Occupational Health part 1

MBBS UG class on occupational health in three parts. part 1 includes introduction of occupational health, occupational diseases, ergonomics and Pneumoconiosis

1. Occupational Health-I Dr Mamta G

2. What is Occupational Health? The promotion and maintenance of the highest degree of physical, mental and social well-being of workers in all occupations; the prevention among workers of departures from health caused by their working conditions; the protection of workers in their employment from risks resulting from factors adverse to health; the placing and maintenance of the worker in an occupational environment adapted to his physiological and psychological equipment to summarize, the adaptation of work to man and of each man to his job

3. Ergonomics The term "ergonomics" is derived from the Greek ergon, meaning work and nomos, meaning law. It simply means: "fitting the job to the worker". The object of ergonomics is "to achieve the best mutual adjustment of man and his work, for the improvement of human efficiency and well-being.

4. Ergonomics example- student desks- which is best?? Plus type Zero type Minus type

5. Occupational environment- external/internal 3 types of interaction in a working environment: (a) Man and physical, chemical and biological agents (b) Man and machine (c) Man and man

6. Man and phy /chem/bio agents (1) Physical agents: Heat, cold, humidity, air movement, heat radiation, light, noise, vibrations and ionizing radiation Working and breathing space, toilet, washing and bathing facilities (2) Chemical agents: chemicals, toxic dusts and gases (3) Biological agents: viral, rickettsial , bacterial and parasitic agents which may result from close contact with animals or their products, contaminated water, soil or food.

7. Man and machine Accidents: unguarded machines, protruding and moving parts, poor installation of the plant, lack of safety measures Working for long hours in unphysiological postures is the cause of fatigue, backache, diseases of joints and muscles and impairment of the worker's health and efficiency.

8. Man and man the human relationships amongst workers themselves on the one hand, and those in authority over them on the other. type and rhythm of work, work stability, service conditions, job satisfaction, leadership style, security, workers participation, communication, system of payment, welfare conditions, degree of responsibility, trade union activities, incentives

9. Occupational hazards (a) Physical hazards (b} Chemical hazards (c} Biological hazards (d) Mechanical hazards (e} Psychosocial hazards

10. Physical hazards heat exposure -burns, heat exhaustion, heat stroke and heat cramps; the indirect effects are decreased efficiency, increased fatigue and enhanced accident rates. Radiant heat is the main problem in foundry, glass and steel industries, while heat stagnation is the principal problem in jute and cotton textile industry Eg.Kolar Gold Mines- 65C (20°C to 27°C) is the comfort zone in this country cold exposure-are chilblains, erythrocyanosis , immersion foot, and frostbite, hypothermia

11. Heat

12. Heat stroke

13. Cold

14. Light- poor acute effects of poor illumination are eye strain, headache, eye pain, lachrymation, congestion around the cornea and eye fatigue. The chronic effects on health include " miner's nystagmus “ https://youtu.be/dzlNscl5rWE

15. Light- excess Exposure to excessive brightness or "glare" is associated with discomfort, annoyance and visual fatigue. Intense direct glare may also result in blurring of vision and lead to accidents.

16. Noise Auditory effects which consist of temporary or permanent hearing loss. (ii) Non-auditory effects which consist of nervousness, fatigue, interference with communication by speech, decreased efficiency and annoyance.

17. Vibration From drills and hammers Vibration usually affects the hands and arms. the fine blood vessels of the fingers may become increasingly sensitive to spasm (white fingers}. Exposure to vibration may also produce injuries of the joints of the hands, elbows and shoulders.

18. Vibration S/E- White fingers

19. ULTRAVIOLET RADIATION Occupational exposure to ultraviolet radiation occurs mainly in arc welding. Such radiation mainly affects the eyes, causing intense conjunctivitis and keratitis (welder's flash).

20. Welder’s flash

21. Ionizing radiation In medicine and industry, e.g., X-rays and radio-active isotopes. Important radio-isotopes are cobalt 60 and phosphorus The radiation hazards comprise genetic changes, malformation, cancer, leukaemia, depilation, ulceration, sterility and in extreme cases death Explore effects of - Chernobyl diasater 1986 Fukushima Disaster 2011

22. Chemical Hazards Local- dermatitis, eczema, ulcers and even cancer by primary irritant action Inhalation Dust- mines, foundry, quarry, pottery, textile, wood or stone working industries- cause Pneumoconiosis Gases- simple gases, asphyxiating gases and anaesthetic gases Metals and compounds- lead, antimony, arsenic, beryllium, cadmium, cobalt, manganese, mercury, phosphorus, chromium, zinc Ingestion- lead, mercury, arsenic, zinc·, chromium, cadmium, phosphorus Contact dermatitis by cement

23. Other hazards Biological- The occupational diseases in this category are brucellosis, leptospirosis, anthrax, hydatidosis , psittacosis, tetanus, encephalitis, fungal infections, schistosomiasis and a host of others. Persons working among animal products (e.g. , hair, wool, hides) and agricultural workers Mechanical- machinery, protruding and moving parts Psychosocial- (a ) Psychological and behavioural changes : including hostility, aggressiveness, anxiety, depression, tardiness, alcoholism, drug abuse, sickness, absenteeism (b) Psychosomatic illhealth : including fatigue , headache; pain in the shoulders, neck and back; propensity to peptic ulcer, hypertension, heart disease and rapid aging

24. Break http://nioh.org/ ICMR NIOH - Ahmedabad

25. Occupational diseases- diseases arising out of or during employment

26. Pneumoconiosis

27. Pneumoconiosis Dust within the size range of 0.5 to 3 micron , is a health hazard producing, after a variable period of exposure, a lung disease known as pneumoconiosis, which may gradually cripple a man by reducing his working capacity due to lung fibrosis and other complications.

28. Pneumoconiosis The hazardous effects of dusts on the lungs depend upon a number of factors such as (a) chemical composition (b) fineness (c) concentration of dust in the air (d) period of exposure (e) health status of the person exposed

29. no cure for the pneumoconiosis is known it is essential to prevent these diseases

30. Silicosis Caused by inhalation of dust containing free silica or silicon dioxide First reported in India from the Kolar Gold Mines (Mysore) Seen in mining industry (coal, mica, gold, silver, lead, zinc, manganese and other metals), pottery and ceramic industry , sand blasting, metal grinding, building and construction work, rock mining , iron and steel industry Incubation period -few months to 6 years

31. Clinical features Dense “nodular” fibrosis , the nodules ranging from 3 to 4 mm Early manifestations-irritant cough, dyspnea on exertion and pain in the chest. Advanced disease- impairment of total lung capacity (TLC) X-ray of the chest shows "Snow-storm" Appearance Silicotics are prone to tuberculosis, a condition called Silico-tuberculosis Sputum in silico- tuberculotics rarely shows tubercle bacilli

32. Snow storm appearance on X ray

33. No effective treatment for silicosis Fibrotic changes that have already taken place cannot be reversed. The only way that silicosis can be controlled (if not altogether eliminated) is by (a) rigorous dust control measures, e.g., substitution, complete enclosure, isolation, hydroblasting , good house-keeping, personal protective measures (b) regular physical examination of workers Silicosis is a notifiable disease under the Factories Act 1948 and the Mines Act 1952.

34. of dust

35. Eg. Wet cutting of concrete

36. Personal protection ( never as the only method )

37. Anthracosis= Coal Miner’s pneumoconiosis Two general phases– (1) the first phase is simple pneumoconiosis- little ventilatory impairment. This phase may require about 12 years of work exposure for its development (2) the second phase is characterised by progressive massive fibrosis (PMF) This causes severe respiratory disability and premature death. PMF can develop even without further coal exposure after first phase

38. Anthracosis Risk of death among coal miners is nearly twice that of the general population Coal-miners' pneumoconiosis is a notifiable disease in the Indian Mines Act of 1952, and also compensatable in the Workmen's Compensation (Amendment) Act of 1959

39. Byssinosis Inhalation of cotton fibre dust over long periods of time Symptoms are chronic cough and progressive dyspnoea, ending in chronic bronchitis and emphysema

40. Bagassosis Caused by inhalation of bagasse or sugarcane dust Due to a thermophilic actinomycete - Thermoactinomyces sacchari The sugarcane fibre is used in the manufacturing of paper, cardboard and rayon Symptoms- breathlessness, cough, haemoptysis and slight fever. Initially -acute diffuse bronchiolitis. X ray- mottling in lungs or shadow If left untreated, there is diffuse fibrosis, emphysema and bronchiectasis.

41. Bagasse

42. PREVENTIVE MEASURES DUST CONTROL : use wet process, enclosed apparatus, exhaust ventilation etc., PERSONAL PROTECTION : masks or respirators with mechanical filters or with oxygen or air supply MEDICAL CONTROL : Initial medical examination and periodical medical check-ups of the workers. BAGASSE CONTROL: By keeping the moisture content above 20 per cent and spraying the bagasse with 2 per cent propionic acid, a widely used fungicide

43. Asbestosis Asbestos(silicates) = silica combined with Mg/ Fe/ Ca/ Al/ Na Asbestos is used in the manufacture of asbestos cement, fire-proof textiles, roof tiling, brake lining, gaskets Asbestos enters the body by inhalation, and fine dust deposits in the alveoli. The fibres are insoluble. Serpentine/chrysolite type Amphibole type 90% of asbestos 10% hydrated magnesium silicate contains little magnesium and has diff varieties

44. Asbestosis The dust deposited in the lungs causes - pulmonary fibrosis leading to respiratory insufficiency and death carcinoma of the bronchus mesothelioma of the pleura or peritoneum cancer of the gastro-intestinal tract The disease appear after 5 to 10 years of exposure The fibrosis in asbestosis is due to mechanical irritation, and is peri-bronchial, diffuse in character, and basal in location in contrast to silicosis in which the fibrosis is nodular in character and present in the upper part of the lungs.

45. Asbestosis Characterized by dyspnoea out of proportion to the clinical signs in the lungs. In advanced cases, there may be clubbing of fingers, cardiac distress and cyanosis. The sputum shows " asbestos bodies " which are asbestos fibres coated with fibrin. An X-ray of the chest shows a ground-glass appearance in the lower two-thirds of the lung fields. Once established, the disease is progressive even after removal of the worker from contact

46. Ground Glass Appearance on X Ray

47. Asbestos bodies

48. Asbestosis The preventive measures consists of : (1) use of safer types of asbestos (chrysolite and amosite) (2) substitution of other insulants: glass fibre , mineral wool, calcium silicate, plastic foams, etc. (3) rigorous dust control (4) periodic examination of workers; biological monitoring (clinical, X-ray, lung function) (5) continuing research

49. Farmer’s lung Due to the inhalation of mouldy hay or grain dust In grain dust or hay with a moisture content of over 30 per cent bacteria and fungi grow rapidly, causing a rise of temperature to 40 to 50 deg. C. This heat encourages the growth of thermophilic actinomycetes , of which Micropolyspora faeni is the main cause of farmer's lung . The acute illness is characterized by general and respiratory symptoms and physical signs. Repeated attacks cause pulmonary fibrosis and inevitable pulmonary damage and cor pulmonale.

50. Mouldy Hay and Grain Dust

51. End of Occupational Diseases -I Q1. Identify the pneumoconiosis and the characteristic X ray features shown in image A and B. Q2. Name two occupational diseases caused by Thermophilic actinomycetes. A B