Occupational Health Prof. Ashry Gad Mohamed Prof. of Epidemiology College of Medicine & KKUH King Saud University

Occupational Health I-Occupational Hygiene Study of adverse environmental factors and stresses arising at work place. Recognition Assessment Engineering control II-Occupational Medicine Science and art concerned with health status of workers engaged in any occupation Diagnosis Treatment

Why we study occupational health? 1-Prevention or reduction of loss of machine. 2-Prevention or reduction of sickness and absenteeism. 3-Reduction of cost of medical treatment. 4-Reduction of compensation claims. 5-Increase well-trained workers. 6-Reduction of labor turn over. 7-Increase morals of workers.

Objectives 1- Prevention of occupational diseases and injuries. 2-Prevention of fatigue and malformation. 3-Maintenance and promotion of health of workers (physically, mentally & socially)

Occupational health team. Engineers & Chemists Substitution Isolation Enclosure Ventilation Physicians & nurses Pre-employment Periodic Rehabilitation Medical examination First aid Health education Nutritional programs Social workers Working hours Transportation Housing Personal or public problems Nutritional programs

Factors affect worker’s health 1-Physical factors: heat, cold, noise, atmospheric pressure, light & radiation. 2-Mechanical factors: friction & vibration. 3-Chemical environment: solids, liquids & gases. 4-Social environment: relation between workers, colleagues & supervisors. 5-Biological environment: micro-organisms. 6-Factors of accidents: causes of accidents. 7-Mode of performance: sclerosis, skin diseases.

Heat Heat production = Metabolism (M) Work (W) Heat loss Radiation ( R ) Convection ( C) Evaporation ( E )

Heat stress M + W + C + R = E V dilatation of skin vessels = Sweating = Loss of Cl = heat cramps (abd. / thigh ). V constriction of central vessels = Heat exhausion ( fatigue, loss of concentration, tendency to sleep & indigestion)

Sun stroke Exposure still present = No water = Fatigue of sweat glands = Humidity = Heat production = Body temperature = Sun stroke. Prevention and control: Source: substitution, isolation, enclosure or ventilation. Environment: ventilation. Workers: Pre-employment (CVD, Ht or PVD) Periods of rest (water, NaCl, Vit C) Personal protection Health education & nutrition

Atmospheric pressure At sea level = 76 mmHg “14.7 pounds/inch) Descent: Capillary rupture. Hemorrhage inside closed cavities Severe pain Sub-conjunctiva hemorrhage. Bottom: Nitrogen narcosis Oxygen poisoning

Ascent: Caison s disease lung emphysema Embolism CNS, heart, lung..etc. Extremities joints pain Skin itching. Prevention & control: Pre-employment: Young healthy, No resp. or cardiac dis., Good lung function, proper nutrition. -Personal protective measures. -Treatment

Noise Non auditory Annoyance, anxiety. Performance is highly affected. Physiological effects. Auditory 1- Air conduction deafness Rupture of the drum. Dislocation of ossicles. 2-Nerve conduction deafness Temporary ( due to fatigue) Permanent (due to atrophy)

Prevention and control: Source: Substitution, Isolation, Enclosure & Maintenance. Environment: Noise proof substances. Workers: Exclude positive family history. Audigrams Health education. Protective measures (ear plugs)

Dust diseases Dusts are solid particles produced in the course of processes such as crushing, grinding, blasting or demolition. Factors affecting effects -Concentration of dusts -Size -Length of exposure -Type -Susceptibility

Effects Skin dermatitis Eye conjunctivitis, ulcers Teeth erosion Nose Irritation Lung Pneumoconiosis Systemic Poisoning & cancers

Pneumoconiosis Major Minor Benign Hypersensitivity Silicosis Anthracosis Baritosis Hay fever Asbestosis Byssinosis Siderosis Asthma Coal miners. Bagassossis Talcosis

Inorganic Dust silicosis Inhalation of silica dust (rock, iron, coal, granite &glass) Fibrosis + military nodules Dyspnea Decrease chest capacity Increased susceptibility

Asbestosis Asbestos silicates of Mg & Fe Lung fibrosis Carcinoma Emphysema Bronchopneumonia Pul. T.B.

Byssinosis Cotton industry Stages Monday fever tightness, sore throat, dry cough & low grade fever. Second stage: +other days, asthma, bronchitis Third stage: + emphesema

Metals Manganese parkinsonism Mercury stomatitis & tremors Phosphorus muscle contraction, glands hypersecrtion, decrease HR, RR Lead decrease IQ & toxicity

Gases I- Asphyxiants Hypoxia, hypercapnea & acidosis. a- Simple asphyxia: Nitrogen, Hydrogen, carbon dioxide, helium & argon. b- Chemical asphyxia: Carbon monoxide, nitrous group, hydrogen sulphite & cyanides,

Irritant gases URT e.g. arcaldehyde = lacrimation, sore throat, sneezing & laryngitis (warning gas). MRT e.g. Chlorine, sulpher dioxide = acute tracheitis, acute bronchitis & bronchiolitis, cough & dypsnea. LRT e. g. ozone, nitrose oxide, phosogene = pulmonary edema & death.

III- Toxic gases e.g. PH3, arsine & stibine = affect every organ