The worsening of interior air quality caused by hazardous chemicals and other pollutants is known as indoor air pollution. It is basically due to the methods of heating and cooking that include burning biomass fuel, such as wood, charcoal, dung, and agricultural residue, in enclosed spaces with inadequate ventilation. Serious health hazards are faced by millions of people, particularly women and children. This issue affects around 3 billion people worldwide who live in developing nations. According to the World Health Organization (WHO), indoor air pollution from cooking kills 3.8 million people every year. According to the Global Burden of Disease report, 1.6 million people died in 2017 due to indoor air pollution. This article will explain Indoor Air Pollution which will be helpful in preparing the Environment Syllabus for the UPSC Civil Service exam.

Indoor Air Pollution - Types

Rural

• Rural communities, where households still use conventional energy sources like firewood, charcoal, and cow dung for heating and cooking, are those where interior pollution poses the biggest concern.
• Burning these fuels results in excessive exposure because it fills the little dwelling with a lot of smoke and other air pollutants.
• Due to their increased inside time and exposure to smoke, women and children are the populations most at risk.
• The four most dangerous contaminants in the smoke from biofuels are formaldehyde, polycyclic organic matter, carbon monoxide, and particulates, however, many hundreds of different chemical agents have been found.

Urban

Exposure to indoor air pollution has grown in urban areas for a number of reasons, including

• Construction of buildings with tighter seals;
• Decreased ventilation;
• Using synthetic materials for construction and furnishings;
• The use of chemical products, insecticides, and household care items.
• Indoor air pollution might start inside the building or be brought in from the outside.
• Several other pollutants, besides lead, carbon monoxide, and nitrogen dioxide, have an impact on the quality of the air.

Indoor Air Pollution - Causes And Effects

Volatile Organic Compounds (VOCs)

• Volatile organic compounds (VOCs) are gases that are released as a result of specific solids or liquids.
• Many different compounds are included in VOCs, some of which may have negative short- and long-term health impacts.
• The primary sources of volatile organic compounds are perfumes, hairsprays, furniture polish, glues, air fresheners, moth repellents, and other goods.
• They result in poor coordination, headaches, nausea, throat, eye, and nose irritation.
• The liver and other organs may get damaged from long-term exposure to volatile organic compounds.

Tobacco Smoke

• Smoke emits a variety of harmful chemicals and is carcinogenic.
• Burning eyes, nose, and throat irritation, cancer, bronchitis, severe asthma, and a decrease in lung function are all possible side effects.
• Secondhand smoke is tobacco smoke that has an impact on individuals other than the "active" smoker.
• There are gaseous and particle components to secondhand smoke, with amounts of carbon monoxide and very minute particulates posing significant health risks (fine particular matter at especially PM2.5 size, and PM10).
• They enter the lung's bronchioles and alveoli. Eliminating indoor smoking is the only surefire way to enhance the indoor air quality in terms of secondhand smoke.
• E-cigarette usage inside the home also raises particulate matter levels in the air.

Indoor Combustion

• Indoor combustion, such as that used in cooking or heating, is a significant contributor to indoor air pollution and is linked to serious health effects and early mortality.
• Air pollution results from hydrocarbon burns. Both biomass and different kinds of fossil fuels can contribute to pollution, but some fuels are more destructive than others.
• Black carbon particles, nitrogen oxides, sulphur oxides, and mercury compounds are just a few of the emissions that might result from an indoor fire.
• Approximately 3 billion people use open flames or crude cook burners to prepare their meals.

Biological Pollutants

• Biological pollutants include certain bacteria, fungi, parasites, pet hair, mites, and pollen from plants.
• The majority of them are allergens and can lead to hay fever, asthma, and other allergic conditions.

Radon

• The radioactive decay of radium produces the radioactive gas known as radon, which is invisible and radioactive.
• They can be identified in specific building materials or in the geological formations that lie beneath structures.
• The most common major indoor air hazard, radon is likely to be to responsible for tens of thousands of lung cancer deaths each year.
• As a heavy gas that enters structures as a soil gas, radon tends to build up at the lowest level.
• Additionally, radon can enter a structure through drinking water, specifically from bathroom showers.

Carbon monoxide

• Carbon monoxide (CO) is one of the most hazardous indoor air pollutants.
• It is a by-product of incomplete combustion and is a colourless, odourless gas.
• Tobacco smoke, fossil fuel-powered space heaters, malfunctioning central heating furnaces, and exhaust from vehicles are common sources of carbon monoxide.
• High quantities of carbon monoxide can cause nausea, unconsciousness, and death by depriving the brain of oxygen.

Asbestos

• Many typical building products used in construction before 1975, including some floor tiles, ceiling tiles, shingles, fireproofing, heating systems, pipe wrap, taping muds, mastics, and other insulation compounds, contain asbestos.
• Unless the construction materials are disturbed, such as by cutting, sanding, drilling, or remodelling the building, large emissions of asbestos fibre typically don't happen.
• Asbestos fibres can be dispersed into the air during the removal process, thus it's not always ideal to remove things that contain asbestos.
• The air gets contaminated with microscopic fibres when asbestos-containing material is destroyed or disintegrates.
• Long-term exposure to asbestos fibres is linked to an increased risk of lung cancer, particularly the specific type known as mesothelioma.

Formaldehyde

• Carpets, particle boards, and insulating foam are the main sources of formaldehyde.
• In addition to allergies, it irritates the eyes and nose.

Measuring Standards of Pollutants

• Air quality is measured using air quality indicators like the “Air Quality Index”. PM 2.5 and PM 10 are the most often used air quality indicators.
• The particles are measured in micrograms per cubic metre.
• PM 2.5 denotes the concentration of microscopic particles with a diameter of fewer than 2.5 microns, while PM 10 denotes the concentration of particles with a diameter of fewer than 10 microns.
• India also monitors two more pollutants: lead and ammonia. A number of less than 50 on the AQI scale is deemed safe.
• Instruments used to measure Air quality are PCE-RCM 05, PCE-HFX 100, PCE-RCM 8.
• The majority of the particles are generated as a result of complex chemical processes involving sulfur dioxide and nitrogen oxides.
• Automobiles, factories, power plants, and other sources emit these pollutants.

Indoor Air Pollution - Control Measures

Public Awareness

• Raising people's knowledge of the problem and the grave risk it presents to their health and welfare is one of the most crucial measures in the prevention of indoor air pollution.
• People should discover diverse approaches to decreasing exposures with better kitchen management and at-home child safety with the use of education.
• Additionally, the usage of alternate, cleaner energy sources should be made known to the public as a viable alternative to the direct combustion of biomass fuel.
• To assure their commitment and raise their understanding of the negative impacts of indoor air pollution on health, the stakeholders must include not only members of the public but also politicians and administrators.

Change in Fuel Use Pattern

• Fuel consumption is influenced by habit, accessibility, and most crucially, affordability.
• Since it is the cheapest and simplest option available to them, the majority of low-income families currently only use direct combustion of biomass fuels for their cooking needs.
• However, this situation could be changed by encouraging the use of cleaner energy sources, such as gobar gas, which uses cow dung to produce gas for cooking.

Modification in Cooking Stove’s Design

• Traditional cooking stoves that leak and emit smoke should be replaced with more energy-efficient stoves that emit no smoke and have a place for interior pollutants to depart (such as a chimney).
• One excellent illustration is the stove developed by the National Biomass Cookstoves Initiative of the Ministry of New and Renewable Energy under a Special Project on Cookstoves during 2009–2010.
• The main objective is to enhance the availability of clean and efficient energy for the country's energy-deficient and poorer regions.

Improvement in Ventilation

• Proper ventilation should be a priority when building a home; for inadequately ventilated homes, methods like a window above the stove and cross ventilation through doors should be implemented.

Intersectoral Coordination and Global Initiative

• Intersectoral cooperation and global action are required if indoor air pollution is to be reduced.
• These efforts must come from the health, energy, environment, housing, and rural development sectors among others.

Indoor Air Pollution - Related Initiatives

• Pradhan Mantri Ujjwala Yojana: Pradhan Mantri Ujjwala Yojana (PMUY), a government initiative, provides LPG connections to BPL households (by the Petroleum Ministry and part of Swatch Bharat Abhiyaan).
• Graphene-based Sensor: A sensor based on graphene has been created by scientists to find indoor air pollution.
• Neerdhur: The National Environmental and Engineering Research Institute (NEERI) has created the revolutionary multi-fuel stove "Neerdhur" for residential use.
• HEPA Filters (High Energy Particulate Arrestor): Indoor air filters are made of HEPA (High Energy Particulate Arrestor) filters. However, they only apply to particle matter.
• WAYU (Wind Augmentation Purifying Unit): CSIR-NEERI produces WAYU (Wind Augmentation Purifying Unit). Along with UV lights and activated carbon (charcoal) for eliminating harmful gases, it features filters for removing particulate matter.
• Sustainable Development Goal, 7: SDG 7 aspires to guarantee that everyone has access to affordable, dependable, sustainable, and modern energy.

Conclusion

Even though there is evidence that indoor air pollution is on the rise in India and that it is linked to higher rates of morbidity and mortality, more research is still required to determine the extent of indoor pollution exposure and to support the link between indoor pollutants and diseases like cancer, tuberculosis, cataract, asthma, and cardiovascular disease. Effective interventions are also required right now, from education to altering fuel usage patterns to constructing homes and stoves properly to a committed and determined intersectoral collaboration to advance public health.

FAQs

MCQs

1. Which of the following is a primary source of indoor air pollution?

A) Traffic emissions
B) Household cleaning products
C) Industrial emissions
D) Outdoor dust storms

2. Which of the following measures can help in reducing indoor air pollution?

A) Using air purifiers
B) Keeping windows closed
C) Burning incense indoors
D) Using non-ventilated space heaters

3. Which group is most vulnerable to the effects of indoor air pollution?

A) Middle-aged adults
B) Young healthy adults
C) Children and the elderly
D) Office workers

4. Which of the following is a direct health effect of indoor air pollution?

A) Increase in body temperature
B) Respiratory problems
C) Enhanced vision
D) Muscle gain

5. Which of the following is NOT a common pollutant found in indoor air?

A) Carbon monoxide
B) Radon
C) Nitrous oxide
D) Formaldehyde

GS Mains Questions and Model Answers

Q1: Discuss the sources of indoor air pollution in India and its impact on public health. How can these issues be addressed?

Answer: Indoor air pollution in India is primarily caused by the burning of solid fuels like wood, coal, and biomass for cooking, as well as tobacco smoke, pesticides, and household products. This pollution leads to respiratory diseases, cardiovascular issues, and in some cases, cancer. Vulnerable groups, especially children, the elderly, and people with pre-existing conditions, are at a higher risk. To address these issues, India must promote cleaner cooking technologies, improve ventilation in homes, and raise awareness about the health risks associated with indoor air pollution. Policies like providing clean energy alternatives and stricter regulation on household products could significantly mitigate the problem.

Q2: Evaluate the role of government regulations in controlling indoor air pollution. What are the key challenges in implementing these regulations?

Answer: Government regulations, such as standards for indoor air quality and the promotion of clean cooking technologies, play a crucial role in controlling indoor air pollution. These measures can reduce exposure to harmful pollutants and protect public health. However, key challenges include enforcement in rural and remote areas, where clean technologies may be unaffordable or inaccessible. Additionally, the lack of awareness and financial support for low-income households poses a barrier to widespread implementation. Effective solutions will require a multi-pronged approach involving policy support, community outreach, and the availability of cleaner alternatives.

Q3: Examine the relationship between indoor air pollution and climate change. How can addressing indoor pollution help mitigate climate change?

Answer: Indoor air pollution contributes to climate change through the release of carbon dioxide, black carbon (soot), and other greenhouse gases from the burning of fossil fuels and biomass. These emissions add to the overall warming of the planet. Addressing indoor pollution by promoting clean energy alternatives for cooking and heating can significantly reduce these emissions. Additionally, reducing the use of products that emit volatile organic compounds (VOCs) will help lower the concentration of ground-level ozone, which is a greenhouse gas. Therefore, tackling indoor pollution is an important strategy for both improving public health and mitigating climate change.

Previous Year Questions on Indoor Air Pollution

1. UPSC CSE Prelims 2019:

Question: Which of the following is the most common indoor air pollutant?

A) Radon
B) Carbon monoxide
C) Particulate matter
D) Ozone

Answer: (B)

Explanation: Carbon monoxide is one of the most common indoor pollutants, particularly from combustion sources like stoves and tobacco smoke.

2. UPSC CSE Mains 2020 (GS Paper 3):

Question: "Analyze the sources of indoor air pollution in urban and rural areas of India and suggest solutions to improve air quality indoors."

Answer: In urban areas, indoor air pollution is primarily caused by the burning of solid fuels in households and by emissions from household products like paints and cleaning agents. In rural areas, biomass burning for cooking is a major source. Solutions include promoting clean cooking stoves, improving ventilation, and creating awareness about the risks of indoor pollution. Government initiatives should focus on providing affordable clean energy alternatives and stricter regulation on hazardous products.