Coal worker's pneumoconiosis

1. Coal worker’s Coal worker’s
PneumoconiosisPneumoconiosis
Dr. Gopalrao Jogdand, M.D. Ph.D.Dr. Gopalrao Jogdand, M.D. Ph.D.
Professor & Head,Professor & Head,
Department of Community MedicineDepartment of Community Medicine

2. DefinitionDefinition
A chronic inflammatory disease of the A chronic inflammatory disease of the
lungs caused by inhalation of coal dust. lungs caused by inhalation of coal dust.
This disease is also called as black lung.This disease is also called as black lung.

3. Historical BackgroundHistorical Background
First documented in Scottish coal miners First documented in Scottish coal miners
in 1836.in 1836.
Following world war I condition was Following world war I condition was
detected in coal miners of South Wales.detected in coal miners of South Wales.
In 1942 committee on industrial In 1942 committee on industrial
pulmonary diseases of the medical pulmonary diseases of the medical
research council introduced the term coal research council introduced the term coal
workers pneumoconiosis.workers pneumoconiosis.

4. Prevalence & RisksPrevalence & Risks
Prevalence (1917-1920): 22/1000 Prevalence (1917-1920): 22/1000
miners.miners.
Current Prevalence: Less than 8/1000 Current Prevalence: Less than 8/1000
Miners.Miners.
Risk: 24 years exposure vs 36 yearsRisk: 24 years exposure vs 36 years
Low dust 5% 10%Low dust 5% 10%
High dust 15% 40%High dust 15% 40%

5. What causes CWPWhat causes CWP
The disease is caused by inhalation of The disease is caused by inhalation of
the coal dust.the coal dust.
Inhalation of the respirable dust causes Inhalation of the respirable dust causes
CWP.CWP.
Respirable dust:. coal dust particles of Respirable dust:. coal dust particles of
the size 0.5 to 3 microns.the size 0.5 to 3 microns.

6. Clinical signs & Clinical signs &
symptomssymptoms
First stage is called as simple pneumoconiosis First stage is called as simple pneumoconiosis
which is characterized by chronic cough, fever, which is characterized by chronic cough, fever,
expectoration and dysponea on exertion, this is expectoration and dysponea on exertion, this is
associated with little ventilatory impairment. associated with little ventilatory impairment.
This stage will develop after 10-12 years of This stage will develop after 10-12 years of
exposure.exposure.
Second stage is called progressive massive Second stage is called progressive massive
fibrosis. It is irreversible and continues even fibrosis. It is irreversible and continues even
after cessation of the exposure, prognosis is after cessation of the exposure, prognosis is
not good. not good.

7. Pathological ChangesPathological Changes
Macroscopic appearanceMacroscopic appearance
simple pneumoconiosis: Hard grey/black simple pneumoconiosis: Hard grey/black
nodules found in the upper lobes and nodules found in the upper lobes and
perihilar region. perihilar region.
Progressive Massive fibrosis: Large firm Progressive Massive fibrosis: Large firm
masses, shrunken upper lobes, masses, shrunken upper lobes,
emphysematous lower lobes and sub emphysematous lower lobes and sub
pleural blebs.pleural blebs.

8. Continued….Continued….
Microscopic appearance:Microscopic appearance:
Central zone: hyaline connective tissue Central zone: hyaline connective tissue
in concentric layers, acellular, capillaries in concentric layers, acellular, capillaries
not present.not present.
Middle zone: cellular connective tissue Middle zone: cellular connective tissue
found.found.
Peripheral zone: halo of macrophages Peripheral zone: halo of macrophages
projecting in lung parenchyma, high coal projecting in lung parenchyma, high coal
content.content.

9. DiagnosisDiagnosis
History of exposure.History of exposure.
Lung function Test: varies from normal to Lung function Test: varies from normal to
obstructive or restrictive or combination obstructive or restrictive or combination
of both.of both.
Diffusion decreased.Diffusion decreased.
Dysponea on exertion.Dysponea on exertion.
X-ray chest: small nodules, 1-10 mm in X-ray chest: small nodules, 1-10 mm in
upper lung zones, ground glass upper lung zones, ground glass
appearance of the lung.appearance of the lung.

10. Radiograph of CWPRadiograph of CWP

11. Pulmonary function Pulmonary function
teststests
Used to test the ability of the lungs to Used to test the ability of the lungs to
take in air (inspiration). Often used in take in air (inspiration). Often used in
conjunction of the X ray chest.conjunction of the X ray chest.
Forced vital capacity (FVC) and FEV1 Forced vital capacity (FVC) and FEV1
(forced expiratory volume in one second) (forced expiratory volume in one second)
are used to diagnose lung diseaseare used to diagnose lung disease

12. ComplicationsComplications
Respiratory: Pneumothorax, chronic Respiratory: Pneumothorax, chronic
obstructive pulmonary disease, cor obstructive pulmonary disease, cor
pulmonale.pulmonale.
Infectious diseases: Tuberculosis.Infectious diseases: Tuberculosis.
Vascular diseases. Vascular diseases.

13. TreatmentTreatment
Terminate exposure to prevent PMF.Terminate exposure to prevent PMF.
Corticosteroids, pulmonary lavage, lung Corticosteroids, pulmonary lavage, lung
transplant.transplant.
Treat complications: Pneumothorax, Treat complications: Pneumothorax,
COPD, cor pulmonale, T.B., vascular COPD, cor pulmonale, T.B., vascular
diseases.diseases.

14. Prevention and controlPrevention and control
Preplacement and periodic medical Preplacement and periodic medical
examination of workers.examination of workers.
Use of protective equipments by the Use of protective equipments by the
workers.workers.
Use of dust suppression measures.Use of dust suppression measures.
Gravimetric dust sampling in dusty areas.Gravimetric dust sampling in dusty areas.
Exhaust ventilation.Exhaust ventilation.