Section 1 - CHEMICAL PRODUCT AND COMPANY IDENTIFICATION

PRODUCT NAME

WOLLASTONITE

NFPA

PRODUCT USE

Constituent for lime glass, portland cement, reinforcing filler in elastomers and
plastics, absorbent for liquids, gases and vapours, as an anti- caking agent, suspension
agent, pigment and pigment extender, binder for refractory material, in chromatography and
in road construction. As an ingredient for welding fluxes. Low- aspect ratio products
(powder wollastonite or milled grades) with aspect ratios of 3:1 to 5; 1 are used as
general fillers, in ceramics and in metallurgical fluxing. High aspect ratio products with
ratios of 1%:1 to 20:1 are used as functional fillers in the reinforcement of
thermoplastic and thermoset polymer compounds and as a replacement for asbestos.

SYNONYMS

Ca(SiO3), Ca-H2-O3-Si, "calcium silicate", "calcium metasilicate", aedelforsite,
gillebachite, okenite, rivaite, schalstein, "tabular spar", vilnite, Casiflux,
Gillebachite, Cabolite, Okenite, Micro-cell, Rivaite, Silene, Vansil, Tobermorite,
Vilnite, Xonaltite, Xonotlite, "Table Spate", Wollastokup, "Wollastonite G", "Vancil W10",
W20, W30, "Cab-O-Lite 100", "Cab-O-Lite 100", 130, 160, "F1 P4", "Kemolit A60", ASB4,
ASB8, N, "Nyad 10", 325, 400, "1250 1006", 1250T, "Nycor 200", 300, SP10

Section 2 - HAZARDS IDENTIFICATION

CANADIAN WHMIS SYMBOLS

EMERGENCY OVERVIEW

RISK

POTENTIAL HEALTH EFFECTS

ACUTE HEALTH EFFECTS

SWALLOWED

  Although ingestion is not thought to produce harmful effects, the material may still be damaging to the health of the individual following ingestion, especially where pre-  existing organ (e.g. liver, kidney) damage is evident. Present definitions of harmful or toxic substances are generally based on doses producing mortality (death) rather than those producing morbidity (disease, ill-health). Gastrointestinal tract discomfort may produce nausea and vomiting. In an occupational setting however, ingestion of insignificant quantities is not thought to be cause for concern.  Considered an unlikely route of entry in commercial/industrial environments.  Ingestion may result in nausea, abdominal irritation, pain and diarrhea.  

EYE

  Although the material is not thought to be an irritant, direct contact with the eye may produce transient discomfort characterized by tearing or conjunctival redness (as with windburn).  The dust may produce eye discomfort and abrasive eye inflammation.  

SKIN

  The material is not thought to produce adverse health effects or skin irritation following contact (as classified using animal models). Nevertheless, good hygiene practice requires that exposure be kept to a minimum and that suitable gloves be used in an occupational setting.  Irritation and skin reactions are possible with sensitive skin.  

INHALED

  The material is not thought to produce adverse health effects or irritation of the respiratory tract (as classified using animal models). Nevertheless, good hygiene practice requires that exposure be kept to a minimum and that suitable control measures be used in an occupational setting.  Persons with impaired respiratory function, airway diseases and conditions such as emphysema or chronic bronchitis, may incur further disability if excessive concentrations of particulate are inhaled.  

CHRONIC HEALTH EFFECTS

  Primary route of exposure is usually by inhalation of generated dust.  Prolonged or repeated skin contact may cause drying with cracking,irritation and possible dermatitis following.  In a small cohort mortality study of workers in a wollastonite quarry, the  observed number of deaths from all cancers combined and lung cancer were  lower than expected.  In an inhalation study in rats no increase in tumour incidence was  observed but the number of fibres with lengths exceeding 5 um and a  diameter of less than 3 um was relatively low. Four grades of wollastonite  of different fibre size were tested for carcinogenicity in one experiment  in rats by intrapleural implantation. There was no information on the  purity of the four samples used. A slight increase in the incidence of  pleural sarcomas was observed with three grades, all of which contained  fibres greater than 4 um in length and less than 0.5 um in diameter. In  two studies by intraperitoneal injection in rats using wollastonite with  median fibre lengths of 8.1 um and 5.6 um respectively, no intra-abdominal  tumours were found.  Evidence from wollastonite miners suggests that occupational exposure can  cause impaired respiratory function and pneumoconiosis. However animal  studies have demonstrated that wollastonite fibres have low biopersistence  and induce a transient inflammatory response compared to various forms of  asbestos. A two-year inhalation study in rats at one dose showed no  significant inflammation or fibrosis.  Long term exposure to high dust concentrations may cause changes in lung function i.e. pneumoconiosis; caused by particles less than 0.5 micron penetrating and remaining in the lung. Prime symptom is breathlessness; lung shadows show on X-ray.  Repeated exposures, in an occupational setting, to high levels of fine- divided dusts may produce a condition known as pneumoconiosis which is the lodgement of any inhaled dusts in the lung irrespective of the effect. This is particularly true when a significant number of particles less than 0.5 microns (1/50,000 inch), are present. Lung shadows are seen in the X-ray. Symptoms of pneumoconiosis may include a progressive dry cough, shortness of breath on exertion, increased chest expansion, weakness and weight loss. As the disease progresses the cough produces a stringy mucous, vital capacity decreases further and shortness of breath becomes more severe. Pneumoconiosis is the accumulation of dusts in the lungs and the tissue reaction in its presence. It is further classified as being of noncollagenous or collagenous types. Noncollagenous pneumoconiosis, the benign form, is identified by minimal stromal reaction, consists mainly of reticulin fibres, an intact alveolar architecture and is potentially reversible.