Transcript 10.1 Notes - Trimble County Schools

Chapter 10
10.1
Forensic Toxicology
Objectives

Explain how alcohol is absorbed into the
bloodstream, transported throughout the body,
and eliminated by oxidation and excretion.
Alcohol
The most heavily abused drug in the
US
 40% traffic deaths (17,500) are
alcohol related
 Hospital treatment exceeds 2,000,000
persons per year

Toxicologists


Responsible for detecting and identifying
the presence of drugs and poisons in body
fluids, tissues, and organs
Services used in crime labs, medical
examiner’s offices, and hospitals


Various systems exist across the country
Role limited to matters that pertain to
violations of criminal law
Toxicology of Alcohol
Ethyl alcohol is a colorless liquid
diluted with water
 Logically most obvious measure of
intoxication would be amount of
liquor consumed but such information
is not normally available to law
enforcement

 many
factors influence
intoxication level - i.e. body
weight, rate of alcohol
absorption in body
 Alcohol is a depressant,
primarily effecting the central
nervous system and brain

Effect is proportional to concentration
of alcohol in nerve cells
Most susceptible areas = forebrain
 Later functions of central and rear brain
affected
 Most resistant and last to fail is brain’s
medulla

 Regulates
vital functions of respiration and
heart activity
 Toxicologists
focus attention on
concentration in blood as blood
provides the medium for
circulation of alcohol through the
body
 Blood
alcohol levels are directly
proportional to the concentration in
the brain
 Alcohol
appears in blood
moments after consumed
 Concentration
increases as alcohol
is absorbed from stomach and
small intestine into blood stream
Rate of alcohol absorption into
the bloodstream depends on:
A.
B.
C.
D.
Time taken to consume the drink
Alcohol content of the beverage
Amount consumed
Quantity and type of food consumed at
the time of drinking
Absorption process completed usually
30-90 minutes after final drink
 Absorption process is difficult to
predict
 Alcohol enters blood and is carried to
all parts of the body


Distributed uniformly in water portions
of body
 Low
content in fat, bones, and hair
 Post-mortem
examinations use
water-rich organs and fluids to
determine alcohol content
 Brain,
humor
cerebrospinal fluid, vitreous
10.1 Questions – answer on a
sheet of notebook paper
1.
2.
3.
4.
5.
6.
What is the most widely abused drug in Western
countries?
What is a toxicologist?
Name three settings in which a toxicologist often
works.
Name at least three factors that influence the rate at
which alcohol is absorbed into the bloodstream.
In what parts of the body does alcohol tend to
accumulate?
Why does it accumulate in these places?