Forensics: Poison

What is a poison?
A poison is a substance that can cause disturbances to organisms, usually by a chemical reaction, when a sufficient quantity is  consumed by that organism.

Some common sources of poison:
-Medicine (overdose of prescriptions, etc..)
-Bites (venom from snakes, spiders, etc..)
-Food (rotten/raw, allergies )

-Household Products (ammonia)

-Plants (Poison Ivy)

-Carbon Monoxide

-Lead

Signs of Poisons:

-Foaming/Drooling

-Rash/Bruising

-Excess Vomit

-Increased Heart Rate/ Breathing

-Enlarged Pupils 

-Busted Blood Vessels (Bleeding under skin) 

- Discoloration to skin.

Lab: 

For the lab we were asked to identify which substance was a certain poison out of several unknowns, with the help of various reagents. 

1. Metal Poisons: 

Information given:

      1- Chromium would turn orange when acidified. 

      2- Lead forms a yellow precipitate when KI is added.

      3- Iron turns red (blood red) when KSCN is added.

Results: 

Unknown 1:  Lead (Pb) 

Unknown 2: Iron (Fe) 

Unknown 3: Chromium (Cr)

2. Sugars:
Information given: A purple color should form when sugar is present in the unknown.
Results:
Unknown 1: Negative
Unknown 2: Negative
Unknown 3: Negative

3. Household Ammonia:
Information given:
      1- Odor present
      2- pH over 7 (basic)
      3- Phenolthaline is pink/purple in solution (solution is basic)
Results:
Unknown 1: Negative
Unknown 2: Positive for all three test.
Unknown 3: Negative

4. Aspirin:
Information given:
     1-Bromythymel Blue will be yellow (acidic)
     2- pH is below 7. (acidic)
Results:
Unknown 1: Bromythymel blue turned the solution yellow. pH was 2. (acidic)
Unknown 2:  Negative. pH of 8.
Unknown 3:  Negative. pH of 8.

5. Cyanide:
Information given: Solution turns blood red when Fe+3 is added

6. Iodine:
Information given: Turn a blue/black color when starch is added.
Results:
Unknown 1: Negative. (remained yellow)
Unknown 2: Negative. (remained red)
Unknown 3: Positive. Solution turned blue.