Forensics Quiz 2 - Lecture notes 5 PDF

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Forensics Quiz #2

Toxicology & Seized Drugs  Toxicology – Study of Poisons  Forensic Toxicology – Examination of all aspects of toxicity that may have legal distinctions  Postmortem Toxicology – Death investigation with goal of establishing whether drugs were the cause of death o Examples of Testing:  Overdoses  Suspected Poisoning  Workplace Drug Testing – Evaluation of biofluids (blood and urine) o Federal agencies require pre-employment drug testing o Random testings for police and custom agents are allowed  Evaluation of Contraband Material – Identifying and evaluation of contraband materials. o Examples: Seized Drugs & Methamphetamine  Xenobiotic: Foreign substances to the body  Drug: Compound that causes physiological effect (Ex: Aspirin)  Poison: When ingested, results in toxic or damaging physiological effects ADME: - Absorption, Distribution, Metabolism, and Excretion  Common types of Drug/Toxin ingestion o Inhalation o Oral o Injection – Muscle or Vein/Artery o Absorption (Skin) Testing Processes  Blood: Most important specimen in postmortem toxicology o Two specimens of 50 – 100 milliliters are taken:  One from heart / central blood  One from a peripheral site (i.e femoral) 

 Urine: Most frequently used in pre-employment due to: o Large amount can be easily collected o Minimizes false negative findings associated with only blood evaluation. o Certain toxins are found in higher levels in urine than blood  Gastric Contents – Contents of stomach may be tested in sudden death of person who had large quantities of lethal agent in stomach  Liver: Organ most involved in drug metabolism  Bile: Drains from liver and may be very rich in certain types of drugs (Opiates) Drugs  Opiates: Ability to cause profound euphoria o Morphine and Codeine o Grown mostly in South East Asia  Morphine o Extracted from Opium  Heroin o Synthesized from Morphine o Lasts 3-4 hours. Consists of drowsiness and sense of well-being  Codeine o Present in Opium o Prepared synthetically from Morphine  Amphetamines – Stimulants which create excitatory condition characterized by elevation of heart rate, blood pressure, and respiratory rate.

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o Amphetamines are primarily synthetic o Amphetamines (speed) and methamphetamine (meth) are most widely known Marijuana refers to a preparation derived from the plant Cannabis.  tetrahydrocannabinol, or THC is the hallucinogenic property in Marijuana

 THC-rich resin is known as Hashish  Can be tested for in urine and discovered for up to two months following heavy usage

PCP – Phencyclidine  A feeling of detachment from world  Higher doses can cause severe perceptive distortions  These distortions may include psychosis, violent behavior, paranoia and hallucinations  After regular use of PCP, results can be found in urine for about one week Alcohol – Ethanol is beverage alcohol  90 minutes after ingestion is normally time blood hits peak alcohol levels  Chronic alcohol abuse can contribute to: o Fatty accumulation of liver and up to hepatoma- liver cancer o Psychosis like syndromes in the brain

 Cyanide o Fastest acting form is cyanide gas o Very toxic substance

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o Cyanide acts by interrupting the electron transport within mitochondria of cells – without biochemical energy life is not possible o Death occurs quickly from cyanide- inhalation of large amounts results in death in less than one minute  Carbon Monoxide o Binds hemoglobin more tightly to oxygen and prevents it from transporting oxygen to cells* o CO Testing Reveals  Carboxyhemoglobin levels exceeding 60% are at significant level of death * Death is usually due to oxygen deprivation or accident following erratic behavior brought on by effects of hydrocarbons on brain

Chromatography, spectrophotometry, and mass spectrometry are all readily used by a forensic scientist to identify or compare organic materials. Chromatography is a means of separating and tentatively identifying the components of a mixture. Spectrophotometry is the study of the absorption of light by chemical substances

Death Investigations & Coroner Coroner Act:  Police Assistance  Duty to give Info  Take Charge of Wreckage

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o Coroner issues warrant to take possession of the body of a person who has met death by violence in a wreck and with approval can take charge of wreckage. Investigative Powers o Coroner may examine/take possession of any dead body o May enter and inspect any place where a dead body is and any place where Idem o May inspect any place deceased person was or believed to have be prior to death with reasonable ground. o Seize anything is believed to have purpose to the investigation Delegation of Powers o May authorize a legally qualified practitioner/police officer exercise any/all of coroners’ powers Power to Examine Body o Purposes of Inquest o Where an inquest is held, it shall inquire into the circumstances of the death and determine:  Who, When, How, Where

 Reports of Post-mortem Findings o A person, other than the pathologist who performed the post-mortem examination, who conducted any other examination or analysis under section 28 shall forthwith report his or her findings in writing to the pathologist who performed the post-mortem examination

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