City's average air quality down, Chanda 'shocking' 22; experts question data

Nagpur: The state’s worst air quality during this year’s Diwali was recorded in Kalyan on the second day of the festival. Overall, most parts of the state saw significantly cleaner festive days compared to previous years, reveals data released by the Maharashtra Pollution Control Board (MPCB).

Though they agree with “lesser pollution”, experts have raised doubts over accuracy of the board’s data.

Air quality index (AQI) of all ten monitored cities – Aurangabad, Chandrapur, Kalyan, Mumbai, Nashik, Navi Mumbai, Pune, Solapur, Thane and Nagpur remained under good, satisfactory and moderate levels during the festive period. AQI is a tool which measures the ambient concentrations of pollutants and transforms complex data into a single number.

To assess the impact of firecracker bursting on the ambient air quality, the board monitored air for three days during Diwali. Its recently released ‘AQI Bulletin for Diwali festival monitoring 2019’ shows that on the day of Laxmi Puja, Solapur recorded the worst AQI at 115, which comes under moderate category and can cause breathing discomfort to people with lungs, asthma and heart diseases. The prominent pollutant in the city that day was carbon monoxide, a dangerous toxin emitted from burning of fireworks.

Last year, Nagpur had the worst air during Laxmi puja with an average AQI of 135. This year, the city’s average AQI came down to 64, which is ‘satisfactory’ as per the standards set by the Central Pollution Control Board (CPCB). This Diwali, Chandrapur recorded an AQI of just 22 as per the board’s bulletin, which categorizes its air quality as ‘good’.

Though experts agree that the pollution was less this time, they brushed aside the board’s figures which are “unrealistically low”. Suresh Chopane, founder of Chandrapur-based Green Planet Society said, “It is true that the quantity if crackers was comparatively low this time, with people busting them only on the day of Laxmi puja rather than on all five days. However, it is impossible that the average AQI would be 22 on Laxmi puja as the real-time hourly figures showed levels of PM2.5 going as high as 466.”

Rather than releasing the lowest recordings, Chopane said that the board should reveal the highest levels of AQI and particulate matter to present the real picture.

As per board officials, rainfall in many parts of the state resulted in less pollution during Diwali as rains suppressed the pollutants present in ambient air.

Stating that apart from climatic conditions, founder of Green Vigil Foundation Kaustav Chatterjee said that high cost of crackers and, imbalance in demand and supply chain also contributed towards better air quality. “Most importantly, AQI levels of almost all cities barring metros are based on data from one or two monitoring stations, which doesn’t provide accurate picture of the city’s air quality,” added Chatterjee.

State AQI Bulletin during Diwali

City--------- 2019 Diwali Day 1----2018 Diwali Day 1----2019 Bhai Dooj------2018 Bhai Dooj——-2019 Diwali Day 2

Aurangabad--- S (64) --------————- NA---------------S (62)-------——-M (183)———————— S (69)

Chandrapur—G (22)—————S (90)—————-S (84)———M (142)———————————M (139)

Kalyan——S (88)———- NA——————-M (148)————NA————————————- M (174)

Mumbai——S (92)——— M (127)————- M (112)——— M (183)——————————— M (104)

Nashik——G (33)——————-NA———— G (31)————M (142)———————————- S (73)

Navi Mumbai—S (85)—— M (106)—————S (94)———M (101)————————————M (133)

Pune ———-S (82)——— M (104)—————-S (99)———M (141)————————————M (148)

Solapur——M (115)————S (78)—————S (85)——M (125)——————————————S (96)

Thane——-S (55)————NA—————— S (78)————NA——————————————-S (96)

Nagpur——S (64)————-M (135)————M (140)———M (134)—————————————S (73)

Note:

S - Satisfactory

M - Moderate

NA- Not Available

2018 data for 2nd day of Diwali not available