|
1)
Silicosis
2)
Asbestosis
3)
Byssinosis
4)
Tobacco
5)
Agate
6)
Salt Workers
1)
Silicosis: Silicosis was studied among
following industries:
a) Slate
pencil industries
b)
Agate industries
c) Quartz
grinding industries
d)
Stone quarries.
The
prevalence of silicosis was studied in each industry.
The prevalence was very high and cases of simple silicosis
and progressive massive fibrosis were found.
The mortality was also very high.
The intervention measures to reduce the dust level
and thereby prevention were recommended for each industries.
2)
Asbestosis:
Asbestosis
was studied in:
a)
Asbestos cement industries
b)
Asbestos textile industries
c) Asbestos
mining and milling industries
The
prevalence of asbestosis was higher in asbestos textile and
asbestos mining industries.
3)
Byssinosis:
Byssinosis
was studied in cotton textile mills of Ahmedabad. The prevalence of byssinosis was especially high in blow
room, card room of spinning dept. of
textile mills.
To reduce the incidence of byssinosis recommendation
were given and the report was submitted to the chief inspector
of factories.
Intervention
studies were carried out in ginning industries to suggest
use of bractless cotton for prevention of byssinosis.
4) Occupational Health of Tobacco Harvesters and their Prevention
The
Ministry of Health and Family Welfare, Govt. of India sponsors
this project. There
are many studies on acute health effects due to green tobacco
handling in agricultural workers but no information is available
on long term health effects of green tobacco handling.
Therefore, the main objective of the study is to find
out chronic health effect of exposure to green tobacco during
the cultivation of tobacco. The second objective of the study is to evaluate effectiveness
of various types of gloves and suggest suitable hand gloves
for prevention of absorption of nicotine, which is a toxic
chemical in tobacco plants.
The
study has been undertaken in Kaira district of Gujarat state
where maximum tobacco is grown. 685 exposed workers from three villages and 655 non-exposed
workers from two villages were examined in the study.
To find out the chronic health effect, prevalence of
hypertension, ECG abnormalities, reproductive abnormalities
and visual activity were examined in tobacco workers.
The
result of the study regarding hypertension, ECG and reproductive
abnormalities were compared in exposed and control groups.
The data were comparable in both the groups and did not show
statistical significance.
To
prevent the absorption of nicotine through skin, different
types of hand gloves like cotton, cotton PVC polka dots, cotton
polyester, only polyester and nylone have been tested for
their efficacy and suitability. Before and after the use of
gloves sample have been collected, nicotine and its metabolite,
cotinine from urine samples have been measured by HPLC method.
This work is under progress and results will be reported
within a short time.
5)
. Prevention, Treatment
and Control of Silicosis and Silico-tuberculosis among the
Agate workers of Khmabhat:
This
study is sponsored by the Ministry of Health and Family Welfare,
Government of India, Agate Industry, a cottage type of industry,
which is located in and around Khambhat (Cambay), in Gujarat.
Among other processes agate grinding in which agate
stones are grinded against a rotating emery wheel, generates
lots of silica dust that is most hazardous.
An epidemiological study carried out by NIOH in 1987
showed 38.2% prevalence of silicosis among the agate grinders.It
was also observed that the dust generated by agate grinding
machine also pervaded the indoor air thereby, resulting in
dust exposure to the family members and community subjects
residing in and neighboring houses although, they are not
engaged in this occupation.
The
study was undertaken in Khambhat and surrounding villages.
A total of 1927 subjects which included 397 present
grinders, 341 past grinders, 127 family members, 748 community
persons and 314 subjects working in processes other than grinding
such as polishing, drilling, chipping etc.
In addition 841 subjects who never worked in agate
industry were selected as control from two villages situated
about 20 km from Khambhat.
Detailed
medical examination and chest x-ray were carried out in all
the subjects. Pulmonary
Function Test (PFT) were carried out in 1575 subjects and
serum Angiotensin Convertase Enzyme (ACE) and copper estimation
in 342 subjects were carried out.
The
prevalence of tuberculosis (TB) in control subjects was 3.7%
which is comparable with the national prevalence.
As compared to this, the prevalence of tuberculosis
(TB) in other categories was significantly higher (18.8-53.7%).
The odds ratio of 6.1-6.6% in the categories of community
subjects, other workers and family members was significantly
higher than the controls, whereas, that in present grinders
had odds ratio of 9.6% and in past grinders it was 30.3%.
The prevalence of silicosis was compared in all the
groups (6.8-38.1) as compared to controls (zero prevalence).
Similarly, the prevalence of silico-tuberculosis was
also higher in all the other groups (2.8-27.3) as compared
to controls (zero prevalence).
The prevalence of silicosis also showed significantly
increasing trend with the duration of grinding.
The
prevalence of all the three diseases was significantly higher
in the subjects having suffered from pulmonary tuberculosis
in the past as compared to those who never suffered.
Among the subjects with past history of tuberculosis,
the odds were at least 9.3 times higher for tuberculosis,
5 times higher for silicosis and 6.2 times for silico-tuberculosis
then those without.
The levels of serum Angiotensin Convertase Enzyme (ACE)
and copper showed significant increase with the increasing
grade of profusion in silicosis and silico-tuberculosis.
The
multiple regression analysis with adjusted R2 showed
30% variation in profusion grade is explained by serum Angiotensin
Convertase Enzyme (ACE), copper, age and tuberculosis status.
However, the contribution of serum Angiotensin Convertase
Enzyme (ACE) is highest as suggested by the regression co-efficient.
Hence, serum Angiotensin Convertase Enzyme (ACE) can
be used as a good indicator of progression or profusion of
small opacities in workers exposed to the silica dust.
6) .
Prevention and Control of Occupational Health Hazards
Among Salt Workers Working in Remote Desert Areas of Gujarat
and Western Rajasthan
The
subsoil brine in the desert areas of the Little Rann of Kutch
in Gujarat and Western Rajasthan contains very high salinity
(15-20%) as compared to that of seawater (3.4%).
The workers engaged in the salt production under the
unorganized sector have to stay and work in isolation at the
remote sites in the adverse weather of the desert during the
work season (from October to June).
The workers, most of the time barefoot, enter the brine
for 6-8 hours during the process of crystal reshuffling.
The hazardous effects of intense reflection of sunlight
from the salt and a direct effect of sodium chloride dust
on mucosa of the eye are responsible for various eye morbidities,
whereas the direct contact of feet and hands with highly concentrated
salt solution causes different types of skin problems among
these workers and are widely reported in the literature.
The
National Institute of Occupational Health (NIOH), Ahmedabad,
carried out a study in 143 workers (103 men and 40 women)
from a salt manufacturing site in the Little Rann of Kutch
and a control group of 128 subjects (76 men and 52 women)
from a nearby village.
The skin abnormalities were observed in 51.74% salt
workers as compared to 11.71% controls, whereas the eye abnormalities
were noted in 45.45% of workers and 33.59% of control subjects.
In addition to this, high prevalence of hypertension
was observed in both – the control and exposed groups.
The controls had a prevalence of 13.15% in men and
19.23% in women, whereas in the salt workers it was still
higher – 40.77% and 30.0% for respective sexes.
The exposed group also showed an overall high prevalence
of hypertensive retinopathy (22.3% in men and 17.5% in women)
as compared to controls.
The
causative factor(s) responsible for development of hypertension
and hypertensive retinopathy remain to be identified. The repeated injuries by the sharp edges of salt crystals
cause lesions such as ulcers, fissures, cracks and warts in
the skin. The
resultant breech in the integrity of the skin may help enhanced
absorption of salt into the body of the workers as their hands
and feet remain in prolonged and direct contact with highly
concentrated brine during work hours.
The drinking water used by the exposed and the control
population has a high salt content, which may partly be responsible
for the higher prevalence of hypertension.
However, this hypothesis needs to be confirmed.
To investigate these occupational hazards in depth
and for their prevention, an intervention study sponsored
by the Ministry of Health and Family Welfare, Government of
India, involving 1500 salt workers and 1200 control subjects
is planned.
So
far, 1332 salt workers and 115 control subjects have been
included in the study.
Detailed occupational and medical history with skin
and ophthalmic examinations along with blood pressure measurement
as per the WHO protocol is carried out in these subjects.
Investigations like serum urea, cholesterol, creatinine,
electrolytes and Angiotensine Convertase Enzyme (ACE), blood
haemoglobin, urinalysis and electrocardiography are also carried
out. Study of
the remaining subjects and data analysis are under progress.
|