How to combat air pollution?

Fourteen of the world’s fifteen most polluted cities are in India, according to the World Health Organization’s report earlier this year. While China has recently unveiled the world’s largest air-purifier tower, we are yet to make any systemic changes in our country. So what can you, as an individual, do to combat air pollution? We get experts to help you.

IFL Kuwait

“Even if you have air purifiers inside your home, once you step outside into the traffic, you are back to square one,” says Dr Salvi. Enter, face masks. “The N95 face masks are the ones that are the most recommended in terms of efficiency; they filter out 95% of PM 2.5,” he says. The other less expensive options are the surgical masks. Made of cloth, “they are more comfortable but filter out only 40-50% of pollutants,” he explains, adding that they are good enough for moderate levels of pollution, and should be worn immaterial of whether you have any lung disease or not.

Apart from the medical factors, the plain visual impact of masks should be a reason enough, according to Reecha Upadhyay, Campaigns Director of HelpDelhiBreathe. “Look at Bangkok, look at Beijing and Shanghai, when you see so many people wearing masks, it underlines the need for lowering the pollution,” she says. The more noise you make, the more you take your own health seriously, the faster the Government wakes up to the problem.

The fine print

You can only wear the N95 and N99 masks for a few hours, says Dr Salvi, pointing out that they are not very comfortable. “Breathing becomes more difficult,” he says. “The mask isn’t fool-proof either,” says Dr Guleria. “Depending on their fitting, some masks may have space on the side through which air can be sucked in when you breathe.”

Air purifiers

Do I need one?

It all depends on what grade of air purifier you are using, says Dr Salvi. “You need ones that filter out PM 2.5, because by and large, they cause more harm than your gaseous pollutants like ozone.” There is research from China to suggest that control of asthma may be better if you use good-quality HEPA (high-efficiency particulate air) filters, adds Dr Guleria. He adds though that there is no hard data saying it completely prevents asthma attacks. People who generally stay indoors and have asthma or chronic obstructive pulmonary disease (COPD), will benefit the most from using an air purifier inside the house, while the pollution levels are dangerously high, concludes Dr Salvi. Even if it brings down the pollution from the very poor category to poor, it’s still a step in the right direction.

Air purifiers are used inside rooms, but none of our houses are constructed in a seal-proof manner, explains Dr Guleria. “Even if you do have an air purifier in your room, there is always air coming in from the windows or doorways, which reduces the efficacy.” Ultimately, People use it because they have no option. Low-grade air purifiers do more harm than good, as they release ozone, a pollutant, into the atmosphere. Even if you use a HEPA filter (and they are expensive, starting from ₹20,000), you’re not going to be at home all day and nightwon’t remain inside the house all the time. So in the long run, it is a question of attacking the source of pollution.

Other solutions

Eat right

IFL Kuwait

Take care of your lungs with proper nutrition. Pollution causes free-radical damage, and your body needs to produce a lot of antioxidants to combat them. “To enrich this protective barrier, you need to eat fruits and vegetables rich in antioxidants,” says Dr Salvi, adding, “You also need to drink lots of water. Keep your airways moist; a dry lung absorbs more pollution,” he says.

Clean green

“Studies show that the more green cover in an area, the less the pollution,” says Dr Guleria. “Indoor plants also help, depending in the air quality level and the size of the room,” he says. Try aloe vera, snake plant (commonly known as mother-in-law’s tongue), spider plant, and bamboo palm.

Munch on jaggery

It’s traditionally eaten in places where there are high levels of particulate matter, such as in the deserts of Rajasthan and in industries, says Manjari Chandra, a Delhi based dietician. “It works in three ways: it is rich in iron, so enriches the blood with haemoglobin. The blood then carries oxygen better. It’s rich in minerals such as zinc, selenium, potassium and phosphorus, that have an antiallergy effect by strengthening respiratory channels and boosting immunity,” she says.

New technologies

NasoFilter: Strap it on to your nostrils. Its creator, Prateek Sharma, an IIT-Kanpur graduate, says the nano-filters prevent 90% particulate matter from entering the nose. Priced at Rs 10 each, one strip lasts one day.

Dyson makes air purifier fans that also sense and display the air quality levels.

But what is AQI?

We get Prashant Gargava, Member Secretary, Central Pollution Control Board, Delhi, to explain what those numbers mean.

Simply put, AQI -- the Air Quality Index -- is a way to communicate the air pollution levels in an easy way. It is one number that can fall into six colour-coded categories that determine what the health impact would be: 0 to 50 is good, 51 to 100 is satisfactory, 100 to 200 is moderate, 200 to 300 is poor, 300 to 400 is very poor.

How is it calculated?

The CPCB has monitors across cities that continuously measure the levels of eight pollutants -- PM2.5, PM10, SO2, NO2, Ozone, Lead, Ammonia, and CO -- drawing up a running average every hour. It is essential that a minimum of three parameters are monitored, out of which one of them has to be Particulate Matter.

Depending on how unhealthy it is, each pollutant has its own indice (or weight) and is given an AQI value. The worst of these eight AQI values is taken as the AQI value of the area.

AQI is very location specific. Across a city, different places will have different AQIs.