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Satna and in Urban-Industrial South Delhi. Kaushik K. Shandilya & Mukesh Khare & Akhilendra Bhushan Gupta. Received: 18 March 2006 /Accepted: 14 June ...
Environ Monit Assess (2007) 128:431–445 DOI 10.1007/s10661-006-9337-z

Suspended Particulate Matter Distribution in Rural-Industrial Satna and in Urban-Industrial South Delhi Kaushik K. Shandilya & Mukesh Khare & Akhilendra Bhushan Gupta

Received: 18 March 2006 / Accepted: 14 June 2006 / Published online: 10 October 2006 # Springer Science + Business Media B.V. 2006

Abstract An air quality sampling program was designed and implemented to collect the baseline concentrations of respirable suspended particulates (RSP = PM10), non-respirable suspended particulates (NRSP) and fine suspended particulates (FSP = PM2.5). Over a three-week period, a 24-h average concentrations were calculated from the samples collected at an industrial site in Southern Delhi and compared to datasets collected in Satna by Envirotech Limited, Okhla, Delhi in order to establish the characteristic difference in emission patterns. PM2.5, PM10, and total suspended particulates (TSP) concentrations at Satna were 20.5 ± 6.0, 102.1 ± 41.1, and 387.6 ± 222.4 μg m−3 and at Delhi were 126.7 ± 28.6, 268.6 ± 39.1, and 687.7 ± 117.4 μg m−3. Values at

K. K. Shandilya Civil and Environmental Engineering Department, Clarkson University, Potsdam, NY, USA M. Khare (*) Atlantic LNG Chair (Professor) in Environmental Engineering, University of West Indies, St. Augustine Campus, St. Agustine, Trinidad and Tobago e-mail: [email protected] A. B. Gupta Civil Engineering Department, Malaviya National Institute of Technology, Jaipur, India

Delhi were well above the standard limit for 24-h PM2.5 United States National Ambient Air Quality Standards (USNAAQS; 65 μg m−3), while values at Satna were under the standard limit. Results were compared with various worldwide studies. These comparisons suggest an immediate need for the promulgation of new PM2.5 standards. The position of PM10 in Delhi is drastic and needs an immediate attention. PM10 levels at Delhi were also well above the standard limit for 24-h PM10 National Ambient Air Quality Standards (NAAQS; 150 μg m−3), while levels at Satna remained under the standard limit. PM2.5/PM10 values were also calculated to determine PM2.5 contribution. At Satna, PM2.5 contribution to PM10 was only 20% compared to 47% in Delhi. TSP values at Delhi were well above, while TSP values at Satna were under, the standard limit for 24-h TSP NAAQS (500 μg m−3). At Satna, the PM10 contribution to TSP was only 26% compared to 39% in Delhi. The correlation between PM10, PM2.5, and TSP were also calculated in order to gain an insight to their sources. Both in Satna and in Delhi, none of the sources was dominant a varied pattern of emissions was obtained, showing the presence of heterogeneous emission density and that nonrespirable suspended particulate (NRSP) formed the greatest part of the particulate load. Keywords Ambient air quality . SPM . Urban and rural industrial pollution . Emission pattern

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1 Introduction An association between high levels of ambient particles and human mortality has been well established. Besides this, three major effects of suspended particulate matter (SPM) are acid deposition (Sequeira, 1982); changes in visibility (Toon, Pollack, & Sagan, 1977), and ozone (Papayannis et al., 1998). For this reason, SPM in the air has been considered the world over as the most significant criteria to indicate air quality. In recent decades, the emission of TSP and the ambient levels of TSP have fallen substantially due to the implementation of air pollution control devices (e.g., filters, electrostatic precipitators, etc.). Thereafter, it was expected that these measures would prevent further human health effects associated with particles. Since the late 1980s, however, epidemiological studies published relating mortality and morbidity to ambient levels of fine particles (Thurston, Ito, Lippmann, & Hayes, 1989; Thurston, Ito, Hayes, Bates, & Lippmann, 1994; Dockery & Schwartz, 1995) do not show the expected results. Fine particles due to high diffusion coefficients have a very high probability of deposition deep in the respiratory tract and cause a variety of health effects in human beings. Most emphasis was then given to particles with an aerodynamic diameter smaller than 10 μm (PM10) – the class of fine particulates. A special study carried out by United Nations Sources (WHO, 1979) shows that the frequency of finding a particle of diameter range 2–4 μm is 27.5%, and is higher in the range of 1–12 μm; so the danger of fine particulates of diameter range 2–4 μm is higher than the danger for any other particles which may lie in the range of 4–12 μm. The conversion of gaseous matter into particulates known as “Secondary Aerosols” (Buch, 1972) is due to many physicochemical reactions. As a result, there is currently a rising awareness about secondary aerosols with still finer fraction, i.e., particles with an aerodynamic diameter smaller than 2.5 μm (PM2.5). The major manmade sources of atmospheric aerosols are industrial processes, transportation, power generation, space heating, and refuse incineration (Peavy, Rowe, & Tchobanoglous, 1985). In general, for PM2.5 the secondary formation is more relevant than primary emissions, but Wilson and Suh (1997) stated that some natural particles also occur in the size range