*
Toxicology Lab Activity
* Identify some common over-the-counter drugs
* Note: The actual drugs will be used for these
tests
* Learn how to test for some “controlled drugs”
* Note:
Simulations will be used for the controlled
drugs. Substances that will act the same way for
a test will be substituted for the actual drug.
* Test for heavy metals (lead and mercury)
*
* Drug: any substance used as a medicine
internally or externally
* Narcotics: drugs that are habit forming
* Usually relieve pain, induce sleep, or cause
death when taken in excess
* Regulated by Federal law—i.e. Controlled drugs
* A drug is considered a poison if when taken in
excessive amounts it causes illness or death
*
* Search for evidence of drug or poison use:
* Empty glasses or bottles
* Medicine containers
* Traces of powder or liquids on the body, clothes,
carpet or floor
* Note: it is always easier to test an empty
container for traces of poison than a body
*
* Chromatography
* Spectrophotometry
* Mass spectrometry
* Spot tests with chemical reagents
* Note: We will use the last test in this lab
*
* Over-the-counter drugs can cause accidental
poisonings
* Examples
* Alcohol
* Antacids
* Nicotine
* Aspirin
*
* Aspirin = acetylsalicylic acid
* Ferric nitrate is used to test for the presence of
aspirin. When mixed, the aspirin hydrolyzes to
form salicylic acid and acetic acid. The ferric
ion reacts with the salicylic acid to form a
purple colored compound that is easily
identified.
* Acetaminophen = Tylenol
* Relieves pain without being acidic
*
* Alka-Seltzer
* Contains sodium bicarbonate, citric acid and a
very small amount of aspirin. Reacts with water
to produce carbon dioxide gas and a buffer.
* Sodium bicarbonate
* Reacts to neutralize stomach acid according to
the following equation:
NaHCO3 + HCl
NaCl + H2O
+ CO2
*
* Stop: Do Experiment #1
*
* Hallucinogenic Drugs = LSD, Marijuana,
Heroine, Cocaine.
* Most are white powder alkaloids (nitrogen
containing plant products having marked
physiological action when given to animals)
* Most are identified by the colored precipitates
they form with specific reagents.
* Most will also fluoresce under UV light
*
* LSD = Lysergic Acid Diethylamide
* Alkaloid from ergot (a fungus found on rye and
cereal)
* Can be made synthetically
* 50 micrograms taken orally produces psychosis
and brain disturbances.
* Will fluoresce under UV light
* Will form a yellow precipitate with potassium
chromate
*
* Marijuana = Cannabis sativa
* Only mind-bender that does not contain nitrogen
* Most widely used illegal drug
* Visual identification under a microscope reveals
small crystals of calcium carbonate at the base
of the leaf hairs.
* HCl will bubble and produce carbon dioxide gas
when dropped on a leaf
*
* Stop:
Do Experiment #2
*
* Poisons in general withhold the oxygen
necessary for life processes to continue from
the tissues.
* Various sources exist in the environment:
* Car exhaust
* Pesticides
* Medicines
* Industrial wastes
*
* Lead: found in batteries, paint, gasoline,
ceramic glazes, among others
* Affects the functioning of the blood, liver,
kidneys and brain
* Dose of 0.5 g can be fatal
* Lead will form a yellow precipitate when
mixed with potassium chromate
*
* Mercury: found in electric apparatuses,
thermometers, batteries, medicines, fungicides
for seeds, industrial waste and contaminated
fish.
* Affects brain tissues and destroys the neurons.
* Causes blindness, convulsions, mental
retardation and death
* Dose of 1g is fatal
*
* Stop: Do Experiment #3
*