Chapter 11 - Drugs

Analgesic

"A substance that lessens or eliminates pain." Heroin and other narcotic drugs are analgesics—that is, they relieve pain by depressing the central nervous system. Besides being a powerful analgesic, heroin produces a "high" that is accompanied by drowsiness and a deep sense of well-being. The effect is short, generally lasting only three to four hours. Regular use of heroin—or any other narcotic drug—invariably leads to physical dependence, with all its dire consequences.

Microcrystalline Tests

"A test that identifies a specific substance based on the color and shape of crystals formed when the substance is mixed with specific reagents." A technique considerably more specific than color tests is the microcrystalline test. A drop of a chemical reagent is added to a small quantity of the drug on a microscopic slide. After a short time, a chemical reaction ensues, producing a crystalline precipitate. The size and shape of the crystals, examined under a compound microscope, reveal the identity of the drug. Over the years, analysts have developed hundreds of crystal tests to characterize the most commonly used drugs. These tests can be rapidly executed and often do not require the isolation of a drug from its diluents; however, because diluents can sometimes alter or modify the shape of the crystal, the examiner must develop experience in interpreting the results of the test.

Spectrophotometry

"An analytical method for identifying a substance by its selective absorption of different wavelengths of light." The technique of chromatography is particularly suited for analyzing illicit drugs because it can separate a drug from other substances that may be present in the drug preparation. However, chromatography has the drawback of not being able to specifically identify the material under investigation. For this reason, other analytical tools are frequently used to identify drugs. These include the technique of spectrophotometry, which can identify a substance by exposing it to a specific type of electromagnetic radiation.

Chromatography

"Any of several analytical techniques for separating organic mixtures into their components by attraction to a stationary phase while being propelled by a moving phase." Chromatography is a means of separating and tentatively identifying the components of a mixture. It is particularly useful for analyzing drug specimens, which may be diluted with practically any material to increase the quantity of the product available to prospective customers. The task of identifying an illicit-drug preparation would be arduous without the aid of chromatographic methods to first separate the mixture into its components.

Five primary color-test reagents are as follows:

1) Marquis. The reagent turns purple in the presence of heroin and morphine and most opium derivatives. Marquis becomes orange-brown when mixed with amphetamines and methamphetamines. 2) Dillie-Koppanyi. This is a valuable screening test for barbiturates, in whose presence the reagent turns a violet-blue color. 3) Duquenois-Levine. This is a valuable color test for marijuana, performed by adding a series of chemical solutions to the suspect vegetation. A positive result is shown by a purple color when chloroform is added. 4) Van Urk. The reagent turns blue-purple in the presence of LSD. However, owing to the extremely small quantities of LSD in illicit preparations, this test is difficult to conduct under field conditions. 5) Scott Test. This is a color test for cocaine. A powder containing cocaine turns a cobalt thiocyanate solution blue. Upon the addition of hydrochloric acid, the blue color is transformed to a clear pink color. Upon the addition of chloroform, if cocaine is present, the blue color reappears in the chloroform layer.

Drug evidence must be properly packaged before it is sent to the lab. Which is/are acceptable way(s) to package drug evidence?

1) Package loose drugs in a plastic sealable bag or in a druggist's fold and a manila envelope. 2) Volatile solvents involved in glue-sniffing cases should be packaged in airtight containers. 3) Leave it in the container in which it was found (provided there are no breaches in the packaging). 4) All of the above Answer: All of these are acceptable ways to package drug evidence.

CHAPTER 11 REVIEW

11.1 Explain psychological and physical dependency on drugs, and its impact on the society - A drug is a natural or synthetic substance that is used to produce physiological or psychological effects in humans or other animals. - Nondrug factors that play a part in drug dependence include the personal characteristics of the user, the user's expectations about the drug experience, society's attitudes toward and possible responses to the drug, and the setting in which the drug is used. - Physical dependence is defined as a physiological need for a drug that has been brought about by its regular use. Psychological dependence is the conditioned use of a drug caused by underlying emotional needs. 11.2 Classify the commonly used drugs - Narcotic drugs are analgesics, meaning that they relieve pain by depressing the central nervous system. - The most common source for narcotic drugs is opium. Morphine is extracted from opium and used to synthesize heroin. - Opiates are not derived from opium or morphine, but they have the same physiological effects on the body. Examples of opiates are methadone and OxyContin (i.e., oxycodone). - Hallucinogens cause marked changes in normal thought processes, perceptions, and moods. Marijuana is the most well-known drug in this class. Other hallucinogens include LSD, mescaline, PCP, psilocybin, and MDMA (or Ecstasy). - Depressants decrease the activity of the central nervous system, calm irritability and excitability, and produce sleep. Depressants include alcohol (i.e., ethanol), barbiturates, tranquilizers, and various substances that can be sniffed such as airplane glue and model cement. - Stimulants increase the activity of the central nervous system and are taken to increase alertness and activity. Stimulants include amphetamines, sometimes known as "uppers" or "speed," and cocaine, which in its freebase form is known as "crack." - Club drugs are synthetic drugs that are used at nightclubs, bars, and raves (i.e., all-night dance parties). Some club drugs act as stimulants; others have depressant effects. - Anabolic steroids are synthetic compounds that are chemically related to the male sex hormone testosterone. Anabolic steroids are often used by individuals who are interested in accelerating muscle growth. 11.3 Explain the classification of drugs under the Controlled Substances Act - Federal law establishes five schedules of classification for controlled dangerous substances on the basis of a drug's potential for use, potential for physical and psychological dependence, and medical value. 11.4 Understand the proper collection and preservation of drug evidence - The packaging of drug evidence must prevent loss and/or cross-contamination of the contents, and often the original container in which the drug was seized is used. Specimens suspected of containing volatile solvents must be packaged in an airtight container to prevent evaporation. - The investigator may help in the identification of the drug by supplying to the drug analyst any background information that may relate to the drug's identity. 11.5 Describe the laboratory tests used to perform drug identification analysis - Analysts use screening tests to determine the identity of drugs present in a sample. These tests reduce the number of possible drugs to a small and manageable number. - A series of color tests produce characteristic colors for the more commonly encountered illicit drugs. In a microcrystalline test, a drop of a chemical reagent added to a small quantity of drug on a microscope slide produces crystals highly characteristic of a drug. - After preliminary testing, forensic chemists use more specific tests to identify a drug substance to the exclusion of all other known chemical substances. - Chromatography is a means of separating and tentatively identifying the components of a mixture. - Thin-layer chromatography (TLC) uses a solid stationary phase, usually coated onto a glass plate, and a mobile liquid phase to separate the components of the mixture. - Gas chromatography (GC) separates mixtures on the basis of their distribution between a stationary liquid phase and a mobile gas phase. - Spectrophotometry is the measurement of the absorption of light by chemical substances. - Dispersion is the process of separating light into its component colors. Each component bends, or refracts, at a different angle as it emerges from the prism. The large family of radiation waves is known as the electromagnetic spectrum. - Most forensic laboratories use ultraviolet (UV) and infrared (IR) spectrophotometers to characterize chemical compounds. - IR spectrophotometry provides a far more complex pattern than UV spectrophotometry. Because different materials have distinctively different infrared spectra, each IR spectrum is equivalent to a "fingerprint" of that substance. - Mass spectrometry characterizes organic molecules by observing their fragmentation pattern after their collision with a beam of high-energy electrons. - Infrared spectrophotometry and mass spectrophotometry typically are used to identify a specific drug substance.

Types of Drugs

11.2 Classify the commonly abused drugs.

Drug Control Laws

11.3 Explain the classification of drugs under the Controlled Substances Act.

QUICK REVIEW 11.1

A drug is a natural or synthetic substance that is used to produce physiological or psychological effects in humans or other animals. Nondrug factors that play a part in drug dependence include the personal characteristics of the user, the user's expectations about the drug experience, society's attitudes toward and possible responses to the drug, and the setting in which the drug is used. Physical dependence is defined as a physiological need for a drug that has been brought about by its regular use. Psychological dependence is the conditioned use of a drug caused by underlying emotional needs.

Synthetic Opiates

A number of narcotic drugs are not naturally derived from opium. However, because they have physiological effects on the body that are similar to the opium narcotics, they are also commonly referred to as "opiates." Methadone is perhaps the best-known synthetic opiate. In the 1960s, scientists discovered that a person who received periodic doses of methadone would not get high if they then took heroin or morphine. Although methadone is pharmacologically related to heroin, its administration appears to eliminate the user's desire for heroin, with minimal side effects. These discoveries led to the establishment of controversial methadone maintenance programs in which heroin users receive methadone to reduce or prevent future heroin use. Physicians increasingly prescribe methadone for pain relief. Unfortunately, the wide availability of methadone for legitimate medical purposes has recently led to greater quantities of the drug being diverted into the illicit market.

Crack

A particularly potent form of cocaine known as "crack" can be produced by mixing cocaine with baking soda and water and then heating the resulting solution. This material is then dried and broken into tiny chunks that dealers sell as crack "rocks" that are sufficiently volatile to be smoked. The faster the cocaine level rises in the brain, the greater the euphoria, and the fastest way to attain a rise in the brain's cocaine level is to smoke crack. Inhaling the cocaine vapor delivers the drug to the brain in less than fifteen seconds—about as fast as injecting it and much faster than snorting it. The dark side of crack, however, is that the euphoria fades quickly as the cocaine levels rapidly drop, leaving the user feeling depressed, anxious, and pleasureless. The desire to return to the euphoric feeling is so intense that crack users quickly develop a habit for the drug that is almost impossible to overcome. Only a small percentage of crack users are ever cured of this drug habit. When a person uses large amounts of crack cocaine numerous times, they usually develops a sense of paranoia. Paranoid delusions cause the person to lose their sense of reality, leaving them trapped in a world full of voices, whispers, and suspicions. Sufferers come to believe that they are being followed and that their drug use is being watched. In the United States, cocaine use is on the rise. Many people are using cocaine apparently to improve their ability to work and to keep going when tired. Although there is no evidence of physical dependency accompanying cocaine's repeated use, abstention from cocaine after prolonged use brings on severe bouts of mental depression that produce a very strong compulsion to resume using the drug. In fact, laboratory experiments with animals have demonstrated that, of all the commonly used drugs, cocaine produces the strongest psychological compulsions for continued use. The United States spends millions of dollars annually in attempting to control cultivation of the coca leaf in various South American countries and to prevent the trafficking of cocaine into the United States. Three-quarters of the cocaine smuggled into the United States was refined in clandestine laboratories in Colombia. The profits are astronomical. Peruvian farmers may be paid $200 for enough coca leaves to make one pound of cocaine. The refined cocaine is worth $1,000 when it leaves Colombia and sells at retail in the United States for up to $20,000.

Closer Analysis The Gas Chromatograph

A simplified scheme of the gas chromatograph is shown in the figure. The operation of the instrument can be summed up briefly as follows: The carrier gas is fed into the column at a constant rate. The carrier gas, generally nitrogen or helium, is chemically inert. The sample under investigation is injected as a liquid into a heated injection port with a syringe, where it is immediately vaporized and swept into the column by the carrier gas. The column itself is heated in an oven in order to keep the sample in a vapor state as it travels through the column. In the column, the components of the sample travel in the direction of the carrier gas flow at speeds that are determined by their distribution between the stationary and moving phases. If the analyst has selected the proper liquid phase and has made the column long enough, the components of the sample will be completely separated as they emerge from the column. As each component emerges from the column, it enters a detector. One type of detector uses a flame to ionize the emerging chemical substance, thus generating an electrical signal. The signal is recorded on a strip-chart recorder as a function of time. This written record of the separation is called a "chromatogram." A gas chromatogram is a plot of the recorder response (on the vertical axis) over time (on the horizontal axis). A typical chromatogram shows a series of peaks, each of which corresponds to one component of the mixture. Basic gas chromatography. Gas chromatography permits rapid separation of complex mixtures into individual compounds and allows identification and quantitative determination of each compound. As shown, a sample is introduced by a syringe (1) into a heated injection chamber (2). A constant stream of nitrogen gas (3) flows through the injector, carrying the sample into the column (4), which contains a thin film of liquid. The sample is separated in the column, and the carrier gas and separated components emerge from the column and enter the detector (5). Signals developed by the detector activate the recorder (7), which makes a permanent record of the separation by tracing a series of peaks on the chromatograph (8). The time it takes a component to emerge from the column identifies the component present, and the peak area identifies the concentration.

Other Hallucinogens

A substantial number of other substances with widely varying chemical compositions are also used recreationally because of their hallucinogenic properties. These include both naturally occurring substances such as mescaline and psilocybin and synthetically created drugs including lysergic acid diethylamide (LSD) and phencyclidine (PCP). LSD is synthesized from lysergic acid, a substance derived from ergot, which is a type of fungus that attacks certain grasses and grains. The drug appears in a variety of forms—as a pill, added to a cube of sugar, or absorbed onto a small piece of paper—and is taken orally. Its hallucinogenic effects were first described by the Swiss chemist Albert Hofmann after he accidentally ingested some of the material in his laboratory in 1943. LSD produces marked changes in mood, leading to laughing or crying at the slightest provocation. Feelings of anxiety and tension almost always accompany LSD use. LSD is very potent; as little as twenty-five micrograms is enough to induce vivid visual hallucinations that can last for about twelve hours. Although physical dependence does not develop with continued use, the individual user may be prone to flashbacks and psychotic reactions even after use is discontinued.

Figure 11-14-15 An example of the chromatographic separation of ink is shown

A) a Very thin coating of silica gel or aluminum oxide - Put sample spot B) Rising solvent; original spot has separated into several spots "(b) (a) In thin-layer chromatography, a liquid sample is spotted onto the granular surface of a gel-coated plate. (b) The plate is placed into a closed chamber that contains a liquid. As the liquid rises up the plate, the components of the sample distribute themselves between the coating and the moving liquid. The mixture is separated, with substances with a greater affinity for the moving liquid traveling up the plate at a faster speed." "(c) (a) In thin-layer chromatography, the liquid phase begins to move up the stationary phase.(b) Liquid moves past the ink spot carrying the ink components up the stationary phase.(c) The moving liquid has separated the ink into its several components."

Which of the following drugs is said to have a high risk for psychological dependence?

Alcohol As a depressant, alcohol has a high risk for both psychological and physical dependence.

Antipsychotic and Antianxiety Drugs

Although antipsychotic and antianxiety drugs can be considered depressants, they differ from barbiturates in the extent of their effects on the central nervous system. Generally, these drugs produce a relaxing tranquility without impairing high-thinking faculties or inducing sleep. Antipsychotics, such as reserpine and chlorpromazine, have been used to reduce the anxieties and tension of people diagnosed with anxiety disorders. A group of antianxiety drugs are commonly prescribed to deal with the everyday tensions of many healthy people. These drugs include meprobamate (Miltown), chlordiazepoxide (Librium), diazepam (Valium), and Xanax. In the past forty-five years, the use of these drugs—particularly antianxiety drugs—has grown dramatically. Medical evidence shows that these drugs produce psychological and physical dependence with repeated and high levels of usage. For this reason, the widespread prescribing of antianxiety drugs to overcome the pressures and tensions of life has worried many people who fear a legalized drug culture is being created.

Name 3 Stimulants

Amphetamine Cocaine Methamphetamine

Amphetamines

Amphetamines are a group of synthetic stimulants that share a similar chemical structure and are commonly referred to in the terminology of the drug culture as "uppers" or "speed." They are typically taken either orally or via intravenous injection and provide a feeling of well-being and increased alertness that is followed by a decrease in fatigue and a loss of appetite. However, these apparent benefits of the drug are accompanied by restlessness and instability or apprehensiveness, and once the stimulant effect wears off, depression may set in. In the United States, the most serious form of amphetamine use stems from intravenous injection of amphetamine or its chemical derivative, methamphetamine (see Figure 11-8). The desire for a more intense amphetamine experience is the primary motive for this route of administration. The initial sensation of a "flash" or "rush," followed by an intense feeling of pleasure, constitutes the principal appeal of the intravenous route for the user. During a "speed binge," the individual may inject amphetamines every two to three hours. Users have reported experiencing a euphoria that produces hyperactivity, with a feeling of clarity of vision as well as hallucinations. As the effect of the amphetamines wears off, the individual lapses into a period of exhaustion and may sleep continuously for one or two days. Following this, the user often experiences a prolonged period of severe depression lasting from days to weeks. A smokable form of methamphetamine, known as "ice," is reportedly in heavy demand in some areas of the United States. Ice is prepared by slowly evaporating a methamphetamine solution to produce large, crystal-clear "rocks." Like crack cocaine (discussed next), ice is smoked and produces effects similar to those of crack cocaine, but the effects last longer. Once the effects of ice wear off, users often become depressed and may sleep for days. Chronic users exhibit violent destructive behavior and acute psychosis similar to paranoid schizophrenia. Repeated use of amphetamines leads to a strong psychological dependence, which encourages their continued use.

The Spectrophotometer

An object does not absorb all the visible light it is exposed to; instead, it selectively absorbs some frequencies and reflects or transmits others. Similarly, the absorption of other types of electromagnetic radiation by chemical substances is also selective. Selective absorption of a substance is measured by an instrument called a "spectrophotometer," which produces a graph or "absorption spectrum" that depicts the absorption of light as a function of wavelength or frequency. The spectrophotometer measures and records the absorption spectrum of a chemical. The basic components of a simple spectrophotometer are the same regardless of whether it is designed to measure the absorption of UV, visible, or IR radiation. These components are illustrated diagrammatically in Figure 11-21. They include (1) a radiation source, (2) a monochromator or frequency selector, (3) a sample holder, (4) a detector to convert electromagnetic radiation into an electrical signal, and (5) a recorder to produce a record of the signal. The measuring absorption of UV, visible, and IR radiation is particularly applicable to obtaining qualitative data pertaining to the identification of drugs.

Anabolic Steroids (Testosterone)

Anabolic steroids are synthetic compounds that are chemically related to the male sex hormone testosterone. "Synthetic compounds, chemically related to the male sex hormone testosterone, that is used to promote muscle growth." Testosterone has two effects on the body. It promotes the development of secondary male characteristics (i.e., androgenic effects), and it accelerates muscle growth (i.e., anabolic effects). Efforts to promote muscle growth and to minimize the hormone's androgenic effects have led to the synthesis of numerous anabolic steroids. However, a steroid free of the accompanying harmful side effects of an androgen drug has not yet been developed. Testosterone has two effects on the body. It promotes the development of secondary male characteristics (i.e., androgenic effects), and it accelerates muscle growth (i.e., anabolic effects). Incidence of steroid use first received widespread public attention when both amateur and professional athletes were discovered using these substances to enhance their performance. Interestingly, current research on male athletes given anabolic steroids has generally found little or, at best, marginal evidence of enhanced strength or performance. Although the full extent of anabolic steroid use by the general public is not fully known, the U.S. government is sufficiently concerned to regulate the availability of these drugs to the general population and to severely punish individuals for illegal possession and distribution of anabolic steroids. In 1991, anabolic steroids were classified as controlled dangerous substances, and the Drug Enforcement Administration was given enforcement power to prevent their illegal use and distribution Anabolic steroids are usually taken by individuals who are unfamiliar with their harmful medical side effects. Liver cancer and other liver malfunctions have been linked to steroid use. These drugs also cause masculinizing effects in females, infertility, and diminished sex drive in males. For teenagers, anabolic steroids result in the premature halting of bone growth. Anabolic steroids can also cause unpredictable effects on mood and personality, leading to unprovoked acts of anger and destructive behavior. Depression is also a frequent side effect of anabolic steroid use.

Quick Review

Analysts use screening tests to determine the identity of drugs present in a sample. These tests reduce the number of possible drugs to a small and manageable number. A series of color tests produce characteristic colors for the more commonly encountered illicit drugs. In a microcrystalline test, a drop of a chemical reagent added to a small quantity of drug on a microscope slide produces crystals highly characteristic of a drug. After preliminary testing, forensic chemists use more specific tests to identify a drug substance to the exclusion of all other known chemical substances.

Qualitative or a Quantitative determination

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 refers to the percentage of each component in the mixture. Hence, a qualitative identification of a powder may reveal the presence of heroin and quinine, whereas a quantitative analysis may conclude the presence of 10 percent heroin and 90 percent quinine. Obviously, a qualitative identification must precede any attempt at quantitation; there is little value in attempting to quantitate a material without first determining its identity. Essentially, a qualitative analysis of a material requires the determination of numerous properties using a variety of analytical techniques. On the other hand, a quantitative measurement is usually accomplished by precise measurement of a single property of the material.

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Barbiturates

Barbiturates are commonly referred to as "downers" because they relax, create a feeling of well-being, and produce sleep. Like alcohol, barbiturates suppress the vital functions of the central nervous system. Collectively, barbiturates can be described as derivatives of barbituric acid, which was first synthesized by a German chemist, Adolf von Bayer, more than a hundred years ago. Twenty-five barbiturate derivatives are currently used in medical practice in the United States; however, five—amobarbital, secobarbital, phenobarbital, pentobarbital, and butabarbital—tend to be used for most medical applications. Slang terms for "barbs" usually stem from the color of the capsule or tablet (e.g., "yellow jackets," "blue devils," and "reds"). Normally, barbiturate users take these drugs orally. The average sedative dose is about ten to seventy milligrams. When taken in this fashion, the drug enters the blood through the walls of the small intestine. Some barbiturates, such as phenobarbital, are classified as long-acting barbiturates. They are absorbed into the bloodstream more slowly than others and therefore produce less pronounced effects than faster-acting barbiturates. The slow action of phenobarbital accounts for its low incidence of use. Apparently, barbiturate users prefer the faster-acting varieties: secobarbital, pentobarbital, and amobarbital. In the early 1970s, a nonbarbiturate depressant, methaqualone (brand name Quaalude), appeared on the illicit-drug scene. Methaqualone is a powerful sedative and muscle relaxant that possesses many of the depressant properties of barbiturates. When taken in prescribed amounts, barbiturates are relatively safe, but in instances of extensive and prolonged use, physical dependence can develop.

Cocaine

Between 1884 and 1887, pioneering psychologist Sigmund Freud created something of a sensation in European medical circles by describing his experiments with a new drug. He reported a substance of seemingly limitless potential as a source of "exhilaration and lasting euphoria" that permitted "intensive mental or physical work [to be] performed without fatigue." He wrote, "It is as though the need for food and sleep was completely banished." The object of Freud's enthusiasm was cocaine, a stimulant extracted from the leaves of Erythroxylon coca, a plant grown in the Andes mountains of South America as well as in tropical Asia (see Figure 11-9). Most commonly, cocaine is sniffed or "snorted" and absorbed into the body through the mucous membranes of the nose, but it is sometimes injected. Cocaine is a powerful stimulant to the central nervous system, and its effects resemble those caused by amphetamines—namely, increased alertness and vigor accompanied by suppression of hunger, fatigue, and boredom. Cocaine produces a feeling of euphoria by stimulating a pleasure center in the base of the brain, in an area connected to nerves that are responsible for emotions. It stimulates this pleasure center to a far greater degree than it would ever normally be stimulated. Some regular users of cocaine report accompanying feelings of restlessness, irritability, and anxiety. Cocaine used chronically or at high doses can have toxic effects. Cocaine-related deaths result from cardiac arrest or seizures followed by respiratory arrest.

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11.5 QUICK REVIEW

Chromatography is a means of separating and tentatively identifying the components of a mixture. Thin-layer chromatography (TLC) uses a solid stationary phase, usually coated onto a glass plate, and a mobile liquid phase to separate the components of the mixture. Gas chromatography (GC) separates mixtures on the basis of their distribution between a stationary liquid phase and a mobile gas phase. Spectrophotometry is the measurement of the absorption of light by chemical substances. Dispersion is the process of separating light into its component colors. Each component bends, or refracts, at a different angle as it emerges from the prism. The large family of radiation waves is known as the "electromagnetic spectrum." Most forensic laboratories use ultraviolet (UV) and infrared (IR) spectrophotometers to characterize chemical compounds. IR spectrophotometry provides a far more complex pattern than UV spectrophotometry. Because different materials have distinctively different infrared spectra, each IR spectrum is equivalent to a "fingerprint" of that substance. Mass spectrometry characterizes organic molecules by observing their fragmentation pattern after their collision with a beam of high-energy electrons. Infrared spectrophotometry and mass spectrophotometry typically are used to identify a specific drug substance.

Which type of drug includes substances such as GHB and Ecstasy?

Club drugs These are synthetic substances often used by party goers to enhance their rave or club experience, and a significant amount of usage has been found among teens and young adults.

Which of the following drugs is said to have a high risk for psychological dependence but a low risk for physical dependence?

Cocaine Cocaine usage is a heavily involved action, often resulting in psychological dependence but not physical dependence.

Which of the following narcotics is said to have a low psychological dependence risk?

Codeine This drug is often used in medical practice, and while it has a low risk for psychological dependence, it has a high risk of physical dependence

Depressants

Depressants are drugs that slow down, or depress, the central nervous system. Several types of drugs fall into this category, including the most widely used drug in the United States: alcohol.

Following are descriptions of behavior that are characteristic among users of certain classes of drugs. Match each description with the drug that produces the described effects.

Depressants: - Slurred speech, slow reaction time, impaired judgment, reduced coordination. Hallucinogens: - Intense emotional response, anxiety, altered sensory perceptions Stimulants: - Alertness, feelings of strength and confidence, rapid speech and movement, decreased appetite. Narcotics: - Drowsiness, intense feeling of well-being, relief from pain.

11.5 Forensic Drug Analysis

Describe the laboratory tests used to perform drug identification analysis.

1.1 Drug Dependence

Explain psychological and physical dependency on drugs, and its impact on the society.

QUICK REVIEW 11.4

Federal law establishes five schedules of classification for controlled dangerous substances on the basis of a drug's potential for use, the potential for physical and psychological dependence, and medical value. The packaging of drug evidence must prevent loss and/or cross-contamination of the contents, and often the original container in which the drug was seized is used. Specimens suspected of containing volatile solvents must be packaged in an airtight container to prevent evaporation. The investigator may help in the identification of the drug by supplying the drug analyst with any background information that may relate to the drug's identity.

Nondrug factors

Furthermore, nondrug factors play an equally crucial role in determining the behavioral patterns associated with drug use. The personal characteristics of the user, the user's expectations about the drug experience, society's attitudes toward and possible responses to the drug, and the setting in which the drug is used are all major determinants of drug dependence.

Match each drug test to its mechanism for identifying drugs.

GAS CHROMATOGRAPHY (GC) - Separates mixtures based on their distribution between a stationary liquid phase and a moving gas phase. SPECTROPHOTOMETER Measures the selective absorption of a substance when exposed to different types of electromagnetic radiation MASS SPECTROMETRY Shoots a beam of high-energy electrons at the sample, forming ions that pass through an electric or magnetic field where that are separated by their masses.

Gas Chromatography (GC)

Gas chromatography (GC) separates mixtures based on their distribution between a stationary liquid phase and a moving gas phase. - In gas chromatography, the moving phase is called the "carrier gas," which flows through a column constructed of glass. - The stationary phase is a thin film of liquid within the column, which is known as a "capillary column." Capillary columns are composed of glass and are fifteen to sixty meters in length. These types of columns are very narrow, ranging from 0.25 to 0.75 millimeters in diameter. Capillary columns can be made narrow because their stationary liquid phase is actually a very thin film coating the column's inner wall. As the carrier gas flows through the capillary column, it carries with it the components of a mixture that have been injected into the column. Components with a greater affinity for the moving gas phase travel through the column more quickly than those with a greater affinity for the stationary liquid phase. Eventually, after the mixture has traversed the length of the column, it emerges separated into its components. The time required for a component to emerge from the column after its injection into the column is known as the "retention time," which is a useful identifying characteristic. Figure 11-18(a) shows the chromatogram of two barbiturates; each barbiturate has tentatively been identified by comparing its retention time to those of known barbiturates, shown in Figure 11-18(b). - However, because other substances may have comparable retention times under similar chromatographic conditions, gas chromatography cannot be considered an absolute means of identification. Conclusions derived from this technique must be confirmed with other testing procedures. Gas chromatography is widely used because of its ability to resolve a highly complex mixture into its components, usually within minutes. It has the added advantages of being extremely sensitive and yielding quantitative results. Gas chromatography has sufficient sensitivity to detect and quantitate materials down to the nanogram (i.e., 0.000000001 gram).

Hallucinogens

Hallucinogens are drugs that can cause marked alterations in normal thought processes, perceptions, and moods. Perhaps the most popular and controversial member of this class of drugs is marijuana. "A substance that induces changes in normal thought processes, perceptions, and moods

Infrared Spectrophotometry

INFRARED: "(IR) Invisible short frequencies of light before red in the visible spectrum." In contrast to the simplicity of a UV spectrum, absorption in the infrared (IR) region provides a far more complex pattern. Figure 11-24 depicts the IR spectra of heroin and secobarbital. Here, the absorption bands are so numerous that each spectrum can provide enough characteristics to identify a substance specifically. Different materials always have distinctively different infrared spectra; each IR spectrum is therefore equivalent to a "fingerprint" of that substance and no other. This technique is one of the few tests available to the forensic scientist that can be considered specific in itself for identification. The IR spectra of thousands of organic compounds have been collected, indexed, and cataloged as invaluable references for identifying organic substances. The selective absorption of light by drugs in the UV and IR regions of the electromagnetic spectrum provides a valuable technique for characterizing drugs.

Pablo Escobar, Drug Lord Case

In 1989, Forbes magazine listed Pablo Escobar as the seventh richest man in the world. Escobar began his climb to wealth as a teenage car thief in the streets of Medellin, Colombia, and eventually moved into the cocaine-smuggling business. At the peak of his power in the mid-1980s, he was shipping as much as eleven tons of cocaine per flight in jetliners to the United States. Law enforcement officials estimate that the Medellin cartel controlled 80 percent of the world's cocaine market and was taking in about $25 billion annually. Escobar ruthlessly ruled by the gun: murdering, assassinating, and kidnapping. He was responsible for killing three presidential candidates in Colombia, as well as for the storming of the Colombian Supreme Court, which resulted in the murder of half the justices. All the while, Escobar curried favor with the Colombian general public by cultivating a Robin Hood image and distributing money to the poor. In 1991, hoping to avoid extradition to the United States, Escobar turned himself in to the Colombian government and agreed to be sent to prison. However, the prison compound where he was sent could easily be mistaken for a country club. There he continued his high-flying lifestyle, trafficking by telephone and even murdering a few associates. When the Colombian government attempted to move Escobar to another jail, again fearing extradition to the United States, he escaped. Pressured by the U.S. government, Colombia organized a task force dedicated to apprehending Escobar. The manhunt for Escobar ended on December 2, 1993, when he was cornered on the roof of one of his hideouts. A shootout ensued, and Escobar was fatally wounded by a bullet behind the ear. A "drug" can be defined as a natural or synthetic substance that is used to produce physiological or psychological effects in humans or other animals. However, criminalists are concerned primarily with a small number of drugs—many of them illicit—that are commonly used for their intoxicating effects. These include marijuana, the most widely used illicit drug in the United States, and alcohol, which is consumed regularly by ninety million Americans. Drug use has grown and affects all segments of society. Today, approximately twenty-three million people in the United States use illicit drugs. Because of the epidemic proportions of illegal drug use, more than 75 percent of the evidence evaluated by crime laboratories in the United States is drug related (see Figure 11-1). The deluge of drug specimens has necessitated the expansion of existing crime laboratories and the creation of new ones. For many concerned forensic scientists, the crime laboratory's preoccupation with drug evidence represents a serious distraction that takes time away from evaluating evidence related to homicides and other types of serious crimes. However, the increasing caseloads associated with drug evidence have justified the expansion of forensic laboratory services. This expansion has increased the overall analytical capabilities of crime laboratories.

OxyContin

In 1995, the U.S. Food and Drug Administration (FDA) approved the drug OxyContin for use as a painkiller. The active ingredient in OxyContin is oxycodone, a synthetic drug closely related to morphine and heroin in its chemical structure. OxyContin is an analgesic narcotic that has effects similar to those of heroin. It is prescribed for treatment of chronic pain, with doctors writing millions of OxyContin prescriptions each year. The drug has a time-release formula that the manufacturer initially believed would reduce the risk of use and dependence. This has not turned out to be the case. It is estimated that close to a quarter of a million individuals use the drug. Because it is a legal drug that is diverted from legitimate sources, OxyContin is obtained very differently from illegal drugs. Pharmacy robberies, forged prescriptions, and theft of the drug from patients with a legitimate prescription are ways users access OxyContin. Some users visit numerous doctors and receive prescriptions even though their medical condition may not warrant it.

Closer Analysis Bath Salts

It has become trendy in the drug culture to use a group of illicit substances known as "bath salts." These drugs are a mix of chemical derivatives derived from cathinone, a naturally occurring substance found in the khat plant. Cathinone is a stimulant having about half the potency of amphetamine. The allure of using cathinone and its chemical derivatives is to simulate the high associated with methamphetamine and cocaine use. Synthetic derivatives of cathinone are commonly sold in powder, crystal, and liquid forms, but they are available also as tablets and capsules. They are sold in packages to be snorted, ingested, smoked, or injected. Like the side effects associated with methamphetamine or cocaine use, bath salts can induce agitation, violent behavior, and paranoia on the part of the user. A federal law, the Food and Drug Administration Safety and Innovation Act, outlaws two synthetic cathinones, mephidrone and 3,4-methylenedioxypyrovalerone (MDPV), that are common constituents of bath salts.

Name 3 Club Drugs

MDMA GHB Rohypnol

Color Tests

Many drugs yield characteristic colors when brought into contact with specific chemical reagents. Not only do these tests provide a useful indicator of a drug's presence, but they are also used by investigators in the field to examine materials suspected of containing a drug (see Figure 11-12). However, color tests are useful for screening purposes only and are never taken as conclusive identification of unknown drugs.

Electromagnetic Spectrum

Many of us have held a glass prism up toward the sunlight and watched it transform light into the colors of the rainbow. The process of separating light into its component colors is called dispersion. DISPERSION: "The separation of light into its component wavelengths." Visible light usually travels at a constant velocity of nearly three hundred million meters per second. However, on passing through the glass of a prism, each color component of light is slowed to a speed slightly different from those of the others, causing each component to bend at a different angle as it emerges from the prism (see Figure 11-19). This bending of light waves results in a change in velocity called refraction. REFRACTION: "The bending of a light wave caused by a change in its velocity." The observation that a substance has a color is consistent with this description of white light. For example, when light passes through a red glass, the glass absorbs all the component colors of light except red, which passes through or is transmitted by the glass. Likewise, one can determine the color of an opaque object by observing its ability to absorb some of the component colors of light while reflecting others back to the eye. Color is thus a visual indication that objects absorb certain portions of visible light and transmit or reflect others. Scientists have long recognized this phenomenon and have learned to characterize chemical substances by the type and quantity of light they absorb. This has important implications for the identification and classification of forensic evidence. Visible light is only a small part of a large family of radiation waves known as the electromagnetic spectrum (see Figure 11-20). ELECTROMAGNETIC SPECTRUM: "The entire range of radiation energy from the most energetic cosmic rays to the least energetic radio waves." All electromagnetic waves travel at the speed of light (c) and are distinguishable from one another only by their different wavelengths or frequencies. Hence, the only property that distinguishes X-rays from radio waves is the different frequencies the two types of waves possess. X-RAYS: "A high-energy, short-wavelength form of electromagnetic radiation." Similarly, the range of colors that make up the visible spectrum can be correlated with frequency. For instance, the lowest frequencies of visible light are red; waves with a lower frequency fall into the invisible infrared (IR) region. The highest frequencies of visible light are violet; waves with a higher frequency extend into the invisible ultraviolet (UV) region. No definite boundaries exist between any colors or regions of the electromagnetic spectrum; instead, each region is composed of a continuous range of frequencies, each blending into the other. Just as a substance can absorb visible light to produce color, many of the invisible radiations of the electromagnetic spectrum are likewise absorbed. This absorption phenomenon is the basis for spectrophotometry, an analytical technique that measures the quantity of radiation that a particular material absorbs as a function of wavelength or frequency. WAVELENGTH: "The distance between crests" FREQUENCY: "The number of waves that pass a given point per unit of time"

Alcohol (Ethyl Alcohol)

Many people overlook the fact that alcohol is a drug; however, it exerts a powerful depressant action on the central nervous system. Depressant "A substance that slows down, or depresses, the functions of the central nervous system." When alcohol enters the bloodstream, it quickly travels to the brain, where it suppresses the brain's control of thought processes and muscle coordination. Low doses of alcohol tend to inhibit the mental processes of judgment, memory, and concentration. The drinker's personality becomes expansive, and they exude confidence. When taken in moderate doses, alcohol reduces coordination substantially, inhibits orderly thought processes and speech patterns, and slows reaction times. Under these conditions, the ability to walk or drive becomes noticeably impaired. Higher doses of alcohol may cause the user to become highly irritable and emotional; displays of anger and crying are not uncommon. Extremely high doses may cause an individual to lapse into unconsciousness or even a comatose state that can precede a fatal depression of circulatory and respiratory functions. The behavioral patterns of alcohol intoxication vary and depend partly on such factors as the social setting, the amount consumed, and the personal expectation of the individual with regard to alcohol. In the United States, the alcohol industry annually produces more than one billion gallons of spirits, wine, and beer for which ninety million consumers pay nearly $40 billion. Unquestionably, these and other statistics support the fact that alcohol is the most widely used drug

Name 3 Hallucinogens

Marijuana LSD PCP

Closer Analysis Marijuana and Hashish

Marijuana is a weed that will grow wild in most climates. The plant grows to a height of 5 to 15 feet and is characterized by an odd number of leaflets on each leaf. Normally each leaf contains five to nine leaflets, all with serrated or sawtooth edges. The potency of marijuana depends on its form. Marijuana in the form of loose vegetation has an average THC content of about 3 to 4.5 percent. The more potent sinsemilla form averages about 6 to 12 percent in THC content. Sinsemilla is the unfertilized flowering tops of the female Cannabis plants, acquired by removing all male plants from the growing field at the first sign of their appearance. Production of sinsemilla requires a great deal of attention and care, and the plant is therefore cultivated on small plots. Hashish preparations average about 2 to 8 percent THC. On the illicit drug market, hashish (see photo) usually appears in the form of compressed vegetation containing a high percentage of resin. A particularly potent form of hashish is known as "liquid hashish" or "hashish oil." Hashish in this form is normally a viscous substance, dark green with a tarry consistency. Liquid hashish is produced by efficiently extracting the THC-rich resin from the marijuana plant with an appropriate solvent, such as alcohol. The THC content of liquid hashish typically varies from 8 to 22 percent. Because of its extraordinary potency, one drop of the material can produce a "high."

Marijuana

Marijuana is the popular name of the plant Cannabis sativa, a weed that will grow wild in most climates. The Cannabis plant contains a chemical known as "tetrahydrocannabinol," or THC, which produces the psychoactive effects experienced by users. The THC content of Cannabis varies in different parts of the plant. The greatest concentration is usually found in a sticky resin produced by the plant, known as "hashish." Declining concentrations are typically found in the flowers and leaves, respectively. Little THC is found in the stem, roots, or seeds of the plant. The potency and resulting effect of the drug fluctuate, depending on the relative proportion of these plant parts in the marijuana mixture consumed by the user. The most common method of administration is by smoking either the dried flowers and leaves or various preparations of hashish (see Figure 11-5). Marijuana is also occasionally taken orally, typically baked in sweets such as brownies or cookies. Any study of marijuana's effect on humans must consider the potency of the marijuana preparation. An interesting insight into the relationship between dosage level and marijuana's pharmacological effect was presented in the first report of the National Commission on Marijuana and Drug Abuse: At low, usual "social" doses the user may experience an increased sense of well-being; initial restlessness and hilarity followed by a dreamy, carefree state of relaxation; alteration of sensory perceptions including expansion of space and time; a more vivid sense of touch, sight, smell, taste and sound; a feeling of hunger, especially a craving for sweets; and subtle changes in thought formation and expression. To an unknowing observer, an individual in this state of consciousness would not appear noticeably different from his normal state. At higher, moderate doses these same reactions are intensified but the changes in the individual would still be scarcely noticeable to an observer. At very high doses, psychotomimetic phenomena may be experienced. These include distortion of body image, loss of personal identity, sensory and mental illusions, fantasies and hallucinations. Marijuana easily qualifies as the most widely used illicit drug in the United States. For instance, more than forty-three million Americans have tried marijuana, according to the latest surveys, and almost half that number may be regular users. In addition to its widespread illegal use, accumulating evidence suggests that marijuana has potential medical uses. Two promising areas of research are marijuana's reduction of excessive eye pressure in sufferers of glaucoma and the lessening of nausea caused by powerful anticancer drugs. Marijuana may also be useful as a muscle relaxant. Many states began the process of decriminalizing marijuana for medical use in the 1990s and 2000s. In addition, voters in the states of Colorado and Washington opted to legalize the sale of marijuana for recreational use in November 2012. These developments were followed by similar votes in Oregon, Alaska, and the District of Columbia in November 2014, and then four more states (California, Massachusetts, Maine, and Nevada) voted in favor of recreational use in November 2016. Today, more than 20 percent of U.S. population lives in a jurisdiction that has legalized marijuana for recreational purposes. No current evidence suggests that experimental or intermittent use of marijuana causes physical or psychological harm. Marijuana does not cause physical dependence. However, the risk of harm lies instead in heavy, long-term use, particularly of the more potent preparations. Heavy users can develop a strong psychological dependence on the drug. Some effects of marijuana use include increased heart rate, dry mouth, reddened eyes, impaired motor skills and concentration, and frequently hunger, and an increased desire for sweets.

Opiates

Medical professionals apply the term "opiate" to most of the drugs properly classified as narcotics. Opiates behave pharmacologically like morphine, which is a painkiller derived from opium—the gummy, milky juice that exudes from cuts made on the unripe pods of the Asian poppy (Papaver somniferium). Although morphine is readily extracted from opium, the most commonly used opium-based drug is heroin, which is produced by reacting morphine with acetic anhydride or acetyl chloride. Heroin's high solubility in water makes its street preparation for intravenous administration rather simple, and only by injection are heroin's effects felt almost instantaneously and with maximum sensitivity. To prepare the drug for injection, the user frequently dissolves it in a small quantity of water in a spoon. The process can be speeded up by heating the spoon over a candle or several matches. The solution is then drawn into a syringe or eyedropper and injected under the skin. FIGURE 11-3 "The opium poppy and its derivatives. Shown are the poppy plant, crude and smoking opium, codeine, heroin, and morphine." FIGURE 11-4 "Heroin paraphernalia"

Name 3 Narcotics

Morphine Heroin Methadone

Which type of drug is known for inducing sleep and reducing bodily functions such as blood pressure, pulse, and breathing?

Narcotic These drugs have long been used for their pain-relieving properties while recovering from an injury, condition, or medical procedure.

QUICK REVIEW 11.2

Narcotic drugs are analgesics, meaning that they relieve pain by depressing the central nervous system. The most common source for narcotic drugs is opium. Morphine is extracted from opium and used to synthesize heroin. Opiates are not derived from opium or morphine, but they have the same physiological effects on the body. Examples of opiates are methadone and OxyContin (i.e., oxycodone). Hallucinogens cause marked changes in normal thought processes, perceptions, and moods. Marijuana is the most well-known drug in this class. Other hallucinogens include LSD, mescaline, PCP, psilocybin, and MDMA (or Ecstasy). Depressants decrease the activity of the central nervous system, calm irritability and excitability, and produce sleep. Depressants include alcohol (i.e., ethanol), barbiturates, tranquilizers, and various substances that can be sniffed such as airplane glue and model cement. Stimulants increase the activity of the central nervous system and are taken to increase alertness and activity. Stimulants include amphetamines, sometimes known as "uppers" or "speed," and cocaine, which in its freebase form is known as "crack." Club drugs are synthetic drugs that are used at nightclubs, bars, and raves (i.e., all-night dance parties). Some club drugs act as stimulants; others have depressant effects. Anabolic steroids are synthetic compounds that are chemically related to the male sex hormone testosterone. Anabolic steroids are often used by individuals who are interested in accelerating muscle growth.

Place the characteristics of each drug category under its proper title.

Narcotics 1) Induces sleep and depresses vital body functions such as blood pressure, pulse rate, and breathing rate. 2) Means "numbness" or "deadening." Hallucinogens 1) Characterized by an increased sense of well-being and hilarity. 2) Induces changes in normal thought processes, perceptions, and moods. Depressants 1) Produce a relaxing effect, create a feeling of well-being, and produce sleep. 2) Slows down the functions of the central nervous system Stimulants 1) Provide a feeling of well-being and alertness that is followed by a decrease in fatigue and a loss of appetite 2) Speeds up the activity of the central nervous system. Club drugs 1) Synthetic drugs often used at nightclubs, bars, and raves. 2) Often depressants that are connected to drug-facilitated sexual assault, rape, and robbery. Anabolic Steroids 1) Used to promote muscle growth 2) Synthetic compounds that are chemically related to testosterone

Chromatographic Separation

Often the plate is sprayed with a chemical reagent that reacts with the separated substances and causes them to form colored spots. Figure 11-16 shows the chromatogram of a marijuana extract that has been separated into its components by TLC and visualized by having been sprayed with a chemical reagent. Figure 11-17 shows a sample suspected of containing heroin and quinine that has been chromatographed alongside known heroin and quinine standards. The distance the unknown material migrated up the suspect plate is compared to the distances that heroin and quinine migrated up a standard sample plate. If the distances are the same, a tentative identification can be made. However, such an identification cannot be considered definitive because numerous other substances can migrate the same distance up the plate when chromatographed under similar conditions. Thus, TLC alone cannot provide an absolute identification; it must be used in conjunction with other testing procedures to prove absolute identity.

INTRO information

One has only to look into the evidence vaults of crime laboratories to appreciate the assortment of drug specimens that confront the criminalist. The presence of a huge array of powders, tablets, capsules, vegetable matter, liquids, pipes, cigarettes, cookers, and syringes is testimony to the vitality and sophistication of the illicit-drug market. If outward appearance is not evidenced enough of the difficult analytical chore facing the forensic chemist, consider the complexity of the drug preparations themselves. Usually these contain active drug ingredients of unknown origin and identity, as well as additives—for example, sugar, starch, and quinine—that dilute their potency and stretch their value on the illicit-drug market. Do not forget that illicit-drug dealers are not hampered by government regulations that ensure the quality and consistency of their product.

Alcohol/ Marijuana - Psychological Dependence

Our general knowledge of alcohol consumption should warn us of the fallacy of generalizing when attempting to describe the danger of drug use. Obviously, not all alcohol drinkers are psychologically dependent on the drug; most are "social" drinkers who drink in reasonable amounts and on an irregular basis. Many people have progressed beyond this stage and consider alcohol a necessary crutch for dealing with life's stresses and anxieties. However, alcohol users exhibit a wide range of behavioral patterns, and to a large extent, the degree of psychological dependency must be determined individually. Likewise, it would be fallacious to generalize that all users of marijuana can at worst develop a low degree of dependency on the drug. A wide range of factors also influence marijuana's effect, and heavy users of the drug expose themselves to the danger of developing a high degree of psychological dependency.

Which test is commonly used in the identification of drugs?

PCR? NO. The PCR test is used to amplify DNA in the Biology unit. GCMS? YES. Often a gas chromatographer attached to a mass spectrometer are used to confirm the drug components.

The figure below shows a chromatogram of a known mixture of barbiturates. Based on this figure, match the following questions with correct barbiturate:

Purple Liquid: Heroin - Marquis test Pink Layer above blue chloroform layer: Cocaine - Scott test Purple liquid above green vegetation: Marijuana - Duquenois - Levine test Violet blue liquid: Barbiturates - Dillie - Koppanyi test Orange brown liquid: Amphetamine - Marquis test

Following are descriptions of four hypothetical drugs. According to the Controlled Substances Act, match each substance to the drug schedule it would be classified under.

Schedule |: This drug may not be imported or exported without a permit, is subject to manufacturing quotas, and currently has no medical use in the United States. Schedule ||: This drug must be stored in a vault or safe, requires separate record-keeping, and may be distributed with a prescription. Schedule |||: This drug has a high potential for psychological dependence, it currently has accepted medical uses in the United States, and the distributor is not required to report to the U.S. Drug Enforcement Administration. Schedule V: This drug has medical use in the United States, is not limited by manufacturing quotas, and may be exported without a permit.

"Huffing"

Since the early 1960s, "huffing," the practice of sniffing materials containing volatile solvents (e.g., airplane glue or model cement), has grown in popularity. Another dimension has more recently been added to the problem with the increasing popularity of sniffing aerosol gas propellants such as freon. All materials used by huffing contain volatile or gaseous substances that are primarily central nervous system depressants. Although toluene (a solvent used in airplane glue) seems to be the most popular solvent to sniff, others can produce comparable physiological effects. These chemicals include naphtha, methyl ethyl ketone (i.e., antifreeze), gasoline, and trichloroethylene (a dry-cleaning solvent). The usual immediate effects of huffing are a feeling of exhilaration and euphoria combined with slurred speech, impaired judgment, and double vision. Finally, the user may experience drowsiness and stupor, with these depressant effects slowly wearing off as the user returns to a normal state. Although most experts believe that users become psychologically dependent on the effects achieved by huffing, little evidence suggests that solvent inhalation is leads to dependency. However, huffers expose themselves to the danger of liver, heart, and brain damage from the chemicals they have inhaled. Even worse, sniffing of some solvents, particularly halogenated hydrocarbons such as freon and related gases, is accompanied by a significant risk of immediate death.

Closer Analysis Synthetic Cannabis

Synthetic cannabinoids are chemicals designed to mimic the pharmacological effects of naturally occurring cannabinoids. These drugs are generally sold in retail establishments or over the Internet as herbal procedures, potpourri, or incense. Users generally spray the chemicals onto botanical materials and inhale the drug through burning or smoking. Synthetic cannabinoids derive their pharmacological activity from their affinity toward cannabinoid (CB) receptor sites in the brain. Early in their availability, these synthetics went by the common names "K2" and "spice"; however, currently their chemical composition and names have become quite varied as clandestine laboratories have become adept and innovative in modifying their chemical structures seeking to circumvent control by drug laws. Because the chemical structure of synthetic cannabinoids do not resemble marijuana constituents, they cannot be detected by routine drug screening tests. The symptomology associated with the use of synthetic cannabinoids can result in anxiety, agitation, and nausea. A federal law, the Food and Drug Administration Safety and Innovation Act, broadly covers any material that contains a synthetic cannabinoid. Use of the hallucinogen phencyclidine, commonly called "PCP," has recently grown to alarming proportions. Because this drug can be synthesized by simple chemical processes, it is manufactured surreptitiously for the illicit market in so-called clandestine laboratories (see Figure 11-6). These laboratories range from large, sophisticated operations to small labs located in garages or bathrooms. Small-time operators normally have little or no training in chemistry and employ "cookbook" methods to synthesize the drug. Some of the more knowledgeable and experienced operators have been able to achieve clandestine production levels that approach a commercial level of operation. Figure 11-6 A scene from a clandestine drug laboratory. Drug Enforcement Administration Phencyclidine is often mixed with other drugs, such as LSD or amphetamines, and is sold as a powder (known as "angel dust"), capsule, or tablet, or as a liquid sprayed on plant leaves. The drug is smoked, ingested, or sniffed. Following oral intake of moderate doses (1 to 6 milligrams), the user first experiences feelings of strength and invulnerability, along with a dreamy sense of detachment. However, the user soon becomes unresponsive, confused, and agitated. Depression, irritability, feelings of isolation, audio and visual hallucinations, and sometimes paranoia accompany PCP use. Severe depression, tendencies toward violence, and suicide accompany long-term daily use of the drug. In some cases, the PCP user experiences sudden schizophrenic behavior days after the drug has been taken.

The Potential of Some Commonly Used Drugs to Produce Dependence with Regular Use

Table 11.1 categorizes some of the more commonly used drugs according to their effects on the body and summarizes their tendency to produce psychological dependence and to induce physical dependence with repeated use. NARCOTICS DRUG: Morphine Psychological: High Physical: Yes DRUG: Heroin Psychological: High Physical: Yes DRUG: Methadone Psychological: High Physical: Yes DRUG: Codeine Psychological: Low Physical: Yes DEPRESSANTS DRUG: Barbiturates (short-acting) Psychological: High Physical: Yes DRUG: Barbiturates (long-acting) Psychological: Low Physical: Yes DRUG: Alcohol Psychological: High Physical: Yes DRUG: Methaqualone (Quaalude) Psychological: High Physical: Yes DRUG: Meprobamate (Miltown, Equanil) Psychological: Moderate Physical: Yes DRUG: Diazepam (Valium) Psychological: Moderate Physical: Yes DRUG: Chlordiazepoxide (Librium) Psychological: Moderate Physical: Yes STIMULANTS DRUG: Amphetamines Psychological: High Physical: ? DRUG: Cocaine Psychological: High Physical: No DRUG: Caffeine Psychological: Low Physical: No DRUG: Nicotine Psychological: High Physical: Yes HALLUCINOGENS DRUG: Marijuana Psychological: Low Physical: No DRUG: LSD Psychological: Low Physical: No DRUG: Phencyclidine (PCP) Psychological: High Physical: No

Mass Spectrometry

The "Gas Chromatography" section discussed the operation of the gas chromatograph. This instrument is one of the most important tools in a crime laboratory. Its ability to separate the components of a complex mixture is unsurpassed. However, gas chromatography has one important drawback: its inability to produce specific identification. A forensic chemist cannot unequivocally state the identity of a substance based solely on its retention time as determined by the gas chromatograph. Fortunately, by coupling the gas chromatograph to a mass spectrometer, forensic chemists have largely overcome this problem. A mixture's components are first separated on the gas chromatograph. A direct connection between the gas chromatograph column and the mass spectrometer then allows each component to flow into the spectrometer as it emerges from the gas chromatograph. In the mass spectrometer, the material enters a high-vacuum chamber where a beam of high-energy electrons is aimed at the sample molecules. The electrons collide with the molecules, causing them to lose electrons and to acquire a positive charge. These positively charged molecules, or ions, are very unstable or are formed with excess energy and almost instantaneously decompose into numerous smaller fragments. The fragments then pass through an electric or magnetic field, where they 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. In essence, one can think of this pattern as a "fingerprint" of the substance being examined (see Figure 11-25). How GC/MS works. Left to right, the sample is separated into its components by the gas chromatograph, and then the components are ionized and identified by characteristic fragmentation patterns of the spectra produced by the mass spectrometer. Mass spectrometry thus provides a specific means for identifying a chemical structure. It is also sensitive to minute concentrations. Mass spectrometry is widely used to identify drugs; however, further research is expected to yield significant applications for identifying other types of physical evidence. Figure 11-26 illustrates the mass spectra of heroin and cocaine; here, each line represents a fragment of a different mass (actually the ratio of mass to charge), and the line height reflects the relative abundance of each fragment. Note how different the fragmentation patterns of heroin and cocaine are. Each mass spectrum is unique to each drug and therefore provides a specific test for identifying that substance.

Screening and Confirmation

The challenge or difficulty of forensic drug identification comes in selecting analytical procedures that will ensure a specific identification of a drug. Presented with a substance of unknown origin and composition, the forensic chemist must develop a plan of action that will ultimately yield the drug's identity. This plan, or scheme of analysis, is divided into two phases. 1) First, 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 produce characteristic colors for the more commonly encountered illicit drugs. Even if these tests produce negative results, their value lies in having excluded certain drugs from further consideration. 2) Once the number of possibilities has been reduced substantially, the second phase of the analysis must be devoted to pinpointing and confirming the drug's identity. In an era in which crime laboratories receive voluminous quantities of drug evidence, it is impractical to subject a drug to all the chemical and instrumental tests available. Indeed, it is more realistic to look on these techniques as constituting a large analytical arsenal. The chemist, aided by training and experience, must choose tests that will most conveniently identify a particular drug. Forensic chemists often use a specific test to identify a drug substance to the exclusion of all other known chemical substances. A single test that identifies a substance is known as a confirmation. The analytical scheme sometimes consists of a series of nonspecific or presumptive tests. Each test in itself is insufficient to prove the drug's identity; however, the proper analytical scheme encompasses a combination of test results that characterize one and only one chemical substance—the drug under investigation. Furthermore, experimental evidence must confirm that the probability of any other substance responding in an identical manner to the scheme selected is so small as to be beyond any reasonable scientific certainty.

The Role of Computers in Mass Spectrometry

The combination of the gas chromatograph and mass spectrometer (GC/MS) is further enhanced when a computer is added to the system. The integrated gas chromatograph/mass spectrometer/computer system provides the ultimate in speed, accuracy, and sensitivity. With the ability to record and store in its memory several hundred mass spectra, such a system can detect and identify substances present in quantities of only one millionth of a gram. Furthermore, the computer can be programmed to compare an unknown spectrum against a comprehensive library of mass spectra stored in its memory. The advent of personal computers and microcircuitry has enabled the design of mass spectrometer systems that can fit on small tables. Such a unit is pictured in Figure 11-27. With data obtained from a GC/MS determination, a forensic analyst can, with one instrument, separate the components of a complex drug mixture and then unequivocally identify each substance present in the mixture. FIGURE 11-27 A tabletop Gas Chromatograph Mass Spectrometer. (1) The sample is injected into a heated inlet port, and carrier gas sweeps it into the column. (2) The GC column separates the mixture into its components. (3) In the ion source, a filament wire emits electrons that strike the sample molecules, causing them to fragment as they leave the GC column. (4) The quadrupole, consisting of four rods, separates the fragments according to their mass. (5) The detector counts the fragments passing though the quadrupole. The signal is small and must be amplified. (6) The data system is responsible for total control of the entire GC/MS system. It detects and measures the abundance of each fragment and displays the mass spectrum. Research-grade mass spectrometers are found in laboratories as larger, floor-model units

Psychological Dependence

The common denominator that characterizes all types of repeated drug use is the creation of a psychological dependence for continued use of the drug. Most users present quite a typical appearance and remain both socially and economically integrated in the life of the community. The reasons some people abstain from drugs while others become moderately or heavily involved are difficult if not impossible to delineate. Psychological needs arise from numerous personal and social factors that inevitably stem from the individual's desire to create a sense of well-being and to escape from reality. In some cases, the individual may seek relief from personal problems or stressful situations or may be trying to sustain a physical and emotional state that permits an improved level of performance. Whatever the reasons, the underlying psychological needs and the desire to fulfill them create a conditioned pattern of drug use The intensity of the psychological dependence associated with a drug's use is difficult to define and largely depends on the nature of the drug used. For drugs such as alcohol, heroin, amphetamines, barbiturates, and cocaine, continued use is likely to result in a high degree of involvement. Other drugs, such as marijuana and codeine, appear to have a considerably lower potential for the development of psychological dependence. However, this does not imply that repeated use of drugs deemed to have a low potential for psychological dependency is safe or will always produce low psychological dependence. We have no precise way of measuring or predicting the impact of drug use on the individual. Even if a system could be devised for controlling the many possible variables affecting a user's response, the unpredictability of the human personality would still have to be considered.

Closer Analysis What's in that Bag?

The contents of a typical bag of heroin is an excellent example of the uncertainty attached to buying illicit drugs. For many years in the 1960s and into the early 1970s, the average bag contained 15 to 20 percent heroin. Currently, the average purity of heroin obtained in the illicit U.S. market is approximately 35 percent. The user rarely knows or cares what composes the other 65 percent or so of the material. Traditionally, quinine has been the most common diluent of heroin. Like heroin, it has a bitter taste and was probably originally used to obscure the actual potency of a heroin preparation from those who wished to taste-test the material before buying it. Other diluents commonly added to heroin are starch, lactose, procaine (Novocain), and mannitol.

Closer Analysis Controlled Substances Act

The federal Controlled Substances Act establishes five schedules of classification for controlled dangerous substances on the basis of a drug's potential for use, potential for physical and psychological dependence, and medical value. This classification system is extremely flexible in that the U.S. attorney general has the authority to add, delete, or reschedule a drug as more information becomes available. Schedule I. Schedule I drugs have a high potential for use, have no currently accepted medical use in the United States, and/or lack accepted safety for use in treatment under medical supervision. Drugs controlled under this schedule include heroin, marijuana, methaqualone, and LSD. Schedule II. Schedule II drugs have a high potential for use, a currently accepted medical use or a medical use with severe restrictions, and a potential for severe psychological or physical dependence. Schedule II drugs include opium and its derivatives not listed in schedule I, cocaine, methadone, phencyclidine (PCP), most amphetamine preparations, and most barbiturate preparations containing amobarbital, secobarbital, and pentobarbital. Dronabinol, the synthetic equivalent of the active ingredient in marijuana, has been placed in schedule II in recognition of its growing medical uses in treating glaucoma and chemotherapy patients. Schedule III. Schedule III drugs have less potential for use than those in schedules I and II, a currently accepted medical use in the United States, and a potential for low or moderate physical dependence or high psychological dependence. Schedule III controls, among other substances, all barbiturate preparations (except phenobarbital) not covered under schedule II and certain codeine preparations. Anabolic steroids were added to this schedule in 1991. Schedule IV. Schedule IV drugs have a low potential for use relative to schedule III drugs and have a current medical use in the United States; their use may lead to limited dependence relative to schedule III drugs. Drugs controlled in this schedule include propoxyphene (Darvon), phenobarbital, and tranquilizers such as meprobamate (Miltown), diazepam (Valium), and chlordiazepoxide (Librium). Schedule V. Schedule V drugs must show low use potential, have medical use in the United States, and have less potential for producing dependence than schedule IV drugs. Schedule V controls certain opiate drug mixtures that contain nonnarcotic medicinal ingredients. Controlled dangerous substances listed in schedules I and II are subject to manufacturing quotas set by the attorney general. For example, eight billion doses of amphetamines were manufactured in the United States in 1971. In 1972, production quotas were established reducing amphetamine production approximately 80 percent below 1971 levels. The criminal penalties for the unauthorized manufacture, sale, or possession of controlled dangerous substances are related to the schedules as well. The most severe penalties are associated with drugs listed in schedules I and II. For example, for drugs included in schedules I and II, a first offense of individual trafficking is punishable by up to twenty years in prison and/or a fine of up to $1 million for an individual. The table summarizes the control mechanisms and penalties for each schedule of the Controlled Substances Act. The Controlled Substances Act also stipulates that an offense involving a controlled substance analog—a chemical substance substantially similar in chemical structure to a controlled substance—triggers penalties as if it were a controlled substance listed in schedule I. This section is designed to combat the proliferation of so-called designer drugs—substances that are chemically related to some controlled drugs and are pharmacologically very potent. These substances are manufactured by skilled individuals in clandestine laboratories with the knowledge that their products will not be covered by the schedules of the Controlled Substances Act. For instance, fentanyl is a powerful narcotic that is commercially marketed for medical use and is also listed as a controlled dangerous substance. This drug is about a hundred times as potent as morphine. A number of substances chemically related to fentanyl have been synthesized by underground chemists and sold on the street. The first such substance we know of was sold under the street name China White. These drugs have been responsible for more than a hundred overdose deaths in California and nearly twenty deaths in western Pennsylvania. As designer drugs such as China White become identified by drug officials and linked to drug use, they are placed in appropriate schedules. The Controlled Substances Act also reflects an effort to decrease the prevalence of clandestine drug laboratories designed to manufacture controlled substances. The act regulates the manufacture and distribution of precursors, the chemical compounds used by clandestine drug laboratories to synthesize drugs. Targeted precursor chemicals are listed in the definition section of the Controlled Substances Act. Severe penalties are assigned to a person who possesses a listed precursor chemical with the intent to manufacture a controlled substance or who possesses or distributes a listed chemical knowing, or having reasonable cause to believe, that the listed chemical will be used to manufacture a controlled substance. In addition, precursors to PCP, amphetamines, and methamphetamines are enumerated specifically in schedule II, making them subject to regulation in the same manner as other schedule II substances.

Drug Laws

The provisions of drug laws are of particular interest to the criminalist, for they may impose specific analytical requirements on drug analysis. For example, the severity of a penalty associated with the manufacture, distribution, possession, and use of a drug may depend on the weight of the drug or its concentration in a mixture. In such cases, the chemist's report must contain all information that is needed to properly charge a suspect under the provisions of the existing law. The provisions of any drug-control law are an outgrowth of national and local law enforcement requirements and customs, as well as the result of moral and political philosophies. These factors have produced a wide spectrum of national and local drug-control laws. Although their detailed discussion is beyond the intended scope of this book, a brief description of the U.S. federal law known as the Controlled Substances Act will illustrate a legal drug classification system that has been created to prevent and control drug use. Many states have modeled their own drug-control laws after this act, an important step in establishing uniform drug-control laws throughout the United States.

Measure and define a given drug's influence

The questions of how to define and measure a given drug's influence on the individual and its danger to society are difficult to assess. The nature and significance of drug dependence must be considered from two overlapping points of view: the interaction of the drug with the individual, and the drug's impact on society. It will be useful to approach the problem from two distinctly different aspects of human behavior: - psychological dependence and physical dependence.

Club Drugs

The term "club drugs" refers to synthetic drugs that are often used at nightclubs, bars, and raves (i.e., all-night dance parties). Substances that are used as club drugs include, but are not limited to, methylenedioxymethamphetamine (MDMA) (also known as Ecstasy; see Figure 11-10), gamma hydroxybutyrate (GHB), Rohypnol ("roofies"), ketamine, and methamphetamine. These drugs have become popular on the dance scene as a way to induce the rave experience. A high incidence of use has been found among teens and young adults.

Narcotic Drugs

The term narcotic is derived from the Greek word narkotikos, meaning "numbness" or "deadening." Narcotic: "A drug that induces sleep and depresses vital body functions such as blood pressure, pulse rate, and breathing rate." Although pharmacologists classify narcotic drugs as substances that relieve pain and produce sleep, the term "narcotic" has become popularly associated with any drug that is socially unacceptable. As a consequence of this incorrect perception, many drugs are improperly called "narcotics." This confusion has produced legal definitions that differ from the pharmacological actions of many drugs. For example, until the early 1970s, most drug laws in the United States incorrectly designated marijuana as a narcotic. Even today, federal law classifies cocaine as a narcotic drug; however, pharmacologically speaking, cocaine is actually a powerful central nervous system stimulant, possessing properties opposite those normally associated with the depressant effects of a narcotic.

Stimulants

The term stimulants refers to a range of drugs that stimulate, or speed up, the central nervous system. Stimulants "A substance that speeds up, or stimulates, the activity of the central nervous system."

Thin-Layer Chromatography

Thin-layer chromatography (TLC) uses a solid stationary phase and a moving liquid phase to separate the constituents of a mixture. TLC is a powerful tool for solving many of the analytical problems presented to the forensic scientist. The method is both rapid and sensitive; moreover, less than one hundred micrograms of suspect material is required for the analysis. In addition, the equipment necessary for TLC work has minimal cost and space requirements. Importantly, numerous samples can be analyzed simultaneously on one thin-layer plate. This technique is principally used to detect and identify components in complex mixtures. In TLC, the components of a suspect mixture are separated as they travel up a glass or plastic plate, eventually appearing as a series of dark or colored spots on the plate. This action is then compared to a standard sample separation of a specific drug, such as heroin. If both the standard and the suspect substances travel the same distance up the plate, they can tentatively be identified as being the same substance. A thin-layer plate is prepared by coating a glass plate or plastic backing with a thin film of a granular material, usually silica gel or aluminum oxide. This granular material serves as the solid stationary phase and is usually held in place on the plate with a binding agent such as plaster of paris. If the sample to be analyzed is a solid, it must first be dissolved in a suitable solvent; then a few microliters of the solution are spotted with a capillary tube onto the granular surface near the lower edge of the plate. A liquid sample may be applied directly to the plate in the same manner. The plate is then placed upright in a closed chamber that contains a selected liquid, but the liquid must not touch the sample spot. The liquid slowly rises up the plate by capillary action. This rising liquid is the moving phase in TLC. As the liquid moves past the sample spot, the components of the sample become distributed between the stationary solid phase and the moving liquid phase. The components with the greatest affinity for the moving phase travel up the plate faster than those that have greater affinity for the stationary phase. When the liquid front has moved a sufficient distance (usually 10 centimeters), the development is complete, and the plate is removed from the chamber and dried.

Ultraviolet and Visible Spectrophotometry

ULTRAVIOLET: Invisible long frequencies of light beyond violet in the visible spectrum. Ultraviolet (UV) and visible spectrophotometry measure the absorption of UV and visible light as a function of wavelength or frequency. For example, the UV absorption spectrum of heroin shows a maximum absorption band at a wavelength of 278 nanometers (see Figure 11-22). This shows that the simplicity of a UV spectrum facilitates its use as a tool for determining a material's probable identity. For instance, a white powder may have a UV spectrum comparable to heroin and therefore may be tentatively identified as such. (Fortunately, sugar and starch, common diluents of heroin, do not absorb UV light.) This technique, however, does not provide a definitive result; other drugs or materials may have a UV absorption spectrum similar to that of heroin. Nevertheless, UV spectrophotometry is often useful in establishing the probable identity of a drug. For example, if an unknown substance yields a UV spectrum that resembles that of amphetamine (see Figure 11-23), thousands of substances are immediately eliminated from consideration, and the analyst can begin to identify the material from a relatively small number of possibilities. A comprehensive collection of UV drug spectra provides an index that can rapidly be searched in order to tentatively identify a drug or, failing that, at least to exclude certain drugs from consideration.

11.4 Collection and Preservation of Drug Evidence

Understand the proper collection and preservation of drug evidence.

Forensic chemist

When forensic chemist picks up a drug specimen for analysis, they can expect to find just about anything, so all contingencies must be prepared for. The analysis must leave no room for error because its results will have a direct bearing on the process of determining the guilt or innocence of a defendant. There is no middle ground in drug identification—either the specimen is a specific drug or it is not—and once a positive conclusion is drawn, the chemist must be prepared to support and defend the validity of the results in a court of law.

Physical Dependence

Whereas emotional well-being is the primary motive leading to repeated and intensive use of a drug, certain drugs, when taken in sufficient dose and frequency, are capable of producing physiological changes that encourage their continued use. Once the user abstains from such a drug, severe physical illness follows. The desire to avoid this withdrawal sickness or abstinence syndrome ultimately causes physical dependence. Hence, for the individual with a substance use problem who is accustomed to receiving large doses of heroin, the thought of abstaining and encountering body chills, vomiting, stomach cramps, convulsions, insomnia, pain, and hallucinations is a powerful inducement for continued drug use. Interestingly, some of the more widely used drugs have little or no potential for creating physical dependence. Drugs such as marijuana, lysergic acid diethylamide (LSD), and cocaine create strong anxieties when their repeated use is discontinued; however, no medical evidence attributes these discomforts to physiological reactions that accompany withdrawal sickness. On the other hand, use of alcohol, heroin, and barbiturates can result in development of physical dependency. Physical dependency develops only when the drug user adheres to a regular schedule of drug intake; that is, the interval between doses must be short enough so that the effects of the drug never wear off completely. For example, if a person is regularly injecting heroin, the interval between doses does not usually exceed six to eight hours before physical withdrawal symptoms begin. Beyond this time, the user begins to experience the uncomfortable symptoms of withdrawal. Many heroin users avoid taking the drug regularly for fear of becoming physically dependent on it. Similarly, the risk of developing a physical dependence on alcohol becomes greatest when the consumption is characterized by a continuing pattern of daily use in large quantities.

List 3 Depressants

Xanax Alcohol Barbiturates

GHB and Rohypnol

are central nervous system depressants that are often connected with drug-facilitated sexual assault, rape, and robbery. Effects accompanying the use of GHB include dizziness, sedation, headache, and nausea. Recreational users have reported euphoria, relaxation, disinhibition, and increased libido (i.e., sex drive). Rohypnol causes muscle relaxation, loss of consciousness, and an inability to remember what happened during the hours after ingesting the drug. Users of this drug are at particular risk of sexual assault because victims are physically unable to resist the attack. Effects are even stronger when the drug is combined with alcohol because the user experiences memory loss, blackouts, and disinhibition. Unsuspecting victims of intentional druggings become drowsy or dizzy. Drugs such as Rohypnol and GHB are odorless, colorless, and tasteless, and thus remain undetected when slipped into a drink.

Forensic chemists normally rely on several tests for a routine drug-identification scheme:

color tests, microcrystalline tests, chromatography, spectrophotometry, and mass spectrometry

The social impact of drug dependence is

directly related to the extent to which the user has become preoccupied with the drug. Here, the most important element is the extent to which drug use has become interwoven in the fabric of the user's life. The more frequently the drug satisfies the person's need, the greater the likelihood that they will become preoccupied with its use, with a consequent neglect of individual and social responsibilities. Personal health, economic relationships, and family obligations may all suffer as the drug-seeking behavior increases in frequency and intensity and dominates the individual's life. The extreme of drug dependence may lead to behavior that has serious implications for the public's safety, health, and welfare. Drug dependence in its broadest sense involves much of the world's population. As a result, a complex array of individual, social, cultural, legal, and medical factors ultimately influence society's decision to prohibit or impose strict controls on a drug's distribution and use. Invariably, society must weigh the beneficial aspects of the drug against the ultimate harm its use will do to the individual and to society as a whole. Obviously, many forms of drug dependence do not carry sufficient adverse social consequences to warrant their prohibition, as illustrated by the widespread use of such drug-containing substances as tobacco and coffee. Although the heavy and prolonged use of these drugs may eventually damage body organs and injure an individual's health, there is no evidence that they result in antisocial behavior, even with prolonged or excessive use. Hence, society is willing to accept the widespread use of these substances. We are certainly all aware of the disastrous failure of the prohibition by the United States of alcohol use during the 1920s and also of the current debate on whether marijuana should be legalized. Each of these issues emphasizes the delicate balance between individual desires and needs and society's concern with the consequences of drug use; moreover, this balance is continuously subject to change and reevaluation.

Dependence on different drugs

exists in numerous patterns and in all degrees of intensity, and depends on the nature of the drug, the route of administration, the dose, the frequency of administration, and the individual's rate of metabolism.

MDMA, or Ecstasy

is a synthetic, mind-altering drug that exhibits many hallucinogenic and amphetamine-like effects. Ecstasy was originally patented as an appetite suppressant and was later discovered to induce feelings of happiness and relaxation. Recreational drug users find that Ecstasy enhances self-awareness and decreases inhibitions. However, seizures, muscle breakdown, stroke, kidney failure, and cardiovascular system failure often accompany chronic use of Ecstasy. In addition, chronic use of Ecstasy leads to serious damage to the areas of the brain responsible for thought and memory. Ecstasy increases heart rate and blood pressure; produces muscle tension, teeth grinding, and nausea; and causes psychological difficulties such as confusion, severe anxiety, and paranoia. The drug can cause significant increases in body temperature from the combination of the drug's stimulant effect with the often hot, crowded atmosphere of a rave club.

Codeine

is also present in opium, but it is usually prepared synthetically from morphine. It is commonly used as a cough suppressant in prescription cough syrup. Codeine, only one-sixth as strong as morphine, is not an attractive street drug for users.

Preparation of drug evidence for submission to the crime laboratory

is normally relatively simple and accomplished with minimal precautions in the field. The field investigator must ensure that the evidence is properly packaged and labeled for delivery to the laboratory. Considering the countless forms and varieties of drug evidence that are seized, it is not practical to prescribe any single packaging procedure for fulfilling these requirements. Generally, common sense is the best guide in such situations, keeping in mind that the package must prevent loss and/or cross-contamination of the contents. Often, the original container in which the drug was seized will meet these requirements. Specimens suspected of containing volatile solvents, such as those involved in glue-sniffing cases, must be packaged in an airtight container to prevent evaporation of the solvent. All packages must be marked with sufficient information to ensure identification by the officer in future legal proceedings and to establish the chain of custody. To aid the drug analyst, the investigator should supply any background information that may relate to a drug's identity. Analysis time can be markedly reduced when the chemist has this information. For the same reason, the results of drug-screening tests used in the field must also be transmitted to the laboratory. However, although these tests may indicate the presence of a drug and may help the officer establish probable cause to search and arrest a suspect, they do not offer conclusive evidence of a drug's identity.

Ketamine

is primarily used in veterinary medicine as an animal anesthetic. When used by humans, the drug can cause euphoria and feelings of unreality accompanied by visual hallucinations. Ketamine can also cause impaired motor function, high blood pressure, amnesia, and mild respiratory depression.

The need for a drug brought about by its regular use and characterized by withdrawal sickness when administration of the drug is abruptly stopped is known as ______ dependence. In contrast, the conditioned use of a drug caused by underlying emotional needs is ______ dependence.

physical, psychological

In assessing the potential danger of drugs...

society has become particularly conscious of their effects on human behavior. In fact, the first drugs to be regulated by law in the early years of the twentieth century were those deemed to have "habit-forming" properties. The early laws were aimed primarily at controlling opium and its derivatives; cocaine; and, later, marijuana. The ability of a drug to induce dependence after repeated use is submerged in a complex array of physiological and social factors.

Most color and crystal tests are largely empirical

that is, scientists do not fully understand why they produce the results they do. From the forensic chemist's point of view, this is not important. When the tests are properly chosen and used in proper combination, they reveal characteristics that identify the substance as a certain drug to the exclusion of all others.