As the smog returns to the skyline of Delhi and NCR, the weathermen predict a steep rise in pollution in the coming days. People, already battling the traffic to commute to different parts of the city will have to deal with the poisonous air. While people look out for ways to tackle pollution, words like particulate matter and its variants will be heard and read time and again. Before knowing how do these air contents affect our health and how should we deal with them, let us try to understand what they actually are.
What is a particulate matter?
You’ve probably read the abbreviation, PM. It refers to “particulate matter” and is a term used for the mixture of both solid and liquid particles lingering in the air.
How are they formed?
There are many sources of particulate matter. Some are a result of dust picked by wind, dust flying from construction sites, unpaved sidewalks, open fields and even fire. It can also be a result of gases reacting in the atmosphere such as carbon dioxide, sulphur dioxide, nitrogren oxide and of course pollutants emitted from industries, cars, motorbikes and other vehicles.
What’s the difference between PM 1, PM 2.5, PM 10?
Since particulate matter can be as small as a strand of hair and so often missed by our eyes, others are as big as beach sand – which let’s admit is not that big but in pollution talk, that is considered above average. Safe to say, their different sizes mean they are differently harmful.
PM 10
These are particles whose diameter is less than 10 microns. Uh-oh, what’s a micron now? As hard as this might be to imagine on the scale, a micron is about one millionth of a meter. These are really coarse particles and are usually the result of dust picked up from construction sites and landfills, motor vehicles and industry waste. All PM are harmful, needless to say, but these are less so because they are visible and depending on their size, PM 10 can lodge themselves in your throat and nose.
PM 2.5
These are more harmful than PM 10 because they are smaller and be easily inhaled. Basic rule of thumb in pollution is that the smaller they are, the more harmful they are. PM 2.5 is about 2.5 micrometers large, if not smaller. In order to envision how big that actually is then take a strand of hair to calculate it – a strand of hair is 70 micrometers so go on dissecting that to the tiniest fragment of it possible and you have yourself PM 2.5.
These guys have many sources including fumes from exhausts of motor vehicles, wood and coal burning, forest fires and even cigarette smoke. One cigarette, depending on brand, can release between 7-23 milligrams of PM 2.5, which is a huge number for its size. PM 2.5 can travel deep into your lungs and into the bloodstreams because they are so minute. In the short, they can cause irritation to the eyes and lungs, but in the long term, constant exposure to these small particles can reduce lung function and chronic bronchitis. In fact, the harmful effects of PM 2.5 have been linked to that of smoking cigarettes.
PM 1
Remember that rule of thumb you read about earlier – well, that means these particles, with the same origin of PM 2.5, are the most dangerous pollutants for your health. Particulate matter of size 1 is just so tiny that you could line hundreds of thousands of them in just one sentence on this page.
Another rule of thumb – the smaller the particle, the deeper it travels in your lungs and bloodstream. Even though PM 1 are the most harmful pollutants, national authorities’ data on them is still very much in the first phase.
The Central Pollution Control Board only began monitoring PM 1 in Delhi and other major cities in May 2016.
What does µg/m3 mean?
Air quality data contains numbers and number can be very confusing. More than numbers, it’s the symbols that are scary. You might’ve been intrigued to investigate the air quality in your city, when you so often saw this symbol, µg/m3, and decided to stick to reading the news for air quality information. What this boo-hacky translates to is this - one millionth of a gram per cubic metre.
To put this in context: According to SAFAR’s air quality index, today there are 375 micrograms of PM 10 pollutants per one cubic meter of air, which is equal to one thousand packets of one litre of milk.
In 2013, pollution resulted in the pre-mature deaths of 1.6 million people. Air is inescapable and with every breathing second you spend in Delhi or other major cities in India, you expose yourself to fine and harmful particulate matter that is slowly killing you. It's of utmost urgency and importance that every one of us understands how vicious air in Indian cities is and take preventive actions accordingly.
Now that you know about particulate matter what steps can you take to avoid the ill-effects of particulate matter? That it is not going to be an easy task is understandable. But can you suggest some easy everyday tips or methods that can help us breathe in better air? Share your thoughts in the comments below...