6.2   STATUS OF RESPIRABLE PARTICULATE MATTER  

RSPM levels were measured in various cities and towns in India. The RSPM levels in residential areas during 2000 are depicted in Fig 6.5. RSPM levels exceeded the NAAQS (annual average) in residential areas of Hyderabad, Visakhapatnam, Delhi, Ahmedabad, Parwanoo, Bangalore, Cochin, Dehradun, Thiruvananthapuram, Mumbai, Nagpur, Pune, Solapur, Angul, Rourkela, Jaipur, Chennai, Kanpur, Lucknow and Kolkata. The RSPM levels in industrial areas during 2000 are depicted in Fig 6.6. RSPM levels also exceeded the NAAQS (annual average) in industrial areas of Ahmedabad, Dehradun, Thiruvannathapuram, Solapur, Jaipur, Kanpur and Kolkata.

RSPM levels were within the NAAQS (annual average) in residential areas of Kozhikode and Shillong and industrial areas of Hyderabad, Visakhapatnam, Bangalore, Mysore, Cochin, Kotayam, Kozhokode, Palakkad, Mumbai, Nagpur, Pune, Rourkela and Chennai.

Non-attainment Areas

Air quality with reference to RSPM is expressed in terms of low, moderate, high and critical. Critical levels of RSPM were observed in residential areas of Hyderabad, Delhi, Ahmedabad, Bangalore, Cochin, Dehradun, Thiruvananthapuram, Mumbai, Nagpur, Pune, Solapur, Rourkela, Jaipur, Kanpur, Lucknow and Kolkata. High levels of RSPM were observed in residential areas of Visakhapatnam. Parwanoo, Angul and Chennai. These results indicate that NAAQS (annual average) of RSPM was exceeded in above cities.

Critical levels of RSPM were observed in industrial areas of Ahmedabad, Thiruvananthapuram, Solapur, Jaipur, Kanpur and Kolkata and high levels of RSPM were observed in industrial areas of Hyderabad and Dehradun during year 2000. These results indicate that NAAQS (annual average) of RSPM was exceeded in above mentioned cities. Moderate levels were observed in residential areas of Kozhikode & Shillong and industrial areas of Mysore, Cochin, Kottayam, Mumbai, Nagpur, Pune and Rourkela. These results indicate that NAAQS (annual average) was not exceeded in above mentioned cities. The number of cities with critical, high and moderate RSPM levels in residential area and industrial area are presented in Fig 6.7 and 6.8 respectively. RSPM status of various cities is depicted in Table 6.3.

Note :  ‘-‘ - Data Not Available/Inadequate

* - Representing one monitoring station in residential area

6.3       AIR QUALITY TREND AND NON-ATTAINMENT AREAS

The analysis of ambient air quality data obtained during different years from 1995 onwards was carried out. The concentration ranges for different levels have been selected based on the Notified Standards for different pollutants and area classes by calculating an Excedence Factor (the ratio of annual mean concentration of a pollutant with that of a respective standard). The Excedence Factor (EF) is calculated as follows:                                 

Excedence Factor =  Observed annual mean concentration of a criterion pollutant  
                                Annual standard for the respective pollutant and area class

The four air quality categories are:

·Critical pollution (C): when  EF is more than 1.5;

·High pollution (H): when  EF is between 1.0 - 1.5;

·Moderate pollution (M): when EF is between 0.5 - 1.0; and

·Low pollution (L): when EF is less than 0.5.

Number of cities falling under different categories were plotted against years. It is observed that there is a increasing trend in number of cities with moderate levels of NO₂ and decreasing trend in number of cities with high levels of NO₂. This is probably due to number of cities shifted from high to moderate levels. It is also observed that cities with low and moderate levels of pollution are more than the cities with High levels.

6.4       AIR QUALITY STATUS IN MAJOR CITIES

Central Pollution Control Board initiated National Ambient Air Quality Monitoring (NAAQM) programme in the year 1984 with 7 stations at Agra and Anpara. Subsequently in 1998-99 the programme was renamed as National Air Monitoring Programme (N.A.M.P.). The number of monitoring stations under N.A.M.P. has increased, steadily, to 295 by 2000-01 covering 98 cities/towns in 29 States and 3 Union Territories of the country. Under N.A.M.P., four air pollutants viz., Sulphur Dioxide (SO₂), Oxides of Nitrogen as NO₂ and Suspended Particulate Matter (SPM) and Respirable Suspended Particulate Matter (RSPM/PM₁₀), have been identified for regular monitoring at all the locations. The monitoring of pollutants is carried out for 24 hours (4-hourly sampling for gaseous pollutants and 8-hourly sampling for particulate matter) with frequency of twice a week, to have 104 observations in a year.

It has been observed that air pollution problem is serious mainly due to high vehicular population in seven major cities in India namely Ahmedabad, Bangalore, Chennai, Delhi, Hyderabad, Kolkata and Mumbai. An attempt has been made to address the problem of air pollution in these cities. Estimates are made of air pollutants load coming from vehicles. Status of air pollutants are also established to find the air pollutants, that are exceeding the air quality standards.  The air pollutants load from vehicles is depicted in Fig 6.9 and levels of SO₂, NO₂, SPM and RSPM during 2001 is shown in Fig 6.10.  Following are the findings of the analysis carried out.

Ø      Urbanisation in India is more rapid around national capital and state head quarters. Over the years, these cities have become a major center for commerce, industry and education. Increase in population, both endemic and floating, increase in industrial activities, vehicular population etc. have led to a number of environmental problems, one of them being air pollution. Enormous increase in number of vehicles has resulted in increased emission of air pollutants from motor vehicles.

Ø      SO₂, and NO₂ levels are within NAAQS (Annual average) in Ahmedabad, Bangalore, Chennai, Delhi, Hyderabad and Mumbai.


Ø      Short-term violation of NO₂ is observed especially during winter months in Mumbai and Delhi.

Ø      Most critical form of pollution is Respirable Suspended particulate Matter at all the seven cities.

Ø      SPM levels are also exceeding the NAAQS (Annual average) in Ahmedabad, Bangalore, Delhi, Hyderabad, Kolkata and Mumbai in residential areas.

Ø      The reason for high particulate pollution may be vehicular emissions, resuspension of dust, commercial and domestic use of fuel etc. In Ahmedabad emission from power plants and industries located in industrial areas may also contribute to particulate matter pollution. In Mumbai, emission from power plants and oil refinery may also contribute to particulate matter pollution.