What we breathe everyday

An introduction to common pollutants in the city.

Every winter, as winds slow down and moisture in the air decreases across India, air pollution peaks leading to a spike in cases of respiratory diseases across the country. The primary cause of air pollution is open burning of fuel, garbage

Common pollutants

Particulate Matter (PM)

Particulate Matter (PM) are a mix of solid particles and liquid droplets in the air. Some particles such as smoke, dust, dirt etc. can be seen with the naked eye while others can only be detected using microscopes.

PM 10 are particles smaller than ten microns, which is thinner than the width of a human hair (50 - 70 micron). PM 2.5 are particles that are smaller than two-and-a-half microns.

Sources:

Liquid or solid particles in the air are considered particulate matter pollution. One of the main reason for the increasing PM in India is vehicular emission. Dust from construction materials such as sand, bricks, etc. too contribute to PM10 and PM2.5.

Industries that make use of fossil fuels and others such as refineries, cement, quarrying, and brickworks contribute a high amount of PM10 and PM2.5 particles. Wood stoves and burning wastes also contribute to emission.

Volcanic eruptions, dust storms, cyclones, bushfire, sea spray and pollens are natural sources of particulates. At home, cosmetics such as talcum powder and food items such as powdered spices contain particulates.

Effects:

Particulate matter, especially, PM2.5, cause more health issues among because they are invisible and go deep into the lungs and are absorbed by the blood stream. They can cause:

• allergy or hypersensitivity

• irritation of mucous membranes

• bacterial and fungal infections

• fibrosis

• cancer

• increased respiratory trouble such as aggravation of asthma. The risks are highest for sensitive groups such as the elderly and children.

• toxic effects by absorption of the toxic material such as lead, cadmium and zinc into the blood

Carbon Monoxide (CO)

Carbon Monoxide (CO) is a dangerous air pollutant. It has no colour or odour. Burning of fossil fuel produces the most amount of CO - that means vehicles and power plants are the main sources of this gas.

Sources:

In cities, CO comes from vehicles running on fossil fuels including cars, trucks and others. Kerosene stoves and LPG gas stoves, as well as leaf burning releases CO.

Effects:

Inhaling Carbon Monoxide reduces oxygen in blood and leads to dizziness, loss of consciousness and death.

Nitrogen dioxide (NO2)

​​​​​​​

Nitrogen dioxide or NO2 is a foul-smelling gas is also produced by vehicles and power plants during combustion.

According NASA’s 2015 satellite map of NO2, the level of NO2 is rising in India.

Sources: Combustion of fuels in vehicles, cooking gases, thermal power plants and industries.

Effects: The main effect of NO2 is on our respiratory system. It can cause wheezing, coughing, colds, flu and bronchitis. It also interacts with the chemicals in the atmosphere and causes acid rain.

Sulphur dioxide (SO2)

Sulphur dioxide is caused by combustion of fuels that contain sulphur, like coal. These react with other chemicals to form small particles that contribute to pollution

Sources: Burning of fossil fuels, metal industry, locomotives and ships, vehicles which burn fuel with higher sulphur content, volcano eruption.

Effects: The immediate effect is breathing trouble. Respiratory issues and even premature death can be caused by SO2. It also contributes to acid rain.

How to reduce exposure to pollutants

1. Use masks whenever possible: The recommended mask is N99 mask, which limits 99% of PM2.5 in the air reaching our lungs.

2. Use air purifiers of the right capacity.

3. Avoid cooking food on wood stoves and using candles to reduce indoor smoke.

4. Keep a check on Air Quality Index (AQI) of the surroundings and avoid going outside if the levels are very bad.

Air Quality Index (AQI)

Air Quality Index is a number that indicates the air quality of a given spot. AQI is classified into six levels, which are colour coded to help understand how it can affect our health.

AQI	Remark	Color Code	Possible Health Impacts
0-50	Good		Minimal impact
51-100	Satisfactory		Minor breathing discomfort to sensitive people
101-200	Moderate		Breathing discomfort to the people with lungs, asthma and heart diseases
201-300	Poor		Breathing discomfort to most people on prolonged exposure
301-400	Very Poor		Respiratory illness on prolonged exposure
401-500	Severe		Affects healthy people and seriously impacts those with existing diseases