0. Chapter 6 Toxicology: Poisons and Alcohol
“All substances are poisons. There is none which is not. The right dose differentiates a poison and remedy.”
—Paracelsus ( ). Swiss physician and chemist

1. Toxicology and Alcohol
Students will learn:
A quantitative approach to toxicology.
The danger of using alcohol.

2. Toxicology and Alcohol
Chapter 6
Toxicology and Alcohol
Students will be able to:
Discuss the connection of blood alcohol levels to the law, incapacity, and test results.
Understand the vocabulary of poisons.
Design and conduct scientific investigations.
Use technology and mathematics to improve investigations and communications.
Identify questions and concepts that guide scientific investigations.
Communicate and defend a scientific argument.

3. Toxicology
Definition—the study of the adverse effects of chemicals or physical agents on living organisms.
Types:
Environmental—air, water, soil
Consumer—foods, cosmetics, drugs
Medical
Forensic

4. Forensic Toxicology Postmortem—medical examiner or coroner
Criminal—motor vehicle accidents (MVA)
Workplace—drug testing
Sports—human and animal
Environment—industrial, catastrophic, terrorism

5. Toxicology Toxic substances may: Be a cause of death
Contribute to death
Cause impairment
Explain behavior

6. Historical Perspective of Poisoners
Olympias—a famous Greek poisoner
Locusta—personal poisoner of Emperor Nero
Lucretia Borgia—father was Pope Alexander VI
Madame Giulia Toffana—committed over 600 successful poisonings, including two Popes.
Hieronyma Spara—formed a society to teach women how to murder their husbands
Madame de Brinvilliers and Catherine Deshayes—French poisoners.
AND many others through modern times.

7. 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”

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.

9. 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

10. 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

11. Death by Water Hold your wee for a wii
In 2007, a mother tried to win a wii game for her son at a radio show contest
Contestants had to drink a water bottle every 5 minutes without using the bathroom
The mother died of water poisining

12. How much water is too much water?
1.5 to 2.0 gallons can be toxic to your body

13. Toxicity Classes LD50 (rat,oral) Toxicity
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
mg/kg
to an ounce
moderately
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

14. 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)

15. Symptoms of Various Types of Poisoning
Type of Poison Symptom/Evidence
Caustic Poison (lye) Characteristic burns around the lips and mouth of the victim
Carbon Monoxide Red or pink patches on the chest and thighs, unusually bright red lividity
Sulfuric acid Black vomit
Hydrochloric acid Greenish-brown vomit
Nitric acid Yellow vomit
Phosphorous Coffee brown vomit. Onion or garlic odor
Cyanide Burnt almond odor
Arsenic, Mercury Pronounced diarrhea
Methyl (wood) or Nausea and vomiting, unconsciousness,
Isopropyl (rubbing) alcohol possibly blindness

16. Critical Information on Poisons
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”

17. 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

18. Forensic Autopsy Look for: Order toxicological screens
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

19. Human Specimens for Analysis
Blood
Urine
Vitreous Humor of Eyes
Bile
Gastric contents
Liver tissue
Brain tissue
Kidney tissue
Hair/nails

20. Alcohol—Ethyl Alcohol (C2H5OH)
Most abused drug in America
About 40% of all traffic deaths are alcohol-related
Toxic—affecting the central nervous system, especially the brain
Colorless liquid, generally diluted in water
Acts as a depressant
Alcohol appears in blood within minutes of consumption; minutes for full absorption
Detoxification—about 90% in the liver
About 5% is excreted unchanged in breath, perspiration and urine

21. Rate of Absorption Depends on: amount of alcohol consumed
the alcohol content of the beverage
time taken to consume it
quantity and type of food present in the stomach
physiology of the consumer

22. BAC Blood Alcohol Content
Expressed as percent weight per volume of blood
Legal limits in all states is 0.08%
Parameters influencing BAC:
Body weight
Alcoholic content
Number of beverages consumed
Time between consumption

23. BAC Burn off rate of 0.015% per hour but can vary: Male Female
BAC male = x (oz) x (% alcohol)
body weight
Female
BAC female = x (oz) x (% alcohol)

25. Field Tests
Preliminary tests—used to determine the degree of suspect’s physical impairment and whether or not another test is justified.
Psychophysical tests—3 Basic Tests
Horizontal gaze nystagmus (HGN): follow a pen or small flashlight, tracking left to right with one’s eyes. In general, wavering at 45 degrees indicates 0.10 BAC.
Nine Step walk and turn (WAT): comprehend and execute two or more simple instructions at one time.
One-leg stand (OLS): maintain balance, comprehend and execute two or more simple instructions at one time.

26. Implied Consent Law Driver must consent to tests or lose license
Implemented to prevent refusal to take breath test on grounds of self incrimination

27. Mouth Alcohol Alcohol present in a breath test subject’s mouth
Presence of mouth alcohol causes the concentration detected in exhaled breath to be higher then the actual blood concentration
Sources include
Regurgitation
Belching
Recent intake of an alcoholic beverage
Recent gargling of alcohol containing mouthwash

28. Forensics 4/1/13 Welcome back! Any good spring break stories?
Don’t forget to turn in extra credit assignment
Midterm Friday: includes CH 6 quiz (toxicology) CH. 8 blood, CH. 5 Drugs
CH 6 supp questions are due this Fri 4/5/12
(Bring your textbook Wednesday)

29. Case Study Answer the following questions as a group:
Read the Case Study: Death by Tylenol
Answer the following questions as a group:
1. Where did this event take place?
2. What is Product Tampering ?
3. How do you think the investigators determined the capsules contained a quantity of poison “ten thousand times what was needed to kill an average person” ?

30. The Metabolism of alcohol
The transformation of a chemical in the body to other chemicals to facilitate its elimination from the body
Happens in three steps: absorption, distribution and elimination

31. Absorption
Alcohol enters the blood stream by passing across the wall of the stomach and small intestine

32. Distribution
The alcohol becomes evenly distributed throughout the watery parts of the body (including the blood and the brain)

33. Elimination Alcohol is eliminated in two ways:
1.oxidation: the combination of alcohol with oxygen to produce carbon dioxide and water (oxidation occurs in the liver)
2. excretion: elimination of alcohol from the body in an unchanged state (breath and urine)
95% of consumed alcohol eliminated through oxidation

34. Alveoli
Small sacks in the lungs that exchange oxygen, carbon dioxide and other gases with the blood
Carbon dioxide and other volatile chemicals (alcohol) are then expelled through the nose and mouth

35. Henry’s Law
When a volatile chemical is dissolved in a liquid and is brought to equilibrium with air, there is a fixed ratio between the concentration of the volatile compound in the air and its concentration in the liquid; this ratio is constant for a given temperature. THEREFORE, the concentration of alcohol in breath is proportional to that in the blood.
This ratio of alcohol in the blood to alcohol in the alveolar air is approximately 2100 to 1. In other words 1 ml of blood will contain nearly the same amount of alcohol as 2100 ml of breath.

36. The Breathalyzer More practical in the field
Collects and measures alcohol content of alveolar breath
Breath sample mixes with 3 ml of % K2Cr2O7 in sulfuric acid and water
2K2Cr2O7 + 3C 2H5OH + 8H 2SO4  2Cr2(SO4) K2SO4 + 3CH3COOH + 11 H2O
Potassium dichromate is yellow, as concentration decreases its light absorption diminishes so the breathalyzer indirectly measures alcohol concentration by measuring light absorption of potassium dichromate before and after the reaction with alcohol

37. The Breathalyzer More modern breathalyzers don’t use chemicals
1. Infrared Light Absorption: Alcohol present in a subject’s breath reacts with a particular wavelength of inrared light
2. The Fuel Cell: a chemical reaction involving alcohol produces electricity (electrons)

38. Generalizations
During absorption, the concentration of alcohol in arterial blood will be higher than in venous blood.
Breath tests reflect alcohol concentration in the pulmonary artery.
The breathalyzer also can react with acetone (as found with diabetics), acetaldehyde, methanol, isopropyl alcohol, and paraldehyde, but these are toxic and their presence means the person is in serious medical condition.
Breathalyzers now use an infrared light absorption device with a digital read-out. Prints out a card for a permanent record.

39. Forensics 4/2/13
Don’t forget to bring your textbook Wednesday/Thursday so that you can work on your CH 6 questions and prepare for your midterm Friday!
Midterm Friday: Primarily on CH 6 with questions from CH 5 (drugs) and CH 8 (blood)

40. Is it ok for him to drive home? Explain
A man of 185 lbs drinks three shots (1.5 oz/shot) of Jack Daniels 80 proof (40%) in an hour.
What is his BAC?
Is it ok for him to drive home? Explain
What is the BAC if the above person is a woman?
Why the difference from male to female for BAC?

41. Rank from most to least intoxicated and explain your reasoning.
John 200lb had eight 8oz drinks on a full stomach.
Frank 170 lb had four 8oz drinks on an empty stomach
Gary 240 lb had six 8oz drinks on an empty stomach
Stephan 180 lb had six 8oz drinks on a full stomach

42. Blood Samples Clean injection site with non-alcohol astringent
Need preservative and refrigeration
Over time alcohol breaks down

43. Blood Samples
Forensic Laboratories use gas chromatography to determine blood-alcohol content
Compare alcohol peaks with KNOWN blood alcohol standards

44. Hair samples
The only viable option if it is necessary to ascertain whether a subject has been abusing a drug over a longer period of time
( drugs remain in blood stream for 24 hours and in urine for up to 72 hours)

45. Hair Samples Hair is nourished by blood flowing close to the hair root
Drugs present in blood become permanently trapped in hair’s protein structure
Can date the presence of drugs dating back over a period of weeks, months and sometimes years

46. Case Study Read the case study: Joann Curly: Caught by hair
Answer the following questions as a group:
1. If Bobby’s urine showed high levels of thallium in his body, does this indicate recent or distant exposure?
2. How did investigators determine that Bobby wasn’t exposed to the poison at work?

47. Match the organization to the concerns
Organizations
FDA 2) EPA 3) Consumer Product Safety Commission 4) DOT 5) OSHA
Concerns
Toxins in consumer products
Exposure to chemicals in the work place
Agricultural and industrial chemicals
Pharmaceuticals, food additives and medical devices
Shipment of toxic chemicals

48. More Information on alcohol

49. People in the News
John Trestrail is a practicing toxicologist who has consulted on many criminal poisoning cases. He is the founder of the Center for the Study of Criminal Poisoning in Grand Rapids, Michigan which has established an international database to receive and analyze reports of homicidal poisonings from around the world. He is also the director of DeVos Children’s Hospital Regional Poison Center. In addition, he wrote the book, Criminal Poisoning, used as a reference by law enforcement, forensic scientists and lawyers.

50. More Information
Read more about Forensic Toxicology from Court TV’s Crime Library at: