Profili Forensic Chem 11/2, 11/4
Profili Forensic Chem 11/2, 11/4 FRSC 367
Popular in Forensic Chemistry
Popular in Criminology and Criminal Justice
This 12 page Class Notes was uploaded by Kayli Antos on Saturday November 7, 2015. The Class Notes belongs to FRSC 367 at Towson University taught by Mark Profili in Summer 2015. Since its upload, it has received 29 views. For similar materials see Forensic Chemistry in Criminology and Criminal Justice at Towson University.
Reviews for Profili Forensic Chem 11/2, 11/4
Report this Material
What is Karma?
Karma is the currency of StudySoup.
Date Created: 11/07/15
Forensic Chemistry – Profili – Fall 2015 Weapons Of Mass Destruction Terrorism ¤ The Code of Federal Regulation defines it as “the unlawful use of force and violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof, in furtherance of political or social objectives”. Types Of Domestic Terrorism ¤ Right-Wing ¤ Left-Wing ¤ Special Interest International Terrorism ¤ Movements ¤ Formal Organizations ¤ State-Sponsored Weapons Of Mass Destruction ¤ B iological ¤ N uclear ¤ Incendiary ¤ C hemical ¤ E nergetic Biological Weapons ¤ Disease-Causing Organisms Bacteria- living organisms Viruses- fragments of DNA/RNA, not quite alive Prions ¤ Toxins are produced by or extracted from living organisms. ¤ Bacterial Toxins Fungi/other molds Plant extracts Animal toxins Radiation Weapons ¤ Improvised nuclear weapons ¤ Stolen nuclear weapons ¤ Radiological dispersion device ¤ Nuclear Targets And Sources Nuclear power plants Medical and diagnostic facilities Military, scientific, and industrial facilities Incendiary Weapons ¤ Review fire behavior and components from arson chapter. Chemical Weapons ¤ Industrial Chemicals ¤ Military Weapons riot agents nerve agents blister agents blood agents choking agents Energetic Weapons ¤ Explosives are usually made up of an initiator, a booster, and a man charge. ¤ Review explosives chapter. Bioterrorism ¤ Using biological agents or their toxins against people, animals, or crops. ¤ There are many sources from which to acquire these agents including over 1,000 microbiological libraries, national bioweapons programs, and naturally occurring diseases. ¤ Most cases are not bioterrorism but rather biocrime. Historical Bioweapon Use ¤ In 1346, the Tartan army catapulted plague-infected corpses over the walls of the city Kaffa, forcing the inhabitants to surrender. ¤ In 1763, the English gave Native Americans smallpox-infected blankets. ¤ In 1940, Japan used planes to drop 5kg of fleas carrying the plague over China. 109 deaths were recorded. ¤ In 1984, the Rajneeshees cult in Oregon contaminated salad barns with Salmonella. Why Would Someone Use A Biological Agent? ¤ Agents are inexpensive and simple to produce. ¤ The civilian population is very susceptible. ¤ Agents are often colorless and odorless and therefore difficult to detect and treat. ¤ Organisms are fairly stable in the environment. ¤ The first sign of an attack is often illness which doesn’t occur for several days. ¤ Will rapidly overwhelm medical capabilities and cause panic. ¤ Leads to stress, anxiety, and loss of confidence in the government by the general population. Biological WMD Differences From Chemical WMD ¤ All agents are solids and but be dispersed by aerosols. ¤ Easier to make but more difficult to use. ¤ All agents are or are made from living organisms. ¤ Many agents are destroyed by sunlight. ¤ Are more toxic by weight than chemical WMD. ¤ Can be toxic by inhalation, ingestion, or injection. ¤ The action is usually delayed 1-10 days. Characteristics Of Biological Weapons ¤ Cannot penetrate unbroken skin. ¤ Are non-volatile. ¤ Are undetectable by the senses. ¤ There is limited field detection. ¤ Have a range of effects. ¤ Routes of entry. ¤ Are obtained from nature. ¤ Have delayed effects. ¤ Will multiple and overcome the body’s immune system. ¤ Can cause epidemics. Potential Biological Agents ¤ Bacteria- Anthrax and the plague. ¤ Q fever- Rickettsia ¤ Virus- Small Pox, Ebola, Venezuelan Equine Encephalitis (VEE) ¤ Toxins- Staphylococcal Enterotoxin B, Botulinum, Ricin What Are Today’s Threats? ¤ New, highly trained terrorist organizations developing. ¤ Terrorist organizations increasingly use new technology like the internet and wireless communications which make them difficult to track. ¤ The targeting of the civilian population. Targeting Of The Civilian Population ¤ Tokyo subway Sarin attack ¤ Oregon salad bars (1984) ¤ World Trade Center bombings (1993 and 2001) ¤ Oklahoma Federal Building Bombing ¤ US Embassy bombings in Kenya and Tanzania ¤ Plane bombs of 9/11 What Is Being Done To Detect Biological Agents? ¤ Syndromic Surveillance- the first systems appeared in the late 1990’s with demand increasing in recent years. ¤ Environmental Sampling- first responders receive training from a variety of agencies. ¤ Biological Agents Early Warning System- the EPA’s Biowatch program. Possible Delivery Systems ¤ Point Source Delivery letter/package sprayer ¤ Vectors the US experimented with mosquitos infected with Yellow Fever Japan used fleas to spread the plague in China ¤ Upwind Line Delivery a highly modified cropduster/rooftop dispersion issues of inversion and dilution ¤ Human Carrier “person-to-person” suicidal delivery only certain agents like pneumonic plague and small pox are transmissible Which Agents Have The Greatest Potential To Cause Mass Casualties? ¤ Anthrax and Smallpox ¤ They historically have a high devastation potential. ¤ They are both highly lethal. ¤ They are both stable in aerosol form. ¤ They both have a devastating psychological impact. ¤ Can be produced in large quantities. Anthrax ¤ Bacillus anthracis ¤ Spores and tough and resilient. ¤ Initial symptoms are non-specific. ¤ If untreated, the mortality rate is high. ¤ When caught it time, it’s easily treated. ¤ Easy to spread. Smallpox ¤ Variola virus (DNA virus). ¤ Only infects humans. ¤ Can rapidly be inactivated by UV light and chemical disinfectants. ¤ Can stay viable for years when in crusts at room temperature. ¤ Symptoms are noticed 7-17 days after exposure. US History Of Smallpox ¤ 1949 last US case reported ¤ 1972 last US routine public immunization ¤ 1976 last US routine immunization for health care workers ¤ 1982 last licensed manufacturer of vaccine stops production ¤ 1990 last US military vaccination Smallpox Treatment ¤ There is a vaccine that can be given within 3-4 days of exposure that will limit the complications of the disease. ¤ Antibiotics can be given for secondary infections but will not help with the disease itself. ¤ Mortality in the past was 30% but could be worse if it was weaponized. What Constitutes A Reasonable Biological Agent Threat? ¤ Since biological agents do not have immediate effects, there will be no initial evident casualties or signs of terrorist activity. ¤ Look for inappropriate/unusual labeling on packages, odd appearance of packages, anything else suspicious. Chemicals Vs. Biological Agents ¤ Unlike biological agents, chemical agents will usually preset immediate symptoms including irritation of mucous membranes, headaches, and breathing problems. ¤ Some symptoms can be increased or caused by panic. ¤ Chemical agents are usually vapors or liquids. What Happens To A Biological Sample At The Lab? ¤ A low threat assessment is a culture sample on a plate. ¤ A high threat assessment with exposure is a priority test using PCR and a culture. What Makes A Chemical A Good Terrorist Weapon? ¤ Should be a less condensed state and have highly toxic effects. Physical States Of Chemicals ¤ Gases are the easiest to disseminate but will disperse quickly. ¤ Liquids will evaporate to vapors which are also toxic, or will remain as liquid. Hazard for contact with skin. ¤ Solids are difficult to disseminate and enter the body. Toxic Effects ¤ Depends on: How much is in the body. How quickly is it taken in. The route of entry (inhalation, skin contacts, ingestion, injection.) Dissemination Of Chemicals ¤ Depends on the state of the agents. ¤ Device can be explosive. ¤ Device can be non-explosive: closed container with a burster gas cylinder with a valve containers with chemicals that will give off gases when they’re mixed aerosol generators Types Of Chemical Agents ¤ Toxic Industrial Chemicals chlorine hydrogen cyanide phosgene arsine phosphine are all gases at room temperature can all either be easily purchases, stolen, or made ¤ Military Unique Chemicals are all liquids at room temperature no industrial uses difficult to make, buy, or steal Sarin Soman Tabun VX are nerve agents mustards Lewisite are blister agents Properties Of Nerve Agents ¤ Some will evaporate quickly and some will only evaporate a little. ¤ None are commercially available. Some may be bought or stolen from foreign military. ¤ Synthesis requires a lab and an experienced chemistry. ¤ Are rapid acting and not detectible without instrumentation. ¤ Require protection by gas mask/respirator and chemical protective suit. ¤ All require decontamination. Specific Nerve Agents ¤ Sarin (GB)- very volatile and vapor is very toxic; non-persistent ¤ Soman (GD)- less volatile, more toxic, more persistent, and more difficult to treat than Sarin ¤ VX- not volatile, very persistent, much more toxic by contact than GB or GD ¤ All exist in large military stockpiles Blistering Agents ¤ Primarily blister the skin on contact with liquid ¤ Much less toxic than the nerve agents Forensic Toxicology Toxicology is the study of poisons. Forensic toxicology is the examination of the aspects of toxicology that have legal applications. Forensic toxicologists assist the forensic pathologist by analyzing toxins. The ED 50 is the effective dose. This is the dose that will induce the desired response in half of the test population. The LD 50 is the toxicologically-lethal dose. This is the dose that will lead to death in half of the test population. Applications Of Forensic Toxicology ¤ Postmortem drug testing is a death investigation with the goal of determining whether or not drugs were the cause of a contributing factor in a death. ¤ Workplace drug testing of biofluids, typically blood and urine. All federal agencies require drug testing prior to employments. Specific occupations like police officers or customs agents may be subjected to random testing. 90% of the largest US corporations require urine to be drug free. ¤ Evaluation of contraband material to identify them. Normally performed by forensic chemists in a crime lab. Interpreting Postmortem Investigations ¤ A forensic toxicologist will work with the forensic pathologist to determine the cause and manner of death. ¤ A toxicologist will determine what the specific toxin is. ¤ The presence an amount of a toxin can help to determine if the death was an accident, suicide, or homicide. ¤ There are many factors that can undermine the findings of a toxicologist like it is impossible to rule out a toxins involvements in a death and that no controlled experiments have been done to determine the lethal doses of toxins in people. ¤ A forensic toxicologist must: measure all toxins with great care consider all findings consult data collections of lethal blood concentrations and toxin amounts in tissues consider all variables before reaching a final conclusion Testing Process ¤ Blood is the most important specimen in toxicology because the amount of toxin in the blood is most closely connected to lethality. ¤ Samples of 50-100mL are taken from the heart and a peripheral site. ¤ Urine is the most commonly tested sample because large amounts can be collected and it’s noninvasive. ¤ In a postmortem investigation, urine is collected in order to minimize the false negative associated with blood evaluations. Certain toxins may also be found in higher levels in the urine than the blood. ¤ Gastric contents can be tested in the sudden death of a person who had large amounts of a lethal agent sin their stomach. ¤ If a substance is highly toxic it might be found in much higher quantitates in the stomach than the blood. ¤ In suicide cases there are typically large amounts of the drug found in the stomach. ¤ The vitreous humor is resistant to purification and may contain biochemical or drugs. ¤ In decaying cadavers, it may the only fluid left. ¤ It can contain chemical abnormalities. ¤ The liver is the organ that’s the most involved in drug metabolism. ¤ It may contain significant amounts of drugs which can be used for identification. ¤ Bile drains from the liver and may contain high levels of drugs like opiates. Types Of Drugs ¤ Opiates Cause euphoria Examples are morphine and codeine Uses as an analgesic Synthetic examples are oxycontin, oxycodone, oxymorphone, and hydrocodone ¤ Amphetamines Simulants Cause an excitatory response characterized by an elevated heart rate, BP, and respiratory rate May cause euphoria Primarily synthetic ¤ Cocaine Stimulant Resembles meth in abusive potential Derives from the Coca leaf Normally extracted with HCl Treating cocaine HCl with a base makes crack which can be smoked May only be found in urine for a brief period ¤ Cannabinoids Marijuana comes from Cannabis sativa Many psychoactive compounds can be derived from the plant THC (tetrahydrocannabinol) is the primary active agent and is 2-6% by weight Hashish is the oily extract that can be up to 12% THC Block concentrations peak 10-20 minutes after inhalation Causes euphoria, perceptive alterations, memory impairment, mood swings, and intoxication Lasts about 2 hours Can be found in urine for up to 2 months following heavy usage Pharmaceutical Materials ¤ Prescribed medications can be lethal. ¤ Accidental deaths result from the incorrect dose of a drug or taking the wrong drug. ¤ Organ damage can result from a medical condition which prevents a person form metabolizing a drug. ¤ This can cause the drug to build up in the blood to toxic levels. Major Categories Of Medical Agents Involved In Deaths ¤ Barbs ¤ Cardioactive agents (lidocaine etc) ¤ Antipsychotic drugs (phenothiazine) ¤ Antiepileptic drugs (phenobarbital) ¤ Antidepressants/SSRIs Nonmedical Agents ¤ Alcohol ¤ Cyanide ¤ CO ¤ Hydrocarbons Alcohol ¤ Disrupts nerve cell membranes. ¤ Normally enters body through the small intestine. ¤ 90% of alcohol ingested is broken down into acetaldehyde and acetic acid. ¤ Blood level peaks 90 minutes after ingestion. ¤ 1.5 oz of alcohol raises the blood concentration by .02%. ¤ Toxicity is a result of the dose and level of alcohol in the blood. ¤ Chronic alcohol abuse can lead to fatty accumulation of the liver, liver cancer, and psychosis like syndromes. ¤ Blood alcohol can be measured by GC. ¤ Concentrations of 500mg/dL and up typically cause death. Cyanide ¤ Acts the fastest when in gas form. ¤ Interrupts the electron transport within mitochondria which prevents them from making energy. ¤ Death will occur in less than a minute ¤ Levels about 2500ng/mL are fatal. Carbon Monoxide ¤ Binds to hemoglobin irreversibly and prevents it from transporting oxygen. ¤ Also binds to myoglobin and cytochrome oxidase to prevent aerobic respiration. ¤ Death occurs at carboxyhemoglobin levels about 60%. Hydrocarbons ¤ Commonly found in nature. ¤ Less toxic than CO or cyanide. ¤ Death is usually caused by oxygen deprivation or accident due to erratic behavior from the effects of hydrocarbons. Methods Of Drug Detection ¤ Blood Best fluid to use Most expensive and painful ¤ Urine Most commonly used Simple Usually a direct reflection of what was in the blood ¤ Breath/Saliva Can also be used Urinalysis ¤ Tests are made for metabolites. ¤ Will know when old urine is substituted for fresh urine because fresh urine will be body temperature. ¤ Adulteration with alkali or acid can be detected by measuring the pH. ¤ Adulteration with ammonia can be detected by smell. ¤ Drinking a large amount of water to dilute the urine can be determined by measuring the specific gravity which should not be less than 1.010. Analytical Methods In Forensic Toxicology ¤ Screening, presumptive testing for positive. ¤ Confirmation, conform presence. Sensitive and specific. Screening Tests ¤ Immunoassays Most used. Detect very small quantities of a certain drug (25-1000ng/mL) in urine. Use antibodies to detect metabolites. Attachment of the antibody to the drug causes a color change or the release of low levels of radiation. Two popular imuunoassays are EMIT *Enzyme Multiplied Immunoassay Test) and ABUSCREEN. Both detect 8 major classes of drugs: Amps Barbs Benzos Cannabinoids Cocaine Methaqualone Opiates PCP ¤ Rapid Assay Devices Quicker, cheaper, and simpler. Require no lab processing and therefore can be used on site. testTcup detects cocaine, morphine, and THC. Based on competitive microparticle capture inhibition-competition between a drug and a drug conjugate on the membrane in the test chamber. Urine collected directly into the cup. When enough of the drug is present in the sample it binds to the antibody coated microparticles. Inhibits the particles from binding to the drug conjugate. This prevents a blue band from forming on the test plate which indicated a positive result. Drug Tests ¤ First screening test is a chemical spot test followed by TLC or UV-Vis. ¤ Then confirmed with GC, GCMS, FTIR. ¤ Liquid Chromatography-Mass Spectrometry Liquid chromatograph replaces the gas chromatograph. Mixture swept into liquid instead of gas. Compatible with every organic chemical because no heat is needed for conversion to gaseous state. Costs 3x as much as GCMS Lower resolution than GCMS. False Positive ¤ A false positive can come from a human error, but this isn’t common. ¤ More likely to come from another chemical being positive in the blood (like Ritalin will give a false positive for Amp). ¤ Can use a confirmatory test to clear up error. False Negatives And Pitfalls ¤ Occur less frequently than false negatives. Retention Time Of Drugs In Urine ¤ Amps 48 hours ¤ Short acting barbs 24 hours ¤ Long acting barbs 2-3 weeks ¤ Benzos 3 days-4-6 weeks ¤ Cocaine 2-4 days ¤ Ethanol 2-14 hours ¤ Cannabinoids 4x/week 5 days ¤ Cannabinoids daily 10 days-2 weeks ¤ PCP 8-30 days Metal Analysis ¤ Mean metals like lead, arsenic, mercury, plutonium, and cadmium are dangerous to humans. ¤ Can be measured by colorimetric testing. ¤ Atomic Absorption Spectrophotometry (AAS) Most popular. Ions in the metal are reduced to atoms, typically by flame (FAAS), and a specific wavelength of light is used to raise a valence electron to a high energy state. The detector measures the light before and after the sample in introduced and the decrease in light is proportional to the concentration of the metal in solution. ¤ Neutron Activation Analysis (NAA) Highly specialized for metals. Sample placed in presence of low energy neutrons and undergoes radioactive changes. Emit gamma rays or x-rays. Characteristics of the emitted radiation allows the analyst to identify the metals and measure their concentration. ¤ Inductively Coupled Plasma-Mass Spectrophotometry (ICP-MS) Best and most modern technique. Argon atoms are subjected to radio frequencies that make them collide and increase the temperature to over 6000 degrees Celsius. Several metals can be analyzed at once. Low detection limits.