Document wrOKJ6awQXwkjVEgpK20k2Qv6
FILE NAME Talc TALC
DATE 1959
DOC TALC007
DOCUMENT DESCRIPTION Excerpt from the Annual Report of the Chief Inspector of Factories on Industrial Health
papers
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vonad 4 poorer chance of recovery than one who otherwise had
This well substantiated past experience
owing to the availability of
may however not be
effective
healthy
so true
lungs today
tuberculosis particularly in the
early
result of which the incidence of risk of infection by contact has beenturbeedrucucleodsis has fallen markedly and the
Exposure to silica dust occurs in the
containing rock and stone in the
mining and quarrying of silica-
materials among masons manufacture of certain types of refractory
and the pottery industries and coalminers and in the metal founding
where silicosis has occurred mention a few of the industries and occupations
The precise manner in
tissue is still not finally
ewshtiacbhlissihleicda exerts its harmful action on the lung Originally it was considered to be
mechanical irritation caused by the small sharp
recent view is that the effect is
silicic acid as the silica very slowly dissolves in the
immunological iasntdhearefsouultrtohf atnhe most recent that the fibrous tissue formed in the lungs
response
The amorphous synthetic silicas which which have become
in recent years are
increasingly used
composed of extremelyextremely minute particles which remain
small even when aggregated into clumps
clumps
Animal
determine their fibrogenic activity andand
main negative and so far no harmful harmful
general
dusting experiments to toxicity have been in the
use of these
effects in humans are known The
compounds is being kept
organs remote from the lungs is being borne
microscopically Asbestos consists mainly of the silicates of
forms and the dust which
magnesiummagnesium and iron in fibrous
fibres is a cause of fibrosis of
is in the form of long sharp
resemble those of
the lungs The symptoms of asbestosis
silicosis although the ray changes are very different
Like silicosis asbestosis is a disease of insidious
permanent disablement On the other hand
onset which may lead to
associated with tuberculosis than
asbestosis has been less evidently
evidence of
silicosis has been There is moreover
cancer
an association Asbestos
between
asbestosis
but
not
silicosis
and
lung
dust is generally considered to act
irritant to the lung tissues
as a mechanical
With the exception of asbestos silicates silica in
not cause damage to the lung tissue to
a combined form do
by free silica
a degree comparable to that caused
in
However prolonged exposure to some other silicate dusts
heavy concentrations may produce a
being that due to talc dust
pneumoconiosis the best known Talc or soapstone is a silicate occurring in
fibrous or plate form closely resembling asbestos
particles confer
chemically
The flat plate
good lubricating properties for which talc is
in industry particularly in the rubber plastics and metal
widely used
founding industries
54
Although earlier fatal c
had been described the first examination was described Inspector of Factories and | cases have been reported bo
Cases of a diffuse fibros
dust have been reported a men were engaged in the m powder in which process is oxidised to alumina a
of dust of less than 10 mi
period is very variable and are tiredness loss of appet ness of the chest ray .
a diffuse increased fibrosi may be associated with t death often results from F
This condition may hav has occurred in individu bauxite The fumes to
alumina and finely divided
A study of death certif lungs and the occupation
to be found on page 38
Inert Dusts not producing
Certain other dusts chic of barium when inhaled ray appearances of the those produced by silic metallic compounds whi the part of the lung tissu to the individual . Dr. A attention in 1936 to X Clinical examination of
apparently in good healt findings and follow
many years have shown may even regress and d It would seem that th
welding causes no harm described as occurring
iron Sometimes how
involving exposure to b example in foundries |
to a silicotic reaction
Dusts Causing Inflamm The dusts arising fror
vanadium osmium or
seats
7
ent of
|
sags largely as a
_ markedly and the
| quarrying of silica-
types of refractory
| the metal founding
ries and occupations
action on the lung
"considered to be
y the small sharp iew that crystalline resulguhr A more
ut by liberation of
Que and cell fluids
by a concentration
ed silica particles ;
rmed in the lungs
increasingly used
cles which remain
ng experiments to have been in the
are known The ation and clearly
__ These particles be produced in
nd iron in fibrous
n of long sharp
uns of asbestosis
re very different ich may lead to
cen less evidently
re is moreover
cosis and lung s a mechanical
| bined form do to that caused
r silicate dusts e best known
e occurring in
The flat plate
is widely used Eling industries
Although earlier fatal cases of
had been described the first
pneumoconiosis due to talc dust exposure
case in Great Britain to be
examination was described by Dr. A. I. G.
proved by pathological
Inspector of Factories and his
McLaughlin H.M. Medical
authors in 1949. Since then
many additional
cases have been reported both here and abroad
,
men were engaged in the
powder in which
manufacture by stamping and mixing of aluminium
is oxidised to
processes a proportion of the finely divided aluminium
alumina aluminium oxide A
considerable
of dust of less than 10 microns in size
concentration
period is very variable and lasts from
may thus be produced The latent
are tiredness loss of appetite and a few months to many years Symptoms
ness of the chest ray changes loss of weight dyspnoea cough and tighta diffuse increased fibrosis with are not characteristic but the lungs show
may be associated with
bronchitis and emphysema The condition
tuberculosis and
death often results from
spontaneous pneumothorax and
This
pneumonia or sided heart failure
condition may have some relation to the
has
occurred
in
individuals
preparing
fibrosis
corundum
of the lung
which
bauxite The fumes to which such workers arealuminium oxide from
exposed contain both
to be found on page 38 of this Report
Inert Dusts not
producing Fibrosis of the Lungs Certain other dusts chiefly the oxides of iron
of barium when inhaled over
and tin and certain compounds
ray appearances of the
a long period of time produce changes in the
those produced by silica lungs which may be difficult to distinguish from
dust These aggregations of dust
particles of
the remain toto
individualindividual individual individual individual Dr.Dr. A. T. Doig andand
attention in 1936 to
Doig
Dr. A. I. G. I.
McLaughlinMcLaughlinMcLaughlinMcLaughlinMcLaughlin first first calledcalledcalled
ray changes in the lungs of 16 electric
Clinical examination of these men showed
arc welders
apparently in good health Work
no disability and all were
findings
and
follow
by other investigators has borne out these examinations
many years have shown
by Drs Doig and McLaughlin over
that the ray abnormality does not
may even regress and disappear after some
progress but
years It would seem that the inhalation of
absence from exposure
iron oxide dust produced
welding causes no harm
during as
This condition known as siderosis has also been
described occurring in silver polishers who use
however iron Sometimes
welders who have worrkoeudge ionr red oxide of
circumstances
become example example example example example example in foundries foundries foundriesfoundries foundries foundries foundriesfoundries have havehave become becomebecome become
disabled disabled disabled disabled disabled disableddisabled this this thisthis is is due due due in all all all probabilityprobabilityprobability probability probability probability probability probability probability
Dusts Causing Inflammation of the Lungs
The dusts arising from the processing of certain compounds of
manganese
vanadium osmium or beryllium cause acute inflammation of the mucous 55
was,
t
so