of accepted safety for use under medical supervision  Schedule II—high potential for abuse; a currently accepted medical use with severe restrictions; abuse may lead to severe psychological or physical dependence  Schedule III—lower potential for abuse than the drugs in I or II; a currently accepted medical use in the US; abuse may lead to moderate physical dependence or high psychological dependence  Schedule IV—low potential for abuse relative to drugs in III; a currently accepted medical use in the US; abuse may lead to limited physical or psychological dependence relative to drugs in III  Schedule V—low potential for abuse relative to drugs in IV; currently accepted medical use in the US; abuse may lead to limited physical or psychological dependence relative to drugs in IV

5. 5-5 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein 5 Examples of Controlled Substances and Their Schedule Placement  Schedule I—heroin (diacetylmorphine), LSD, marijuana, ecstasy (MDMA)  Schedule II—cocaine, morphine, amphetamines (including methamphetamines), PCP, Ritalin  Schedule III—intermediate acting barbiturates, anabolic steroids, ketamine  Schedule IV—other stimulants and depressants including Valium, Xanan, Librium, phenobarbital, Darvon  Schedule V—codeine found in low doses in cough medicines

6. 5-6 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein 6 Human Components Used for Drug Analysis  Blood  Urine  Hair  Gastric Contents  Bile  Liver tissue  Brain tissue  Kidney tissue  Spleen tissue  Vitreous Humor of the Eye

7. 5-7 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Drug Identification The challenge or difficulty of forensic drug identification comes in selecting analytical procedures that will ensure a specific identification of a drug. This plan, or scheme of analysis, is divided into two phases. –Screening test that is nonspecific and preliminary in nature to reduce the possibilities to a manageable number. –Confirmation test that is a single test that specifically identifies a substance.

8. 5-8 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein 8 Drug Identification Screening or presumptive tests  Spot or color tests  Microcrystalline test Confirmatory tests  Spectrophotometry  Ultraviolet (UV)  Visible  Infrared (IR)  Mass spectrometry

9. 5-9 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Preliminary Analysis Faced with the prospect that the unknown substance may be any one of a thousand or more commonly encountered drugs, the analyst must employ screening tests to reduce these possibilities to a small and manageable number. This objective is often accomplished by subjecting the material to a series of color tests that will produce characteristic colors for the more commonly encountered illicit drugs.

10. 5-10 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein 10 Presumptive Color Tests  Marquis—turns purple in the presence of most opium derivatives and orange-brown with amphetamines  Dillie-Koppanyi—turns violet- blue in the presence of barbiturates  Duquenois-Levine—turns a purple color in the presence of marijuana  Van Urk—turns a blue-purple in the presence of LSD  Scott test—color test for cocaine, blue

11. 5-11 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Preliminary Analysis Microcrystalline tests can also be used to identify specific drug substances by studying the size and shape of crystals formed when the drug is mixed with specific reagents.

12. 5-12 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Confirmational Determination Once this preliminary analysis is completed, a confirmational determination is pursued. Forensic chemists will employ a specific test to identify a drug substance to the exclusion of all other known chemical substances. Typically infrared spectrophotometry or gas chromatography-mass spectrometry is used to specifically identify a drug substance.

13. 5-13 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Qualitative vs. Quantitative Another consideration in selecting an analytical technique is the need for either a qualitative or a quantitative determination. The former relates just to the identity of the material, whereas the latter requires the determination of the percent composition of the components of a mixture.

14. 5-14 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Chromatography Chromatography is a means of separating and tentatively identifying the components of a mixture.

15. 5-15 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Chromatography The theory of chromatography is based on the observation that chemical substances have a tendency to partially escape into the surrounding environment when dissolved in a liquid or when absorbed on a solid surface. Those materials that have a preference for the moving phase will slowly pull ahead and separate from those substances that prefer to remain in the stationary phase.

16. 5-16 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Gas Chromatography The stationary phase is a thin film of liquid contained within the column. After a mixture has traversed the length of the column, it will emerge separated into its components.

17. 5-17 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein UVand IR Spectrophotometry Currently, most forensic laboratories use UV and IR spectrophotometers to characterize chemical compounds. The simplicity of the UV spectrum facilitates its use as a tool for determining a material’s probable identity, although it may not provide a definitive result. The IR spectrum provides a far more complex pattern.

18. 5-18 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein UVand IR Spectrophotometry Different materials always have distinctively different infrared spectra; each IR spectrum is therefore equivalent to a “fingerprint” of that substance.

19. 5-19 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Mass Spectrometry In the mass spectrometer, a beam of high-energy electrons collide with a material, producing positively charged ions.

20. 5-20 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Mass Spectrometry These positive ions almost instantaneously decompose into numerous fragments, which are separated according to their masses. The unique feature of mass spectrometry is that under carefully controlled conditions, no two substances produce the same fragmentation pattern.

21. 5-21 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein GC and Mass A direct connection between the GC column and the mass spectrometer allows each component to flow into the mass spectrometer as it emerges from the GC.

22. 5-22 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein GC and Mass The separation of a mixture’s components is first accomplished by the GC. Then, fragmentation of each component by high-energy electrons in the mass spectrometer, will produce a distinct pattern, somewhat like a “fingerprint”, of the substance being examined.

23. 5-23 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein GC and Mass

24. 5-24 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Collection and Preservation The field investigator has the responsibility of ensuring that the evidence is properly packaged and labeled for the laboratory. Generally common sense is the best guide, keeping in mind that the package must prevent the loss of the contents and/or cross- contamination.

25. 5-25 ©2011, 2008 Pearson Education, Inc. Upper Saddle River, NJ 07458 FORENSIC SCIENCE: An Introduction, 2 nd ed. By Richard Saferstein Collection and Preservation Often the original container in which the drug was seized will suffice. All packages must be marked with information that is sufficient to ensure identification by the officer in the future and establish the chain of custody.