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Impacts of pollutants on human health: Humans always need to interact with the environment on a daily basis. This interaction with the environment leads to some environmental issues like pollution, global warming, climate change, deforestation etc.
Pollutants Impacts on Human Health
For all environmental issues, pollution is the only cause of the remaining issues. As we know that pollution is the addition of unwanted substances in a concentration that has an adverse effect on organisms and the environment and the unwanted substances in a concentration is called Pollutants.
All pollutants have an adverse effect on human health. So, we will discuss here, the impact of air and water pollutants along with radiation, soil and noise pollution.
Major Air Pollutants
Carbon dioxide is one of the major gases which contributes to air pollution. It is mainly produced during the combustion of fuel in factories, power stations, household etc. The increasing CO2 in the atmosphere is likely to have the following effects:
- A rise in atmospheric temperature or global warming due to the greenhouse effect. Also causes climate change.
- Reduced productivity of the marine ecosystem. This is due to the fact that water in the oceans would be more acidic due to increased concentration of CO2 in the air, which dissolves in the water.
- Due to Global warming, the increased surface temperature would cause melting of continental and mountain glaciers and thus would cause flooding of coastal areas of some countries.
It is produced by the burning of coal in powerhouses and automobiles (car, trucks etc.). It causes chlorosis and necrosis of plants, irritation in eyes and injury to the respiratory tract (asthma, bronchitis) in humans responsible for discolouration and deterioration of buildings. A high concentration of sulphur dioxide in the atmosphere dissolves in raindrops to form sulphuric acid which causes acid rain.
Carbon monoxide is produced as a result of incomplete combustion of fossil fuels like coal, petroleum and wood charcoal. Automobiles using diesel and petroleum are the major sources of carbon monoxide which get added to the atmosphere. Carbon monoxide is more dangerous than carbon dioxide. It is a poisonous gas which causes respiratory problems. When it reaches the bloodstream, it replaces oxygen due to its high affinity for haemoglobin. It also causes giddiness, headache and interferes with the normal function of the heart.
Upon heating, rocks, soils and minerals that contain fluorides, give out hydrogen fluoride gas. This is an extremely toxic gas, which causes serious injury to livestock and cattle.
Oxides of Nitrogen
A few oxides of nitrogen, such as nitric oxide (NO), nitrous oxide (N2O) and nitrogen dioxide (NO2) are produced by natural processes as well as from thermal power stations, factories, automobiles and aircraft (due to burning of coal and petroleum). They reduce the oxygen-carrying capacity of blood, may cause eye irritation and skin cancer in human beings.
Smog is a mixture of smoke, dust particles and small drops of fog. Smog may cause necrosis and develop a white coating on the leaves (silvering) of plants. In human beings and animals, it may cause asthma and allergies.
Aerosol Spray Propellants
Suspended fine particles in the air are known as aerosols. Aerosols contain chlorofluorocarbons (CFCs) and fluorocarbons used in refrigerants and aerosol cans. They cause depletion of the ozone layer.
Domestic Air Pollutants
Smoke from cigarettes, Biri, cigar and other such objects using burning tobacco, burning of coal, firewood, cow dung cakes, kerosene oil and liquefied gases are major domestic pollutants. The common pollutant gases emitted during the domestic burning of coal, kerosene oil, firewood, cow dung cakes, etc. are carbon monoxide (CO), carbon dioxide (CO2), sulphur dioxide (SO2), etc. The pollution due to these pollutants causes suffocation, eye and lung diseases and low visibility.
Air Pollutants Impacts
Major effects of air pollutants on human health, plants and other animals is given below:
Some major air pollutants, their sources and effects
|Carbon compounds (CO and CO2)||Automobile exhausts, burning of Wood and coal||– Respiratory problems
– Greenhouse effect global warming and climate change
|Sulphur Compounds (SO2 and H2S)||Power plants and refineries, Volcanic
|· Respiratory problems in humans
· loss of chlorophyll in plants (chlorosis)
· Acid rain
|Nitrogen Compound (NO and N2O)||Motor vehicle exhaust, atmospheric reaction||· Irritation in eyes and lungs
· Low productivity in plants
· Acid rain damages material (metals and
|Hydrocarbons (benzene, ethylene)||Automobiles and petroleum industries||· Respiratory problem
· Cancer-causing properties
|SPM (Suspended Particulate matter) (Any Solid or liquid particles suspended in the air, (fly ash, dust, lead)||Thermal power plants, construction activities, metallurgical processes and automobiles||– Poor visibility, breathing problems
– Lead interferes with the development of red blood cells and causes lung diseases and cancer
– Smog (smoke+fog) formation leads to poor visibility and aggravates asthma in patients
|Fibres (Cotton, wool)||Textile and carpet weaving industries||– Lung disorders|
Impacts of Water Pollutants on Human Health
River, lake and seawater may be polluted in many ways:
- Domestic sewage discharged into rivers from areas located on its banks.
- Industrial wastes effluents from urban areas containing a high concentration of oil, heavy metals and detergents.
- Minerals, organic wastes and crop dusting from agricultural fields with phosphate and nitrogen fertilizers that reach lakes, rivers and sea (water becomes deoxygenated and poisonous, thus, cannot support aquatic life).
- Chemical fertilizers, pesticides, insecticides, herbicides and plant remains.
- Industrial wastewater containing several chemical pollutants, such as calcium, magnesium, chlorides, sulphide, carbonates, nitrates, nitrites, heavy metals and radioactive waste from the nuclear reactor.
- Excretory wastes of humans and animals in water bodies
- Disposal of urban and industrial waste matter into water bodies
Some major disturbances in the ecosystem due to water pollution
|Nitrates, phosphates, ammonium salts||Agricultural fertilizers, sewage, manure||Plant nutrients||Eutrophication|
|Animal manure and plant residues||Sewage, paper mills, food processing wastes||Oxygen deficiency||Death of aquatic animals|
|Heat||Power plants and industrial cooling||Thermal discharge||Death of fish|
|Oil slick||Leakage from oil ships||Petroleum||Death of marine life due to non-availability of oxygen dissolved in water|
Fertilizers and pesticides are widely used in agriculture. Their excessive use for increasing agricultural yield has led to the phenomenon of eutrophication and biomagnification.
Some water pollutants, their sources and effect on human health
|Pollutant||Source||Diseases in humans|
|Lead||Industrial waste||Nervous disorders, Kidney failure, blood poisoning|
|Tin||Industrial dust||Affects central nervous system (CNS) Affects, vision|
|Mercury||Industrial discharge||Affects central nervous system and peripheral nervous system, kidney failure, Numbness of lips, muscles and limbs, Blurred vision|
|Arsenic||Industrial discharge||Respiratory and skin cancer, Nervous disorder|
|Nickel, Cadmium||Aerosols, Industrial dust, Industrial discharge||Pulmonary disorders, Dermatitis, Kidney disorders, Pulmonary and skeletal diseases|
|Uranium, Thorium, Cesium||Radioactive waste||Leucoderma, Skin cancer|
Impacts of Pollutants – Nuclear Radiation
Radiations emitted by nuclear substances or wastes (fallout) or from atomic power plant or an atomic explosion cause nuclear radiation. Nuclear wastes continue to emit radiation for a very long period.
Radioactive Iodine (iodine-131) and Strontium (Sr-90) are two nuclear wastes from an atomic explosion and may cause cancer of thyroid and cancer of bone narrow/ respectively. By entering the food chain, they also get accumulated in high concentration in the body of the top consumer causing a harmful effect on the health of both humans and animals.
Harmful effects of soil pollution
- Decrease in irrigated land thereby reduction in agricultural production.
- Decrease in soil productivity.
- Carryover of pollutants into the food chain.
- Damage to landscape
Effects of Noise pollution
- Inability to sleep, slow recovery from sickness.
- Irritability and interference in communication.
- Temporary loss of hearing, earache, sometimes even leading to permanent deafness.
- Inability to concentrate, headache.
- Ringing of ears (a feeling, sound coming from within the ear in a very quiet environment).
- Increased blood pressure, irregular heartbeat.
The impacts of pollutants on human health have briefly discussed here with important points. We advise you to refer some other study materials, books and internet. If you find any conceptual or human errors or missing any important points or topics, feel free to inform us either by commenting or email.