Working in mines expose workers to many forms of hazard and one of the most dangerous one is caused by dust in mines. They seem to be very small particles but the consequences it brings to a human body when inhaled over time leads to damage highly and if in higher concentration sometime may result to death in mere seconds depending upon the gas.
As all the major operations in the mining field produce dust which when diluted in the air becomes a serious hazard to the health of the workers.
Studying about how dangerous these dust may become when air-borne one should know there are many types of dust occurring in the mines which are equally effective to workers respirable system and some of them leads to disastrous explosions.
The problem of dust has been there since the early days of mining, but with time the advancement of mining techniques started with the introduction of various mechanization in mines, and which has now become a greater difficulty than ever, since machine operations usually give up much more dust than handheld operations make.
When this dust is inhaled by the workers in bigger quantities lead to the development of respiratory diseases such as chronic bronchitis and pneumoconiosis.
Pneumoconiosis is a common term used for occupational lung disease due to dust. When this dust enters the lung different form of tissue reactions has been witnessed. Resulting in different types of diseases such as in specific names are silicosis, asbestosis, siderosis, anthracosis etc caused by specific dust such as of silica, asbestos, iron oxides, talc etc.
Dust in mines and other dusty places of work in factories causes diseases of the lungs which are grouped under the general term pneumoconiosis. The term is applied to all the conditions the lungs resulting from the inhalation of dust over long periods, but in recent years, distinct terms are being used to denote the diseases caused by specified dust as already dictated above. Dust from limestone, shale and some metallic ores are not harmful.
Although it is generally agreed that anthracite and bituminous dust do not produce lung disease, they do cause asthmatic conditions when breathed over a long period. The lung diseases caused by dust may exist for significant periods without producing symptoms or physical inefficiency.
Pneumoconiosis can be classified according to the physical nature of the dust or by the type of tissue response to the particular agent.
The inorganic dust producing the disease is classified as :
- Fibrosis producing- Silicosis and asbestosis are the most vital in this group. These dust are slightly soluble.
- Non-fibrosis producing- Anthracosis is the head example in this group. These dust are inert and is trapped in the tissues but do not produce fibrous tissue.
- Toxic – This group comprises lime, lead, mercury and other heavy metals. These are corrosive and cause several local reactions. If absorbed insufficient amount in the body results in toxic appearance.
This is the most disabling and worst of all the dust diseases. It results in fibrous tissues of the lungs and may ultimately lead to tuberculosis.
Workers engaged on stone drifting, tunnelling, rock drilling, stone crushing on the surface or underground are most prone to silicosis, so also are the workers engaged in grinding and polishing industry and in iron and steel industries.
It has been found that particles of silica measuring 0.5 to 2.5 microns in dia. Are most responsible to produce damage. Dust particles of silica are partly transformed in the alveoli into poisonous silicic acid (H2SiO3) which passes into the blood.
Asbestosis is a kind of pneumoconiosis which results from the inhalation of hydrated magnesium silicate. An important feature of this disease is the presence of asbestos bodies in the lung and sputum.
Fibrosis of the lungs develops faster in asbestosis that in silicosis and extreme cases a person may die of asbestosis within five years of the beginning of symptoms.
Siderosis is caused by inhalation of iron dust. These dust containing silica are the reason for the pathologic changes. Electric arc welders are also the victim of this type of disease due to the presence of ferrous material which is 99% pure in the electrodes used.
The fumes arising from the welding contain inorganic substances mainly finely divided iron oxide. This disease though is not that disabling due to absence of fibrosis but the alveolar walls indicate their pigmentation and resultant thickening.
This disease is familiar to coal miners and also to city dwellers which are exposed to a dusty atmosphere containing a heavy amount of smoke.
Anthracosis simply means black lungs. The particles which are inhaled by the person when enters in the lungs produce a phagocytic reaction similar to that in silicosis. However, the particles inhaled are mostly carbon which is known to be chemically inert and do not harm injury to the lung tissue.
Some particle might travel to some other organs like liver, spleen bone. The affected organs become dark in colour with going time but show no local reactions unless the silica particle is also present.
Symptoms of lung diseases by dust in mines
- Phase 1: The person may look healthy but might having shortness in breath on a very little hard work and has a dry cough.
- Phase 2: Confirmed shortness of breath, chest pain, slow movement and reduced capacity for work.
- Phase 3: Obvious shortness of breath, numerous dry coughing, several times of dry spitting, pulse rate to be generally in an increased state, finally very low rate of work capacity.
These symptoms are favourable to the person which is diseased by Silicosis and can be detected by radiographs of the lung.
Prevention against lung diseases by dust in mines
- Coal dust barriers should be used at regular intervals close to the working where dust formation operation is ongoing.
- Dust traps should be used.
- Water sprinkler should be used to reduce the concentration of dust in the air.
- Examining the dust concentration at working places by suitable instrument and taking effective measures.