JS 112: Forensic Chemistry: Drugs/ToxI. Pre Class Activities

a. Announcements and Assignments

II. Learning objectives a. Drugs- What is a drug?b. Define psychological and physical dependencec. Name and classify commonly abused drugsd. Describe tendency to develop psychological and physical dependency

for the more commonly abused drugse. Describe the schedules of Controlled Substances Actf. Describe lab tests that forensic chemists normally rely upon to

comprise a routine drug id schemeg. Discuss the proper collection and preservation of drug evidence

Web links toxicology: http://home.lightspeed.net/~abarbour/vlibft.html

Assignments

a. Assignments:a. Read Chapters 8 and 9- Drugs and Toxicology for weds.b. Read Chapters 10 and 12 Bloodstains and Serology for mon.

a. Extra credit:Due Monday 19 April a. Find 1 article on alcohol abuse leading to a fatality e.g. DUI from a news

story within the last 3 months.b. Write a 300 word summary and 3 questions and 3 answers on the article. Be

prepared to discuss it in class.

b. Bring Lab books with Reports Weds- c. Study for quiz for Monday 19 April on Drugs, Dr. Orrego Lecture and

Blood reading.

What is a Drug?

• A drug is a natural or synthetic substance that is used to produce physiological or psychological effects in humans or other higher order animals

Drug Dependence

• Psychological dependence- The conditioned use of a drug caused by underlying emotional needs.

• Physical dependence- Physiological need for a drug that has been brought about by its regular use. Dependence is characterized by withdrawal sickness when administration of the drug is abruptly stopped.

Some Typical Drugs

Marijuana

Heroin Cocaine

Potential of commonly abused drugs to produce dependency with regular use

• Drug Psychological Physical• Narcotics

– Morphine High Yes– Heroin High Yes– Methadone High Yes– Codeine Low Yes

• Depressants– Barbiturates (short-acting)High Yes– Barbiturates (long-acting) Low Yes– Alcohol High Yes– Diazepam (Valium) Moderate Yes

• Stimulants– Amphetamines High ?– Cocaine High No– Caffeine Low No (?)– Nicotine High Yes

• Hallucinogens– Marijuana Low No– LSD Low No– PCP High No

Factors influencing control

• Individual, social, cultural, legal, and medical• Weigh the beneficial aspects of the drug vs harm

the abuse will do to the individual and society• Prohibition of alcohol led to disastrous failure

leading to the current debate over legalizing marijuana- Balance between individual desires and needs and society’s concern with the consequences of drug abuse.

Narcotic Drugs• Narcotic- Analgesic or pain-killing substance that depresses vital

body functions such as blood pressure, pulse rate, and breathing rate. The regular administration of narcotics will produce physical dependence.

• Analgesic- A drug or substance that lessens or eliminates pain. • Opium derivatives: Morphine, Heroin, Codeine derived from

opium. • Opiates- not derived from opium but similar physiological

effects– OxyContin – oxycodon for chronic pain- abused by 250,000! – Methadone- quelled addict desire for heroine. Now used for pain relief and

is abused increasingly

HallucinogensHallucinogen- A substance that induces changes in mood, attitude, thought, or perception.Examples:

Marijuana- Cannabis sativa L.: most widely used illicit drug US

Hashish- sticky resin secretion extracted by soaking in a solvent such as alcohol

Sensemilla-potent form of marijuana- unfertilized flowering tops of female Cannabis plant

43 million tried it, 50% addicted

Hallucinogens- Marijuana

3000 years2737 BC Emperor Shen Nung1000 BC Hindu- India500AD Persia and Arabia1929 into US via Mexico1964 discover tetrahydrocannabinol is

the substance responsible for hallucinogenic property

Hallucinogens- Marijuana

• Increased sense of well being

• Dreamy carefree state

• Vivid sense of touch, sight, smell, taste, sound

• Hunger

• Craving sweets

• Not noticeably different from normal state

Other Hallucinogens

• Lysergic acid diethylamide- LSD- derived from fungus ergot attacking grasses: Potent 25 ug lasts 12 hours

• Mescaline• Phencyclidine (PCP)-clan labs: 1-6mg feelings of

strength, and detachment. Soon unresponsive, confused and agitated… paranoia and depression

• Psilocybin• Methylenedioxymethamphetamine- MDMA or

ecstasy

Depressants• Depressant- a substance used to depress the functions of the central nervous

system. Depressants calm irritability and anxiety and may induce sleep. • Alcohol: $40 billion annually US- most widely used and abused drug• Barbiturates: downers- relax and create a feeling of well being- 25 in use in

medicine- 5: amobarbital, secobarbital, phenobarbital, pentobarbital and butabarbital used for most: “barbs, yellow jackets, blue devils and reds”10-70mg dose. Methaqualone (Quaalude) powerful sedative.

• Tranquilizers: relax “without impairment”- Reserpine and chlorpromazine reduce anxiety of mental patients- mild tranquilizers- diazepam (Valium), chlordiazepozide (Librium) and meprobamate (Miltown) produce psychological and physical dependancy

• Glue sniffing and gas propellants: exhilaration and euphoria- liver, heart and brain damage

Stimulants• Stimulant- A substance taken to increase alertness or activity. • Amphetamines: synthetic drug: uppers or speed: 5-20 mg.

Amphetamine or Methamphetamine. Restlessness, instability and depression. Inject or smoke- Ice

• Cocaine- Sigmund Freud experiments with drug- the need for food and sleep was completely banished. Once used for local pain killer. Powerful stimulant. Most commonly sniffed through mucus membranes of the nose. Crack smoked. Crack users rarely kick the habit. Abuse on the rise. Not harmless. - mental depression, cardiac arrest

Club Drugs

• Club drugs- Synthetic drugs that are used at nightclubs, bars, and raves. Club drugs include, but or not limited to, MDMA (ecstasy), GHB (gamma hydroxybutyrate), Rohypnol (roofies), Ketamine, and Methamphetamine. MDMA

• GHB-gamma hydoxybutyrate, • Rohyphnol (roofies)- muscle relaxation and loss

of consciousness- rape drug• Ketamine• Methamphetame

Anabolic Steroids

Anabolic steroids- Steroids that promote muscle growth. Chemically related to male sex hormone, testosterone.

Widespread attention for enhancing athletic performance. In 1991, the US government classified them as controlled dangerous substances

Drug Control LawsControlled Substances Act

Legal Drug Classification System to prevent and control drug abuse

5 schedules of classification for controlled dangerous substances on the basis of a drug’s potential for abuse, potential fo physical and psychological dependence and medical value

Flexible: as the US attorney general has the authority to add, delete, or reschedule a drug as more information becomes available

Schedules I and II are subject to manufacturing quota

Criminal penalties for unauthorized manufacture, sale or possession are related to the schedules. Most severe are for I and II punishable by up to 20 years and 1 million for individual or up to 5 million for other than individuals

Controlled Substances Act Schedule

Drug Identification• Selection of an Analytical Scheme. • Factors including amount of substance to be analyzed, time available, and disposition of the

analyzed material. • The general principles that are followed when developing an Analytical Scheme are as

follows. 1. Visual examinations remain the first method employed. 2. Examinations must move from general to specific. 3. The schemes and processes must adhere to generally accepted processes and tests accepted

in the field. 4. Whenever possible perform at least one specific test. 5. Pay attention to the possibility that the sample may be needed as an exhibit in court. 6.If there is not enough material for a complete battery of tests those that do not destroy the

sample should be performed first.

7. Use the tests that have the most telling results.

Drug Identification

• Screening test- A test that is nonspecific and preliminary in nature to reduce the possibilities to a manageable number- series of color tests.

• Once the number of possibilities has been substantially reduced, the second phase of analysis must be devoted to pinpointing and confirming the drug’s identity

• Confirmation- A single test that specifically identifies a substance.

Drug Identification tests

• Color tests

• Microcrystalline tests

• Chromatography- TLC

• Spectrophotometry- UV Spec, IR Spec

• Mass spectrometry- coupled to GC: GC-MS

Screening Tests

•Provides information about class of drugs involved

Color tests• Marquis (2 % formaldehyde in sulfuric acid): Purple- heroin, morphine

and opium derivatives. Orange brown for amphetamines and methamphetamines

• Dillie-Koppanyi (1% cobalt acetate in methanol followed by 5% isopropylamine in methanol)- Violet-blue for barbituates

• Duquenois-Levine (A= 2% vanillin and 1% acetaldehyde in EtOH- B= concentrated HCL and C= chloroform) Purple in C layer for marijuana

• Van Urk (1% p-dimethyaminobenzaldehyde in 10% concentrate HCl and EtOH). Blue purple- LSD

• Scott Test (A=2% cobalt thiocyanate dissolved in H20, B= HCl and C=Chloroform) Cocaine – A blue, B pink and C blue reappears

Microcrystalline Tests

• Microcrystalline tests- Tests to identify specific substances by the color and morphology of the crystals formed when the substance is mixed with specific reagents.

Chemical Microscopy

• Reagents are aqueous solutions of metallic salts

• Drug materials form complexes with reagent

• Complexes are crystals• Observed microscopically• Closely related materials give

very different crystals, easily distinguished Heroin with Mercuric Iodide

Confirmatory Tests

• Chromatography- TLC and GC• FTIR- Fourier Transform Infrared Spec• Chemical Microscopy

Thin Layer Chromatography (TLC -1)• Moving liquid phase, solid

stationary phase• TLC Procedure

– Sample is dissolved in a solvent– Spotted onto the lower edge of the plate – The plate is placed into a closed chamber

with liquid– The liquid slowly rises up by capillary

action. Separation occurs as the components with the greatest affinity for the moving phase migrate faster

– Visualized UV fluorescence or developed with a chemical reagent spray color spots

TLC -2

• Questioned sample (Q) must be developed alongside a standard or known (K) sample. If Q and K travel the same distance up the plate from the origins then they can be tentatively identified as the same

• ID cannot be considered definitive as other materials may have similar migration

• Distance traveled up can be assigned an R f value = distance traveled by the component divided by the distance traveled by the liquid phase. For example if the moving phase travels 10cm and spot 8cm then R f = 8cm/10cm = 0.8

• Rapid and sensitive down to 100ug• Principal application is detection and identification of components in a

complex mixture– Separate drugs from diluents– Need to know something about identity from other tests– Complements color and crystal tests

Q K

Spectrophotometer

• Instrument used to measure and record the absorption spectrum of a chemical substance

• Components- 1. Radiation source

– 1- Radiation source (UV, vis, IR)

– 2. Monochromator or frequency selector

– 3. Sample holder

– 4. Detection to convert electromagnetic radiation into an electric signal (digitizer)

– 5. Recorder

• UV spec - useful to establish probable identity of drugs

• FTIR- spedivically identify a substance

UV and Visible Spectrophotometry

• Measures the absorbance of UV and visible light as a function of wavelength or frequency

• UV spec of heroin has max absorption at 278nm providing materials probable identity

• Will not provide definitive result - other material may have a similar UV absorption

IR Spectrum• IR specs provide far more

complex patterns• Different materials always

have distinctively different IR spectra

• Each IR spectra is equivalent to a “fingerprint” of that substance and no other

• Fourier transform infrared spectrophotometer FT-IR

• Considered specific in itself for identification

GC- Mass Spectrometry

Collection and Preservation of Drug Evidence

• Simple task with minimal precautions• Properly packaged and labeled• Prevent loss and cross contaminations• Volatiles in airtight container• Marked with information to ensure identification

for future legal proceedings and to establish the chain of custody

• Helps to have background information and any test results completed in the field

Summary 1

Drug is a natural or synthetic substance that is used to produce physiological or psychological effects in humans or other higher order animals

Narcotic- Analgesic or pain-killing substance that depresses vital body functions such as blood pressure, pulse rate, and breathing rate. The regular administration of narcotics will produce physical dependence. Examples are the opium derivatives and opiates

Hallucinogen- A substance that induces changes in mood, attitude, thought, or perception. Examples are marijuana, LSD, PCP and MDMA

Summary 2

• Depressant- a substance used to depress the functions of the central nervous system. Depressants calm irritability and anxiety and may induce sleep. Examples are alcohol, barbituates, tranquilizers and glue sniffing

• Stimulant- A substance taken to increase alertness or activity. Examples are amphetamines and cocaine

• Club drugs- Synthetic drugs that are used at nightclubs, bars, and raves. Club drugs include, but or not limited to, MDMA (ecstasy), GHB (gamma hydroxybutyrate), Rohypnol (roofies), Ketamine, and Methamphetamine. MDMA

• Anabolic steroids- Steroids that promote muscle growth. Chemically related to male sex hormone, testosterone.

Summary 3

• Controlled substances schedules are a legal drug classification system to prevent and control drug abuse

• There are 5 schedules with I and II being the most dangerous with accordingly the highest penalties for manufacture, sale or possession

• Drug chemists conduct screening tests to narrow down the possibilities and then confirmatory tests to identify the drug. Typically FTIR or GCMS is used

• Collection of drug evidence should be done to prevent loss, and contamination. All evidence should be marked and chain of custody established.