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Alumina Toxicology | Ammonia and Latex Toxicity | Antimony Oxide | Arsenic Oxide | Asbestos: A Difficult-to-Repace Material | Ball Clay | BARIUM and COMPOUNDS / Toxicology | Barium Carbonate | Bentonite Toxicity | Beryllium Monoxide Toxicology | Bismuth Trioxide Toxicology | Boron Compounds and Their Toxicity | Brown Stain | Cadmium Toxicity | Calcium Carbonate Toxicology | Carbon Monoxide Toxicity | Cesium Toxicology | Chromium Compounds Toxicology | Cobalt Oxide and Carbonate | Cobalt Toxicology | Copper Compounds Toxicology | Copper Oxide and Carbonate | Cristobalite Toxicity | Cryolite and Ceramics | Dealing With Dust in Ceramics | Diatomaceous Earth Toxicology | Dioxins in Clays | Epsom Salts | Eye Injuries Due to Radiation | Feldspar | Fighting Micro-Organisms in Ceramics | Fluorine Gas | Gallium Oxide Toxicology | Hafnium Oxide Toxicty | Hydrofluoric Acid Toxicity | Iron oxide and Hematite | Kaolin Toxicity | Lead Chromate | Lead in Ceramic Glazes: What Did We Learn? | Lead in Frits: The Hazards | Lead Toxicology | Lithium Carbonate Toxicity | Lithium Toxicology | Man-Made Vitreous Fibers (MMVF) Toxicology | Man-Made Vitreous Fibers Safety Update | Manganese and Parkinsons by Jane Watkins | Manganese in Clay Bodies | Manganese Inorganic Compounds Toxicology | Manganese Toxicity by Elke Blodgett | Manganese: Creativity and Illness by Dierdre O'Reilly | Molybdenum Compounds Toxicology | Nickel Compounds Toxicity | Niobium Oxide Toxicity | Occupational Dermatoses | Overview of Material Safety by Gavin Stairs | Paraffin Toxicology | Perlite Toxicity | Plant Ash Toxicity | Potassium Carbonate Toxicity | Pregnancy and Ceramics | Propane Toxicology | Quartz Toxicity | Quartz Toxicity on Clayart | Rare Earth Compounds Toxicity | Rubidium and Cesium Toxicology | Rutile Toxicology | Silicosis and Screening | Silver Compounds Toxicology | Sodium Azide Toxicology | Sodium Carbonate Toxicology | Sodium Silicate Powder Toxicology | Stannous Chloride Toxicity | Strontium Carbonate Toxicity Note | Sulfur Dioxide Toxicity | Talc Hazards Overview | Talc Toxicology | Thallium Oxide Toxicology | The Use of Barium in Clay Bodies | Thorium Dioxide Toxicity | Tin Inorganic Compounds | Titanium Dioxide Toxicology | Toxicological Assessment of Zeolites | Tungsten Compounds Toxicology | Understanding Acronyms on MSDS's | Uranium and Ceramics | Vanadium and Compounds Toxicology | Zinc Compounds Toxicology | Zirconium Compounds Toxicity | Zirconium Encapsulated Stains Toxicity

Quartz Toxicity

Quartz, silica, crystalline silica and flint are non-toxic materials having no known adverse health effects from ingestion. However, it does pose considerable hazards with respect to long term inhalation.

CAS: 14808-60-7 Silica: ACGIH TLV & OSHA PEL: 0.1 mg/cubic meter 8 hr. TWA, Respirable Dust. By comparison iron oxide is considered a safe-to-use material at a TLV of 5.0, kaolin is 2.0, barium carbonate is 0.5, quartz is 0.1-0.05.

Silica is contained in many ceramic minerals (e.g. feldspar), including its pure form of flint. Inhalation over long periods will cause silicosis where fibrosis of the lungs causes shortness of breath and can lead to death in severe cases. Over exposure to silica weakens the body's defense mechanisms.

Because of the abundance of silica, potential hazards are widespread. NIOSH in the US has estimated that 3.2 million workers in the USA are exposed to silica dust. Industries affected are quarrying, mining, steel, iron, metal foundries, abrasive blasting, construction, glass and ceramics, paint and pigments, granite and stone industries.

The primary health risk is the inhalation of "respirable" particles smaller than 10 micrometers (about 1/2500th of an inch). Generally, the smaller the particles are, the greater hazard and potential injury to the lungs. Dust particles larger than these are not capable of penetrating the defense mechanisms of the lung. Prolonged exposure may cause delayed chronic lung disease-silicosis. Chronic silicosis may take many years of exposure to develop, but with acute exposure rapid development can occur. In latter stages of silicosis, known as complicated or conglomerate silicosis, lung function may be reduced, resulting in symptoms of shortness of breath.

Quartz rock can be calcined so that it breaks down and grinds much easier. When this is done the material poses a much greater health risk.

The International Agency for Research on Cancer (IARC) has determined from a review of human epidemiology studies that there is limited evidence for the carcinogenicity of crystalline silica.

In the USA, occupational exposure is regulated by OSHA and under the laws of some states. The mining industry is regulated by the Mine Safety and Health Administration (MSHA). In 1992 the permissible exposure limit based on an 8-hour time weighted average concentration of respirable silica is .1 milligrams of quartz per cubic meter of air. OSHA and ASTM agree on this figure.

Studies have been somewhat mixed in results, even where when confounding exposures of other carcinogens including radon and tobacco are involved.

Findings on cancer risks associated with silica dust have made it necessary in some states that material safety data sheets reference the findings of IARC.

Silica can be used and handled safely with appropriate work practices and the avoidance of prolonged exposure. Dust concentrations past the limit are invisible to the naked eye, so employers must monitor workers using approved sampling methods.

See Crystalline Silica Q&A from National Industrial Sand Association, 900 Spring Street, Silver Spring, MD 20910. See The American Ceramic Society Bulletin Aug 2000 Page 60 for information on the Crystalline Silica Work Group of ACerS.

Related Information

Health warning phrases on a bag of ground silica

N95 Particulate Respirator mask

This designation is an international standard for a general purpose respirator to filter out respirable quartz particles (which cause silicosis). Use one of these when working in a area where ventilation is insufficient to remove all of the dust. Use it also in circumstances where there is temporary generation of large quantities of dust. Do not wear this as a substitute for keeping floors and working areas clean.


Materials Kaolin 143
Materials Kaolin 115
Materials Kaolin 114
Materials Kaolin 113
Materials Kaolin 111
Materials Feldspar 661
Materials Feldspar 645
Materials Feldspar 635
Materials Feldspar 632
Materials Clay 261
Materials Clay 246
Materials 3380 Ball Clay
Materials JASS Ball Clay
Materials CTS Ball Clay
Materials SB Ball Clay
Materials Kaolin 151
Materials Kaolin 171
Materials Quartz 741
Materials Crystalline Silica
Materials Edgar Glass Sand
Materials Sil-o-spar
Materials Flint Pebbles
Materials Quartz 762
Materials Quartz 761
Materials OSML Ball Clay
Materials MB Ball Clay
Materials HA-5 Ball Clay
Materials Clay 220
Materials Clay 216
Materials Clay 215
Materials Clay 220
Materials Silica
Materials PV Clay
Materials Quartz
Materials Primas FA-200 Feldspar
Materials Fireclay
Materials Goldart
Materials C-1 Clay
Materials Min-U-Sil 40
Materials Alberta Slip
Materials Hymod Blue
Materials Clay 232
Materials Clay 222
Materials Flint
Materials Clay 244
Materials J-4 Ball Clay
Materials Imco 400 Fireclay
Materials Hyplas 64 Ball Clay
Materials Hyplas 71 Ball Clay
Materials Hymod KC
Materials Hymod AT Ball Clay
Materials APG Missouri Fireclay
Materials #1 Q-Rok
Materials NAT Dry Milled Fireclay
Materials Big Horn CE 200 Bentonite
Materials Bentonite
Materials Hymod Prima
Materials 49'er Ball Clay
Materials Novacite Silica 1
Materials Clay 233
Glossary Respirable Crystalline Silica
The breathing of respirable quartz particles is a hazard in ceramic ware manufacture and hobby. These particles are of a size that can catch deep in the air sacks of the lungs.
Hazards Bentonite Toxicity
Hazards Feldspar
Hazards Quartz Toxicity on Clayart
Quartz is one of the most dangerous materials used in ceramics, yet it is irreplaceable. It is the most abundant mineral on earth, we must learn to use it safely.
Hazards Ball Clay
Projects Hazards
Quartz on WikiPedia
Quartz MSDS at

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