Due to the need for a comprehensive listing of toxic ceramic materials
on the Net, I have put together information on this subject. Below
you will find a listing of 35 common and not so common ceramic ingredients
-- the stuff that we deal with on a daily basis. While most of this
knowledge is freely available, my experience at various art schools
has told me that the toxicity of ceramic materials is not stressed
enough. Even well known figures in the ceramic world have been known
to disregard common sense rules. One well-known tragic incident
was Hans Copers death from manganese poisoning. The instances of
emphesemia due to dust inhalation amongst potters is too high --
a sickness which is fairly easily avoided. I hope this list will
contribute to the knowledge available on ceramic toxins on the Net.
Many substances are a problem for the potter during production,
e.g. through touch or inhalation, others in the finished product.
designates a substance which may be hazardous to health, either
through inhalation or assimilation through the skin. Some substances
should not be used for tableware, usually due to leaching. While
the substaces listed may be hazardous, this does not mean they cannot
be used at all - rather that caution should be used! Note that some
ingredients listed may not be designated as toxic, but may be hazardous
nonetheless. To make a contribution to this database, please send
A comprehensive list of MSDS (Material Safety Data Sheets) is available
||dust is a nuisance to lungs
||causes particularly nasty, incurable fibrosis
if inhaled. More
|is a dangerous form of barium, as it forms
a soluble chloride in the stomach and accumulates. It affects
muscles, in particular the heart, increasing its excitability,
leading to high blood pressure and internal bleeding. Will penetrate
the skin. Not recommended for food ware, as it may leach.
See Feature Article for more
||chronic exposure can cause asthma, diarrhoea
and skin conditions
| Used as a pigment in glazes.
Can cause respiratory diseases, osteoporosis, cancer and other
problems. See Feature Article for more
|If the oxygen level falls, hearing will decrease,
pulse and blood pressure rise. Carbon dioxide forms during combustion
|combines in the body with the haemoglobin
in the blood and reduces the availability of oxygen to the body.
Symptoms such as headache, dizziness and fatigue appear in healthy
people when 10% of their haemoglobin combines with carbon monoxide.
Can lead very quickly to drowsiness, then death. Forms during
heavy reduction firings. More
|Chromates and Chromic Acid
|may be cancerous. Will also enter the body
through the skin.
See Feature Article for mor information.
|Cobalt Oxide, Carbonate
|can cause liver damage and dermatitis. Will
enter the body through the skin.
|salts are irritants to the skin, eyes,and
mucous membranes. Inhalation of copper dust and fume results
in irritation of the respiratory tract. See Feature
Article for more information.
||in all forms in the studio should be avoided.
They accumulate over the years and cause emphesemia -- not a
nice disease to have. Take special care with silica.
|can be fatal and should be avoided.
||especially in the fired state can shed invisible
floating fibres that have similar effects to asbestos.
||from salt kilns and reducing kilns, can cause
respiration trouble or even acid corrosion of lung tissue.
||may cause asthma and eye inflammations.
|may lead to acute pneumonia and cause lung
|Iron Oxide Dust
||is poisonous for children and can cause "iron
pigmentation" of the lungs, supposedly benign but contentious.
||similar to silica.
|is an accumulative poison. It can be stored
in the bone structure for years before a fatal dose is accumulated.
Beware of raw lead froms, such as white or yello lead, which
are extremely toxic. Use lead frits instead. Do not use for
|Liquid Petroleum Gas
||can cause headaches, numbness, chills and
vomiting, but is a greater risk as explosive than inhalation.
||is considered inoxious, but general
rules for dusts still apply.
||can lead to brain damage and eventually death.
Will penetrate skin.
See Feature Article for mor information.
|Mica, Muscovite, Vermiculite, Lipidolite
||may contain traces of asbestos.
Inhalation of dust will lead to lung irritation and coughing,
possibly cancer, pneumoconiosis, dyspnea.
||can cause cancer. Will cause skin irritation
('nickel itch'). Will penetrate skin.
||may cause asthma.
|Potassium Dichromate/ Bichromate
|is very poisonous. Can cause kidney
failure and is cancerous. Avoid all contact! Not recommended
||affects the liver.
||is everpresent in clay materials. Repeated
inhalation will cause potentially fatal silicosis, or 'potters'
asthma', a form of emphesemia. The molecule (especially when
fired) has a 'hook' which attaches itself to the lung wall and
accumulates and irritates.
||is a strong lung irritant and can
form when firing soluble metal salts.
||similar to silica
||can result in 'stannosis', supposedly a benign condition.
||causes pulmonary irritation in chronically
exposed workers. More
||cause kidney damage, not to mention
||can cause Anemia; it a respiratory irritant. See Feature
Article for more info. More info also here.
||primarily a nuisance dust, but exposures to high concentrations
can result in respiratory system effects. More
||contact of the skin with zirconium or zirconium
compounds has caused skin granulomas in the form of linear streaks
of small papules; also causes pulmonary granulomas after prolonged