Kanpur is the most polluted among the major cities
in terms of air quality with a very high presence of Respirable
Suspended Particulate Matter (RSPM) while Chennai is the least
polluted. Fine Particulate Matter present in the air enter into
the lungs and cause inflammation worsening the condition of the
people with heart and lung diseases. For the period January to
April, 2002, as per the data collected by the Central Pollution
Control Board (CPCB), RSPM levels varied from 119 – 257 micrograms
per cubic meter while it was in the range of 25 – 49 micrograms
per cubic meter in case of Chennai.as against the standard level
of 60 micrograms per cubic meter. RSPM levels for the said period
for Delhi 119-257, Kolkatta 55-129, Bangalore 65-119 and Vadodara
84-119 micrograms per cubic meter.
The air quality data indicate that in most
of the metropolitan cities, the suspended particulate matters
levels have exceeded the National Ambient Air Quality Standard
(NAAQS) while sulpher dioxide and nitrogen oxide remained within
the NAAQS limit of 60 micrograms per cubic meter. Action Plans
have been formulated for mega cities such as Delhi, Mumbai, Chennai
and Kolkatta. Delhi has shown a decreasing trend of air pollution
after the implementation of the Action Plan to contain pollution.
Action Plans for Kanpur and other critically polluted towns/cities
are under implementation. The Central Pollution Control Board
in consultation with the State Boards has identified 24 such critically
polluted areas. A total of 152 large and medium polluting industries
are located in these areas out of which 17 were closed and all
the remaining industries have installed the requisite pollution
control facilities.
In respect of sulpher dioxide and nitrogen
oxide levels in the air also, Chennai is the least polluted with
these levels remaining low at 4 micrograms per cubic meter and
10 –13 micrograms per cubic meter respectively. These pollutants
irritate the airway of the lungs increasing the symptoms of those
suffering from lung diseases.
CPCB monitors air quality through a network
of 295 stations covering 96 towns/cities. The pollutants monitored
are sulpher dioxide, nitrogen dioxide and suspended particulate
matter. The main source of air pollution include the vehicular,
industrial, domestic and other sources. There are seven mega cities
with a population of more than 40 lakhs each and 28 metro cities
with a population of more than 10 lacks each in the country.
The measures taken to control air pollution
include introduction of cleaner fuels, stricter emission standards,
banning the use of vehicles of specified ages etc. Unleaded petrol
is being supplied throughout the country from 1.2.2000 and diesel
with 0.25 per cent sulpher from 1.1.2000. Ultra low sulpher (0.05%)
petrol and diesel has also been introduced in major cities. CNG
is being used a fuel in Delhi and Mumbai. Euro-II emission norms
for both private and commercial vehicles were made effective in
National Capital Region of Delhi, Mumbai, Kolkatta and Chennai
while Euro-I norms for four-wheeled private vehicles were made
applicable in the remaining parts of the country.
