There are potters who suggest the use of Sodium Azide as a biocide in slips and gums.
"Depending on time, temperature, pH, gum can be attacked by microbes or molds. If this happens store in a cooler place, make smaller batches, adjust the pH to make a less friendly environment, or add an antiseptic i.e. NaN3
I put sodium azide in my CMC solutions - just a tiny pinch, less than 0.5% stops bacteria cold turkey". (Clayart, 2004)
We disagree with the use of this chemical for the following reasons :
Sodium azide
:
An azide is a compound of hydrogen or a
metal ion and the monovalent -N3 radical.
Sodium azide is used in protection
airbags of cars and this use has increased a lot its production.
In small amounts it is used in biology labs as an antimicrobial in
reagents.
I-Experimental
Toxicology :
In animals it is a poison by ingestion,
skin contact, intraperitoneal, intraveinous, and subcutaneous
routes.
II-Human Toxicology
:
The lowest toxic dose by ingestion is 5
mg.
A-Routes of Entry :
-Ingestion,
-Inhalation,
-Skin
B-Ingestion :
1-Peripheral vasodilatation :
rapidly causing a drop in the blood
pressure :
-vertigo,
-a tendancy to loose consciousness,
-palpitations,
-sweating,
-headaches
2-Severe cases :
Cardiovascular collapsus.
3-Cardiac Ischaemic Symptoms
:
If the amount ingested is large, cardiac
ischaemic symptoms and signs may occur ( 80 mg).
4-Severe Acute Intoxication (Suicide)
:
-coma (brain oedema),
-collapsus,
-cardiac arythmias,
-metabolic acidosis,
-respiratory depression,
-pulmonary oedema.
Treatment :
There is no known treatment.
C-Inhalation :
In a study among workers exposed to
airborne sodium azide, most suffered from :
-headaches,
-periods of hypotension
-palpitations.
Two workers exposed to large amounts of
this chemical suffered from :
Reacts with heavy metals to form
dangerously explosive heavy metal azides, a particular problem in
laboratory equipment and drain traps Sodium azide " per se " can
be an explosion danger, following a shock or when heated
rapidly
Many azides are poisonous, and cause a
fall in blood pressure, and some inhibit enzyme action, thus
resembling nitrites and cyanides.
All azide salts and the acid are
unstable and some decompose explosively, altough lead azide, which
is one of the most important azides, is not very sensitive.
Hazardous Decomposition :
When heated to decomposition they emit
highly toxic fumes.
Explosiveness :
Schock and heat will explode
them.
If exposed to CS2, they form violently
explosive salts.