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UNIT 2: FORENSIC CHEMISTRY: INTRODUCTION: Science is the careful observation of nature. By making careful observations scientists can develop guesses (called hypotheses) about why things occur the way they do. Carrying out experiments further tests these hypotheses.. If any of the experiments do not support the hypothesis, it is discarded and a new one is proposed, but if all the experimentation supports the hypothesis, it is accepted by the scientific community and called a theory. Science is therefore testable, tentative, and explanatory. Physical sciences include those sciences that study nonliving systems. Of particular importance to the field of forensic science are chemistry, physics, and geology. The physical sciences unit is the largest unit of the crime lab, and the largest part of this unit is the chemistry Chemistry is the science that studies matter and the changes it can undergo. The reason for a large proportion of the crime lab being devoted to chemistry is the need for the analysis of drug evidence. The U.S. Constitution guarantees a defendant the right to a speed} trial, and this requires a chemical analysis of drug evidence before the case can go to trial. The bulk of the physical evidence analyzed by crime labs today is drug-related. MATTER AND ATOMS: Matter is defined as anything that has mass. Matter can be divided into pure substances and mixtures. Pure substances: , like water and gold, have a definite composition. Mixtures, such as saltwater and coffee, have a composition that can vary. Mixtures can further be classified as homogeneous or heterogeneous. A homogeneous mixture, such as a glass of homogenized milk, has the same composition throughout the mixture. A heterogeneous mixture, such as oil mixed with water, has a composition that varies throughout the mixture. Pure substances can be further classified as elements or compounds. Elements are the basic building blocks of matter compounds are chemical combinations of two or more different elements. Gold is an example of an element, and water is an example of a compound (water is a chemical combination of the elements hydrogen and oxygen). There are presently 115 different known elements, but all the elements after uranium (number 92) do not exist in nature. Elements have one- or two-letter abbreviations called chemical symbols. Hydrogen, for example, has the symbol H, while helium has the symbol He. Two-letter symbols are needed since there are only 26 letters in the alphabet. When two letters are used to designate an element, the first is always capitalized and the second is always lowercase. Thus Co is the symbol for the element cobalt, while CO stands for the compound carbon monoxide, which is composed of the elements carbon and oxygen. ATOMS: The Greek philosopher Democritus (ca. 450 B.C.) believed that if an element was cut up into smaller and smaller pieces, eventually there would come a point where the matter could no longer be divided. He called this ultimately tiny particle atomos from the Greek meaning "cannot be cut." From this, the present-day word atom originates. All matter is composed of atoms. Elements are the different types of atoms that exist. Atoms themselves are composed of three particles, proton neutrons, and electrons. A proton has a relative charge of+1, and an electron has a relative charge of-1 (a neutron has no charge). Since all atoms charge of zero, the number of protons must equal the number electrons. Neutrons and protons are located in a region at the center of atom called the nucleus. Electrons orbit the space surrounding the nucleus called the electron cloud. The number of protons in the nucleus defines what element an atom is. The atomic number is the number of protons in the nucleus of an atom. The periodic table of the elements arranges all the elements by atomic number ORGANIC CHEMISTRY There are many branches of chemistry, but the three most important to forensic science are organic, inorganic, and analytical. Organic chemistry is the study of matter that contains the element carbon. Inorganic chemistry is the study of matter that does not contain the element carbon. Of the compounds listed in the table below, the first three are inorganic and the second three are organic. Arsenic trioxide As203 Inorganic Silver nitrate AgN03 Inorganic Table salt NaCl Inorganic Curare (curine) C18H19N3 Organic Strychnine C21H22N202 Organic Sarin C4H10F02P Organic From a forensic point of view it is important to be able to distinguish between organic and inorganic compounds. Organic samples often contain a complicated mixture of compounds. Not only does this require extra steps in the laboratory analysis, but organic compounds are also more susceptible to degradation due to heat, temperature, humidity, and microorganisms. Curare can break down hi body tissue in a matter of days. Therefore, the investigator has much less time to collect organic samples and submit them to the crime lab. Once at the crime lab, organic samples are normally kept in a walk-in refrigerator at 4°C to ensure preservation. Organic chemicals offer the greatest diversity of any type of compound. Of the more than 20 million known compounds, about 95% are organic. Many poisons, such as, curare and strychnine isolated from living systems such as plants. Two of the most toxic compounds known are tetrodotoxin (from the puffer fish) and botulinum toxin (from the bacterium Clostridium botulinum). The botulinum toxin is so lethal that 1 g (about one-fifth of a teaspoon) could kill 1 million people. ORGANIC COMPOUNDS: Forensic often analyze stomach content during an autopsy by weighing the contents of the stomach for the presence of poisons. The type and amount of the drug can be critical information for a forensics investigator. As can the contents of the stomach. Listed below are the 4 basic organic classes ( digested food can be tested for these classes to confirm or deny suspect statements) . 1. carbohydrates; used by the body as source of energy. 3major groups: a. monosaccharide: simple sugar containing 3-7 carbon atoms. Ex glucose, fructose, galactose ( all with a C6H12O6 formula) Test reagent that is used for identification for monosaccharides is Benedicts solution: Positive test is a green color in the presence of a small amounts of the simple sugar, orange with medium amounts and finally brick red in the presence of a large amount of the simple sugar. b. disaccharide: Double sugar composed of 2 monosaccharides joined together Ex glucose + fructose---- sucrose, glucose + galactose ----lactose glucose + glucose -----maltose No TEST FOR DISSACHARIDE 2. Polysaccharide: starch—3 or more monosaccharides joined together. Test reagent is using Iodine and a positive test is a black-blue color. 3. lipids; Includes fats and steroids, fat is used as an energy source. Test is by using unglazed paper and looking for a translucent spot upon drying. 4. Proteins; Major molecule for the formation of amino acids, enzymes, hormones, clotting factors. And vitamins. Test is Biuret with a positive test turning purple or violet in color 4. Nucleic Acids-Composed of carbon, hydrogen, oxygen, nitrogen and phosphorus . Two Types: a. Deoxyribonucleic acid - DNA 1.) has 4 nitrogen bases - adenine, thymine, cytosine, guanine 2.) contains sugar deoxyribose 3.) contains phosphate group 4.) is double helix with shape Like twisted ladder. Sides of ladder composed of sugar & phosphate with nitrogen bases making rungs of ladder. b. Ribonucleic acid - RNA 1.) has 4 nitrogen bases - adenine, uracil, cytosine, guanine 2.) contains sugar ribose 3.) contains phosphate group 4.) is a single strand ENZYMES – organic catalyst that speed up reaction without taking part in the reaction. Enzymes serve as catalyst by: 1. increasing frequency of collisions 2. lowering activation energy 3. properly orienting colliding molecules Characteristics of enzymes 1. 2. 3. 4. 5. 6. 7. enzymes are proteins have molecular weight of 10,000 to millions enzymes are substrate specific (the substrate is the molecule on which the enzyme acts.) enzymes are controlled by genes enzymes are grouped according to the reaction catalyzed enzymes require co-enzymes enzymes are affected by environmental factors, temperature, pH, etc. Most enzymes contain a protein part called an apoenzyme and a non-protein part called a coenzyme. Co-enzymes are usually vitamins or minerals. Definitions Metabolism - the total of all chemical reaction taking place in the body. Anabolism -synthesis reactions in the body. Catabolism - decomposition reactions in the body. EX. digestion When food is broken down during digestion, the base units must be absorbed through the lining of the small intestine: . 1. Amino acids pass directly into the bloodstream 2. Monosaccharides pass directly into the blood stream 3. Nucleotides pass directly into bloodstream. 4. Fats-are broken into fatty acids and glycerol. Since fats are not water soluble they must be dissolved in micelles (aggregates of bile salts) to be absorbed. The reactant in an enzyme reaction is a substrate. Every enzyme is specific in its actions and catalyzes only one reaction or one type of reaction EX : Peroxidase is an enzyme found in the liver. Peroxidase speeds up the breakdown of hydrogen peroxide, a waste product of cell metabolism that can be toxic in high concentrations. The breakdown that occurs is as follows: 2H2O2 -*- 2H20 + 02 Hydrogen Peroxide Water Peroxidase, or catalase, is an enzyme found in animals and plants, and in high concentration in the cells of the liver. Peroxidase has an active site that fits perfectly, like a lock and key, with hydrogen peroxide. Other examples of enzymes would be lipase, which only breaks down lipids; amylase, which only breaks down amylose; and lactase, which only breaks down lactose. When peroxidase, found in the liver, is exposed to hydrogen peroxide, large numbers of oxygen bubbles are produced, as well as water; therefore, a positive test for liver peroxidase will produce large numbers of oxygen bubbles when the liver is exposed to hydrogen peroxide. INORGANIC CHEMISTRY Inorganic compounds do not contain the element carbon. Metal salts, and pure elements are normally associated with inorganic analysis. As opposed to organic compounds, inorganic samples tend to be more persistent. That is, they are more stable and normally can be analyzed long after exposure. Napoleon Bonaparte died in 1821 in exile on the remote island of Saint Helena. Locks of his hair collected at the time of his death and handed down through generations of families as treasured heirlooms. Almost 140 years Napoleon's hair was analyzed and found to contain traces of the metal arsenic. This has led to speculation that he was poisoned in his last years. Thus inorganic compounds can be detected k after organic compounds have broken down. Napoleon Bonaparte Did forensic evidence prove that he was poisoned 140 yrs after his death??? Metals can be made up of pure samples of an element, or thev can be mixtures known as alloys. Even in the case of pure samples other elements are present in trace amounts. These trace elements often referred to as "invisible markers" since they can be used associate various fragments of metal with a single source. Bullets are made of the element lead; however, trace quantities of other metals such as silver can also be found in lead bullets. Antimony-also added in small amounts to the lead to make the bullet harder In the case of the assassination of President John F. Kennedy, the bullet fragments recovered from the president, Governor John Connally, and the presidential limousine were analyzed for the invisibility markers silver and antimony. Since the amounts of silver and antimony vary from bullet to bullet, this method could be used to determine how many bullets were involved. In this case the silver antimony concentrations were consistent with all the fragments coming from two bullets, which supported the findings of the Warren Commission. Did forensics prove there was not a second gunman on the grassy null?? Gunshot Residue Gunshot Residue (GSR) is expected to be found on the shooters hands and consists of Barium, Antimony and lead Classes of Inorganic Compounds: 1. Water-Most important and abundant inorganic compound a. Excellent solvent b. Participates in chemical reactions c. Absorbs and releases heat slowly d. Requires large amount of heat to change from a liquid to a gas. e. Serves as a lubricant 2. Acids-Compounds with one or more hydrogen (H ) ions and one or more anions(negative ions). , Their characteristics include: sour taste, they react with bases to form salts and water, and they turn litmus paper red. EX a. H2PO4 - phosphoric acid b. HNO3 - nitric acid c. H2SO4 - sulfuric acid d. H2CO3 - carbonic acid 3. Bases-Compounds with one or more cations (positive ions) and one or more hydroxyl ions (OH). They are characterized by having a bitter taste, being corrosive and turning litmus paper blue a. KOH - potassium hydroxide Read acid bath story pg 47 forensic CSI book ANALYTICAL vs QUALITATIVE CHEMISTRY: Analytical chemistry is the branch of chemistry involved in qualitatative and quantitative analysis. Qualitative analysis involves the identification of a compound. Quantitative analysis Quantitative analysis involves the determination of the amount of a substance present. The identity of a compound] sometimes used to establish whether a law has been broken white powder sent to the crime lab may contain cocaine, or it may contain pancake flour. It is up to the crime lab to determine the identity of the unknown chemical. The quantity also determines the crime. Gas Chromatography: The identification of chemicals is normally carried out by spectroscopy, which is the study of spectra (plural of spectrum). A spectrum is the orderly arrangement of a more complex phenomenon such as light, sound, or mass. White light is the combination of all the colors in the spectrum. It can be separated into its component colors by passing it through a prisms For forensic science, light and mass are the most important spectra because they can be used to identify chemicals. These spectra act as fingerprints and can be used in a court to prove the true identity of a material. Gas Chromatography: The problem with spectroscopy is that the sample must be a pure compound or else a positive identification cannot be made. spectra from a mixture of compounds is useless to a forensic investigator. Gas Chromatography: The problem of separating complicated mixtures of organic com1 pounds was simplified by the discovery of chromatography in 1903 by Mikhail Tswett. Tswett used a glass column filled with calcium carbonate (chalk) to separate the pigments in a leaf. Tswett called this process chromatography, which means color writing. Liquid chromatography (LC) is more difficult to set up but has advantage of operating at room temperature. Its use is normally restricted to compounds that decompose at the temperatures required for gas chromatography. Spectroscopy: For organic compounds the two most commonly used forms of identification are mass spectroscopy (MS) and infrared (IR) spectroscopy. Mass spectroscopy is the preferred method of analysis for organic samples A mass spectrometer smashes a compound into fragments and produces a mass spectrum of the compound and its fragments. This spectrum is unique for each compound and can be used to identify a chemical in court. An infrared spectrometer works by measuring the infrared light absorbed by a sample. Infrared light is lower in energy than visible light and allows infrared spectra to be used as fingerprints to identify chemical, but is very time consuming. Summary of Techniques The method of choice for the analysis of organic compounds is a gas chromatograph-mass spectrometer (GC/MS). The preferred method of analyzing inorganic samples or elements is atomic spectroscopy, which includes atomic absorption and atomic emission spectroscopy. TOXICOLOGY: The word toxicology comes from the Greek term toxon, which means "bow." The tips of bows were sometimes dipped in poison to make them more deadly. Forensic Toxicology Postmortem—medical examiner or coroner Criminal—motor vehicle accidents (MVA) Workplace—drug testing Sports—human and animal Environment—industrial, catastrophic, terrorism Chapter 8 Toxicology Toxic substances may: Be a cause of death Contribute to death Cause impairment Explain behavior Chapter 8 The Severity of the Problem “If all those buried in our cemeteries who were poisoned could raise their hands, we would probably be shocked by the numbers.” —John Harris Trestrail, “Criminal Poisoning” Chapter 8 People of Historical Significance Mathieu Orfila—known as the father of forensic toxicology, published in 1814 “Traite des Poisons” which described the first systematic approach to the study of the chemistry and physiological nature of poisons. Chapter 8 Aspects of Toxicity Dosage The chemical or physical form of the substance The mode of entry into the body Body weight and physiological conditions of the victim, including age and sex The time period of exposure The presence of other chemicals in the body or in the dose Chapter 8 Lethal Dose LD50—refers to the dose of a substance that kills half the test population, usually within four hours Expressed in milligrams of substance per kilogram of body weight Chapter 8 Toxicity Classes LD50 (rat,oral) Correlation to Ingestion by 150 lb Adult Human Toxicity <1mg/kg a taste to a drop extremely 1-50 mg/kg to a teaspoon highly 50-500 mg/kg to an ounce moderately 500-5000 mg/kg to a pint slightly 5-15 g/kg to a quart practically non-toxic Over 15g/kg more than 1 quart relatively harmless Chapter 8 Federal Regulatory Agencies Food and Drug Administration (FDA) Environmental Protection Agency (EPA) Consumer Product Safety Commission Department of Transportation (DOT) Occupational Safety and Health Administration (OSHA) Chapter 8 Symptoms of Various Types of Poisoning Type of Poison Caustic Poison (lye) Carbon Monoxide .. Sulfuric acid Hydrochloric acid Nitric acid Phosphorous Cyanide Arsenic, Mercury Methyl (wood) or Isopropyl (rubbing) alcohol Chapter 8 Symptom/Evidence Characteristic burns around the lips and mouth of the victim Red or pink patches on the chest and thighs, unusually bright red lividity remain in body . . Up to 6wks Black vomit Greenish-brown vomit Yellow vomit Coffee brown vomit. Onion or garlic odor Burnt almond odor Pronounced diarrhea Nausea and vomiting, unconsciousness, possibly blindness There is a suggestion that this mental affliction was attributable to mercury poisoning from his chemical experiments. Indeed, Newton was known to experiment widely in his laboratory with mercury. Mercury poisoning is associated with ‘. . . morbid irritability, insomnia, and mental hyperactivity’, all the features that Newton displayed throughout his life. Modern studies of Newton’s hair at Cambridge University showed high levels of mercury. Chapter 8 Beethoven Even if Beethoven was deaf, he 'listened' to his doctor. But this proved even worse, as his doctor poisoned him. With lead. A Viennese forensic expert shows that the composer's physician unwittingly overdosed the genius with the toxic metal. It was clear that the master had been very ill years before his death in 1827, at the age of 57. Previous analyses showed that Beethoven had experienced lead poisoning, with high levels of the toxin in his hair and bones. Chapter 8 Erratic behaviour A new study suggests that Lincoln's erratic behaviour may have been linked to the pills he took to treat his persistent "melancholia". The pills, known as blue mass, contained the metal mercury in potentially toxic doses that exceeded modern day safety limits by nearly 9,000 times. The researchers believe that this toxic effect may have had a profound impact on Lincoln's Chapter 8 mood. The former US president was famous for his patience. But earlier in life he was also prone to outbursts of uncontrollable rage. Carbon dioxide remains in the blood for up to 6 months after a person dies. Hydrogen sulfide smells like rotten eggs at low levels but at higher concentration, cannot be detected by smell and is quite lethal. Arsine is the hydride of arsenic and forms a colorless gas with an odor of garlic. Chlorine gas can also be very poisonous, but it is usually formed by accident when household chemicals such as bleach (sodium hypochlorite) and toilet bowl cleaner (hydrochloric acid) are mixed Hydrogen cyanide is formed when an acid reacts with a salt of cyanide. The resulting gas is very poisonous and smells of bitter almonds. Some pathologists can detect cyanide poisoning from the odor during the autopsy. About 50 mg of cyanide is considered a lethal dose. Cyanide works by inactivating the enzyme cytochrome oxidase and blocking the oxidation of glucose inside cells. The person dies in a matter of minutes. Critical Information on Poisons Form Common color Characteristic odor Solubility Taste Common sources Lethal dose Mechanism Possible methods of administration Time interval of onset of symptoms. Symptoms resulting from an acute exposure Symptoms resulting from chronic exposure Disease states mimicked by poisoning Notes relating to the victim Specimens from victim Analytical detection methods Known toxic levels Notes pertinent to analysis of poison List of cases in which poison was used —John Trestrail from “Criminal Poisoning” Chapter 8 To Prove a Case Prove a crime was committed Motive Intent Access to poison Access to victim Death was caused by poison Death was homicidal Chapter 8 Forensic Autopsy Look for: Irritated tissues Characteristic odors Mees lines—single transverse white bands on nails. Order toxicological screens Postmortem concentrations should be done at the scene for comparison No realistic calculation of dose can be made from a single measurement Chapter 8 Human Specimens for Analysis Blood Urine Vitreous Humor of Eyes Bile Gastric contents Chapter 8 Liver tissue Brain tissue Kidney tissue Hair/nails TOXICOLOGY: This is also where the tradition of toasting and touching wine goblets together to prove not deadlysubstance was present. Toxicology is the study of body fluids, tissue, and organs for the presence of drugs or poisons. A toxicologist must have a minimum of a baccalaureate degree, a master's degree, or a Ph.D. in the physical or biological sciences. At least 2 years of work in toxicology is normally required after graduation The time required to detect drugs using blood urine, saliva, or sweat varies from about 1 to 5 days. In the case of hair testing it takes about 5 days for a drug or its metabolites to appear in the hair, but its presence can be detected for 6 months or more. Many types of poisons can be present in a victim. There are many organic poisons, both naturally occurring (produced in nature) and synthetic (made in a laboratory). Organic poisons include alkaloids, barbiturates, glycosides, ricin, botulin, curare, and various venoms. Alkaloids are mtrogen-contammg coYcipoxx-n&s extracted from plants. Curare, an extract from the bark of the tree Strychnos toxifera, is an example of an alkaloid. Certain South American tribes prepared the poison by boiling the bark and a mixture of other ingredients for about 2 days. The solution was then strained and used in darts for blowguns to bring down birds or mammals. Curare causes the paralysis of skeletal muscles, which can lead to death by suffocation. The person is awake and aware of the paralysis until unconsciousness sets in. Strychnine is another related alkaloid that can be extracted from the tree Strychnos nux-vomica. Strychnine is a convulsive and causes the victim to suffer convulsions of all their voluntary muscles before death by asphyxia sets in. . Botulinal toxin, produced by the bacterium Clostridium botulinum, is the most toxic poison known. As little as 1 g of this toxin could kill 1 million people. Inorganic and metallic poisons include antimony, arsenic, barium, lead, mercury, phosphorus, and thallium. Poisoning by the heavy metals mercury and lead occurs when these metals react with enzymes in the body and inactivate them. Symptoms of heavy metal poisoning often include stomach pains, coma, and then death Lead poisoning: brain damage, found in paint, x-ray shielding old water pipes, lead gas factors that influence effects of poisoning in the body: 1. dose 2. form of entry 3. duration of exposure 4. weight LD50: kills at least 50% test population exposed to substance Drugs “Having sniffed the dead man’s lips, I detected a slightly sour smell, and I came to the conclusion that he had poison forced upon him.” —Sherlock Holmes, in Sir Arthur Conan Doyle’s A Study in Scarlet Drugs and Crime ® A drug is a natural or synthetic substance designed to affect the subject psychologically or physiologically. ® “Controlled substances” are drugs that are restricted by law ® Controlled Substances Act is a law that was enacted in 1970; it lists illegal drugs, their category and their penalty for possession, sale or use. Chapter 7 ILLEGAL DRUGS Illegal drugs and related materials are the largest class of physical evidence received by crime labs. The abuse of drugs can result in tolerance and dependency. The federal government keeps track of illegal drugs that are showing up in arrests on the street. The most used illegal drugs are listed in a threat matrix published by the National Drug Intelligence Center of the U.S. Department of Justice Nationally 37% of state and local police agencies identify cocaine as the major drug threat. Next are methamphetamine at 36%, marijuana at 13%, heroin at 9% State and local police agencies estimate that cocaine abuse contributes the most of violent crime, about 50% and to property crime about 42% The leaves of the coca plant are used to extract cocaine. Sigmund Freud Sigmund Freud considered cocaine a wonder drug an prescribed it to his patients. 1886 Coca Cola Company marketed its new soft drink, made from the same coca leaves ( it contained 60 mg of cocaine. In 1903 the company was forced to remove cocaine from its beverage, but it uses the leaves ( cocainefree) for flavor to this day. Cocaine mixed with an aqueous solution of baking soda and heated is called crack Methamphetamine in the powdered form is called crystal or crank, ice methamphetamine looks like tiny pieces of ice. Marijuana is the most commonly used illegal drug in the United States. Heroin is a narcotic ( meaning it reduces pain and causes sleep) and Morphine is the active ingredient of opium, the juice of the unripe poppy plant Wizard of Oz There is a famous scene in the Wizard of Oz where the witch says, Poppies will make them sleep referring to opium. Bayer In 1898 Bayer marketed a new wonder drug designed to cure all sorts of ailments. This wonder drug could be purchased at the local drug store by the name of Bayer Heroin. After heroin became illegal the Bayer switched to its next miracle drug, aspirin. Ecstasy is a hallucinogen that is synthetic and is in a group of club drugs. Pharmaceuticals are the class of abused substances that are available legally by prescription. Ex valium, Ritalin ect… Club drugs include GHB and Rohpnol which are tasteless and odorless, and can be slipped into a persons drink without their knowledge. Rohypnol can cause amnesia so the person may not remember the events that occurred when they were incapacitated. The first synthesized LSD was in 1943 from ergot fungus PCP can cause a feeling of invincibility to the user and many individuals find they have broken bones or torn tendons , muscles and ligaments while on PCP CONTROL SUBSTANCE ACT; 1970 Controlled substance act placed drugs in schedules and these drugs are called controlled substances and cannot be obtained legally without a prescription Controlled Substances Act ® Schedule I—high potential for abuse; no currently acceptable medical use in the US; a lack of accepted safety for use under medical supervision ® Schedule II—high potential for abuse; a currently accepted medical use with severe restrictions; abuse may lead to severe psychological or physical dependence ® Schedule III—lower potential for abuse than the drugs in I or II; a currently accepted medical use in the US; abuse may lead to moderate physical dependence or high psychological dependence ® Schedule IV—low potential for abuse relative to drugs in III; a currently accepted medical use in the US; abuse may lead to limited physical or psychological dependence relative to drugs in III ® Schedule V—low potential for abuse relative to drugs in IV; currently accepted medical use in the US; abuse may lead to limited physical or psychological dependence relative to drugs in IV Chapter 7 Examples of Controlled Substances and Their Schedule Placement ® Schedule I—heroin (diacetylmorphine), LSD, marijuana, ecstasy (MDMA) ® Schedule II—cocaine, morphine, amphetamines (including methamphetamines), PCP, Ritalin ® Schedule III—intermediate acting barbiturates, anabolic steroids, ketamine ® Schedule IV—other stimulants and depressants including Valium, Xanan, Librium, phenobarbital, Darvon ® Schedule V—codeine found in low doses in cough medicines Chapter 7 Human Components Used for Drug Analysis Chapter 7 ® Blood ® Liver tissue ® Urine ® Brain tissue ® Hair ® Kidney tissue ® Gastric Contents ® Spleen tissue ® Bile ® Vitreous Humor of the Eye ANALYSIS OF DRUG EVIDENCE: The collection of drug evidence must be done with care. Many drugs are so potent that they can cause an effect through inhalation or absorption through the skin. Drug analysis is done in two steps: 1. Presumptory test: first quick and easy screening to determine if a drug is probably present ( color test for drugs) 2. Confirmatory test: to positively prove the presence o f a drug Drug Identification Screening or presumptive tests ® Spot or color tests ® Microcrystalline test— a reagent is added that produces a crystalline precipitate which is unique for a certain drug. ® Chromatography Chapter 7 Confirmatory tests ® Spectrophotometry ® Ultraviolet (UV) ® Visible ® Infrared (IR) ® Mass spectrometry Presumptive Color Tests Marquis—turns purple in the presence of most opium derivatives and orange-brown with amphetamines Dillie-Koppanyi—turns violetblue in the presence of barbiturates Duquenois-Levine—turns a purple color in the presence of marijuana Van Urk—turns a blue-purple in the presence of LSD Scott test—color test for cocaine, blue Chapter 7 Presumptory test can yield false positive test, for this reason they cannot be used in court to positively prove the presence of a drug. Chromatography ®A technique for separating mixtures into their components ®Includes two phases—a mobile one that flows past a stationary one. ®The mixture interacts with the stationary phase and separates. Chapter 7 Types of Chromatography ®Paper ®Thin Layer (TLC) ®Gas (GC) ®Pyrolysis Gas (PGC) ®Liquid (LC) ®High Pressure Liquid (HPLC) ®Column Chapter 7 Paper Chromatography ® Stationary phase—paper ® Mobile phase—a liquid solvent Capillary action moves the mobile phase through the stationary phase Chapter 7 ALCOHOL: Considered a stimulant The limit for DWI has been set at the federal level at 0.08% The rate of absorption of alcohol by the human body is controlled by 4 factors: The quantity of alcohol consumption The time over which the alcohol was consumed form of the alcohol contents of the stomach The body eliminates alcohol by excretion and oxidation. ( about 5% alcohol leaves body unchanged in breath, sweat and urine) Excretion occurs by breathing, sweating, and urination, and oxidation occurs in the liver. The rate of elimination is constant and can be calculated by the formula Rate of elimination = 0.01 + 0.014(weight/300lb One drink is defined as: 10 oz to 12 oz beer at 4to 5% alcohol 8 to 12 oz wine cooler at 4 to 6 % alcohol 4 to 5 oz table wine 9 to 12 % alcohol 1.25 oz of 80 proof alcohol 1 oz 100 proof alcohol ) In the case of wine and beer: which don’t use proof the formula for rate of eleimation is: Ma = .23 x ounces of liquor x proof When alcohol enter the body, it dissolves in all body fluids, thus blood alcohol content (BAC) can be calculated with the following formula %BAC(g/100mL) = 0.10 x MA/(VD x MB) MA = mass of alcohol ( # grams of alcohol) = .11 x oz liquor x proof MB = body mass ( kg) = body weight/2.2 VD = volume of distribution (L/Kg) is 0.7 for men and .6 for women EXAMPLE: A 120 lo woman consumes 3 drinks each containing one shot of 80 proof vodka. What is her BAC? ( each mixed drink is assumed to contain 1 jigger of 1.5 oz vodka) Three drinks = 3 x 1.5 oz = 4.5 oz MA = .011 x oz of liquor x proof = .011 x 4.5 oz x 80 = 39.6 g VD = .6 L/kg ( woman) MB= 120 lb/2.2lb/kg = 55 kg %BAC(g/100mL) = 0.10 x MA/(VD x MB) = .10 x 39.6g/(.6L/kg x 55 kg) = 0.12% BREATHALYZER: The alcohol in a person’s blood is about 2100 times more concentrated than the alcohol in a person’s breath. This ratio is controlled by body temperature, so it is the same for each person. A breathalyzer measures the alcohol content of a person’s breath, multiplied it by 2100 and calculates the BAC