Hafnium Oxide Toxicty
By Edouard Bastarache
Identification
:
Synonym: Hafnium Dioxide
Formula: HfO2
CAS # 12055-23-1
Source :
Hafnium (Hf) is found in association
with zirconium ores, production based on zircon (ZrSiO4)
concentrates which contain 0.5% to 2% hafnium. This metal has
outstanding corrosion resistance accounting for some of its major
applications.
Compounds used in
Ceramics :
-Hafnium Boride,
-Hafnium Carbide,
-Hafnium Nitride,
-Hafnium Oxide,
-Hafnium Silicate,
-Hafnium Titanate.
Toxicology of Hafnium
Oxide :
Routes of Entry :
Inhalation, skin, and ingestion.
Effects of Overexposure
:
I-Inhalation :
May cause pulmonary irritation. Coughing
or sneezing may occur.
II-Dermal/Eye Contact :
May cause irritation, inflammation may
occur.
III-Ingestion :
Ingestion may cause some discomfort.
Hafnium is considered relatively non-toxic due to poor absorption
of it in the alimentary tract of mammals.
Chronic Exposure :
It may cause liver damage.
It may also cause a benign
pneumoconiosis by dust accumulation, without fibrosis and
ventilatory effect, and without special predisposition to
tuberculosis and/or lung cancer as encountered in silicosis and
abestosis.
Medical Conditions Generally
Aggravated by Exposure :
Previous respiratory and eye
disorders.
Carcinogenicity :
Hafnium oxide is not considered a
carcinogen by official regulatory bodies.
Quebec's Exposure Limits
:
VEMP : 0.5 mg/m³
References :
1-Occupational Medicine,Carl Zenz,
last edition.
2-Clinical Environmental Health and
Toxic Exposures, Sullivan & Krieger; last edition.
3-Sax'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
Edouard Bastarache M.D.
Occupational & Environmental Medicine
Author of "Substitutions for Raw Ceramic Materials"
Tracy, Québec, CANADA
edouardb@sorel-tracy.qc.ca
http://www.sorel-tracy.qc.ca/~edouardb/
Out Bound Links
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