Delhi’s air is not polluted as much with poisonous gases as it’s with really tiny particles known as PM2.5. And its levels are consistently 16-20 times higher than the prescribed standard. At the time of the Delhi half marathon, it was 48 times the limit.
Greenpeace recently found that even inside Delhi’s classrooms, PM2.5 levels were 11 times the limit.
PM2.5 at a glance:
- PM stands for particulate matter, while the number refers to the size of the particles. So, PM2.5 is like extremely fine dust whose particles are just 2.5 microns wide — that’s thirty times smaller than the width of a human hair.
- The tiny size makes it harder to prevent PM2.5 from getting into the body, making it deadlier.
- Particulate matter, or PM, is the term for particles found in the air, including dust, dirt, soot, smoke, and liquid droplets. Particles can be suspended in the air for long periods of time. Some particles are large or dark enough to be seen as soot or smoke. Others are so small that individually they can only be detected with an electron microscope.
- Many man made and natural sources emit PM directly or emit other pollutants that react in the atmosphere to form PM. These solid and liquid particles come in a wide range of sizes.
- Sources of fine particles include all types of combustion activities (motor vehicles, power plants, wood burning, etc.) and certain industrial processes.
- Particles with diameters between 2.5 and 10 micrometers are referred to as “coarse.” Sources of coarse particles include crushing or grinding operations, and dust from paved or unpaved roads.
- Other particles may be formed in the air from the chemical change of gases. They are indirectly formed when gases from burning fuels react with sunlight and water vapor. These can result from fuel combustion in motor vehicles, at power plants, and in other industrial processes.
- The group at higher risk of experiencing PM2.5 related health effects is active children because they often spend a lot of time playing outdoors and their bodies are still developing.
- In addition, oftentimes the elderly population are at risk. People of all ages who are active outdoors are at increased risk because, during physical activity, PM2.5 penetrates deeper into the parts of the lungs that are more vulnerable to injury.
- Being tiny, these particles easily reach the lungs. From there, they can travel through the bloodstream and reach the heart.
- Long exposure to PM2.5 can worsen asthma and heart conditions. They also cause runny nose, sneezing and coughing.
- PM2.5 coming from diesel vehicles contains carbon and is a carcinogenic.
- It can also cause other heart and lung diseases, or make them worse.
- It slows down development of lungs in children and can leave them with reduced lung function for the rest of their lives, according to the WHO.
- Illnesses caused by PM2.5 kill at least 3.1 million people a year across the world.
- The WHO estimates that exposure to PM2.5 reduces a person’s life expectancy by an average of 8.6 months.
The government has largely failed to make people aware of how the pollution affects them, what the main pollutants are, what precautions they should take, the types of masks they should wear, and suchlike. There is no air warning system in Delhi that could alert citizens, shut down schools and prohibit outdoor activity when pollution reaches hazardous levels.
Protecting yourself from PM2.5 doesn’t require gas masks, but cotton masks that can block very fine particles. It is recommended to use an N-95 mask, the same one used to protect against the H1N1 virus. Unfortunately, planting more trees does nothing to solve the problem. Since PM2.5 are particles and not gases, they can’t be processed by the leaves. The only way to cut down PM2.5 levels is to stop it at the source – cars, factories, waste burning, thermal power plants.