Download - Forensic science TOXICOLOGY AND ALCOHOL
FORENSIC SCIENCETOXICOLOGY AND
ALCOHOLThe study of Poisons and how they affect the human body.
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ToxicologyToxicology—the study of the adverse
effects of chemicals or physical agents on living organisms… PoisonsTypes:
Environmental—air, water, soilConsumer—foods, cosmetics, drugsMedical, clinical, forensic
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.
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Forensic ToxicologyPostmortem—medical examiner or coroner
Criminal—motor vehicle accidents (MVA)
Workplace—drug testing
Sports—human and animal
Environment—industrial, catastrophic, terrorism
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ToxicologyToxic substances may:
Be a cause of deathContribute to deathCause impairmentExplain behavior
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Aspects of ToxicityDosage – Has 5 factors:The chemical or physical form of the
substanceThe mode of entry into the bodyBody weight and physiological conditions
of the victim, including age and sexThe time period of exposureThe presence of other chemicals in the
body or in the dose
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Lethal DoseLD50 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
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Toxicity ClassificationLD50 (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
Link to LD 50 table
World’s Worst Industrial Accident: Bopal IndiaIn 1984 at the Union Carbide India pesticide plant in Bhopal,. Over 500,000 people were exposed to methyl isocyanate gas and other chemicals. The toxic substance made its way in and around the shanty towns located near the plant. The government of India confirmed a total of 3,787 deaths related to the gas release.[3] Others estimate 8,000 died within two weeks and another 8,000 or more have since died from gas-related diseasesVideo
What is the World’s Deadliest Snake?
The deadliest snake is a Belcher's Sea-snake. It takes only 0.02 milligrams of venom to kill a person. They usually injects around 35 milligrams and that can kill around 15,000 people with one bite. Death can happen within 2 minutes.
Where are more people killed by Snakes?
An estimated 12,000 people die annually from Cobra bites in India. It is possible that under the right conditions a person could die from a cobra bite in 30 minutes
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Symptoms of Various Types of PoisoningSymptom/EvidenceCharacteristic burns around the lips and mouth of victimRed or pink patches on the chest andthigh, unusually bright red lividityBlack vomitGreenish-brown vomitYellow vomitCoffee-brown vomit, onion or garlic odorBurnt almond odorExtreme diarrheaNausea and vomiting, unconsciousnesspossibly blindness
Type of PoisonCaustic poison
(lye)
Carbon monoxide
Sulfuric acidHydrochloric acidNitric acidPhosphorusCyanideArsenic, mercuryMethyl (wood) or
isopropyl(rubbing) alcohol
Famous PoisonsHemlock 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.
Famous PoisonsArsenic 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.
Famous PoisonsIf 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!
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.
Famous Poisons
Famous Poisons
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.
MERCURY
Famous PoisonsThe 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.
Belladonna
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To Prove a Case of PoisoningProve a crime was committed:
1. Motive ?
2. Intent?
3. Access to poison?
4 Access to victim?
5. Death was homicidal?
6. Death was caused by poison?
Pattern of poisoningChemical 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.
POISONING IN CHILDRENPoison 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 over dosage of drugs by the parents or by the medical staff is also frequent.
Accidental PoisoningAccidental 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.
Acute or Chronic ExposureAcute 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
Carbon MonoxideCarbon 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.
TOXICOLOGY OF ALCOHOL
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Alcohol—Ethyl Alcohol (C2H5OH)
Most abused drug in AmericaAbout 40 percent of all traffic deaths are alcohol-
relatedToxic—affecting the central nervous system,
Acts as a depressant, especially the brain. Colorless liquid, generally diluted in waterAlcohol appears in blood within minutes of
consumption; 30–90 minutes for full absorptionDetoxification—about 90 percent in the liverAbout 5 percent is excreted unchanged in breath,
perspiration, and urine
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.
Alcohol Effects upon the bodyAs can be seen, the effects of alcohol upon the body are not good. With repeated exposure, general health declines.
Alcohol Breaks down to AcetaldehydeIn 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
ALCOHOL-INDUCED FATTY LIVER
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.
• Estimated costs of alcohol related crashes in 2000 were over $114 b ($51 billion in monetary costs, $63 b in quality of life losses)
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.
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Rate of AbsorptionDepends on:
Amount of alcohol consumed
The alcohol content ofthe beverage
Time taken to consume itQuantity and type of food
present in the stomachPhysiology of the consumer
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BAC: Blood Alcohol ContentExpressed 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
BAC Calculation
MaleBAC =
FemaleBAC =
Your liver oxidizes alcohol to filter it out of the body. This Burn-off rate is 0.0015 percent per hour, (but can vary)Healthy liver metabolizes about0.5 oz = 15 ml of alcohol per hour
0.071 (oz) (% alcohol) body weight
0.085 (oz) (% alcohol) body weight
What's a "standard" drink?
12 fl oz of
regular beer
=8-9 fl oz of
malt liquor(shown in a 12-oz glass)
=5 fl oz oftable wine
=3-4 oz offortified wine(such as sherry or port; 3.5
oz shown)
=2-3 oz ofcordial, liqueur,
or aperitif(2.5 oz shown)
=1.5 oz ofbrandy(a single jigger or
shot)
=1.5 fl oz
shot of
80-proo
f spiri
ts("har
d liquor
")
Many people are surprised to learn what counts as a drink. In the United States, a "standard" drink is any drink that contains about 0.6 fluid ounces or 14 grams of "pure" alcohol. Although the drinks below are different sizes, each contains approximately the same amount of alcohol and counts as a single standard drink.
BLOOD ALCOHOL LEGAL LIMITS
Legal maximum BAC in USA is.08% or 0.8 grams/kilogram• 1 beer = 0.6 oz alcohol = 14 grams• 150 lb adult = 68 kg• 63% body weight from blood = 42.8 kg• 14/42800 = 0.000327or 0.327 grams/kg or .0327%• 2.5 beers produces BAC of about 0.083%
BLOOD ALCOHOL CONCENTRATIONS
.020 - light to moderate drinkers begin to feel some effects* .040 - most people begin to feel relaxed* .060 - judgment is somewhat impaired, people are less able to make rationaldecisions about their capabilities (for example, driving)* .080 - there is a definite impairment of muscle coordination and driving skills;this is legal level for intoxication in all states* .10 - there is a clear deterioration of reaction time and control; this is legallydrunk in most states* .120 - vomiting usually occurs. Unless this level is reached slowly or a personhas developed a tolerance to alcohol* .150 - balance and movement are impaired. This blood-alcohol level meansthe equivalent of 1/2 pint of whiskey is circulating in the blood stream* .300 - many people lose consciousness* .400 - most people lose consciousness; some die* .450 - breathing stops; this is a fatal dose for most people
BLOOD ALCOHOL CHART
WHAT IS BLOOD ALCOHOL CONCENTRATION:
What is blood alcohol concentration?• Ratio of amount of alcohol in the blood to the amount of blood.• 1 gram of alcohol per kilogram of blood is a ratio of 1/1000 or 0.001 alcohol/blood.• 0.001 alcohol/blood concentration is 0.10%
://health.discovery.com/tools/calculators/alcohol/alcohol.html
BLOOD ALCOHOL CALCULATOR
HOW MANY DRINKS IN DIFFERENT EXAMPLES?
Regular Beer (5%)
Malt Liquor (7%)
Table Wine (12%)
80 proof liquor
12 fl oz = 1 oz 12 fl oz = 1/5 oz 750 ml bottle = A shot (50ml or 1.5 oz = 1
16 fl oz = 1.3 16 = 2 5 drinks 200 ml (half pint) =4.5 22 fl oz = 2 22 fl oz = 2.5 375 ml (pint) = 8.5
drinks40 fl oz = 3.5 40 fl oz = 4.5 750 ml (a fifth) = 17
In the United States, a "standard" drink is any drink that contains about 0.6 fluid ounces or 14 grams of "pure" alcohol. Below is the approximate number of standard drinks in different sized containers of
NOW YOUR TURNFind the BAC for a 255-lb man who, in 2 hours, has drunk 13 beers. (Assume that each beer is 12 oz with a 4.5% alcohol content.) Round your answer to the nearest thousandth.
SOLUTIONBAC = 0.071 (oz) (% alcohol)
body weight
BAC = 0.071 x 12 oz x 13 beers x 4.5% 255 lbs
= 0.19%
Alcohol Levels• Experimental
evidence has verified that the amount of alcohol exhaled in the breath is in direct proportion to the blood concentration.
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.
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Field TestsPreliminary 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
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.
Modern Breath Testers• Breath testers that operate on the
principle of infrared light absorption are becoming increasingly popular within the law enforcement community.
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BreathalyzerOne of the first breathalyzers used chemical
reactions to measure alcohol in field. Collects and measures alcohol content
of alveolar breathBreath sample mixes with 3 ml of 0.025 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.
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GeneralizationsDuring 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.
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.
Field Testing• A portable, handheld, roadside
breath tester may be used to determine a preliminary breath-alcohol content.
Gas Chromatography Testing• Gas chromatography offers the
toxicologist the most widely used approach for determining alcohol levels in blood.
DRUNK DRIVER KILLS CYCLIST
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.
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.
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.