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Farmer’s Lung

• Due to inhalation of moldy hay or grain dust (hypersensitivity pneumonitis)
• Grain dust or hay with a moisture content of >30%,
– bacteria and fungi grow rapidly in the dust
– causing rise of temperature of 40 – 50⁰C
• This heat promotes growth of:
– Thermophilic actinomycetes esp. Micropolyspora faeni which causes Farmer’s lung
• Acute Illness
– General and respiratory symptoms and physical signs
• Repeated attacks of acute illness cause
– pulmonary fibrosis and inevitable pulmonary damage and
– Finally Corpulmonale


• Asbestos consists of certain types of fibrous material made up of silicates
• Silica may be combined with:
– Magnesium
– Iron
– Calcium
– Aluminum
• Asbestos is of two types:
1. Serpentine or Chrysolite –
– Hydrated magnesium
– 90% of world’s asbestos production
2. Amphibole
– Contains little magnesium
– Fibers are straight and longer than chrysotile fibers
• Asbestos is used in the manufacture of:
– Asbestos cement
– Fire proof textiles
– Roof tiling
– Brake lining


• Occupational lung disease caused by inhalation of bagasse or sugarcane dust
• First reported in India in a cardboard manufacturing firm near Kolkata
• India has a large sugarcane industry
• Sugarcane fiber is utilized in manufacturing of paper, cardboard and rayon
• Bagassosis occurs due to a thermophilic actinomycete k/a Thermoactinomyces sacchari
• Symptoms:
– Breathlessness
– Cough
– Hemoptysis and
– Slight fever
• Acute diffuse bronchiolitis
• Skiagram:
– Mottling in lungs or shadow


• Due to inhalation of cotton fiber dust over long periods of time
• Symptoms are:
– Chronic cough
– Progressive dyspnea
– Ending in chronic bronchitis and
– Emphysema
• Incidence 7 – 8% in surveys done in Mumbai, Ahmedabad and Delhi

• Park’s Textbook of Preventive and Social Medicine

Types of Pneumoconiosis:


Carbon dust (coal mine dust):
Coal miner’s pneumoconiosis
• Two phases in coal miners pneumoconiosis
1. Simple pneumoconiosis: little ventilatory impairment
– Around 12 yr. of exposure needed for this phase to appear
2. Progressive massive fibrosis (PMF): severe respiratory disability and frequently results in premature death
– Once a background of simple pneumoconiosis has been reached, a PMF may develop out of it even if the exposure is ceased


• Cause of permanent disability and mortality
• Caused by inhalation of dust containing free silica or silicon dioxide (SiO2)
• First reported in India in 1947 from Kolar Gold Mines (Mysore)
• Silica exposure occurs in industries like:
– Mining of:
• Coal
• Mica
• Gold and Silver
• Lead, Zinc, Manganese etc.
– Pottery and ceramic
– Sand blasting
– Metal grinding
– Building and construction
– Rock mining
– Iron and steel etc.


Definition (ILO):
“Pneumoconiosis is the accumulation of dust in the lungs and the tissue reaction to its presence”
• ‘Pneumoconioses’ is the plural
• Dust within the size range of 0.5 to 3 micron pose maximum risk as these can easily enter the alveoli.
– Particles larger than 3 microns don’t reach the alveoli
– Particles smaller than 0.5 microns are exhaled out
– The dust particles which get deposited in the alveoli, cause inflammation in the lungs that can eventually lead to fibrosis of the lung tissue

National Iron+ Initiative

• This initiative is to bring together existing programmes for IFA supplementation for:
– pregnant and lactating women and;
– children in the age group of 6–60 months) and
– Introduce new age groups.
• Thus National Iron+ Initiative will reach the following age groups for supplementation or preventive programming:
– Bi-weekly iron supplementation for preschool children 6 months to 5 years
– Weekly supplementation for children from 1st to 5th grade in Govt. & Govt. Aided schools

National Vitamin A Prophylaxis Programme

• The National Prophylaxis Programme against Nutritional Blindness due to vitamin A deficiency (NPPNB due to VAD) was started in 1970
– with the specific aim of preventing nutritional blindness due to keratomalacia
– As an urgent measure to combat the unacceptably high magnitude of xerophthalmic blindness in the country seen in the 1950s and 1960s
• The Programme was started as a 100 per cent centrally sponsored programme


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