ICMR BULLETIN VOL. 29-No.-9-SEPTEMBER-1999
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ISSN 0377-4910
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BULLETIN
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Vol. 29, No. 9
September, 1999
SILICOSIS - AN UNCOMMONLY DIAGNOSED COMMON
OCCUPATIONAL DISEASE
Pneumoconiosis resulting From exposure io free silica
predisposes to tuberculosis, which is still a major public
may be the commonest and most extensively studied oc
cupational disease of the lung1 and even today, it contin
health problem in developing countries including India’.
Recently crystalline silica has been classified as a human
ues to be among the most serious occupational diseases.
The problem of silicosis is confined not only to the devel
carcinogen (group I) by International Agency for Research
on Cancer (IARC)4.
oping nations, but is also not uncommon in industrialized
nations. For example, in 1983 more than 1 million U.S.
workers were at risk of developing silicosis and 58,000
would eventually develop it:.
Occupational Exposure to Silica
Since the earth’s crust contains about 12% free silica
mostly in the form of quartz, mining and tunneling are
Importance of Silica and Silicosis
The distribution of silicon in nature is«similar to the
the occupations most closely related to the hazard of
silica exposure. The sand stone industry, stone quarrying
and dressing, granite industry, grinding of metals, sand
distribution of carbon in organic matters. Silicon contrib
blasting, iron and steel foundries, silica milling, flint crushing
utes to about 28% of the earth’s crust. Silicon being very
and manufacture of abrasive soaps are some of the occu
reactive does not remain in the element form but com
bines cither with oxygen alone and forms free silica (SiO,)
pations related to silica exposure. Some of the occupa
tions such as slate pencil industry and agate grinding industry
or with oxygen and other elements and forms silicates, eg
which carry high risk of silicosis are peculiar to India.
asbestos. Silica and silicates constitute the bulk of most
There are about 3 million workers at high potential risk of
kinds of rocks, clays and sands. The term silicosis is re
silica exposure. They are employed in various occupa
served for the lung disorder caused by inhalation of free
tions such as mining and quarries (17 lakhs); manu
silica, which is an untreatable progressive disease and
facture of non-metallic products/e., refractory products,
is the commonest and most widespread of all occupational
structural clay, glass, mica. e/c. (6.3 lakhs) and manufac
diseases. Exposure to large amount of free silica can pass
ture of basic metals and alloys, ie. iron and steel, cop
per, ferroalloys?aluminium. etc.(6.1 lakhs)5. In addition
unnoticed because, silica is odourless, non-irritant and does
not cause any immediate noticeable effect and hence is
confused with ordinary dust. Chronic exposure to silica
many of the 54 lakhs construction workers are also at risk
of silica exposure.
Division of Publication & Information, ICMR, New Delhi -110029
Pathogenesis
Silica is one of the most fibrogenic material found
in nature. The reason for its fibroecnicilv has lareelv
remained a matter of speculation. The early workers
attributed its injurious effects to the hard and sharp
edges. Ho wever Gardner6 demonstrated that particles
of silicon carbide which have as sharp and hard edges
as silica do not produce fibrosis in experimental ani
mals and Gye and Purdey' produced inflammation
and necrosis with colloidal silicic acid. Of the theo
ries so far advanced, the fibrogenic factor theory of
of the Kolar gold fields. These findings were later
confirmed by others21
There are very few epidemiological studies on sili
cosis in India and all of them are cross sectional in na
ture. The results of these studies have been summarised
in the table which shows a prevalence of silicosis from
3.5% in ordnance factory to 54.6% in slate pencil indus
try. The prevalence observed in different industries is a
function of the silica concentration in the work environ
ment. duration of w ork and the job demands. Since these
estimates are based on cross sectional studies, they rep
resent the surviving population only. In jobs having high
ing to this theory the macrophages after ingestion
physical demands such as mining, individuals suffering
from silicosis^ilico-tuberculosis may be missed due to
of quartz particles release a factor called macrophage
sickness at the lime of survey and therefore the estimates
Heppleston and styles8 is the most popular. Accord
fibrogenic factor (MFI’), which stimulates fibroblasts
to increase the production of collagen. The existence
of MFF was confirmed by later investigators9
The
would not reflect the actual morbidity.
Table I. Industrv-wise prevalence of silicosis in India
Industry
Prevalence (%)
Reference
Gold mines
8.84
Caplan and Burden-’
causes the translation of collagen from the rough en
Gold mines
13.9
Gowda ■’
doplasmic reticulum, through the secretory vesicles
34.U
to the extracellular fibrillary stale in the fibroblasts
Mica mines & mica
processing industries.
Bihar
Chief Advisory of
factories (CAI-)’1
of the pulmonary interstilium1'. I lowever. this theory
Manganese mines
4.1
Minisin of Labour4
does not take into account the immunologic factor in
Lead and zinc mines
30.4
CAP*
causation of silicosis and does not explain the high
Slone cullers
2o.li
Saini et alz,‘
levels of anti-nuclear factors” *16 and various antibodies
Slone cullers
25.0
Sethi and Kapoor •’
observed in silicotics1" ,s.
Stone cutters
??.2
Gupta ct al:*
foundries
^7
Samal ct al-'
nism of the action of silica dust on the lungs is still not
known, but available evidence indicates that the silica
Ordnance factory
3.5
Viswanathan et al"
Agate workers
38.0
Sadhu ct aln
particles in some manner cause increased permeabil
ity of the digestive vacuole of alveolar macrophages
Glass bangle workers
MFF is a peptide, released from the lysosomes of the
macrophages that have engulfed silica particles. It
In summary, it may be said that the exact mecha
leading to their autodigestion. The dying macrophages
liberate a fibroblast stimulating factor, which causes
increased formation of collagen tissue. Autoimmunity
is probabK responsible in the evolution of the later stages
of silicosis.
Magnitude of the Silicosis Problem in India
Though
mining and metallurgy
in
India were
practiced much earlier than that in Europe. the first cases
of silicosis in this country were described only in the
1940s in gold miners of Kolar by Caplan and Burden .
The silicosis observed among Kolar gold miners w as more
conspicuous by its benign nature in sharp contrast to the
disease in gold miners of South Africa and Australia2 .
Fi brogen icily, the most important biological characteristic
of free silica dust, was found lacking in the siliceous dust
Srhastava et al'
Slate pencil worker*
54.6
Saiycd et al*
Mica mines
processing
5.2
Gangopadhyay ct
aP*
Quartz crushing
12.0
NI()I1“
Stone quarry
22.0
Sand grinding
27.8
xioir
XIOIP
Ceramic* Ct polleric*
15.1
Sahcd ct a. '
mica
The surveys have shown further that the problem of
silicosis is much more severe in the unorganized sector
of industries like slate pencil cutting, stone cutting, agate
industry. civ. Most industries belonging to the unorganized
sector do not fall under the purview of the statutory tools
such as the Factories Act aimed to protect the health and
safety of the working population. Moreover, the
entrepreneurs lack the financial resourcesand technical
96
know-how necessary for the safely of workers. The workers
undiagnosed during life is evidenced by the fact that a
on the other hand arc also not organized and lack the
power of collective bargaining against exploitation.
high prevalence of tuberculosis is observed in post mortem
studies of industrial population occupationally exposed
to high levels of silica. Gardner’0 found evidence of
Considering the huge population employed in mines
and surface industries w ho are al risk of sil ica exposure.
it can be presumed on the basis of available studies that
several hundred thousand workers in India suffer from
silicosis.
tuberculosis in 65-75% silicoiics from various industries.
Yuang Ching Co4”. Barras41 and Schy mczy kicz et al*z found
post mortem evidence of tuberculosis in 48. 50 and 52%
silicoiics respectively. James4’ and Rivers et alu found
evidence of tuberculosis in 40 and 35% cases of PMF
respectively al autopsy examination. How ever, during life.
Clinical Features
Il is important to emphasize that there may be no
the recovery rale of tubercle bacilli from sputum of lhe
South Wales miners with PMF was very low. ie 1.1 %45
symptoms even when the radiographic appearances sug
and 2.7%’”.
gest fairly advanced silicosis. Dyspnoea on exertion is
considered to be the most frequent and directly related
Differential Diagnosis between Silicosis and Tuberculosis
symptom of silicosis. The severity of dyspnoea increases
w ith progress of the disease. In the absence of compli
cating disease (eg tuberculosis), it is rarely complained
of al rest. Slight unproductive cough is a symptom at the
initial stages, later on the quantity of sputum increases.
The symptom complex may resemble chronic bronchi
tis. Excessive sputum production is due to bronchial catarrh
brought about by chronic dust exposure and some times
it is due to secondary bacterial infection of lhe devital
ized lungs. Chest pain and haemoptysis indicate the
possibility of complication like tuberculosis.
Chest Radiography
For the diagnosis of silicosis, history of occupational
exposure to silica is most important. Occurrence of sili
cosis in lhe absence of occupational exposure is rare47.
Radiologically. silicosis and miliary tuberculosis closely
resemble each other, however, miliary* tuberculosis in adults
is rare and the patient is toxaemic. The nodules in miliary
tuberculosis w hether small or large, are less than those in
silicosis. The radiographs of patients w ith silicosis usu
ally show increased translucency as against general loss
of translucency in tuberculosis. In general, the severity of
sy mptoms in a patient wih simple nodular silicosis is much
less as compared to patients of miliary tuberculosis. The
distinction between adult type (post-primary) tuberculo
Chest radiography is the most important tool for the
sis and conglomerate (PMF) radiological shadows is some
diagnosis of silicosis. There appears to be a clear relationship
betw een total dust exposure and the severity of radiographic
times very difficult. However, the conglomerate shadows
of silicosis do not show' cavitation. Associated complica
changes. In the initial stage, there is reticulation of the
tions like pleural effusion and distortion of lhe intra-lho-
lung Helds due to thickening of the perivascular and inter
racic organs due to fibrosis are usually not observed in
communicating lymphatics. The radiographic diagnosis
conglomerate shadow s.
of silicosis can be made with some degree of certainty
only after the appearance of nodules. The silicotic nodules
The above description is that of classical silicosis.
are 2-5 mm in diameter, homogenous in density and usually
However, in some cases, silicosis may* develop w ithin a
bilaterally sy mmetrical.On continued dust exposure, the
few months to 2 years of massive silica exposure. Dra
nodules increase in size and number and eventually cover
matic dy spnoea, w eakness, and w eight loss are often pre
most parts of lhe lungs. Sometimes the silicotic nodules
senting symptoms. The radiographic findings of diffuse
unite and form conglomerate shadows. These conglomerate
alveolar filling differ from those in the more chronic forms
shadows are sometimes described as progressive massive
of silicosis. Histologic findings similar to pulmonary al
fibrosis (PMF). indicating the future course of disease.
veolar proteinosis have been described, and extrapulmonary
(renal and hepatic) abnormalities arc occasionally reported.
Sputum Examination for Tubercle Bacilli
Rapid progression to severe hypoxaemic ventilatory fail?
tire is lhe usual course.
The recovery’of tubercle bacilli in the sputum of patients
suffering from silieo-tubcrculosis is difficult. This is because
of walling in of the tubercle foci by silicotic fibrosis which
Therapy and Management of Complications of Silicosis
prevents the discharge of tubercle bacilli in the sputum.
There is no specific treatment for silicosis, therapy
That a large number of cases of tuberculosis remain
being directed largely at lhe complications of the disease.
Historically, the inhalation of aerosolized aluminium has
been unsuccessful as a specific therapy for silicosis48.
The polymers such as polyvinyl pyridine-N-oxide, and
polybetaine which can prevent experimental silicosis, have
not been found suitable for human disease49-50. Recent
laboratory work, particularly in China, with tetrandrine
has shown in vivo reduction in fibrosis and collagen
synthesis in silica exposed animals treated with this drug.
However, strong evidence of human efficacy is currently
lacking, and there are concerns about the potential toxicity
including the mutagenicity of this drug. Because of the
high prevalence of disease in some countries like China.
India and many other developing nations, investigations
of combinations of drugs and other interventions continue.
Currently, no successful approach has emerged, and the
search for a specific therapy for silicosis has been
unrewarding51.
respiratory diseases. Spirometry may help in appraisal
of the functional loss. The results of the sample surveys
will help in identifying the thrust areas. The thrust areas
may be defined on the basis of the number of people at
risk and the severity of the hazard. Industries having
moderate risk but employing a large work force eg the
mines, or highly hazardous industries employing a smaller
number of workers eg slate pencil industry, agate industry,
quartz grinding industry, etc., fall in this category. For
the reasons already mentioned, there is a special need
for looking into the problems of small scale and cottage
industries.
Implementation of actual control measures
The process of the control of silicosis consists of dust
control measures; and medical measures.
Dust control measures
Prevention and Control of Silicosis and Silicotuberculosis
In the absence of specific therapy for silicosis, there
is a need for planning a national strategy for the preven
tion and control of silicosis and silico-tuberculosis.
Country-wide silico-tuberculosis control should consist
of two major components: (i) definition of the magni
tude of the problem at the national level; and (ii) imple
mentation of actual control measures.
Definition of magnitude ofthe problem at national level
To plan and execute the national strategy for the
prevention of silico-tuberculosis information on the total
population at risk and the number of people already affected
is very essential. The population at risk of silicosis can
be roughly estimated on the basis of available information
on industries, their location, raw material and industrial
processes and employment in each of them. This should
be followed by comprehensive industrial hygiene and
epidemiological surveys in a sample population. After
estimation of the population at risk and identification of
the more vulnerable groups, the industrial and medical
surveys should be carried out. The industrial hygiene
survey should include measurement of the total and
respirable dust at work places and the qualitative analysis
of dust samples. The tools of an epidemiological survey
are recording of the occupational history, clinical history
and physical examination, chest radiograph, sputum
examination and spirometry. Chest radiography is the
most important single investigation having a high degree
of specificity but relatively low sensitivity. The history
and physical examination help in excluding other
There is no silicosis without dust exposure, and the
dust levels in the work environment correlate well with
the incidence as well as the severity of the disease. There
fore, elimination or suppression of dust in the work en
vironment is the key in the control of silicosis. Each in
dustry has its unique work process and therefore it is not
possible to have a single prescription appropriate to all.
The general principles of dust control measures include
substitution of more hazardous substances with innocu
ous substances, isolation and enclosure of the sources of
dust, use of wet methods wherever possible, application
of local and general exhaust, humidification of the work
environment, etc.
Frequently, the management is found to share the
misconception of laymen that the use of dust mask is
sufficient for the prevention of dust related occupational
diseases in the industry. The personal protective equip
ments such as masks should be prescribed only when all
available dust control measures have failed. In fact, the
dust masks are of little value when the dust concentra
tions are high as the dust particles will clog the pores in
the filter resulting in a choking sensation and discon
tinuance of the use of masks by workers. Moreover, the
masks are not suited for hot and humid climate.
Medical surveillance
As per the recommendation of WHO52, the periodi
cal medical examination of workers and the dust mea
surements should be integrated and pursued together so
that the benefits of the dust control measures could be
evaluated in terms of change in morbidity. The medical
98
examination is also necessary' because there exists a small
7.
Gye, W.E.. and Purdcy, WJ. The effects of parenteral ad
ministration of large doses of colloidal silica. BrJ Exp Pathol
3: 75, 1922.
8.
Heppleston. A.G. and Styles. J.A. Activity of a macrophage
susceptible population which is hypersusceptible or oth
erwise unusually responsive to the toxicants because of
genetic factors, age and personal habits53. The medical
factor in collagen formation by silica. Nature 214: 521,1967.
measures for the control of silicosis and silico-tubercu-
losis include pre-employment and periodical examina
tions. incorporating chest x-ray. sputum examination for
tubercle bacilli and spirometry. The pre-employment
medical examination will provide the base-line data for
each individual. The periodical medical examinations shall
aim at early detection of cases of silicosis and tubercu
losis. The success ofthe prevention programme will largely
depend upon the active cooperation of the workers at
risk. Therefore, the need for health education of the workers
9.
by silica-trcated alveolar macrophages. Environ Res 6: 389,
1973.
10.
Nourse. L.D.. Nourse. P.N.. Botes H. and Schwartz. H.M.
The effects of macrophages isolated from the lungs of guinea
pigs dusted with silica on collagen biosynthesis by guinea
pig fibroblasts in cell culture. Environ Res 9: 115. 1975.
II.
Aalto, M. and Kulonen. E. Fractionation of connective
tissue activating factor from soluble medium of silica treated
macrophages. Act Oath Microbiol Scand 87: 241, 1979.
12.
Aho. S.. Peltonen. J.. Jalkanen. M. and Kulonen, E. Effect
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13.
Heppleston A.G. Pathogenesis of mineral pneumoconioses.
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Jones, R.N.. Turner-Warwick. M., Ziskind, M. and Weill. H.
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15.
Turner-Warwick. M., Cole. P.. Weill, H., Jones, R.N. and
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cannot be over emphasized.
Silicosis is an age old occupational disease and re
mains a major occupational health problem in India. It is
responsible for high morbidity and mortality in indus
trial workers. Since there is no specific therapy for this
progressive and irreversible disease, all steps should be
taken for its prevention. The benefits of prevention in
clude the economic benefits such as increased produc
tion by healthy workers, reduction of sickness absentee
ism and less expenditure on health care and above all
the alleviation of human suffering! This common occu
pational disease deserves greater consideration by the
physicians.
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100
ABSTRACTS
Some Research Projects Completed Recently
Expression of epidermal growth factor receptor,
cathepsin I) and p53 oncoprotein as prognostic indicators
in human breast carcinoma.
The study was carried out on biopsy material Irom 50
patients of infiltrating ductal carcinoma obtained in the form
of para Ilin blocks from 2 hospitals. Morphological grading
was done and epidermal growth factor receptor (EGFR).
cathepsin D and p53 oncoprotein expressions were studied
immunohistocheinically. Efforts were also made to corre
late the markers and the morphological classification of breast
carcinomas and to determine their use as prognostic indica
tors.
Of the 50 tumours. 22 (44%) could be grouped as grade
I and 14 (28%) each of grades II and III. Eleven (22%) and
25 (50%) tumours were positive for p53 and EGFR respec
tively. whereas all the tumours showed the expression of
cathepsin D. The p53 positivity in grade I. II and III tumours
was 13.6.21.4 and 35.7% respectively, whereas EGFR posi
tivity was 18.18. 64.28 and 85.71% respectively.
The p53 positivity was found to increase with increas
ing histological grade not only with respect to the number of
patients but also to the number of tumour cells expressing
p53. The expression of EGFR also increased w ith higher
histological grades. Of the 11 tumours positive for p53. 7
had lymph node metastases al the time of presentation, whereas
of the 25 EGFR positive tumours. 17 had lymph node in
volvement. The tumours associated with lymph node involve
ment showed intense staining for cathepsin D. These obser
vations indicated that over expression of p53 and EGFR and
intense staining for cathepsin D were associated with ag
gressive clinical behaviour and poor prognosis of tumours.
It is concluded that immunohistochemistry is a useful
technique for the detection and study of the over expression
of p53. cathepsin D and EGFR.
Sudha Venkatesh
Rama Gopalan
Department of Pathologx
Dr. A.I.. Mudaliar Postgraduate
Institute of Basic Medical Sciences
age related macular degeneration (AMD) and presence
of characteristic lesions in the fundus, and in 20 healthy
individuals matched for age and sex to assess the status of
antioxidant enzymes (superoxide dismutase, catalase and
glutathione peroxidase) as w ell as other antioxidant factors
like ascorbic acid, glutathione and lipid peroxidation. Efforts
were also made to evaluate the effect of oral zinc
supplementation on the activity of antioxidant enzymes and
the clinical course of the AMD. Patients with media
opacities due to any cause precluding proper fundus
examination, presence of any other ocular disease causing
poor vision or distorting the anatomy of the macula and
patients with malignancies, diabetes mellitus. renal and
chronic liver diseases were excluded from the study.
The levels of catalase.‘glutathione peroxidase.
superoxide dismutase and glutathione and lipid peroxidation
were significantly lower in the AMD patients at base-line
w ith no difference in the levels of ascorbic acid, haemoglobin
and zinc. The AMD patients were divided into 2 groups:
group A included 29 patients who received zinc supplement
(S9.2 mg of elemental zinc given orally) and group B included
22 patients who did not receive any zinc therapy. Patients
were followed up at 3 monthly intervals. At base-line, serum
Zn levels were 96.73± 18.62 and 99.97± 13.3 mg% in groups
A and B respectively. There was a significant rise in the
level of Zn after 3 months of Zn supplementation, with
Zn levels rising to 258± 12.60 in group A vs 103.60± 14.72
in group B.
There w as a rise in the level of glutathione peroxidase
at 3 months to 140.17±42.3S units/g lib in group A com
pared to 92.36x37:22 units/g Hb in group B and this rise
was maintained till 24 months. The levels of superoxide
dismutase did not show any rise till 9 months after which
it rose significantly. The levels of catalase showed a sig
nificant rise after 3 months of Zn administration but there
after there was a gradual decrease. There was no change in
the levels of glutathione. l ib and ascorbic acid in both the
groups. There was no significant improvement in ocular
status or visual improvement in the treatment vs non treated
group.
Chennai.
Role of free radicals and antioxidant status and therapeutic
response of Zn in age related macular degeneration.
A prospective study was carried out in 51 patients (age
>55 yr) with reduction in central visual acuity due to
A mod Gupta
Department of Ophthalmology
Postgraduate Institute of
Medical Education and Research
Chandigarh.
101
ICMR NEWS
The following meetings of various technical groups/
committees of the Council were held :
Microscopy Workshop at Eindhovan (August 30-Sep-
tember 3. 1999).
Meetings of the Scientific Advisory Committees (SACs)
of the ICMR Institutes:
Dr. C.P. Puri. Dy. Director (Sr.Grade), Institute for
Research in Reproduction. Mumbai, participated in the
International Symposium on Progestins and Antiprogestins
SAC of the Institute for
August 27-28. 1999
Research in Reproduction.
in the Next Millennium at Jerusalem (August 31-Sep-
tember 3, 1999).
Mumbai
SAC of the National Institute
August 30-31. 1999
of Cholera and Enteric
Dr. T.C. Gupta. Asstt. Director-General, ICMR Hqs..
New Delhi. Dr. Anil Kumar, Asstt. Director, Central
JALMA Institute for Leprosy. Agra and Dr. R.K. Gupta.
Diseases. Calcutta
Asstt. Director, Institute for Research in Medical Statis
tics. New Delhi, participated in the XV International
Meetings of the Task Forces (TFs)ZProjcct Advisory
Committee (PAC) and other meetings held at New
Delhi:
TF on Handigodu Disease
August 17, 1999
Meeting on Phase I Clinical Trial
August 20, 1999
Scientific Meeting of the International Epidemiological
Association at Florence (August 31 -September 4. 1999).
Dr. Mukesh Kumar. Sr. Research Officer. ICMR Hqs..
New Delhi, participated, as a member of Indian delega
tion. in the sixth meeting of India-Japan Joint Committe
with Paromomycin for
on Science and Technology held at Tokyo (September
Leishmaniasis
5-11, 1999).
TF on Rhinosporidiosis
September I. 1999
PAC on Hepatitis
Septembers. 1999
TF on Control of Cancers
September 15. 1999
through Multiorgan Approach
Participation of ICMR Scientists in Scientific Events:
Dr. S.K. Subbarao. Director. Malaria Research Cen
tre. Delhi, participated in the VI meeting of the Com
mittee on Molecular Entomology of the WHO Strategic
Research Steering Committee at Ouagadougou, Burkino
Faso (September 6-8, 1999).
Dr. P.K. Nag. Dy. Director. National Institute of
Occupational Health. Ahmedabad, participated in the XIV
Dr. S.K. Bhattacharya. Director and Dr. G.B. Nair.
International Symposium on Night and Shiftwork:
Dy. Director. National Institute of Cholera and Enteric
Shiftwork in the 21st Century at Wiesensteig (Septem
Diseases, Calcutta, participated in the IX Congress of
ber 13-17. 1999).
Bacteriology & Applied Microbiology and Mycology at
Sydney (August 16-20, 1999).
Dr. T. Shanta Devi. Dy. Director (Sr.Gadc). Tuber
culosis Research Centre. Chennai, participated in the XXX
Dr. S.C. Sehgal. Director. Regional Medical Research
International Union Against Tuberculosis and Lung
Centre. Port Blair, participated in the II meeting of the
Diseases (1UATLS) World Conference on Lung Health
International Leptospirosis Society at Victoria. Austra
at Madrid (September 14-18. 1999).
lia (August 22-25. 1999).
Dr. Kamala Krishnaswamy. Director and Dr.
Hindi Day Celebrations:
Ghafoorunissa. Dy. Director (Sr.Grade). National Insti
tute of Nutrition. Hyderabad, participated in the VIII Asian
Congress of Nutrition at Seoul (August 29-Septcmbcr 2.
1999).
Sh. Atanu Basu. Research Officer. National Institute
of Virology. Pune, participated in the VI Cryoelectron
As part of the Hindi Day celebrations by the ICMR
Headquarters, a popular lecture (in Hindi) on "Health.
Environment and Law" was delivered on September 15.
1999 by Dr. M.C. Gupta. Professor and Head. Depart
ment of Education and Training. National Institute of
Health and Family Welfare. New Delhi.
102
Nutrition
Biomedical Statistics
.1/ the National Institute of Nutrition. Hyderabad:
•
Postgraduate Certificate Course in Nutrition (Decem
ber 1. 1999-February 28.2000).
At the National Institute ofEpidemiology. Chennai:
Laboratory Animal Technology
Training Course in Field Epidemiology (November.
1999). ..
Haematology
At the National Centre for Laboratory Animal Science.
National Institute ofNutrition. Hyderabad:
•
•
Training Course for Laboratory Animal Supervisors
(September I-November 30. 1999).
At the Institute of Immunohaematology. Sfiimbai:
•
Training Course in Advanced Haematology and
I mmuno-hacmatology (October 11-29.’1999).
INDIAN COUNCIL OF MEDICAL RESEARCH
Grant-in-aid for organising Seminars/SymposiaAVorkshops
The Council provides partial financial assistance for organising Seminars Symposia Workshops.
Applications for grant of financial assistance (complete in all respects in the prescribed proforma), "ill be
considered only if furnished at least four months before the date of commencement of the Seminar, Sympo-
sium 'Workshop. etc.
<_______________________________________________________________________________________ '
EDITORIAL BOARD
Chairman
Members
Dr. Padam Singh
Dr. Lal it Kant
Dr. Bela Shah
Dr. N.K. Ganguly
D i rector-G e nera I
Sh. N.C. Saxena
Dr. V. Muthuswamy
Editor
Dr. N. Medappa
Printed and Published by Shri J.N. Mathur for the Indian Council of Medical Research. New Delhi
at the ICMR Offset Press. New Delhi-110 029
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