What are PM 2.5 and PM 10 – Sources, Standards and Their Impact on Health?

You must have come across news reports and TV debates talking about alarming levels of air pollution and poor air quality. All these news reports and TV debates always mention a numerical number, called ‘AQI (Air Quality Index)’. AQI is nothing but a measure of how polluted the air is.

The Air Quality Index considers 8 pollutants – PM 10, PM 2.5, Nitrogen Dioxide – NO2, Sulfur Dioxide – SO2, Carbon Monoxide – CO, Trioxygen – O3, Azane – NH3, and Lead – Pb.

Out of all these 8 pollutants, you must be aware of or have read about some of these during your school or college days. But what most people are not aware of or have no idea about, are PM 2.5 and PM 10.

Air pollution is the 3rd leading risk factor for mortality, accounting for almost 13% of deaths (1.2 million) in India in 2017 alone.

Read the following post to understand what are PM 2.5 and PM 10, their sources and health effects.

What is Particulate Matter?

Particulate matter or PM, which is also known as particle pollution, is a mix of solid particles as well as liquid droplets that are present in the atmosphere. These particles are so small in size that they cannot be seen with naked eyes, these particles can be so small that they can only be viewed with a microscope.

Particle pollution consists of two matters that are known as PM 2.5 and PM 10, which are considered to be very dangerous for human health. Particulate matter is a mixture of sophisticated materials like smoke, soot, nitrates, metals, dust, water, sulphates, rubber, and more.

The 10 countries with the highest mortality burden attributable to air pollution in 2017 were China (1.2 million), India (1.2 million), Pakistan (128,000), Indonesia (124,000), Bangladesh (123,000), Nigeria (114,000), the United States (108,000), Russia (99,000), Brazil (66,000), and the Philippines (64,000).

What are PM 2.5 and PM 10?

PM 2.5 is indicative of the atmospheric particulate matter that has a diameter of less than 2.5 micrometers. A rough idea of how small 2.5 micrometers can be is that these particles are as small as about 3% of the diameter of a human hair. These particles are hence so small that these particles can only be detected under an electron microscope.

PM 2.5 is generally associated with vehicular emissions, burning of waste, and industrial combustion processes.

On the other hand, PM 10 particles are those particles with a diameter of about 10 micrometers or less, and hence, they are also very fine particles undetected by the naked human eye. These particulate matters spread more due to pollution and due to dust, construction work, and the burning of wastes.

Sources of PM 2.5 and PM 10 Pollution

Particulate matter can be of varied shapes and sizes and can emerge from both natural as well as man-made sources. These sources can be termed as primary and secondary sources.

The primary sources include sources like automobile emissions, cooking smoke, and dust.

A recent analysis by Health Effects Institute (HEI) found that major PM2.5 sources in India include household burning of solid fuels; dust from construction, roads, and other activities; industrial and power plant burning of coal; brick production; transportation; and diesel-powered equipment.

The secondary sources are those sources of pollutants that are due to complex chemical reactions like nitrogen oxide and sulphur dioxide. These two particles are mixed in the air and are the prime reason for air pollution.

Besides these, other sources also include forest fires, agricultural burning, wood-burning stoves, smoke from the industry, as well as dust from construction sites all around us.

In India, household burning of biomass was responsible for about 24% of the total population-weighted PM2.5 concentrations in 2015. India reduced its proportion of households cooking with solid fuels from 76% in 2005 to 60% (846 million) in 2017 due in part to a major government program to shift households from solid fuels to liquefied petroleum gas. The government initiative, known as Pradhan Mantri Ujjwala Yojana (PMUY), provided LPG connections to 35 million poor families free of charge between 2016 and early 2018 and aims to provide 80 million connections by 2020.

Air Quality Standards for PM 2.5 and PM 10 Pollution

The standard or optimum amount of PM 2.5 or PM 10 that should be in the air has been standardized by many countries.

Notified on 18 November 2009, the National Ambient Air Quality Standards are the standards for ambient air quality set by the Central Pollution Control Board.

An estimated 846 million people in India (60% of the population) were exposed to household air pollution in 2017.

As per the standards, the average level of PM 10 that should be present in the air without being harmful is 100 micrograms cubic meter. On the other hand, the appropriate amount of PM 2.5 that should be in the air is 60 micrograms cubic meter.

The amount of PM 2.5 and PM 10, however, is increasing at an incredibly high rate, which is leading to harmful levels of air pollution. This is leading to a high risk of damage to human health, and hence, precautions have to be taken.

AQI Category (Range)	PM10 (24hr)	PM2.5 (24hr)
Good (0-50)	0-50	0-30
Satisfactory (51-100)	51-100	31-60
Moderately polluted (101-200)	101-250	61-90
Poor (201-300)	251-350	91-120
Very poor (301-400)	351-430	121-250
Severe (401-500)	430+	250+

Health Impact of PM 2.5 and PM 10 Pollution

Because of the small size of particulate matter, they may be considered as gases in general. When you breathe through the air that has such components, they penetrate into your lungs and can cause an asthma attack as well as other respiratory problems.

Breathing in air that is so polluted can lead to heart attacks, blood pressure, diabetes, and even stroke that may lead to premature death. In fact, with high levels of PM 2.5 in the air, the chances of mist and fog increase, which affects visibility to a great extent and may lead to an increased number of accidents.

As per the State of Global Air report, PM 2.5 pollution contributed to nearly 3 million deaths, or 5.2% of all global deaths in 2017. In 2017, PM 2.5 pollution resulted in around 673,100 deaths in India alone.

These suspended particles have the worst effect on children and old age people, mainly because of low immunity. Some other health-related problems that can take place when you are exposed to these particulate matters are as follows:

• Respiratory problems.
• Irritation in the eyes, nose, and throat.
• Tightness in the chest area.
• Impairment of the lungs.
• Problem in breathing.
• Irregular heartbeat.
• Skin related complications.

AQI	Associated Health Impacts
Good (0-50)	Minimal impact
Satisfactory (51-100)	May cause minor breathing discomfort to sensitive people.
Moderately polluted (101-200)	May cause breathing discomfort to people with lung disease such as asthma, and discomfort to people with heart disease, children and older adults.
Poor (201-300)	May cause breathing discomfort to people on prolonged exposure, and discomfort to people with heart disease.
Very poor (301-400)	May cause respiratory illness to the people on prolonged exposure. The effect may be more pronounced in people with lung and heart diseases.
Severe (401-500)	May cause respiratory impact even on healthy people, and serious health impacts on people with lung/heart disease. The health impacts may be experienced even during light physical activity.

What Should You Do if PM 2.5 and PM 10 Levels are High?

• Stay indoors.
• Try to keep your activity levels low, avoid activities that make you breathe faster or more deeply.
• Avoid using anything that burns, such as wood, incense sticks, and even candles.
• Avoid dusting, you can use a vacuum cleaner (with HEPA filter) or clean using a wet cloth.
• Don’t smoke.
• Use an electric air purifier at your home and office to keep the indoor air clean.
• When the outdoor air quality improves, open the doors and windows for proper ventilation.
• Wear an anti-pollution mask when you go outside.
• Plant air purifying plants.
• Stay away from construction sites.

What Can You Do to Lower PM 2.5 and PM 10 Pollution?

• Stop smoking.
• Try to avoid any construction work when the air quality is not good.
• Burning waste, leaves, wood, agricultural waste or anything else should be strictly prohibited.
• Old diesel vehicles should be replaced with newer vehicles, if possible with those using clean fuels like CNG or electric-powered vehicles.
• Construction material should not be kept out in the open or left uncovered.
• Identify sites that act as a source of dust. Such sites should either be turned in to green areas or the land should be covered with a layer of concrete.
• Roads should be cleaned using sophisticated vacuum machines.
• Industrial activities that lead to air pollution should be strictly prohibited when the Air Quality Index is high.

Conclusion

The only way you can fight the effects of PM 2.5 and PM 10 in the environment is with the help of taking appropriate measures to curb this effect. The best way to help yourself is by wearing masks regularly and also consulting doctors when the problem becomes severe.

Make sure to limit your outdoor activities if the pollution level is too high. Burning wood and trash are the major sources of particulate matter, and hence burning these should be totally prohibited.

Smoking, both indoors as well as outside, should also be controlled.

You can protect yourself and your family from the harmful effects of indoor air pollution by using an electric air purifier.

Sources:

• National Air Quality Index (Arthapedia) – http://www.arthapedia.in/index.php?title=National_Air_Quality_Index
• State of Global Air Report – https://www.stateofglobalair.org/sites/default/files/soga_2019_report.pdf