PRESENTED BY :-Dr SAKSHI KAUR CHHABRA3ND YEAR POST GRADUATEDEPARTMENT OF PUBLIC HEALTH DENTISTRY

AIR, NOISE AND RADIATION POLLUTION

POLLUTIONThe contamination of air, water, or soil by substances that are harmful to living

organisms. Pollution can occur naturally, for example through volcanic eruptions, or as the result of human activities, such as disposal of industrial waste. 

AIR POLLUTIONAir pollution is one of the present – day problems throughout the world. Air pollutants may be either emitted into the atmosphere or formed within the

atmosphere itself.

1. Primary air pollutants

2. Secondary air pollutants

3. Gaseous air pollutants

4. Particulate air pollutants

SOURCES OF AIR POLLUTION1)AUTOMOBILES

2) INDUSTRIES

3) DOMESTIC SOURCES

4) TOBACCO SMOKE

5) MISCELLANEOUS

NATURAL SOURCES PESTICIDE SPRAYING

AIR POLLUTANTS More than 100 substances which pollute air have been identified. The important ones are

1. Carbon monoxide2. Carbon dioxide3. Hydrogen sulphide4. Sulphur dioxide5. Sulphur trioxide6. Nitrogen oxides7. Fluorine compounds8. Organic compounds (e.g., hydrocarbons, aldehydes, ketones, organic acids)

Pollutants may be in the form of solids, liquids (vapours) or gases. The combination

of smoke and fog is called "smog".

EFFECTS OF AIR POLLUTIONAir pollution can affect by two

ways :

[A] HEALTH ASPECTS

[B] SOCIAL AND ECONOMIC ASPECTS

[A] HEALTH ASPECTS The health effects of air pollution are immediate and delayed. The immediate effects are borne by the respiratory system, the resulting

state is acute bronchitis. If the air pollution is intense, it may result even in immediate death by suffocation. This has taken place in the air pollution epidemic which occurred in London in 1952.

The delayed effects most commonly linked with air pollution are chronic bronchitis, lung cancer, bronchial asthma, and respiratory allergies.

[B] SOCIAL AND ECONOMIC ASPECTS

[1]These comprise destruction of plant and animal life, damage to buildings.

[2]Air pollution also reduces visibility in towns.

PREVENTION AND CONTROL OF AIR POLLUTANTS

The WHO has recommended the following procedures for the prevention and control of air pollution :-

1) CONTAINMENT2) REPLACEMENT3) DILUTION4) LEGISLATION5) INTERNATIONAL ACTION

[1] CONTAINMENT Prevention of escape of toxic substances into the ambient air. Containment can be achieved by a variety of engineering methods such as

ventilation and air cleaning

[2] REPLACEMENT Replacing a technological process causing air pollution, by a new process that does

not cause Air pollution. Increased use of electricity, natural gas and central heating in place of coal have

greatly helped in smoke reduction.

[3] DILUTION Dilution is valid so long as it is within the self-cleaning capacity of the environment.

For example, some air pollutants are readily removed by vegetation. The

establishment of "green belts" between industrial and residential areas is an attempt

at dilution.

[4] LEGISLATIONAir pollution is controlled in many countries by suitable legislation, e.g., Clean Air

Acts.

[5] INTERNATIONAL ACTION To deal with air pollution on a worldwide scale, the WHO has established an

international network of laboratories for the monitoring and study of air pollution.

The network consists of two international centres at London and Washington, three

centres at Moscow, Nagpur and Tokyo and 20 laboratories in various parts of the

world. These centres will issue warnings of air pollution where and when necessary.

DISINFECTION OF AIR In recent years, disinfection of air has received much attention. The methods

employed are :

1. MECHANICAL VENTILLATION

2. ULTRAVIOLET RADIATION

3. CHEMICAL MISTS

4. DUST CONTROL

NOISE POLLUTIONNoise is often defined as "unwanted sound", but this definition is subjective because

of the fact that one man's sound may be another man's noise. Perhaps a better

definition of noise is : "wrong sound, in the wrong place, at the wrong time". Man is

living in an increasingly noisy environment.

SOURCES NOISE POLLUTION The sources of noise are many and varied. These are automobiles, factories,

industries, air-crafts etc. Noise levels are particularly acute near railway junctions, traffic round-abouts, bus

terminuses and airports. Use of pressure horns, recreational noise of loudspeakers with full volume during

festivities particularly at night are other sources of noise production. The domestic noises form the radios, transistors, TV sets - all add to the quantum of

noise in daily life.

EFFECTS OF NOISE POLLUTION

NOISE POLLUTION can affect by two ways :

[A]AUDITORY EFFECTS

[B] NON – AUDITARY EFFECTS

[A] AUDITARY EFFECTS(a) Auditory fatigue : Auditory fatigue is defined as a temporary loss

of hearing after exposure to sound. (b) It may be associated with side effects such as whistling and buzzing in the ears

[A] AUDITARY EFFECTS(b) Deafness : The most serious pathological effect is deafness or hearing loss. The victim is generally unaware of it in early stages. The hearing loss may be temporary or permanent.

[B] NON - AUDITARY EFFECTSa) INTERFERENCE WITH SPEECH

b) ANNOYANCE

c) EFFICIENCY

d) PHYSIOLOGICAL CHANGES

e) ECONOMIC LOSSES

CONTROL OF NOISE A variety of approaches may be needed to control noise These include :-

1) CAREFUL PLANNING OF CITIES

2) CONTROL OF VEHICLES

3) INDUSTRIES AND RAILWAYS OUTSIDE THE CITY

4) PROTECTION OF EXPOSED PERSON

5) LEGISLATION

6) EDUCATION

RADIATION

Radiation is energy that comes from a source

and travels through some material or through

space.

 Radiation is part of man's environment.

SOURCES OF RADIATION The sources of radiation to which man is exposed are divided into two groups :-

NATURAL MAN - MADE[1] COSMIC RAYS [1] MEDICAL AND DENTAL :- X-RAYS AND

RADIOISOTOPES

[2] ENVIRONMENTAL :- [2] OCCUPATIONAL EXPOSURE(A)TERRESTRIAL [3] NUCLEAR :- RADIOACTIVE FALL-

OUT(B) ATMOSPHERE [4] MISCELLANEOUS :-

[3] INTERNAL :- TV SETS, RADIOACTIVE DIAL WATCHES, ISOTOPE TAGGED

(A) POTASSIUM – 40 PRODUCTS, LUMINOUS MARKERS

(B) CARBON – 14

TYPES OF RADIATION

The term "ionizing radiation" is applied to radiation which has the ability to

penetrate tissues and deposit its energy within them.

Ionizing radiation may be divided into two main groups :

(1) electromagnetic radiations - X-rays and gamma rays

(2) corpuscular radiations - alpha particles, beta particles (electrons) and protons

BIOLOGICAL EFFECTS OF RADIATION

The biologic effects of ionizing radiation may be divided into two separate groups :-

SOMATIC

GENETIC

SOMATIC

GENETIC

IMMEDIATE

DELAYED

{1}RADIATION SICKNESS{2}ACUTE RADIATION SYNDROMES

{1} LEUKEMIA{2} SHORTENING OF LIFE

{1} CHROMOSOME

MUTATION

{2} POINT MUTATION

PROTECTION FROM RADIATION

Unnecessary X- rays examinations should be avoided especially in case of children

and pregnant women. Improvements leading to dose reduction. Workers must wear a film badge or dosimeter which shows accumulated exposure to

radiation since last time the instrument was charged. Besides, periodic medical examinations, regular working hours and holidays must be

ensured to workers to maintain their state of health.