occupational health 23 nov 2012

Abdelmageed Osman Musa

Community Medicine Specialist

04/08/23 Occupational Health 2

History of Occupational H.


Cont. History of Occupational H

Bernardino Ramazzini (1633-1714) Italy De Morbis Artificum Diatriba - (1700)


History of Occup. H. in Sudan

1908 – Child labor Act

1949 – Factory and Workshops Act

1968 – Establishment of Occup. H. Dept.


Promotion and maintenance of the highest degree of physical, mental and social

well-being of all workers in all occupations

Definition of Occupational Health


The importance (rationale) of studying Occup. H.

Annual deaths > 200 000. Annual diseases > over 120 millions New introduced chemicals Affects economics directly Chemical epidemics are serious Industrialization is growing – Developing countries use pollutant

industries.


Types of Occupational Hazards

1. Physical2. Chemical3. Biological4. Mechanical5. Psychosocial

Physical Hazards


Effects of HeatDirect effects of heat exposure: Burns Heat exhaustion Heat stroke Heat cramps

Indirect effects of heat: Decreased efficiency Increased fatigue Enhanced accident rates04/08/23 Occupational Health 10

Sources of heat

Climate Foundries Ovens

It is a hazard mainly for: Construction workers Foundry workers Textile workers04/08/23 Occupational Health 11

Accepted levels of temperature

Measured by the Wet Bulb Globe Temperature (WBGT)

It measures the radiant

temperature

Accepted temperature

20 – 27° C04/08/23 Occupational Health 12

Wet Bulb Globe


Effects of Cold on health:

Effects are due to vasoconstriction: Chilblains (cold + humidity) Erythrocaynosis discoloration on the legs and

thighs (chronic exposure of cold) Immersion foot (a painful disorder of the foot)

Frostbite (damage to skin and other tissues due to freezing)



ChilblainsErythrocaynosis

Immersion foot

Frostbite

Light

Effects of poor illumination: Eye strain Headache Miner’s nystagmus

Effects of intense light: Visual fatigue Blurring of vision


Measuring Light

Light meters Intensity of light is measured according to the

function of the worker Unit of measuring is the lux (symbol: lx) Examples:

Normal Office Work, Study Library, 500 Supermarkets, Mechanical Workshops, 750


Noise

Effects of noise: Auditory effects (temporary or permanent

hearing loss) Non-auditory effects:

Nervousness Fatigue Difficult communication Hypertension Cardiovascular diseases


Recommended levels

80 – 90 dB(A) for workplaces 40 hr/week Noise levels could be reduced by ear plugs

or ear muffs


Noise Measurements

Noise is measured by Sound level meters Occupational hearing loss is detected by

audiometers (The 4000 Hz Dip)


Vibration

Vibrations encounter in work with drills and hammers

It may cause disorders and injuries of the joints, the hands and elbow


Ultraviolet radiation

It is affects mainly welders through radiation Such radiation affects the eyes causing

intense conjunctivitis and keratitis (Welder’s Flash)


Ionizing radiation

It is increasing in medicine and industry It had different effects on health:

Cancers Genetic changes Malformations Sterility ... Death


Chemical Hazards


1. Local Actions

Primary irritant chemicals cause: Dermatitis Eczema Cancers

Absorbed Chemicals (aromatic nitro and amino compounds) may cause systematic effects to some organs (hepatotoxicants, neurotoxicants ..)


2. Inhalation of chemicals

i. Dust Dust particles < 10 microns settle on the

ground but small particles remain in the air Dust is released during crushing, loading,

grinding .. Inorganic dusts (silica, coal, asbestos ..) Organic dusts (cotton dust, bagasse dust.

grain dust ...)


Main diseases caused by dust

Byssinosis (cotton textile factories) Bagassosis (sugar cane factories) Silicosis (construction works, foundries ..) Asbestosis (asbestos manufacturing) Farmer’s lung (inhalation of grain dusts ..) Anthracosis (coal workers)


ii. Gases

Simple gases (Oxygen, hydrogen) Asphyxiating gases (carbon monoxide,

cyanide, sulphur dioxide, chlorine) Anesthetic gases (chloroform, ether ..)


iii. Metals

Lead (the most common poisoning) Antimony Arsenic Beryllium The most common mode of entry is inhalation

of dusts and vapors Metal poisoning respond to cessation and

treatment



Solvents

Benzene

Acetone

Chloroform

Biological Hazards


Biological Hazards

Macro-organisms: Wild animals Scorpions, snakes ...

Microorganisms: Brucellosis Tetanus Anthrax Viruses (HIV, Hepatitis B ..)


Mechanical Hazards


1. Accidents in industry

Human factors: Physical Psychosocial Sex (males ↑) - Age (young age ↑) Time and duration of work Experience Carelessness, overconfidence Slow cerebration Use of drugs and alcohol

04/08/23 34Occupational Health

Environmental factors of Accidents in industry

Unsafe machines Noise Poor illumination Poor housekeeping Unsafe tools Unsafe buildings

04/08/23 35Occupational Health


2, Ergonomic disorders


Ergonomics

Ergonomics: Adjustment of Man & Machine”

Ergo-friendly tools: Tools which reduce the stresses or problems resulting work


Factors of Psychosocial hazards

Lack of job satisfaction Insecurity Poor interpersonal relations Work pressure Poor management Poor incentives


Psychological & behavioural changes

Aggressiveness, Anxiety, Depression, Addiction Sickness absenteeism Accidents Systemic disorders


Organic disorders

Hypertension, headache, body-ache, peptic ulcers, asthma, diabetes, heart disorders, etc.


Thank you

Ref:• Park’s Textbook of Preventive and

Social Medicine

• Lecture notes on occupational health

• Handout

• Internet

occupational health 23 nov 2012

Health & Medicine