1. Forensic science TOXICOLOGY AND ALCOHOL
The study of Poisons and how they affect the human body.

2. Toxicology
Toxicology—the study of the adverse effects of chemicals or physical agents on living organisms… Poisons
Types:
Environmental—air, water, soil
Consumer—foods, cosmetics, drugs
Medical, clinical, forensic

3. Mathieu Orfila (1787-1853) “Father of Toxicology”
He gave the subject its first formal treatment in 1813 in his book Traité des poisons, also called Toxicologie générale. (General Toxicology)
Wrote about the detection of poisons & their effects on animals.

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. Aspects of Toxicity Dosage – Has 5 factors:
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

7. Lethal Dose
LD50 refers to the dose of a substance that kills 50% of the test population, usually within four hours
Expressed in milligrams of substance per kilogram of body weight

8. Toxicity Classification
LD50 (rat,oral)
Correlation to Ingestion by 150-lb Adult Human
Toxicity
<1 mg/kg
a taste to a drop
extreme
1–50 mg/kg
to a teaspoon
high
50–500 mg/kg
to an ounce
moderate
500–5,000 mg/kg
to a pint
slight
5–15 g/kg
to a quart
practically nontoxic
Over 15 g/kg
more than 1 quart
relatively harmless

9. Symptoms of Various Types of Poisoning
Symptom/Evidence
Characteristic burns around the lips and
mouth of victim
Red or pink patches on the chest and
thigh, unusually bright red lividity
Black vomit
Greenish-brown vomit
Yellow vomit
Coffee-brown vomit, onion or garlic odor
Burnt almond odor
Extreme diarrhea
Nausea and vomiting, unconsciousness
possibly blindness
Type of Poison
Caustic poison (lye)
Carbon monoxide
Sulfuric acid
Hydrochloric acid
Nitric acid
Phosphorus
Cyanide
Arsenic, mercury
Methyl (wood) or isopropyl
(rubbing) alcohol

10. Famous Poisons
Hemlock or Conium is a highly toxic flowering plant indigenous to Europe and South Africa. It was a popular one with the ancient Greeks, who used it to kill off their prisoners. For an adult, the ingestion of 100mg of conium or about 8 leaves of the plant is fatal – death comes in the form of paralysis, your mind is wide awake, but your body doesn’t respond and eventually the respiratory system shuts down. Probably the most famous hemlock poisoning is that of Greek philosopher, Socrates. Condemned to death for impiety in 399 BC, he was given a very concentrated infusion of hemlock.

11. Famous Poisons
Arsenic has been called “The King of Poisons”, for its discreetness and potency – it was virtually undetectable, so it was very often used either as a murder weapon or as a mystery story element. But that’s until the Marsh test came and signaled the presence of this poison in water, food and the like. However, this king of poisons has taken many famous lives: Napoleon Bonaparte and Simon Bolivar to name a few. On another note, arsenic, like belladonna, was used by the Victorians for cosmetic reasons. A couple of drops of the stuff made a woman’s complexion white and pale. Just perfect!

12. Famous Poisons
If you’re watching Sherlock Holmes, then you’ll know about this one. The Botulinum toxin causes Botulism, a fatal condition if not treated immediately. It involves muscle paralysis, eventually leading to the paralysis of the respiratory system and, consequently, death. The bacteria enter the body through open wounds or by ingesting contaminated food. By the way, botulinum toxin is the same stuff used for Botox injections!

13. Famous Poisons
Cyanide seems to be extremely popular (spies use cyanide pills to kill themselves when caught) and there are plenty of reasons for this. Firstly, it is found in a great variety of substances like almonds, apple seeds, apricot kernel, tobacco smoke, insecticides, and pesticides. Murder in this case can be blamed on a household accident, such as ingestion of pesticide – a fatal dose of cyanide for humans is 1.5 mg per kilogram of body weight. Secondly, it’s a rapid killer: depending on the dose, death occurs within 1 to 15 minutes. Hydrogen cyanide gas was used by Nazi Germany for mass murders in gas chambers during the Holocaust.

14. Famous Poisons Mercury
There are three forms of mercury which are extremely dangerous. Elemental mercury is the one you can find in glass thermometers, it’s not harmful if touched, but lethal if inhaled. Inorganic mercury is used to make batteries, and is deadly only when ingested. And finally, organic mercury is found in fish, such as tuna and swordfish (consumption should be limited to 170g per week), but can be potentially deadly over long periods of time. A famous death caused by mercury is that of Amadeus Mozart, who was given mercury pills to treat his syphilis.

15. Famous Poisons Belladonna
The name of this plant is derived from Italian and means beautiful woman. That’s because it was used in the middle-ages for cosmetic purposes – diluted eye-drops dilated the pupils, making the women more seductive (or so they thought). Also, if gently rubbed on their checks, it would create a reddish color, what today would be known as blush! This plant seems innocent enough, right? Well, actually, if ingested, a single leaf is lethal and that’s why it was used to make poison-tipped arrows. The berries of this plant are the most dangerous – consumption of ten of the attractive-looking berries is fatal.

16. To Prove a Case of Poisoning
Prove a crime was committed:
1. Motive ?
2. Intent?
4. Access to poison?
5 Access to victim?
6. Death was homicidal?
7. Death was caused by poison?

17. Pattern of poisoning
Chemical products, most often swallowed by children include household cleaners (bleach, detergents) fuel (kerosene, paraffin), cosmetics, medicines, paints and products for household repairs and household pesticides.
Bites and stings of animals and insects, and ingestion of poisonous plants and seeds also considerably account for outdoor poisoning in children.

18. POISONING IN CHILDREN
Poison is a substance that causes harm if it gets into the body.
The poisoning in children could occur due to diverse causes and could be classified as
accidental,
homicidal or
suicidal.
Erroneous administration of overdosage of drugs by the parents or by the medical staff is also frequent.

19. Accidental Poisoning
Accidental poisoning in children is a global problem. The relative importance of poisoning as a cause of childhood morbidity and mortality increases when malnutrition and infections are brought under control.
Accidental poisoning is the twelfth leading cause of admissions in pediatric wards in India and accounts for about one percent of the hospitalized patients. Most cases of accidental poisoning are preventable. Continuing morbidity and mortality due to accidental poisoning is serious challenge to the pediatricians and public health officials.

20. Acute or Chronic Exposure
Acute exposure is a single contact that lasts for seconds, minutes or hours, or several exposures over about a day or less. Chronic exposure is contact that lasts for many days, months or years.
A poison may get into the body through ingestion, inhalation (gas, vapors, dust, fumes, smoke, spray), skin contact (pesticides), or injection (bites and stings, drug injection

21. Carbon Monoxide
Carbon monoxide poisoning can happen when fires, stoves, heaters or ovens are used in rooms, huts which do not have proper ventilation to let the gas out.

22. Ecology of poisoning
Interaction between the host and the environment (including easy access to the poisonous substances) determines the magnitude of the problem.
Age. About 40% of all cases of accidental poisoning in children are reported in the second year of life; about 12% of the cases occur in the first and 20% in the third year. As the children start crawling and walking around 1 year, they become very active and try to explore unfamiliar objects by putting these into their mouth and testing these. Thus they expose themselves to accidental poisoning. Hyperactive male children are more prone to accidental poisoning.

23. Environment: Lead poisoning is common in children living in areas were there are workshops for automobile, lead storage batteries or for manufacture of lead typesets for printing presses. Caustic soda poisoning used to be observed frequently in children of families, which prepared washing soap for domestic or commercial purposes in their own houses. Insecticides, medicines, naphthalene balls and kerosene are common household things which are potential hazards.
Rural or Urban areas:
The pattern of poisoning varies in rural and urban areas due to exposures to different types of potential poisons. Snakebites are more common in those wandering in fields.Also pesticides are more common in rural set up. The poor are driven by starvation to experiment on roots and fruits thus leading to poisoning.

24. Time relationship:
. Accidental poisoning is likely when normal routine in the house is disturbed such as during periodic house painting, packing and unpacking at the time of change of residence, going for vacation etc.

25. Classification of poisons
Based on the chief symptoms they produce
Corrosives- strong acids, strong alkalis, metallic salts.
Irritants- organic, inorganic.
Systemic- cerebral, spinal, peripheral, CVS, asphyxiants.
Miscellaneous- food poisoning & botulism.

26. History taking What poison was ingested. Time since ingestion.
Total amount of poison ingested.
Route of exposure.
Progression of signs and symptoms since ingestion.
Family history of epilepsy, mental sub normality, bleeding disorder.
Whether the patient is receiving other medications which may interact with the poison.

27. General signs and symptoms
Symptoms-odor, sweating, fever, delirium, convulsions, burns of mouth, blindness, GI symptoms, abnormal movements, coma.
Signs- miosis, mydriasis, blindness, facial twitching, dull & mask like expression, pallor, cyanosis, hypothermia, sweating, respiratory symptoms, CVS symptoms, CNS symptoms.

28. Diagnosis of Poisoning
Cardiac arrythmias. Tricyclic antidepressants, amphetamine, aluminium phosphide, digitalis, theophylline, arsenic, cyanide, chloroquin.
Metabolic acidosis. Isoniazid, methanol, salicylates, phenformin, iron, cyanide.
GIT disturbances. Organophosphorus, arsenic, iron, lithium, mercury.
Cyanosis. Nitrobenzene compounds, aniline dyes, and dapsone.

29. Basic Management of a poisoned patient
Antidotes are available for very few commonly encountered poisons, and treatment is usually non-specific and symptomatic. In such cases management consists of emergency first aid and stabilization measures, appropriate treatment to reduce absorption, measures to enhance life support followed by psychiatric counseling.

30. Identification of Poison
Identify the poison by careful history and helpful clues. Determine what, when and how much of the poison was ingested or inhaled. Find the supporting evidence for your diagnosis from the nature of the symptoms and physical signs. Some common toxidromes based on certain signs and symptoms.
Instrumental chemical analysis is the best way to find out exactly what it is.

31. Toxicology of Alcohol

32. Alcohol—Ethyl Alcohol (C2H5OH)
Most abused drug in America
About 40 percent of all traffic deaths are alcohol-related
Toxic—affecting the central nervous system, Acts as a depressant, especially the brain.
Colorless liquid, generally diluted in water
Alcohol appears in blood within minutes of consumption; 30–90 minutes for full absorption
Detoxification—about 90 percent in the liver
About 5 percent is excreted unchanged in breath, perspiration, and urine

33. Alcohol & Circulatory System
Alcohol is absorbed from the stomach and small intestines into the blood stream.
Alcohol is carried to the liver where the process of its oxidation starts.
It also goes through the circulatory system into the lungs where it is exhaled as a gas.

34. Alcohol Effects upon the body
As can be seen, the effects of alcohol upon the body are not good. With repeated exposure, general health declines.

35. Alcohol Breaks down to Acetaldehyde
In humans, acetaldehyde is a carcinogen and is the reason for hang overs. It causes drowsiness, delirium, hallucinations and loss of intelligence. Exposure may also cause severe damage to the mouth, throat and stomach; accumulation of fluid in the lungs, chronic respiratory disease, kidney and liver damage, throat irritation, dizziness, reddening and swelling of the skin

36. Alcohol & Circulatory System
In the lungs, carbon dioxide and alcohol leave the blood and oxygen enters the blood in the air sacs known as alveoli.
Then the carbon dioxide and alcohol are exhaled during breathing.

37. MEASURING THE ALCOHOL IN THE HUMAN BODY
A major branch of forensic toxicology deals with the measurement of alcohol in the body for matters that pertain to violations of criminal law.

38. 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

39. BAC: Blood Alcohol Content
Expressed as percent weight per volume of blood
Legal limit in all states is 0.08 percent
Parameters influencing BAC:
Body weight
Alcohol content
Number of beverages consumed
Time since consumption

40. BAC Calculation
Your liver oxidizes alcohol to filter it out of the body. This Burn-off rate is percent per hour, (but can vary)
Male
BAC =
Female
0.071  (oz)  (% alcohol)
body weight
0.085  (oz)  (% alcohol)
body weight

41. Blood Alcohol Calculator
://health.discovery.com/tools/calculators/alcohol/alcohol.html

42. Field Testing
Law enforcement officers typically use field sobriety tests to estimate a motorist’s degree of physical impairment by alcohol and whether or not 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.

43. Field Tests
Preliminary tests—used to determine the degree of suspect’s physical impairment and whether or not another test is justified
Psychophysical tests—three 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

44. Breath Testers
It’s the degree of the interaction of the light with alcohol in the captured breath sample that allows the instrument to measure a blood alcohol concentration in breath.
Some breath testing devices also use fuel cells.

45. The Breathalyzer More practical in the field
Collects and measures alcohol content
of alveolar breath
Breath sample mixes with 3 ml of percent K2Cr2O7 in sulfuric acid and water:
2K2Cr2O7 +3C2H5OH + 8H2SO4  2Cr2(SO4)3 + 2K2SO4 + 3CH3COOH + 11H2O
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.

46. Generalizations
During absorption, the concentration of alcohol in arterial blood is higher than in venous blood.
Breath tests reflect alcohol concentration in the pulmonary artery.
The breathalyzer also can react with acetone (as found in 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 readout. Prints out a card for a permanent record.

47. Breath Testers
Breath testers that operate on the principle of infrared light absorption are becoming increasingly popular within the law enforcement community.

48. Breath Testers
Many types of breath testers are designed to analyze a set volume of breath.
The captured breath is exposed to infrared light.
Can be built into cars.
Car can’t start if drunk.

49. Field Testing
A portable, handheld, roadside breath tester may be used to determine a preliminary breath-alcohol content.

50. Gas Chromatography Testing
Gas chromatography offers the toxicologist the most widely used approach for determining alcohol levels in blood.

51. Drunk Driver Kills Cyclist

52. Toxicology of Alcohol
The analysis of alcohol exemplifies the primary objective of forensic toxicology—the detection and isolation of drugs in the body for the purpose of determining their influence on human behavior.
Alcohol, or ethyl alcohol, is a colorless liquid normally diluted with water and consumed as a beverage.

53. Alcohol Levels
Experimental evidence has verified that the amount of alcohol exhaled in the breath is in direct proportion to the blood concentration.

54. Alcohol and Law
The American Medical Association and the National Safety Council have been able to exert considerable influence in convincing the states to establish uniform and reasonable blood-alcohol standards.
Between 1939 and 1964 a person having a blood-alcohol level in excess of 0.15 percent w/v was to be considered under the influence, which was lowered to 0.10 percent by 1965.

55. Alcohol and Law
In 1972 the impairment level was recommended to be lowered again to 0.08 percent w/v.
Starting in 2003, states adopted the 0.08 percent
Commercial drivers are allowed only 0.04% because of the possible dangers of driving large and hazardous payloads.

56. Alcohol and Law
To prevent a person’s refusal to take a test for alcohol consumption, the National Highway Traffic Safety Administration recommended an “implied consent” law.
Adopted by all states by 1973, 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 for a test for alcohol intoxication if requested or be subject to loss of the license.