Toxic Delhi air can get deep into your lungs; 22 million at risk

Pollutant particles can cross the blood-brain barrier and cause permanent harm to cognitive development

By Anisha Raman
Published: Friday 04 November 2016
About 22 million residents in Delhi-NCR are currently breathing severely toxic air. Credit: Adam Jones / Flicker
About 22 million residents in Delhi-NCR are currently breathing severely toxic air. Credit: Adam Jones / Flicker About 22 million residents in Delhi-NCR are currently breathing severely toxic air. Credit: Adam Jones / Flicker

Every year, Delhi witnesses high pollution level in ambient environment during Diwali. The papers are inundated with numerous reports citing statistics from DPCC, CPCB and other sources. To the lay man, the message is lost between these numbers.

This year, Delhi-based nonprofit, the Centre for Science and Environment, with Aaj Tak, conducted exposure monitoring of the Delhi air during the Diwali Night. The exposure monitoring conducted at two locations—R K Puram and Chattarpur—gives us an indicator of what an ordinary human breathes. Unlike the monitoring done at DPCC and CPCB stations (at a much higher height), this was done at the average human height. The monitoring provided us with an indicative level of real-time exposure to pollutants of a Delhi citizen. The average standard of PM2.5 in a day is 60µ/m3 and average standard for PM 10 in a given day should not be more than 100µ/m3.

The CSE has also tracked the real-time air pollution data reported in the official website of the Delhi Pollution Control Committee on the night of Diwali. Calm weather with nearly no wind blocked quick dispersal of smoke and pollutants. The crackers are burst the highest in residential areas. Such high level of exposure can lead to escalation in hospital admissions related to respiratory and cardiac symptoms.

The monitoring was conducted on Sunday evening in R K Puram a predominantly residential area, housing several schools and institutions. The results showed that PM 2.5 concentration in the air was at 310µ/m3, occasionally attaining a peak of 411 µ/m3. It was being directly inhaled at the ground level. The PM 10 levels were averaging at 377µ/m3, reaching a peak of 1110 µ/m3.

Meanwhile, in the high density area of Chattarpur, PM 2.5 concentration at night was initially 872 µ/m3, touching a maximum of 1270 µ/m3. The PM 10 readings averaged at 1400µ/m3, reaching 2060 µ/m3. Chattarpur was monitored on October 31 as a follow-up exercise. The PM 2.5 concentration level averaging at 551µ/m3 reached 629µ/m3. The PM 10 readings showed an average of 784µ/m3 with a maximum of 1170µ/m3.

It means that the air a resident inhaled at R K Puram was five times more polluted than the standard. At Chattarpur, the air was 15 times more polluted than the standard. The CPCB has set the severe category for PM 2.5 concentrations at 250µ/m3. This means that the air we were breathing was four times more dangerous than the air that CPCB categorizes as ‘severe’.

What does Delhi air do to your health?

Now, at 90-120µ/m3 PM 2.5 concentration level, people with respiratory issues start feeling the strain of the polluted air and at 120-250µ/m3, which is categorised as “very poor”, the risk of developing respiratory illness on prolonged exposure increases. Even a healthy person with prolonged exposure to air of ‘severe’ category will start experiencing breathlessness, wheezing and chest constrictions.

The DPCC data shows PM 2.5 levels ranged between 180µ/m3 and 440µ/m3compared to 184-369 µ/m3 in 2015. Thus, maximum levels have remained more than seven times the standards and worse than last year overall. The DPCC data for the week preceding Diwali shows that the mass concentration in Delhi air on October 29-30 had increased by 45 per cent. The day time to night time air pollution increased by 3.2 times. The night time pollution during Diwali was in the severe category.

About 22 million residents in Delhi-NCR are currently breathing severely toxic air. UNICEF report released on the day after Diwali states that around 600,000 children under the age of five die from diseases linked to indoor and outdoor air pollution. The number of child deaths is more than the casualties caused by malaria and HIV/AIDS combined. Children are far more vulnerable to air pollution because they breathe more rapidly than adults. The cell layer in their lungs is also more permeable to pollutant particles that can cross the blood-brain barrier and cause permanent harm to cognitive development. Air pollution also affects the unborn as the particles inhaled by pregnant mothers can cross the placental barrier (also known as “leakiest barrier”), thus injuring fetuses.

Over three million people a year (six people every minute) die due to outdoor air pollution. It is likely to double by 2050.

Inertia on the part of the government

The Delhi government, despite being aware of the severe air pollution levels, did nothing to ban the firecracker from the city, rather choosing to focus their efforts on Chinese crackers, oblivious to the harm caused by the desi crackers. Delhi, as was predicted, choked on toxic smog the following day. The SAFAR forecast predicted poor AQI and issued a public health warning to “stay indoors”. This comes with no directives to shut down schools, institutions and industrial activity in the city.

In 2015, Beijing issued its first ever red alert, health advisories with emergency action plan when the city faced three consecutive days of smog. Schools were shut, outdoor construction was halted and restriction on car use and certain factories within the city limits was imposed.

The smog on November 2 was a harrowing experience for the people of Delhi, with the outdoor environment looking eerily similar to Beijing’s ‘airpocalypse’. Considering the mass migration of pollutants from farm fires in Punjab and Haryana to Delhi, it’s time the government took aggressive action to curb emission from combustion sources and fugitive sources. Public health advisories with directives should be issued. Efforts should be made to build hard evidence of air pollution’s impact on Delhi’s population. General hospitals, especially children’s hospitals, should be monitored for cases and admissions. Health information, thus created, would enable strategic action for combating winter pollution.

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