Intro to Forensic Science PDF

Intro to Forensic / science What people think when I say I'm going into Forensics. MB you mean uxe csi?! Oo A field of science...

Intro to Forensic / science What people think when I say I'm going into Forensics. MB you mean uxe csi?! Oo A field of science dedicated to the methodical gathering and analysis of evidence to establish facts that can be presented in a legal proceeding...)) GraphJem.com  A DAY IN THE LIFE OFA CS\i NOTES: = ee ra ENT/5> Collaberate with crime MEMOS: = scene investigators Handle crime = 8B scene evidence CouRT Bantss Testify in court Document findings Intro to Forensic Science Criminalistics the recognition, collection, identification, individualization, and interpretation of physical evidence, and the application of the natural sciences to law-science matters Forensic Sei the application of science to criminal and civil ciIeEnNCE laws that are enforced by police agencies in a criminal justice system Forensic science owes its origins to several individuals who developed the principles and techniques needed to identify or compare physical evidence. sir Arthur Conan Doyle ¢ Popularized crime-detection methods through Sherlock Holmes ¢ Sherlock Holmes applied the principles of: ° serology, ¢ fingerprinting, ¢ firearm identification, and * questioned-document examination Mathieu Orfila ¢ Father of forensic toxicology ¢ Spanish chemist who published the first scientific treatise on the detection of poisons and their effects on animals ¢ Called Traite des poisons Eugene Vidocq ¢ Was acriminal in France in the late 18" and early 19" centuries ¢ Founded the Brigade de la Sdrete ¢ Aplain-clothes investigative unit ¢ Utilized his perspective as a former criminal ¢ Advocated for the first major criminal database =a> ¢ Theorized that most crime was perpetrated by 2 vet : "* Ae] repeat offenders Seuvy “a a ¢ Following an arrest, the police would record a ian p cy suspect’s aliases, physical description, Pes former convictions, possible motive, and any Pree other relevant information. ; Alfonse Bertillon e Father of criminal identification « Researched biometrics ¢ The study of analyzing human body characteristics ¢ Developed a system using photographs and taking a series of body measurements as ameans of distinguishing individuals ¢ Known as anthropometry, signaletics, or bertillonage  ———_+ eieieie | Height 1m ZL. cf Head length | 47. L. Foot Case ae | Ae BEES botor L. Eve Eng. Het. Sat ieaa Width (47 L. Mid, F. Cee Apparent A. Out A. PS es with |ZFe? | 1. nit. F. Periph ale Tronk Loa R. Ear Igth. 6.2 L. Cubit Remarks relative to Measurements. 816 j | @ Bridge sce § Sup Bor?Z#tec-f Hair ¢ d = oO | yn yn = a Presence varies from individual to individual = S | | oe a and between hairs of a given individual = 2 Absent Globular Fragmental Ladder Aeroform The medullary index measures the diameter Can be absent, continuous, or discontinuous/ of the medulla relative to the diameter of fragmented. Animal hair has more structured the hair shaft. shapes. ° The medulla is generally Connective tissue of dermis + muscle and elements of vascular system O Endoderm > Organs e 4-8 weeks - Limb development o Arms, legs, knees, elbows, fingers, and toes can be seen in 2nd month © Hand changes from paddle to infant form with fingers and thumb @e 6 weeks - Palmar volar pads (interdigital > thenar > hypothenar) e 7-8 weeks - Fingertip volar pads (thumb - little finger) The Fingerprint Sourcebook 8 weeks @ 8 weeks - Basal cells begin consistently dividing to form intermediate cell layers | @ 8 weeks - Approx. 1 inch and 1 gram https://www.amazon.com/Spare-Balance-Weight-Stainless-Steel/dp/BO7D7IMHZ4 First Trimester Cont. @ 9-12 weeks - Nervous system develops, arms and legs begin to move e 10-10.5 weeks - Primary ridge formation (bottom of epidermis) oO. First visual evidence of interaction between the dermis and epidermis The Fingerprint Sourcebook. F eta | p ri ma ry ri d ges The Fingerprint Sourcebook. ’ Second Trimester @ 12-16 weeks - Friction ridges forming and maturing © Primary ridges mature, extend deeper into dermis @ 15 weeks - Entire volar surface covered in ridges @ 15-17 weeks - Secondary ridges @ 16 weeks - Volar pads are merged with contours of fingers, palms, and soles @ 16 weeks - Minutiae “ | The Fingerprint Sourcebook. @ 16 weeks - Sweat glands mature; sweat Fetal secondary ridges ducts and pores appear along epidermal ridges ’ Second Trimester Cont. @ 20 weeks - Arrangement of primary and secondary ridges continues until here @ 24 weeks - Maturation © Primary and secondary ridges are linked; molded to the dermis via papillae pegs. https://picjumbo.com/author/viktorhanacek/  PEAS Ne nt A te = ss ES LAN WSF INST) 5 AW A SSss2 Seo yt | cr See Di!’ ~ =e SE y WS \sif ig Ft sf thi - = eit Li 4 ‘ ily =. Ni. f “ | :* «} Pe t A \ hk ike oe Leer’ Le = ih 1h ‘'y y™ ¢ é " eh)F fima oe a } i cee Fe ail WAM as ¢, lt # he # aah a { it \" tf tal atae 2 fi a ‘ LT 1 \ Z MMS Zr fi : 4 Pet A a ne FH tiie - CS gt age of aK VAS ee Tee ity ~ fa ee a ES ». Ah a “: Laer ea h https://www.cabarruscounty.us/Government/Departments/Sheriffs-Office/Criminal-Investigations Comparison & Processing Comparison e Levels of detail e Pattern types e ACE-V Level 1 detail Overall ridge flow, pattern types  LENN Loops ¢ Most common (~60%) ¢ Right/left loop OR ulnar/radial loop ¢ One delta Arches e Least common pattern type (~5%) ¢ No deltas Whorls (~35%) ¢ Two deltas ¢ Plain & central pocket loop have at least on ridge that makes a complete circuit. ¢ Double loop — two loops e Accidental — two or more pattern types or irregular  ® Bifurcation Gree » Ridge Ending Level 2 detail * Enclosure Ridge path, minutiae * Short Ridge W : A.s * Dot ‘ Level 3 detail Ridge and pore shapes, incipient ridges, scars, etc. ’ Examination Process — ACE-V Analysis Comparison —E Evaluation Verification Analysis ° Latent print is assessed for value by observing things like pattern type, ridge flow (level 1 details), making note of any distortion, and marking specific minutiae (level 2 details). Orientation and anatomical source may be determined during this stage. * ~Adecision as to whether the print is suitable for comparison is made. Comparison If the print is suitable, the comparison process involves the selection of a target group of details in the unknown print which is then searched for in the known prints side-by-side. If the target group is found, a more in-depth search occurs to see if there is additional correspondence or any disagreement. Comparison “Imagine trying to put together a 1000-piece jigsaw puzzle, but you only have 100 pieces, and you don’t know what the picture is supposed to look like.” Imagine searching for this In here...plus the other hand...and then add on five more people... Evaluation ¢ The information gathered during comparison allows for a conclusion of identification, exclusion, or inconclusive to be made. Verification ¢ Asecond qualified examiner performs an independent ACE in order to verify all conclusions and ensure that the previous analysis and comparisons were given proper consideration. 12 11 10 9 12 11 10 Processing Types of surfaces Chemical processing Preservation Digital Imaging Deposition Factors ¢ Pre-transfer conditions ¢ Condition of skin ¢ Transfer conditions - Surface texture/material, curvature, contaminants ¢ Deposition pressure, movement, multiple touches ¢ Post-transfer conditions - Exposure to elements ¢ Improper packaging  ¢ Absorbs water ¢ Ex: raw wood, paper ¢ Does not absorb water ¢ Ex: tile, glass, metal, plastic Types of Su rfa ces ¢ Some residue stays on the surface, some absorbs ¢ Ex: coated cardboards, magazines ¢ Mostly tape ’ Porous Surfaces Latent print residue soaks into the surface Examples: Paper, cardboard, raw wood Chemical treatment lodine, Indanedione (IND), Ninhydrin, Oil Red O The most common component that is targeted — Amino Acids IND and/or Ninhydrin Items are either sprayed, dipped, or the chemical is painted on After air drying, items are typically placed in a humidity chamber (~5-10 minutes) and/or allowed to process naturally for a few days Developed prints are viewed using the laser for IND and ambient light for Ninhydrin and then photographed Capable of developing very old latent print residue Humidity Chamber  Indanedione ~ Bria wt ty or om wimegnerts.* atm Ninhy r Oil Red O ’ Non-Porous Surfaces ¢ Latent print residue tends to stay on the surface e Items are typically fumed with cyanoacrylate (superglue) then stained with a fluorescent dye stain and/or powdered ¢ Superglue developed prints are sometimes visible after fuming, the dye stains are typically used after to dramatically increase contrast ¢ When fluorescent dye stain is used, the item is then viewed with the laser ¢ Developed latent prints are typically photographed and sometimes lifted if powder was used ’ Superglue tanks Super glue is placed on a foil dish and heated. Super glue developed print Rhodami ne 6G ’ Adhesives Typically have a sticky side and non-sticky side Non-sticky side is usually addressed first by following the above mentioned porous/non-porous processing Most tapes that are processed tend to be non-porous like duct tape, packing tape, and electrical tape Canned air and/or chemicals can be used to separate tape layers but may be time consuming Sticky side powder/WetWop is commonly used to process the adhesive side or stains like gentian violet can be used ’ Ad hesives Gentian Violet White Wetwop Sticky Side Powder ’ Possible Blood ¢ Porous surfaces ¢ The blood and/or latent residue soaks into the surface ¢ IND and Ninhydrin ¢ Non-Porous ¢ Blood dries on the surface of the evidence ¢ Stains can be used to further develop the impressions by targeting components such as proteins ¢ Amido Black * sensitive chemical, develops prints that are commonly not visible to the naked eye ¢ Acid Yellow 7 ¢ Used with a blue light source Acid Yellow 7 used on blood prints and fluoresced with a blue light source H AAT ia AUANONANLUEELLU TAU METRIC 4} 2 t—} 1. = Amido Black developed blood footprint on floor Case Example  or ~ os 60Sfr # W3Ll 9 8 ’ Digital Image Processing e “We are not in the business of creating detail. We are in the business of optimizing the signal-to-noise ratio, meaning that we can only make an effort to clarify image information that is already present in the digital image, while suppressing any noise that may be visually distracting to the greatest degree possible.” ¢ Forensic Digital Image Processing CRC Press 2018 Brian Dalrymple and Jill Smith Ch. 6 pg. 164 ¢ Digital Image Management System ’ Digital Image Processing ’ Digital Imaging Digital Image Processing 7 i wFe be iy: a ; soe Nak i a —_ =  t Gee 4h, — * hs al a: i > if es s a a a + ae. wa gee. Ft +\. = ae Pa és #7, ye ra a tI * & o led wR gen * an... “ae. eS 2 " + # a. wa " Seta ti Pers: *s % so. '. a =. a ae a -™ a < pes oe Fite = - 2 e- “ F 3F° W.2¢ we — iat - =. : EP re s =z the column. ; cw * ++ Detector After a mixture has traversed the Hoh Li sun stately sana length of the column, it will emerge separated into its components. The time required fora component - | to emerge from a GC column is ee ile known as retention time. The 1 thal k i written record of this separation is called a chromatogram.  Wa (7 GC = 1. Sample 2. Injector 4. Column jr A sample is introduced by a syringe (1) :— {I io into a heated injection chamber (2). A constant stream of carrier gas (3) Arn Tr 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; 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 of elution identifies the component present, and the peak area identifies the concentration.  (a) An unknown mixture of barbiturates is identified by comparing its retention times to Pentobarbital Secobarbital (b) a Known mixture of —\ barbiturates. MASS SPECTROMETRY In the mass spectrometer, a beam of high-energy electrons collide with a material, producing positively charged ions. These positive ions almost instantaneously decompose into numerous fragments, which are separated according to their masses. The unique feature of mass spectrometry is that under carefully controlled conditions, no two substances produce the same fragmentation pattern. GAS CHROMATOGRAPH/ MASS SPECTROMETER (GC/MS) Two instruments connected together: ¢ GC — separates components a mixture. ¢ MS — fragments each component by high-energy electrons to produce a distinct pattern that 's | s unique and reproducible. -| cia Abunda a abo 600" 6 5 2 60 O = ay eke 3 wo y = 40 | Molecular Weight: 303 207 1100000 O74 I ju | l ‘e00000} | T T T T T 1 \ | o 50 100 150 200 250 300 350 eooval Ha 400000 | | || 4 | | 68 152 303 shelby I. stay, 192140 18 J 190 | 207 222000 244 250 [ane nie» 30 40 80 6) 70 BO Bo 160 140 120 440 140 150 160 170 160 190 200 210 280 280" 240 280 260 270 260 240 300 310 GAS CHROMATOGRAPH/ MASS SPECTROMETER (GC/MS) The sample is extracted and dissolved in an organic solvent. A small amount of the substance is injected into a heated inlet port, and a carrier gas sweeps it into the column. The GC column separates the mixture into its components. In the ion source, a filament wire emits electrons that strike the sample molecules, causing them to fragment as they leave the GC column.  GAS CHROMATOGRAPH/ MASS SPECTROMETER (GC/MS) The quadrupole, consisting of four rods, separates the fragments according to their mass (retention time). The detector counts the fragments passing through the ] “= quadrupole. The signal is small __.. Molecular Weight: 308. and must be amplified. “| | The data system detects and | «|e “ | measures the abundance of a 7 | i a Ho wel | |. ros DUC EL HOON be Wh ret] Bt each fragment and displays the mass spectrum. GAS CHROMATOGRAPH/ MASS SPECTROMETER (GC/MS) File \MSDCHEM\1\DATA\JUNE\ 11\METHAMPHETAMINESTD.D 1EM\ 1 \DATA\JUN \28\AMP.D \ND CRIME LAB Operator BPS GARLAND CRIME LAB using AcqMethod LOWw.M Acquired 14 Jun 2007 16:03 using AcqMethod LOW.M Instrument Instrument # 64 Sample Name: METHAMPHETAMINE (DL) STD SIGMA LOT # 50H02161 Info : Misc Info : BASE TO CHC13 1 Number: 17 Vial Number: 11 Wouncance TIC: AMP, Oidata ma (Abundance ~TG: METHAMPHETAMINESTD Didata.me r 1200000} 4400000) soacoa| ‘*10ac00 Date Verified: a2slor | | Reference Source: Mills 2° Edition y200c00) AMPHETAMINE feoacen! e: M2 initiats: 7 000000 50, Molecular Wei ght: 135 METHAMPHETAMINE aooo90: Molecular Weight: 148 7OS000+ 600000 BO0000 | 500000. 400000 300000 200000 700000 | epee ey peerpererps cee t T T re eee PT T T Time. 1 1200 14.00 {Tirnas—> 4.00 600 600 7.00 8.00 9.00 10.00 11.00 12:00 13.00 14.00 15.00 16.00 17.00 18.00 18.00 Abundance WO AMP Dudata.ms. Abundance ‘Scan 708 (6.061 min): METHAMPHETAMINESTO. Didata ms. Boo00a aa 200000 300000 | | zocoun- 700000. a a 65 [ar a a TT Tre WF sa0 1% THryrerepertrprrery 134 taeda a 86 6B 80 96 98 100 105 110 115 120 125 130 134 130 135 140 $5_60 65, 70 75 80 6 E.) 95 100 105 110 195 120 125 130 135 140 145 150 155 GAS CHROMATOGRAPH/ MASS SPECTROMETER (GC/MS) INFRARED ) SPECTROPHOTOMETER 7 (IR) The IR is an instrument used to measure and record the absorption spectrum of a chemical substance in the infrared (IR) region. Different materials have distinctively different infrared spectra; therefore, each IR spectrum is equivalent to a “fingerprint” of that substance. ¢ Bonds of molecules bend, stretch, and vibrate at certain frequencies. ¢ IR light is transmitted through a sample and when the light frequency matches frequency of the motion, the light is absorbed. FTIR-ATR Fourier Transform Infrared — Attenuated Total Reflectance ¢ The ATR enables samples to be examined directly in the solid without further preparation. ¢ IR radiation travels through the crystal and interacts with the sample on the surface in contact with the ATR crystal. Fast, confirmatory examination. ¢ Can conclusively identify substances. ¢ Can even differentiate between isomers. Drawback is you have to have a pure sample.  IR SPECTROPHOTOMETER BRUKER #138 01/08/2013 (DD/MM/YYYY) BRUKER #138 01/08/2013 (DDIMMIYYYY) ATTENUATED TOTAL REFLECTANCE 10:16:47 AM ATTENUATED TOTAL REFLECTANCE 12:15:17 PM Pseudoephedrine HCI Aldrich Lot 05307HA ATR platinum Diamond 1 Refl Ephedrine Hydrochloride Sigma Lot 37H3726 ATR platinum Diamond 1 Refl ner 95 fA | fy\| | 90 85 Transmittance [%] 80 75 70 65 60 3500 3000 2500 2000 1500 1000 500 3500 3000 2500 2000 1500 1000 500 Wavenumber cm-1 Wavenumber cm-1 OH  FTIR VS ATR 100 Jmninct\y Mon sp 25 10:47:59 2007 (GM 05:00) |W aH \ NE SID SIGMA-ALDRICHf LO |p ALN S9H03 | 164 95 METHANPHETAM DIRECT IN Kér | | II 90 85 Transmittance [%] 236Transmit-anca 75 7080 Methamphetamine-ATR | | 65 Methamphetamine-FTIR | 2000 1500 4200 60 Wavenumbers (1-1) 3500 3000 2500 2000 1500 1000 500 Wavenumber cm-1 Wed Jul 11 09:88:48 2007 (GMT-C5.90) PEN, 70-] Gamm= Hydroxy Butyric Acid \ | \ Oven Dried - Direct, in KBr 90 Date Venitied: 7/18/07 / | n Es ls Ard Feition Page: 1545 Initals: ye al | 80 Transmittance [%] 70 %eTransmittance 60 50 40 GHB-ATR 30 GHB-FTIR |. 3000 2000 00 1000 3500 3000 2500 2000 1500 1000 500 WWavenumbers (em-1) Wavenumber cm-1 HIGH PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC) UV-VIS/PDA A solvent containing the sample passes through a column. The components of the sample interact with the column differently. After the components are separated, the signal generated by the detector (UV-Vis/PDA) for each analyte, is compared to standards/published data. cy | i Technique is used for quantitative analysis. ¢ The presence of the analyte gives a response proportional to the concentration. HIGH PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC) MASS SPECTROMETRY ¢ Used for: ¢ Complex mixtures that cannot be separated on GCMS. ¢ Samples that are temperature sensitive. ¢ Quantitation. RAMAN SPECTROSCOPY Raman spectroscopy can provide rapid, sensitive, non-destructive analysis of a variety of drug types. Raman spectroscopy is based on the interaction of light with the chemical bonds of a substance. Observation of the scattered light that is absorbed at one frequency and emitted at a different frequency yields information about chemical structure, polymorphism, crystallinity and molecular dynamics.  RAMAN SPECTROSCOPY $...cthamphetamine HC! (PLA Bag) = Sigma (Lot# 24C-0710) ~ 2200 ‘Cocaine HC! (PLA Bag) - Sigma (Lot# SLBQ9338V) Thermo Scientific DXR2 Smart Raman - Instrument #203 Thu Jan 09 14:42:43 2020 (GMT-06:00) 2100: Thermo Scientific DXR2 Smart Raman - Instrument #203 Exposure time: 10.00 sec Thu Jan 09 14:30:40 2020 (GMT-06:00) Number of exposures: 2 Exposure time: 7.00 sec Number of background exposures: 2 Number of exposures: 2 Laser: 785 nm 1900: Number of background exposures: 2 Grating: 400 lines/mm Laser: 785 nm Spectrograph aperture: 50 pm slit 1800: Grating: 400 lines/mm Gr Laser power level: 100.0 mW ‘Spectrograph aperture: 50 ym slit 2400. 1700. Laser power level: 100.0 mW 1600 Methamphetamine 2200. 1500 Cocaine 2000. 1400 1800: Raman Intensity Raman Intensity 1600 1200 I 1000 | i | I, | | | | | | twih \ Nil —— lh‘al |ht JL — 1500 1000 500 WW i IW iN ri Ul iy Raman shift (cm-1) 1000 500 Numberof Fentanyl Results Count Collin Co — 312 [7 1 - 22 Gl 22 - 73 Cooke Co — 5 Ml 73 - 130 MMM 130 - 210 Dallas Co — 334 Mmm 210 - 340 Denton Co - 211 Grayson Co — 47 Rockwall Co — 34 Tarrant Co — 89 Numberof Heroin Results Count Collin Co — 304 im 1 - 31 Gi 31 - 100 Cooke Co -8 Mi 100 - 170 Mim 170 - 310 Dallas Co — 1,197 Mim 310 - 1,200 Denton Co — 332 Grayson Co — 78 Rockwall Co — 57 Tarrant Co — 92 Number of Cocaine Results Count iy 1 - 190 Collin Co — 748 i 190 - 590 Hi 590 - 1,000 Cooke Co — 39 Mm 1,000 - 2,000 Mim 2,000 - 3,200 Dallas Co — 2,232 Denton Co — 938 Grayson Co — 162 Rockwall Co — 169 Tarrant Co — 239 Number of Methamphetamine Results Count Collin Co — 2,323 [i 1 - 290 lll 290 - 910 Cooke Co — 496 MH 910 - 1,600 MMH 1,600 - 2,700 Dallas Co — 6,837 Mmm 2,700 - 6,900 Denton Co — 2,997 Grayson Co — 1,697 Rockwall Co — 662 Tarrant Co — 1,557 Collin Co — 15 Cooke Co — 0 Dallas Co — 40 Denton Co - 31 Grayson Co — 3 Rockwall Co — 4 Tarrant Co — 12 Number of Benzodiazepine Results Count (i) 1-16 Collin Co — 149 Gl 16-45 Wm 45 - 100 Cooke Co — 3 Mmm 100-150 Mmm 150 - 350 Dallas Co — 163 Denton Co - 34 Grayson Co — 19 Rockwall Co — 18 Tarrant Co — 20 Number of Marihuana Results Count Me 1-33 Collin Co — 73 i 33 - 85 Ml 85 - 160 Cooke Co - 13 Mi 160 - 230 Mim230 - 470 Dallas Co — 461 Denton Co — 220 Grayson Co — 58 Rockwall Co — 58 Tarrant Co — 46 Number of THC Results Count Ga 1 - 120 GH 120 - 350 Ml 350 - 870 MM 870 - 1,200 Mmm 1,200 - 2,500 Rockwall Co — 18 Tarrant Co — 25  TOP 10 RESULTS 01/01/2022 — 12/12/2023 & 01-01-2024 — 08-31-24 DRAFT COMPLETED AND RELEASED io. #of Cases 2022/2023 1.14 2.33 Percentage 0.74 6.18 2022/2023 36g 247 110920 247 ——_—, SS 577 3.88 \ oN m/ @ Methamphetamine Cocaine @ Methamphetamine HCl = Methamphetamine = Cocaine = Methamphetamine HCl @ Fentany! @ Heroin @ Marihuana Contains = Fentanyl = Heroin = Marihuana Contains @ Psilocin W@ delta-9-THC Above 1 @ Phencyclidine = Psilocin = delta-9-THC Above 1 = Phencyclidine @ Tetrahydrocannabinol(s) g Others = Tetrahydrocannabinol(s) = Others | Hof Cases 52 9024 ise. 151 Percentage 2024 7 g Methamphetamine @ Cocaine lm Fentanyl = Methamphetamine = Cocaine = Fentanyl = Methamphetamine HC! m delta-9-THC Above 1m Marihuana Contains = Methamphetamine HCI = delta-9-THC Above 1 = Marihuana Contains @ Psilocin @ Heroin g Phencyclidine ® Psilocin = Heroin = Phencyclidine @ Fluorofentanyl = Fluorofentanyl ® Others QUESTIONS? Introduction Toxicologists work to detect and identify the presence of drugs and poisons in body fluids, tissues, and organs. Toxicologists work in crime laboratories, medical examiners’ offices, hospital laboratories, and health facilities to identity a drug overdose and/or monitor the intake of drugs. A major branch of forensic toxicology deals with the measurement of alcohol in the body for matters that pertain to violations of criminal law. Toxicology of Alcohol The analysis of alcohol is the most common test in forensic toxicology. Alcohol, or ethyl alcohol, is a colorless liquid normally diluted with water and consumed as a beverage. As a depressant, alcohol principally effects the central nervous system - particularly the brain. Effects of Alcohol Mental Physical Relaxation ¢ Balance, speech, vision, Decreased inhibitions hearing Reasoning and memory ¢ Reduced reaction time Reduced judgement ¢ Gross motor impairment ¢ Ability to multi-task is reduced Alcohol and the Law Between 1939 and 1964, a person having a blood-alcohol level greater than 0.15 percent w/v was to be considered under the influence. «Lowered to 0.10 percent by 1965 In 1972 the impairment level was recommended to be lowered to 0.08 percent w/v. ¢ The ability to operate a vehicle in ALL individuals is affected at 0.08. Alcohol and the Law Starting in 2003, states that did not adopt the 0.08 percent level lost part of their federal funding for highway construction. To prevent a person’s refusal to take a test for alcohol consumption, the National Highway Traffic Safety Administration recommended an “implied consent” law. ¢ This law states that the operation of a motor vehicle on a public highway automatically carries with it the stipulation that a driver will submit tor a test for alcohol intoxication if requested or be subject to loss of the license. Alcohol Level Texas Penal Code: Sec. 49.04. DRIVING WHILE INTOXICATED. (a) A person commits an offense if the person is intoxicated while operating a motor vehicle in a public place. The extent an individual may be intoxicated is usually determined by either measuring the quantity of alcohol present in the blood system or by measuring the alcohol content in the breath. Alcohol Physiology ¢ Absorption ¢ Distribution ¢ Metabolism ¢ Elimination Alcohol Absorption Alcohol appears in the blood within minutes after it has been consumed and slowly increases concentration while being absorbed from the stomach (10-20%) and the small intestine (80-90%) into the bloodstream. For an average human drinking on an empty to modestly full stomach, alcohol is absorbed entirely into the blood stream 30-90 minutes after the completion of drinking. ¢ When drinking on a full stomach, the absorption time can be as long as 2-4 hours. Factors such as time taken to consume the drink, the alcohol content, the amount consumed, and food present in the stomach determine the rate at which alcohol is absorbed. Alcohol Distribution Humans have a closed circulatory system consisting of a heart, arteries, veins, and capillaries. Once alcohol is absorbed, it circulates in the blood throughout the body. Ethanol is hydrophilic. It moves into muscles and organs, but not into adipose tissue or bone. The volume of distribution is based on size, gender, and body mass index. Alcohol Metabolism When all the alcohol ha s been absorbed, a maximum alcohol level is reached in th e blood and the post-absorption period begins. Alcohol is metabolized in the stomach by alcohol dehydrogenase. Alcohol is then carried fo the liver where the process of its destruction starts. The picgho! concentration slowly decreases until a zero level is reached. Alcohol Elimination The elimination of alcohol throughout the body is accomplished through oxidation and excretion. ¢ Oxidation takes place almost entirely in the liver, ~97% of alcohol is eliminated through the breakdown into its metabolites via ADH. ¢ ~2% of alcohol is excreted unchanged in the breath, urine, and perspiration. In the lungs, carbon dioxide and alcohol leave the lood and oxygen enters the blood in the air sacs known as alveoli. Then, carbon dioxide and alcohol are exhaled during breathing. The rate of elimination is constant. ¢ The elimination or “burn-off” rate of alcohol varies, but the average is 0.015% per hour. Blood Alcohol ax Concentration (BAC) \ The Widemark equation is used to ““ynozot regularbeer \ = ™~ «8-9flozot maltliquor _~ = tablewine sSflazof —_-—=—«.SMozshotol ™ 80-proof spirits determine the impact of a drink to a... var nioe 2 vodka, tequl, person's BAC (based on type of beverage, weight, and gender). —— ig dL es BAC % = (A x 5.1 A/\W x r) - 01 5 x H about 5% about 7% about 12% about 40% alcohol alcohol alcohol alcohol A: Total alcohol consumed (ounces) The pescent of “pure” alcohol, expressed here as alcoho! by volume (aic/vol), varies by beverage W: Body weight (pounds) r: Alcohol distribution ratio - 0.73 for men, 0.66 for women H: Time passed since drinking (hours) Standard Field Sobriety Tests Law enforcement officers typically use field sobriety tests to estimate a motorist’s degree of physical impairment by alcohol and whether an evidential test for alcohol is justified. The horizontal gaze nystagmus test, walk and turn, and the one-leg stand are all considered reliable and effective psychophysical tests. Field Testing A portable, handheld, roadside breath tester may be used to determine a preliminary breath- alcohol content. The amount of alcohol exhaled in the breath is in direct proportion to the blood concentration. BrAC is reported as grams of alcohol per 210 liters of expired air (g/210L}.  Breath Breath inlet outlet || Digital display and printout Detector Infrared Sample chamber Filter radiation source Breath testers that operate on the principle of infrared light absorption are popular within the law enforcement community. Breath Teste rs Many types of breath testers are designed to capture a set volume of breath. The captured breath is exposed to infrared light. Breath Testers Breath testers operate on the fact that at 34°C, the ratio of alcohol in the blood to alcohol in alveolar breath is approximately 2,100 to 1. It's the degree of the interaction of the infrared light with alcohol in the breath chamber that allows the instrument to measure a blood alcohol concentration in breath. Some breath testing devices also use fuel cells. Blood Alcohol Testing Blood must always be drawn under medically accepted conditions by a qualified individual. A non-alcoholic disinfectant is applied before the suspect's skin is penetrated with a sterile needle or lancet. Once blood is removed from an individual, it is preserved sealed in an airtight container with an anticoagulant and a preservative and stored in a refrigerator. Gas Chromatography ™= \ Flame lonization (GC-FID) ; Sample: 1541 1. Ethylene glycol 02% 2. Methy! alcohol 1O% Gas chromatography is the 4 Isopropyl lcohol 0.4% 3. Ethyl alcohol 04% most widely used approach for 67, tert-Butyl alcohol 0.4% 5 n-Propyl alcohol «=O. 4% 80C-Buty! alcohol 0.4% determining alcohol levels in 23 8 r-Buty! alcohol 0.4% blood. 4 we o- 5 a Gas Chromatography.- Flame lonization (GC-FID) Dual Column Headspace Gas = » Chromatography - Flame lonization Detection ¢ Vial is sealed and heated. | \ = ¢ Volatile components diffuse into | the gas phase until the headspace has reached a state of volatile S equilibrium. at ¢ The sample is then taken from i | the headspace. G = the gas phase (headspace) ¢ Clean, efficient analysis. S = the sample phase Retrograde Extrapolation Retrograde extrapolation uses a defendant's blood alcohol concentration (BAC) obtained at a later time to estimate what their BAC was at an earlier time, based on the average rate at which alcohol is eliminated from the body. Role of the Toxicologist In addition to alcohol, the toxicologist is requested to examine body fluids and/or organs for the presence of various drugs and poisons. Without supportive evidence (the victim's symptoms, a postmortem examination, or the victim's personal effects), the toxicologist must use general screening procedures with the hope of narrowing thousands of possibilities to one. Role of the Toxicologist The toxicologist does not deal with drugs at the concentration levels found in powders and pills. ¢ Have been dissipated and distributed throughout the body The body is an “active chemistry laboratory.” ¢ Few substances enter and completely leave the body in the same chemical state. The toxicologist must assess the toxicity of the drug or poison. Types of Toxicology Cases DWI/DUI ° >90% of the cases received in the lab Sexual assault ¢ Both blood and urine analyzed for alcohol Questioned death (or any deceased subject testing) ¢ Vitreous is best for alcohol testing ¢ Blood from arm or femoral artery for drug content Homicide Child endangerment. _ ¢ Usually réceive blood for suspects and urine for victims The Analytical Scheme The forensic toxicologist devises an analytical scheme that will successfully detect, isolate, and identify foxic drug substances. Once the drug has been extracted trom the appropriate biological fluid, tissue, and/or organ, the forensic toxicologist proceeds to identity the drug substance present. Drug extraction is generally based on most drugs being either acidic or basic. The strategy used for identifying abused drugs entails a two-step approach: screening and confirmation. Screening A screening test is employed to provide the analyst with a quick likelihood that a specimen contains a drug substance. Positive results arising from a screening test are tentative and must be verified with a confirmation test. The most widely used screening tests are thin-layer chromatography, gas chromatography, and immunoassay. Enzyme Multiplied > Immunoassay Technique X (EMIT) Drug content analysis only requests, or both alcohol and drug analysis where alcohol was males Oo 48,XXXY;49, XXXXY; 50, XXXXXY > males 45, XO (Turner syndrome) > females 47, XXX (triple-X karyotype) > ‘normal’ female 47, XYY karyotype > ‘normal’ male Sex Reversed Humans fe) XY > female (Y minus TDF - testis determining factor) O XX > male (X plus TDF)  Forensic scientists can also type STRs located on the Y chromosome. More than 20 different Y-STR markers Y- S Ty Rs bawra ner Ielamifiled] Y-STR analysis will have only one peak, compared to autosomal-STR analysis, which Is derived from two chromosomes and has two peaks.  PAR1 a Yu “| _- pys393 5] DYs456 p 7 __— AMEL Y Y-STRs centromere 10 “I—— pys458 |—__ }———__DYS19 DYs391 DYS635 DYS437 + DYS439 The pseudoautosomal regions (PARs), q 15-]___ nys390 DYS389I/II located in the telomeric regions of the -|—— GATA-H4 _DYS438 chromosome, pair and recombine with 20 | ieetogeraee ¢ nits of NADI on Stas L 1 * Known as HV1 and HV2. \A tRNATY Subunits of y HV1 and HV2 are found to be highly variable —~ \e and are sequenced to determine the order of ‘Tha alle base pairs. Subunits of ATP syrthase  Mitochondrial DNA Testing Mitochondrial DNA typing does not approach STR analysis in its discrimination power. * mtDNA ts inherited from the mother. ¢ Individuals of the same maternal lineage will be indistinguishable by mtDNA analysis. Mitochondrial DNA Testing nucleus mtDNA is best for samples, such as hair, where STR analysis may not be possible. It is more rigorous, time consuming, and costly compared to nuclear DNA analysis. Mitochondrial DNA vs. Nuclear DNA Forens Ic DNA Analysis  Two young girls were raped and murdered in the Enderby area of Leicester. A man who had been arrested confessed to one murder but not the other. Police decided to use genetic profiling, but he was found to be First DNA innocent of both. The hunt was on to find a genetic Profiling Case profile among the entire male population of the area that matched samples taken trom the two victims. No match was found, until Colin Pitchtork was overheard boasting of how he had persuaded a friend to give a sample on his behalf. DNA from Pitchfork found him guilty. * The biological material used to develop a DNA profile include blood, semen, saliva, urine, feces, hair, teeth, bone, tissue, and cells. Biological Evidence The analysis and comparison of DNA evidence is typically conducted in the following types of cases: ¢ Sexual Assaults ¢ Assaults ¢ Homicides ¢ Burglaries ¢ Robberies ¢ Missing Persons ¢ Unidentified Remains Isolation of DNA ¢ Evidence is screened for biological stains ¢ Stains are cut out, swabbed, or collected whole ¢ Cuttings and swabs are stored frozen until DNA analysis is performed. ¢ The remainder of the evidence is retained frozen for further testing, if necessary. Reference Samples ¢ To compare the victim’s and/or the suspect's DNA profile to the recovered crime scene DNA, the laboratory will need to have known samples. * Reference samples are often collected by swabbing the inside of the cheek (buccal swabs). DNA Testing Once biological material is found on the evidence, DNA samples undergo the following process: 1. Extraction - the process of releasing the DNA from the cell 2. Quantification - the process of determining how much DNA is present 3. Amplification - the process of producing multiple copies of the DNA to characterize it 4 Electrophoresis - the process of separating amplified DNA product to permit identification Analysis and Interpretation - the process of quantitatively and qualitatively comparing DNA evidence samples to known DNA profiles; calculating statistics. Quality Assurance - the process of reviewing analyst reports for technical accuracy. 1. DNA Extraction DNA Extraction ¢ DNA extraction is a chemical process by which DNA is released from cells. ¢ Other cellular components are removed leaving a pure sample of DNA in an aqueous solution.  DNA Extraction Extraction methods follow the same basic procedure: ¢ The cell and nuclear membranes need to When a sample (such as blood or saliva) be broken up to allow the DNA to be free in is obtained, the DNA is only a small part solution. of what is present in the sample. Before ¢ Once the DNA is free, it can be separated the DNA can be analyzed, it must be from all other cellular components. extracted from the cells and purified. e After the DNA has been separated in solution, the remaining cellular debris can be removed and discarded, leaving only the DNA.  DNA Extraction ¢ The most common methods of DNA extraction include organic extraction (also called phenol chloroform: isoamyl alcohol), solid phase extraction, magnetic beads, and silica column. ¢ Differential extraction is a modified version of extraction in which the DNA from two different types of cells can be separated from each other before being purified from the solution.  ¢ The purpose of extraction is to purity the DNA sample by clearing away cellular material and proteins and to remove PCR inhibitors. * Reagents used during extraction include: * Proteinase K - breaks apart peptide bonds and digests nucleases DNA Extraction * Deterg ent (e.g. SDS) s - disrupts cell and organelle membranes ¢ Dithiothreitol (DTT) - disrupts disulfide bonds in protein cell structures and digests sperm cells  Organic extraction is a conventional method that uses organic chemicals to isolate genomic DNA. The procedure can be described in four steps: D NA Extra cti @) ni 1. Solubilization of the stain components 2. Denaturation and hydrolysis of proteins 3. Removal of denatured proteins 4. Purification of DNA ORGANIC EXTRACTION of DNA Aqueous. Phase ONA interface 7 Degraded Organic > protein& Phase | Cell debris -  Sample Product DNA Extraction Lyse Using Filtration ¢ Nucleic acids are attracted to the silica |... Bind DNA bead under high chaotropic salt concentrations. * The sample and lysis buffer are added toa sterile tube. The lysate is combined with alcohol, placed into the spin column, and then inserted into a tube. ¢ The removal of proteins and divalent cations is accomplished using multiple buffer washes and centrifugation steps. The removal of cations, such as Mg?*, prevents nucleases from further degrading the DNA. ¢ Pure DNA is eluted from the membrane into sterile water or TE buffer. Usable DNA Differential Extraction ¢ When dealing with evidence from a sexual assault kit, the swabs may contain non- sperm cells from the victim as well as sperm and non-sperm cells from the =i sz — » suspect. ‘ ¢ Differential extraction methods are used to separate spermatozoa from other cell types. * Spermatozoa are more difficult to lyse than other cells and the conditions can be set so that all cells except spermatozoa are lysed. * The supernatant containing the DNA from these cells is removed from the soerm cells which can then be lysed separately. Differential Extraction mame = won-sperm cell lysis e An extraction buffer containing a buffer, detergent, and Proteinase K is added to the sample and incubated. This step lyses all cells except soermatozoa. The supernatant containing the DNA from the lysed cells (epithelial cell fraction) is removed after pelleting the spermatozoa. ¢ The sperm pellet is often washed numerous times with a buffer to remove excess DNA from this lysis step. me operm cell lysis ¢ The pelleted sperm cells are lysed under more stringent conditions using a buffer, detergent, DTT, and a higher concentration of Proteinase K (sperm cell fraction), and are subsequently incubated. uum orn fractions are extracted separately and purified. Robotics Robotic liquid handling technology in automated DNA extraction systems can streamline the tasks involved in isolating DNA from a sample. Reproducibility Increase efficiency 2. Quantification Quantification ¢ Quantification determines how much DNA is present to optimize downstream procedures. ¢ Examples of quantification methods include: ¢ Yield gels ¢ Spectrophotometry ¢ Slot blot hybridization ¢ Quantitative PCR (qPCR) Yield Gels bat OF bed i wd The yield gel technique is a semi- quantitative/qualitative assay that allows for the estimation of the concentration and quality of DNA in a specimen. The method consists of the electrophoresis of DNA in an agarose gel matrix incorporating a fluorescent intercalating aa —a. dye such as ethidium bromide (EtBr). The concentration of a sample can be veiw determined by comparing the intensity of the fluorescence of the sample to that of the calibration standards. Absorption Spectrophotometry ¢ Absorption spectrophotometry is based on the property of molecules absorbing light at specific wavelengths. ° The optical density of a solution with a 1 © 2.505 cm path length, containing 50yug/ml of 5 2.005 double-stranded DNA or 40 ug/ml of s 1.50- single-stranded DNA, is 1.00 at a 2 4,00- =< wavelength of 260nm. 950- * The quality, or purity, of the sample can be 0.00- determined by comparing the — yl | I measurements at 260nm and at 280nm 220 200 300 340 380 (the wavelengths for which DNA and Wavelength (nm) protein absorb).  Slot Blot Hybridization TAN ¢ Slot blot hybridization was commonly used, and many laboratories elne, used the commercial QuantiBlot® kit. Pte te. ¢ Extracted DNA is denatured, and the single-stranded DNA is bound to a ate tye positively charged nylon membrane. ci o * "" tet +. « After the DNA is bound to the membrane, a probe complementary to the ‘ "fe hess : D17Z1 locus (present in high quantities in higher primates) is applied and eaoenes allowed to hybridize to the DNA. ries ws -* * The hybridized complex is detected by one of several methods. The os a wwe chemiluminescent reactions cause the release of photons that are captured castes on film or a digital imaging device. o*.~ ; wwe ¢ The amount of DNA in the sample is estimated by comparison of the density of the band or bands observed to that of the standards. Slot Blot Hybridization Calibration Unknown Samples Calibration standards at standards 20 ng 0.63 ng 10 ng Quantitative PCR ° Quantitative PCR (qPCR), sometimes referred to as real-time PCR, is the most accurate, precise, and efficient method currently available for human DNA quantification. ° Quantification uses the same cycles as PCR but incorporates dyes into the new copies. 24 Quantitative PCR * qPCR monitors the increase in fluorescent signal throughout the PCR cycling SYBR® Green Dye process by detecting and measuring the accumulation of fluorescent dyes as the reaction progresses. ¢ The change in fluorescence is monitored After polymerization, the dye binds between samples and standards so that a and fluoresces comparison can be made. 25 Quantitative PCR * The amount of amplifiable DNA present in the original sample can be estimated. ¢ qPCR helps to determine if sufficient human DNA is present to proceed with STR analysis and may indicate if PCR inhibitors are present. 26 Quantitative PCR Commercial Kits: ¢ Ouantifiler® Human ¢ Ouantifiler® Duo ¢ Plexor HY  ¢ The Quantifiler® kit quantifies the total amount of amplifiable human DNA in a sample by targeting the hTERT (human telomerase reverse transcriptase) gene. Quantifiler® =. Human ABI 7500 Real Time PCR System Quantifiler® Human Expenment dard Cu one Type Standx Reagents jm os TE Go| mn: * Contains two assays: Spas A i - [Benes [ Remon] alee) ¢ IPC (Internal PCR Control). an rrr TTT Tl ¢ Quant Human WY ddddddaddeldls ¢ Threshold defines level of detectable i, TI i) fluorescence ° C,= fluorescent signal increases beyond threshold setting te Seow Deeaneet— |") Ranetne Mat Fret Targets Donets Bet Met B Target & } 6 \ewmene £55 ts eantars Negus Cone See _— ‘\ ~~ => —.~ = fq’ ~ ™~. andard Curve TTS Standard Curve (Target: Quant Human) aqyan’ 35.5 35.0 345 Quantifiler® 34.0 335 33.0 32.5 32.0 Human 31.6 31.0 30.5 Threshold Cycle (Ct) 30.0 29.6 29.0 28.6 28.0 275 27.0 265 26.0 eStandard Curve 265 + + 25.0 *, ° Slope: ~-2.9 to -3.3 245 ta 24.0