Community medicine

1. Introduction to Occupational
health and occupational hazards
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2. Occupational Health
• Health Work
(medical fitness for work)
• Work Health
(occupational disease/work related ill health)

3. Aim of Occupational Health
• Promotion & maintenance of highest degree of
physical, mental & social well-being of workers
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4. Ergonomics
Fitting the job to the worker
• To achieve best mutual adjustment of man and his environment
• To reduce industrial accidents and improve overall health and
efficiency of workers
• For prevention of occupational diseases
• For reduction of sickness absenteeism
• To achieve greater efficiency of man and machine
• It Involves
– Right person in right job
– Designing machines, tools, equipment, manufacturing
processes
– Layout of work place 4

5. Occupational Environment
• Man & physical, chemical & biological agents
• Man & machines
• Man & man
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6. Occupational Hazards
HAZARDS
• Physical
• Chemical
• Biological
• Mechanical
• Psychological & Social
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7. Physical hazards
• Heat
– Burn
– Heat exhaustion
– Heat stroke
– Heat cramps
– Heat syncope
– Prickly heat
– Decreased efficiency
– Increased fatigue
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8. • Cold
– Chilblains
– Erythrocyanosis
– Trench-foot
– Frostbite
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9. • Light
– Poor illumination:
• Eye strain
• Headache
• Eye pain
• Lacrimation
• Occupational cataract
• Congestion around cornea
• Eye fatigue
• Miner’s nystagmus
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10. – Excessive brightness:
• Discomfort
• Annoyance
• Visual fatigue
• Blurring of vision
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11. • Pressure
– Caisson disease
– air embolism
– blast (Explosion)
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12. • Noise
– Occupational deafness (Temporary or permanent
hearing loss)
– Nervousness
– Fatigue
– Interference with communication by speech
– Decreased efficiency
– Annoyance
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13. • Vibration
– Drills and hammers user
– Fine blood vessels of the fingers may increasingly
sensitive to spasm (white fingers)
– Injuries of the joints of the hands, elbows and
shoulders
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14. • Ultraviolet radiation
– In arc welding
– Intense conjunctivitis
– Keratitis (welder’s flash): redness of the eyes and
pain
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15. • Ionizing Radiation
– X rays and radio active isotopes in medicines and
industry
– Genetic changes, malformation, cancer, leukemia,
depilation, Aplastic anaemia, pancytopeia,
ulceration, sterility, death
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16. • Electricity
– Burns, death
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17. Chemical hazards
• Local Action
– Dermatitis, eczema, ulcers, cancer
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18. • Inhalation:-
• DUSTS : finely divided solid particles with size ranging
from 0.1 to 150 microns which are released into
atmosphere during crushing, grinding, abrading, loading
and uploading operations.
– Industries that produce dust are mines, foundry, pottery,
textiles, wood, stone etc.
• particles >10micron – settle down from air rapidly
• <10micron – suspended
• <5 micron – inhaled into lungs. This fraction of air is
called “RESPIRABLE DUST” – PNEUMOCOINOSIS.

19. • DUST can be classified as inorganic/organic,
soluble/insoluble
– Inorganic dust:- silica, mica, coal, asbestos etc.
– Organic dust:- cotton, wool, jute, etc.
– Soluble dust:- slowly enters the systemic
circulation and eventually eliminated by body
metabolism.
– Insoluble dust:- gets settled in lungs –
pneumoconiosis
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20. • Inorganic dust
– Coal dust: Anthracosis
– Silica: Silicosis
– Asbestos: Asbestosis, Cancer lung
– Iron: Siderosis
• Organic (Vegetable) dusts
– Cane fibre: Bagassosis
– Cotton dust: Byssinosis
– Tobacco: Tobacossis
– Hay or grain dust: farmer’s lung

21. • GASES : exposure to gases is a common hazard in
industries. They are classified into
– Simple gases : oxygen, hydrogen etc
– Asphyxiating : CO, cyanide gas, SO2 etc
– Anesthetic : chloroform, ether.
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22. • METALS & THEIR COMPOUNDS :
– Their main entry is by inhalation as dust/fumes. They
include lead, antimony, arsenic, beryllium, cadmium, etc.
– Ill effects depends upon :- duration of exposure
dose/conc. of exposure.
– Most of the chemical intoxication respond favorably to
cessation of exposure & medical treatment.

23. • Ingestion:
– not only inhalation, ingestion of chemical substances such
as lead, mercury, arsenic, Zinc, Chromium, phosphorus etc
also produce diseases
– Through contaminated hands, food or cigarettes
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24. BIOLOGICAL HAZARDS
• Persons working among animal products (e.g.: hair,
wool, hides) & agricultural workers are specially
exposed to biological hazards
• Workers may be exposed to infective and parasitic
agents at place of work
• Occupational diseases in this category are:-
Brucellosis, Leptospirosis, Anthrax, Hydatidosis,
Psittacosis, Tetanus, Encephalitis, Fungal infections
etc

25. MECHANICAL HAZARDS
• About 10% of accidents in industry are said to be due
to mechanical causes.
• because of unguarded machinery, moving parts,
protruding parts, poor installation, lack of safety
measure.

26. PSYCHOLOGICAL HAZARDS
• Arise because workers fail to adopt to psychological
social environment.
• Psychological factors: frustration, lack of job
satisfaction, insecurity, poor human relationship,
emotional tensions etc.
• Capacity to adopt is influenced by factors like
:educational, cultural background, family life, social
habits & what the worker expects from employment.

27. • Psychological & behavioral changes :
– hostility, aggressiveness, anxiety, tiredness,
alcoholism, drug abuse, sickness absenteeism.
• Psychosomatic ill health :
– fatigue, headache, pain in the shoulders, neck &
back, propensity to peptic ulcer, Hypertension,
heart disease & rapid aging.

28. Musculo-skeletal problems
• Due to Excessive load on the muscles, ligaments,
tendons and bone.
• Due to Insufficient circulation to the Musculoskeletal
system.
• Work that requires activity of a small group of relatively
weak muscles (such as continuous use of fingers of the
dominant hand in data entry).

29. Common sites for Musculo-skeletal problems
• Neck
• Forearm
• Wrist
• Fingers
• Back
• Knee

30. Thank You
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