Megacity Ahmedabad that has won awards and recognitions for urban planning is among the top five polluted cities in the country. The 2014 Ambient Air Pollution data base released by the World Health Organisation (WHO) on Thursday showed that the city ranks high in levels of particulate matter (PM) of less than 2.5 microns.
The study measured pollution as the annual mean concentration of fine particulate matter of less than 10 microns of diameter (PM10) [ug/m3 (micrograms per cubic metre)] and of less than 2.5 microns (PM2.5) in various cities.
According to the study, the reason why particulate matter is among those factors measured for air pollution is because these particles are able to penetrate deeply into the respiratory tract and therefore, constitute a risk for health by increasing mortality from respiratory infections and diseases, lung cancer, and other cardiovascular diseases.
Ahmedabad had a PM 2.5 concentration of 100 micrograms making it the fifth most polluted city in the country in that category. The first place went to Delhi that had 153 micrograms of PM 2.5 concentrations, which was the highest among all the 1,600 cities in 91 countries.
Interestingly, Ahmedabad also had the highest level of PM 2.5 concentration among Gujarat cities. The second place was bagged by Jamnagar that had a concentration of 46 microgram. It should be noted that as per the Central Pollution Control Board's Air Ambient Quality Standard, the accepted level of PM 2.5 is 40 micrograms for a year and 60 micrograms for a 24-hour period.
Talking about why the city had high levels of PM2.5 concentration, Mahesh Pandya, an environmentalist, said part of the reason is the heavy construction work for both infrastructure and housing going on in the city.
“These activities increase the level of suspended particulate matter in the air. The second is the high retention of vehicular traffic on the road. Retention refers to the time for which a vehicle stands idle on the road say in traffic jams and such with its engine still running. This has also added to the situation,” said Pandya.
He said BRTS was part of the reason why there were heavy traffic jams in the city resulting in high pollution. “BRTS was supposed to help reduce number of vehicles on road, but what it has done is make the roads narrow leading to more traffic jams and higher retention of vehicles on road,” said Pandya.
The level of PM 10 concentration was 67 micrograms for the city, against the accepted standard of 60 micrograms on a yearly basis and 100 for a 24-hour period. The present study was for data collected for the 2013 period for the city. It should be noted that the air pollution levels were measured for residential and commercial areas and not industrial areas of a given city.
Pandya said the situation could have been countered had we got more green cover. “But Ahmedabad has poor green cover and this has only worsened the situation,” said Pandya.
Rohit Prajapati, another activist, said there was a need for positive discrimination to counter the situation. “We need to make public transport more cheap and accessible, while at the same time making use of private transport more expensive. But right now we are unable to do that because the government has no data on how many private vehicles are there on the city roads,” said Prajapati.
Talking about how suspended particles in the air affect health, consultant pulmonologist, Dr Viral Shah said that such particulate matter can go in the lungs and get deposited there. “It is called chronic obstructive pulmonary disease (COPD) and how early it is diagnosed depends on the extent and severity of the exposure to such particles. It can be made better with treatment but is a non-reversible condition because the particles are indestructible,” said Dr Shah