Pneumoconiosis is a lung disease caused by exposure to dust particles between 0.5 to 3 microns, leading to lung fibrosis. Some important dust diseases include silicosis, anthracosis, byssinosis, bagassosis, and asbestosis. Silicosis is caused by silica exposure and has no effective treatment once fibrosis occurs. Prevention relies on dust control measures. Anthracosis affects coal miners and causes lung scarring. Byssinosis is caused by cotton dust. Bagassosis results from sugarcane dust exposure. Asbestosis is caused by asbestos exposure and increases cancer risk. Farmer's lung occurs from moldy hay/grain inhalation.

1. PNEUMOCONIOSIS, ITS EPIDEMIOLOGY,
PREVENTION AND CONTROL.

2. A lung disease due to exposure of lung for
variable period to dust in the size range of
0.5 to 3 microns leading to lung fibrosis
and other complications.

3. Chemical composition
Fineness
Concentration of dust in air
Health status of the person exposed
Period of exposure
HAZARDS OF DUST PARTICALS ON LUNG DEPENDS
ON

4. SILICOSIS
ANTHRACOSIS
BYSSINOSIS
BAGASOSIS
ASBESTOSIS
FARMAR’S LUNG
SOME IMPORTANT DUST DISEASES
ARE:

5. SILICOSIS
Major cause of permanent disability and mortality
First reported in India from Kolar Gold Mines (Mysore) in
1947
The incubation period may vary from a few months to up
to 6 years of exposure.
Silicosis was made a notifiable disease under the
Factories Act 1948 and the Mines Act 1952

6. Particles reach lungs
Ingested by phagocytes
Phagocytes accumulate and block
lymph channels
Dense nodular fibrosis
Respiratory problems
Pathogenesis of silicosis

7. Courtesy of Dr.John Godleski, Brigham and
Women’s Hospital, Boston, Massachusetts.)
Advanced silicosis seen on transection of lung. Scarring
has contracted the upper lobe into a small dark mass (arrow). Note the
dense pleural thickening.

9. Management of silicosis:
There is no effective treatment of silicosis
Fibrotic changes that have already taken place
cannot be reversed.
The only way that silicosis can be controlled is
by
a) Rigorous dust control measures, e.g.,
substitution complete enclosure , isolation ,
hydroblasting etc
b)Regular examination of workers

10. Anthracosis
•Risk of death among coal miners has been nearly
twice that of general population
•It has been declared as a notifiable disease in Indian
Mines Act of 1952 and also compostable in the
Workmen’s Compensation Act of 1959.

11. Premature death
Severe respiratory disability
Progressive massive fibrosis
Little ventilatory impairment
Simple pneumoconiosis
Pathogenesis of anthraconiosis

12. Progressive massive fibrosis in a coal worker. Large
amount of black pigment is associated with fibrosis.
(From Klatt EC: Robbins and Cotran atlas of pathology, ed 2, Elsevier, p. 121.)

13. BYSSINOSIS
•Due to inhalation of cotton fibre dust over long periods
of time
•Symptoms are chronic cough , progressive dyspnoea,
ending in chronic bronchitis and emphysema
•Incidence of byssinosis is reported to be 7 to 8 percent
in three independent surveys carried out in Mumbai,
Ahmedabad and Delhi.

14. Bagassosis
•Due to bagasse or sugarcane
•Reported first by Ganguli and Pal in 1955 in a cardboard
manufacturing firm near Kolkata .
Infection of
Thermoactinomyces sacchari
Breathlessness, cough,
haemoptysis and slight fever
Acute diffuse bronchiolitis
Diffuse fibrosis, emphysema
and bronchiectasis

15. ASBESTOSIS
Asbestos are silicates of varying composition ; the
silica combines with such bases as magnesium, iron,
calcium, sodium and aluminium.
Asbestos are of two types
a) Serpentine or chrysolite variety
b) Amphibole type
Asbestos is mined in Andhra Pradesh, Bihar,
Jharkhand, Karnataka etc

16. Asbestos enter via inhalation
Fine dust deposited via alveoli
Pulmonary fibrosis
Respiratory insufficiency and death,
carcinoma of bronchus , pleura,
peritoneum and gut.

17. Preventive measures
a)Use of safer types of asbestos
b)Substitution of other insulants;
glass fibers, mineral wool, calcium
silicate etc
c)Rigorous dust control
d)Periodic clinical examination

18. Farmer’s lung
Due to inhalation of mouldy hay or grains
Grain dust or hay with moisture
Bacteria and fungus grow
Rise in temperature to 40 to 50
degree Celsius
Infection of Micropolyspora faeni
Pulmonary fibrosis and cor
pulmonale