Talc Toxicology

Introduction

Talc as a pure chemical compound is a hydrous magnesium silicate, [Mg6 (Si8O20) (OH4)], that exists in sheetlike crystalline forms or as fibers. The purity and physical form of any sample depends on the source of the talc and on the minerals found in the ore body from which it is refined. Talc can exist in many forms and depending on the ore source in can be found in a pure form or mixed with asbestos or silica. Talc used in industrial settings can contain mixtures of silica, amphibole asbestos, tremolite, actinolite, and anthophyllite. Exposure to low-grade talc may give rise to talcosilicosis or talcoasbestosis, in which cases the disease will exhibit the features of silicosis or asbestosis, respectively.

Inhalation talc exposure can result in

• talco-asbestosis
• talco-silicosis
• pure talcosis

Talco-Asbestosis

Talco-asbestosis closely resembles asbestosis and is produced by crystalline talc, generally inhaled with asbestos fibers. Pathologic and radiographic abnormalities are virtually identical with those of asbestosis, including calcifications and malignant tumor formation.

Talc containing more than 1% asbestos is considered a human carcinogen.

Talco-Silicosis

The first form, talco-silicosis, is caused by talc mined with high-silica-content mineral. Findings in this form are identical with those of silicosis.

Pure Talcosis

This type of talc is less fibrogenic than the others.

Pure talcosis results from the inhalation of pure talc without contamination from other mineral sources. It is found in occupational and non-occupational settings associated with cosmetic use of talcum powder.

Excessive use of talcum powder, as well as the accidental aspiration of talc by infants, has been associated with diffuse irregular opacities throughout the upper or lower lung fields, focal fibrosis of the small airways, bronchiolitis, and extensive fibrosis with granuloma formation.

On tissue examination, fibrosis, foreign body granulomas, and multinucleated giant cells are seen.

Radiologic abnormalities include round or irregular opacities.

Physiologic pulmonary testing reveals normal, restrictive, or mixed restrictive and obstructive abnormalities in pulmonary function.

In animals pure talc induces a cytogenic rather than fibrogenic effect on the lungs.

Intravenous Form

The fourth form, due to intravenous administration of talc, is usually associated with abuse of oral medications and production of vascular granulomas manifested by consolidations, large nodules, and masses. Talcosis may also present as a granulomatous pneumonitis and give rise to a radiological appearance of sarcoidosis or miliary tuberculosis. Such foreign body granulomas are seen especially (but not only) in intravenous drug addicts as result of the injection of crushed talc-containing tablets.

Here are a few toxicologic data sheets made available to us by The Répertoire Toxicologique de la Commission de la Santé et Sécurité du Travail du Québec :

Fibrous Talc

Identification

Main Synonyms

French names

Talc (fibreux)
TALC FIBREUX

English names

Talc, fibrous
FIBROUS TALC

Use and Sources of Emission

Manufacture of pharmaceutical products, pharmaceutical product.

Hygiene and safety

• Appearance

Solid fibrous, white-gray, odourless

• Physical Properties

1. Physical State : Solid
2. Solubility in Water : 0.00 g/l at 20 °C
3. Melting Point : 0.00 °C
4. Boiling Point : 0.00 °C

• Inflammability and Explosiveness

Inflammability

This product is non flammable.

Prevention

• Reactivity

• Stability

This product is stable.

• Incompatibility

No known incompatibility.

• Products of Decomposition

Information nonavailable

• Handling

Avoid any contact with the skin. Wear suitable eye protection. In the case of insufficient ventilation, wear a suitable breathing apparatus.

• Storage

Store in an airtight container.

• Leaks

Collect in a hermetic container duly identified by using a suitable technique in order to prevent the contamination of the environment.

• Waste Disposal

Consult with the regional authority.

Toxicology

• Absorption

This product is absorbed by the respiratory tract.

• Chronic Effects

• pulmonary fibrosis
• pneumoconiosis
• ranulomatosis

Cancerogenic Effects

Cancerogenic to human beings.

First aid

In the event of inhalation of vapors or dust, bring the person into a ventilated place.

Quebec039;s Exposure Limit

• Valeur d039;exposition moyenne pondérée (VEMP)

1 Fiber/cm³ (Respirable)

• Notations

C1 : Cancerogenic effet demonstrated in human beings.

EM : The exposure to this substance must be reduced to a minimum.

Non Fibrous Talc (Pure)

Identification

CAS Number : 14807-96-6

Molecular Formula: H2Mg3O12Si₄

Main Synonyms

French names

Talc (non fibreux)
Poudre de talc
Talc

English Names

Talc, not fibrous
Cosmetic talc.

Comment

This product can contain quartz (<1%)

Uses and Sources of Emission

Adsorption agent, manufacture of pharmaceutical products.

Hygiene and safety

• Appearance

Powdery, white, odourless.

• Physical Properties

1. State : Solid
2. Molecular Mass : 379,3
3. Density : 2,7 g/ml at 20 °C
4. Solubility in Water : Insoluble
5. Fusion Point : 950 °C.

• Inflammability and Explosiveness

Inflammability: This product is non flammable.

Prevention

• Reactivity

• Stability

This product is stable.

• Incompatibility

No known incompatibility for this product.

• Decomposition Products

Information unavailable.

• Handling

Wear ocular protection, and in the case of insufficient ventilation, a suitable breathing apparatus.

• Storage

Preserve in an airtight container.

Preserve in a well ventilated place.

• Leaks

Collect wastes and put them in a dustbin.

• Waste disposal

Put in a dustbin.

Toxicology

• IDLH (Immediate danger to life and health)

1 000 mg/m³

• Absorption

This product is absorbed by the respiratory and digestive tracts.

• Acute Effects

• Possible irritation

• eyes
• skin
• respiratory tract (upper)

• Digestive tract

• nausea
• diarrhoea

• Chronic Effects

• cough
• benign pneumoconiosis
• possible pulmonary fibrosis and talcosis

Effects on Development

Several studies in several animal species suggest the absence of effects on antenatal development.

Effects on Reproduction

No data concerning the effects on reproduction were found in the consulted documentary sources.

Data on Mother039;s Milk

There is no data concerning its excretion or detection in milk.

Cancerogenic Effects

• Evaluation by the I.A.R.C.

It cannot be classified as for its cancerogenicity for man (group 3).

• Evaluation by the A.C.G.I.H.

Substance not classifiable as cancerogenic for man (A4 group).

Mutagenic effects

Several studies in animal species suggest the absence of a mutagenic effect.

First aid

• Ocular Contact

Rinse eyes with plenty of water and see a doctor. Wash skin with soap and water.

• Ingestion

Provoke vomiting if the patient is conscious.

• Inhalation

Bring the person into a ventilated place.

Quebec039;s exposure limit

Valeur d039;exposition moyenne pondérée (VEMP)

Respirable dust : 3 (mg/m³)

Massive Talc (Soapstone)

Identification

CAS Number : 14378-12-2

Molecular Formula : H2MG3O12SI4

Main Synonyms

French names

Stéatite
Pierre à savon

English names:

Soapstone

Massive talc

Uses and Sources of Emission

Soapstone is a steatite stone and its primary components are magnesite, dolomite, chlorite, and talc.

For thousands of years, soapstone has been used throughout the world for tools, karafes, vases, goblets, sculptures, fireplaces, etc.

In early American history, soapstone was used primarily for building blocks, sculpting and urns.

In early New England, Soapstone uses ranged fom fireplace hearths to countertops, sinks, and oven fireplace stoves.

Currently in the USA and in different parts of the world, soapstone is used for the largest variety of items ever yet - including balusters, stair treads, window sills and island tops.

For over one hundred years, soapstone sinks and tiles have been used in science class rooms and labs along with work tables and counter tops. Its longevity to long term - high traffic use is amazing!

Because of its truly remarkable and natural heat retention characteristics, soapstone is widely used for masonry heater fireplaces, wood stoves, fireplace liners and pizza ovens.

It is also used as a colourant.

Hygiene and safety

• Appearance

Powdery, white, odourless.

• Physical properties

1. Physical State : Solid
2. Molecular Mass : 379,2
3. Density : 2,75 g/ml at 20 °C
4. Solubility in Water : Insoluble.

• Inflammability and Explosiveness

Inflammability : This product is non flammable.

Prevention

• Reactivity

• Stability

This product is stable.

• Incompatibility

No known incompatibility for this product

• Products of Decomposition

Information non available

• Handling

Ventilate adequately if not wear a suitable breathing apparatus

• Leaks

Collect waste and put in a hermetic container.

• Waste disposal

Consult with the regional office of the Department of the Environment.

Toxicology

• IDLH (Immediate Danger to Life and Health)

3 000 mg/m³

• Absorption

This product is absorbed by the respiratory tract.

• Chronic Effects

Fibrotic pneumoconiosis

• cough
• dyspnea, shortness of breath
• cyanosis (blueing of extremities)
• deformity of the tips of the fingers (digital hippocratism)
• obstruction of the alveoli
• limitation of thoracic expansion
• possible heart failure

First aid

• Eyes

Rinse eyes with plenty of water.

• Inhalation

In the event of inhalation of vapors or dust, bring the person into a ventilated place.

If he does not breathe, give the artificial respiration.

Call a doctor.

Quebec039;s Exposure Limit

Valeur d039;Exposition Moyenne Pondérée (VEMP)

Respirable dust : 3 (mg/m³)

Total dust : 6 (mg/m³)

Note : The limit applies to dust not containing asbestos and in which the percentage of crystalline silica is lower than 1 %.

References

1. Occupational Medicine,Carl Zenz, last edition.
2. Clinical Environmental Health and Toxic Exposures, Sullivan & Krieger; last edition.
3. Sax039;s Dangerous Properties of Industrial Materials, Lewis C., last edition.
4. Toxicologie Industrielle et Intoxications Professionnelles, Lauwerys R.R. last edition.
5. Chemical Hazards of the Workplace, Proctor & Hughes, 4th edition
6. CSST-Québec, Service du Répertoire Toxicologique, 2005

By Edouard Bastarache

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