Toxicology: Poisons
Toxicology – the study of the _______________ _____________________ of
________________ or _______________ agents on living organisms.
Types:
Environmental - ________________, water, ___________________
_______________________________- foods, cosmetics, drugs
- Medical, clinical, forensic
Forensic Toxicology
Postmortem – medical examiner or coroner
Criminal – motor vehicle accidents (_____________________)
Workplace – drug testing
Sports - _______________________________ and animal
Environment – industrial, ___________________________, terrorism
Toxicology
Toxic substances may: - Be a cause of death
- Contribute to _____________________
- Cause impairment
- Explain _____________________
Aspects of Toxicity
- __________
- The ______________ or _____________ form of the substance
- The_______________of entry into the ______________________
- ___________________ _______________ and physiological conditions of the victim,
including _________ and ____________
- The ___________________ period of exposure
- The presence of other chemicals in the body or in the dose
Lethal Dose
LD50 – refers to the dose of a ____________________ that _________
test population, ususally within ________________hours
Expressed in milligrams of substance per kilogram of body weight
Toxicity Classes
_________ the
Federal Regulatory Agencies
- ___________________ and ___________________ Administration (FDA)
- Environmental Protection Agency (EPA)
- Consumer ___________________ __________________ Commission
- Department of Transportation (DOT)
- _______________________ __________________ and Health Administration
(OSHA)
Symptoms of Various Types of Poisoning
Type of Poison
Caustic Poison (Lye)
Symptom/Evidence
Characteristic burns around the lips and mouth of the
Victim
Carbon Monoxide
__________________ or _______________ patches on the
chest and thighs, unusually bright red lividity
Sulfuric Acid
________ __________
Hydrochloric Acid
Greenish-Brown vomit
Nitric Acid
Yellow Vomit
Phosphorous
Coffee brown vomit, _______ or _______ odor
Cyanide
Burnt almond odor
Arsenic, Mercury
Pronounced diarrhea
Methyl (wood) or
________________ and vomiting, unconsciousness,
Isopropyl (Rubbing) alcohol
possibly blindness
Critical Information on Poisons
 Form
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________________ color
Characteristic odor
Solubilty
________________
Common sources
Lethal Dose
Mechanism
Possible __________ of
Administration
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Symptoms resulting from an acute
_______________
Symptoms resulting from chronic
exposure
Disease states mimicked by poisoning
Notes relating to the ___________
Specimens from victim
Analytical detection methods
Known _________ levels
Notes pertinent to analysis of poison
List of cases in which _________ was
used

Time interval of onset of symptoms
To Prove a Case
 Prove a crime was committed
 ____________________________
 _____________________
 Access to _____________________
 Access to _________
 Death was caused by poison
 Death was __________
Forensic Autopsy
Look for:
 Irritated _____________________
 Characteristic _________________
 Mees lines – single transverse _____________________
_____________________ on _____________________
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
Human Specimens for Analysis
 Blood
 Liver tissue
 Urine
 Brain tissue
 Viterous ________ of _____
 __________ tissue
 Bile
 ________/_________
 Gastric Contents
Toxicology: Alcohol
Alcohol – Ethyl Alcohol (C2H5OH)
 Most abused drug in America
 About ____% of all traffic deaths are _________-related
 Toxic – affecting the ________ _________ _________, especially the brain
 Colorless liquid, generally diluted in water
 Acts as a depressant
 Alcohol appears in blood within minutes of ___________; 30 – 90 minutes for
full absorption
 _____________ - about 90% in the liver
 About 5% is excreted unchanged in breath, perspiration and urine
Rate of Absorption
Depends on:
- amount of alcohol consumed
- the _____________ content of the ____________
- time taken to consume it
- quantity and type of food present in the stomach
- physiology of the _______________
BAC : Blood Alcohol Content
 Expressed as percent _________________ per ________________ of blood
 Legal limits in all states is ________________%
 Parameters influencing BAC:
- Body __________________
- Alcoholic _____________________
- ___________________of beverages consumed
- Time between consumption
 Burn off rate of ___________% per _________ but can vary:
 Male
BAC male = 0.071 x (ox) x (% alcohol)
Body weight
 Female
BAC female = 0.085 x (oz) (% alcohol)
Body weight
HENRY’S LAW
 When a volatile chemical is dissolved in a liquid and is brought to
_____________________ with air, there is a fixed ratio between the
concentration of the volatile compound in the___________and its concentration
in the _____________; this ratio is _____________________ for a given
temperature. THEREFORE, the _____________________ of
_____________________in _____________________ is
_____________________ to that in the _____________________.
 This_________________ of ______________in the _____________________ to
_______________ in the alveolar _________________ 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.
FIELD TESTS
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Preliminary tests—used to determine the _________________ of suspect’s
_________________ _________________ and whether or not another test is
_________________.
Psychophysical tests—3 Basic Tests
o _______________ ______________ _____________ (HGN):
_____________ a pen or small flashlight, ______________ left to right
with one’s eyes. In general, wavering at _________________indicates
__________ __________.
o Nine Step walk and turn (WAT): _________________and
_________________ _________ or _________ simple instructions at
___________ ____________.
o One-leg stand (OLS): maintain _________________,
_________________ and _________________ __________ or
___________ simple instructions at __________ __________.
Breathalyzer
 More practical in the field
 ________________and ________________ alcohol content of
________________ breath
 Breath sample mixes with 3 ml of 0.025 % K2Cr2O7 in ________________
____________ and ________________
 2K2Cr2O7 + 3C 2H5OH + 8H 2SO4  2Cr2(SO4)3 + 2K2SO4 + 3CH3COOH
+ 11 H2O
 ________________ ________________ is yellow, as concentration
________________ its light absorption diminishes so the breathalyzer indirectly
measures alcohol concentration by measuring light absorption of potassium
dichromate ________________ and________________the ________________
with ________________
Generalizations
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During absorption, the concentration of alcohol in _______________ blood will
be _______________ than in _______________ blood.
_______________ tests reflect alcohol _______________ in the
_______________ _______________.
The _______________ also can react with _______________ (as found with
diabetics), acetaldehyde, methanol, isopropyl alcohol, and paraldehyde, but these
are _______________ and their _______________means the person is in serious
_______________ _______________.
Breathalyzers now use an infrared light absorption device with a digital read-out.
Prints out a card for a permanent record.