Environmental Chemistry

Air Pollution

The existence of chemicals in the environment detrimental to the safety of humans and other living organisms, or that inflict damage to the ecosystem or materials, is air pollution. Gases (such as mercury, carbon monoxide, sulphur dioxide, nitrous oxides, methane, and chlorofluorocarbons), particulates (both organic and inorganic), and biological molecules occur in various types of air contaminants. Air exposure can cause humans to suffer from infections, asthma, and even death; it can also damage other living species, such as livestock and food crops, as well as harm the natural environment.

A mixture of gases that together form the atmosphere is responsible for maintaining all living things; the imbalance which is caused by the rise or decrease in the percentage of these gases may be hazardous to survival. As per The Blacksmith Institute World’s Most Contaminated Areas survey, indoor air pollution, and low urban air quality are two of the worst toxic pollution concerns in the world.

Air Pollution

                                                                                    Air Pollution


The material in the environment that may have harmful effects on humans and the ecosystem is an air pollutant. The substance can be strong crystals, liquid droplets, or gases. A pollutant can be of natural or man-made nature. Pollutants are categorized as secondary or primary. Some of the pollutants are:

  • Carbon Dioxide: It is the leading pollutant and the worst climate pollutant’ because of its function as a greenhouse gas. Carbon dioxide is a natural component of the environment, vital to plant life which is exhaled out by human beings. The rise in carbon dioxide in the earth’s atmosphere is accelerating.
  • Sulphur Dioxide: Sulphur Dioxide is produced in numerous manufacturing processes and by volcanoes. Coal and petroleum also produce sulphur compounds, and their combustion produces sulphur dioxide. In the presence of a catalyst such as nitrogen dioxide, further oxidation of sulphur dioxide typically forms sulphuric acid that is responsible for acid rain.
  • Carbon Monoxide: Carbon Monoxide is a poisonous, odourless, colourless gas. It is a fuel-burning gas, such as natural gas, coal, or wood. The amount of carbon monoxide which gets emitted into our atmosphere corresponds to vehicular emissions. It causes the creation of a smog type in the air which leads to many lung disorders and natural environment and animal disturbances.
  • Particulate Matter: Fine particles, or atmospheric particulate matter, are tiny solid or liquid particles that get trap in a gas. In comparison, aerosol applies to particles and gas together. Originating from volcanoes, dust storms, woodland and grassland burns, living trees, and sea spray, some particles exist naturally. Significant volumes of aerosols are the result of human operations, such as the combustion of fossil fuels in automobiles, power plants, and other manufacturing processes. Anthropogenic aerosols, averaged globally, actually account for around 10 per cent of our atmosphere, those made by human activities.

Effects of Air Pollution

Health problems may include trouble breathing, wheezing, coughing, asthma, and deteriorating respiratory and cardiac conditions. Children whose age is less than five years that live in developing countries are the most vulnerable population in terms of total deaths attributable to indoor and outdoor air pollution.

  • Mortality: In 2014, the World Health Organisation reported that air pollution causes the premature deaths of some 7 million individuals worldwide per year. The figure is about 8.8 million. India has the highest number of deaths due to air pollution. According to the World Health Organisation, India also has more asthma deaths than any other country.  In the Los Angeles Basin and San Joaquin Valley of Southern California, a recent economic analysis of the health effects and indirect costs of air pollution reveals that more than 3,800 individuals die prematurely each year because air pollution levels exceed federal requirements. Diesel exhaust (DE) is a significant contributor to air emissions from combustion. In many human laboratory trials, DE relates to acute vascular dysfunction and clot formation using a good exposure chamber setup.
  • Cardiovascular Disease: Exposure to indoor air pollution is a risk factor that corresponds with increased overall mortality from cardiovascular accidents. Air pollution is also emerging as a risk factor for stroke, particularly in developed countries with the highest levels of pollutants.
  • State-Wide Trends: In terms of PM 2.5 concentrations, India has 14 out of the 15 most toxic cities in the country, according to the WHO. Delhi, Patna, Agra, Muzaffarpur, Srinagar, Gurgaon, Jaipur, Patiala, and Jodhpur are other Indian cities that report very high amounts of PM2.5 contaminants. The Air Quality Index (AQI) is a number to report the level of air pollution. It generally indicates the level of air pollution in a particular city. The AQI of Delhi was put by the Framework of Air Quality and Weather Forecasting and Research under the “severe-plus category” when it hit 574.

How To Reduce Air Pollution

To decrease air emissions, numerous pollution management technology and techniques are available. Land-use planning at the most specific stage is likely to include zoning and planning of transport infrastructure. Land-use planning is an important aspect of social policy in most developing nations. It means that users of land are successful for the benefit of the broader economy and community as well as to protect the environment.

Because the burning of fossil fuels such as coal and oil produces a significant proportion of air emissions. Eliminating these fuels will significantly reduce air pollution. The potential of titanium dioxide to decrease air pollution. Ultraviolet light releases free electrons from the substance and thereby creates free radicals that break down VOCs and NOx gases. One form is super hydrophilic. The transition to green energy is a very efficient way of mitigating air emissions.

An electrostatic precipitator (ESP) or electrostatic air cleaner is a particulate collection system that uses the force of an induced electrostatic charge to extract particles from a flowing gas (such as air). Electrostatic precipitators are highly effective filtration systems that minimally obstruct gas flow through the device and can extract small particles from the air stream quickly, such as dust and smoke. Wet scrubbers are a type of technology for pollution control. The phrase defines a collection of devices that use emissions from or from other gas sources from a furnace flue gas.

FAQs about Air Pollution

Q.1 Explain Acid Rain?

Ans. Acid rain, or acid deposition, is a general term that encompasses any type of acid product precipitation, such as sulfuric or nitric acid, which, in wet or dry forms, falls from the atmosphere to the ground. This can involve acidic rain, snow, fog, hail, or even ashes.

Q.2 Explain Global Warming?

Ans. for the last one or two decades, the pattern of rising average air temperatures near the Earth’s surface. Since the mid-20th century, climate scientists have control and transparency measurements of different environmental patterns (such as temperatures, precipitation, and storms) and specific climate factors (such as ocean currents and the chemical makeup of the atmosphere).

Q.3 What is the difference between air pollutants and toxic air pollutants?

Ans. Toxic air pollutants (or Hazardous Air Pollutants, HAPs) are different from air pollutants. Air toxics cause cancer or other serious health effects, such as damage to the respiratory or nervous systems. Toxic air pollutants may exist as particulate matter or as vapours (gases). Air toxins include metals, particles, and certain vapours from fuels and other sources.

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