Atmospheric Pollution Paper Sci & Eng.)

JOURNAL

OF ENVIRON.

SCIENCE &ENGG.

VOL.49,

No.I,P.

22 - 27, January 2007

Atmospheric Pollution: A Case Study of Degrading Urban Air Quality over Punjab, India PARMJIT SINGH SEHRA

This paper presents the results of a case study of urban air quality over a densely populated city Ludhiana situated in Punjab, India, in the form of monthly and annual average concentrations of Suspended Particulate Matter (SPM), N02 and S02 for the periods 1988-1989, 1994-1999 and 2001-2005 which is generally found to be increasing with time and thus requires immediate corrective measures lest the situation becomes totally uncontrollable. The present situation is as bad as in other metropolitan Indian cities, although it seems to have somewhat improved as indicated by the latest 20012005 data in comparison with the past 1988-1989 and 1994-1999 data, but much more still needs to be done. In addition to the industrial and vehicular pollution, the agricultural pollution due to the burning of wheat and rice straws by the farmers should also be checked because it also creates tremendous pollution in the atmosphere.

[

Introduction The city of Ludhiana in Punjab occupies a place of pride on the industrial map ofIndia and can be rightly called the home of small scale and household industries, and is thus popularly known as the "Manchester of India". There has been a rapid growth of industries in Ludhiana, especially, after the independence of the country. The growth has further been enhanced due to various facilities and incentives provided to the industrial entrepreneurs by the Government for setting up industry in the industrial areas and focal points in Ludhiana, Punjab, India. Thus, most of the industrial activities have been confined to the developed industrial areas. However, there is also a mushroom growth ofmajor industries along the G.T. Road towards Ambala as well as towards Amritsar. Major sources of air pollution in Ludhiana

)

years, an increasing emphasis has been placed on the use of rice husk as an alternate fuel due to its easy availability and lesser cost. Since rice husk contains cellulose and resinous substances, its burning increases smoke content in the air causing irritation to the eyes and breathing problems. Particulate matter from the rice husk burning is either ash or carbonaceous material resulting from incomplete burning. More than 2000 metric tons of rice husk is burnt every day by the industry as fuel which results in significant amount ofunburnt carbon and particulate matter along with gaseous pollutants which are carried over to the atmosphere with fuel gases. In addition to the burning of rice husk, air pollution in the city is also caused by burning of flue coal and oil, etc.

Major industrial sources of air pollution in Ludhiana are (i) textile industry including dyeing, fmishing, and wool combing, (ii) miscellaneous industry like food products, card board mills, steel re-rolling mills, vegetable ghee mills, and chemical industries, etc., and (iii) arc furnaces, cupola furnaces, and induction furnaces, etc. Compared to these, emissions of other industrial sources in Ludhiana are of lesser importance.

The total number of industrial units in and around Ludhiana city has increased from 6918 in 1972 to 79000 in 1993, which has now increased further also. There are about 1585 units, which are highly polluting and fall under the red category of industries. Out of the total 1585 highly polluting units, about 1075 are contributing substantially towards air pollution. Due to rapid urbanisation and industrialisation in this town, its population has also increased from 10.411akhs in 1991 to almost double now.

A majority of these industries use steam as the heat transfer medium. The predominant fuel utilised for the production of steam is coal, fuel oil and high speed diesel. Shortage of conventional fuel has generated interest in utilisation of the agro-residues such as paddy straw, wheat straw,etc., whichhave a relatively low calorificvalue. In recent

A good fraction of the air pollution in the city originates from the vehicular traffic and railway operation, particularly, in the vicinity of the railway station and locomotive yard. In Ludhiana, some of the roads have not been metalled and some are damaged due to heavy traffic load and lack of regular repair. Substantial dust remains in

*DepartmentofAgronomy, AgrometeorologyandForestry, Punjab Agricultural University, Ludhiana

- 141 004, Punjab, India

A case study of degrading urban air quality over Punjab, India suspension due to heavy traffic intensity causing poor visibility, respiratory problems and eye irritation in addition to general nuisance. There has been a rapid increasein the number of vehicles in the city overthe past few years. In Ludhiana, there are about 5.5lakh vehiclesincludingthree-wheelers,scooters,cars,motor cycles, trucks, and buses, etc. Scooters and motor cycles are the major transport source in the city. These along with threewheelers are the major contributors of carbon monoxide (CO) and hydro-carbons (HC) pollution in Ludhiana. The diesel powered heavy vehicles add to the air pollution problem by emittingoutjet black smoke.The problem is furtheraggravated whensomevehiclesuse adulteratedpetrol mixed withkerosene

oil. The emissions from such vehicles are very high in Suspended Particulate Matter (SPM) such as carbon and soot particles resulting in smoke, and noise pollution.

Dispenion conditions in Ludhiana The concentration of air pollutants and their impact on human health,-plants, and materials not only depends on the emissions but also on the way the air pollutants after their emissioninto theatmosphereare dispersedand finallyremoved. This period is called the transmission period for which the '.

main climatological factors of importance include wind direction, wind speed, and atmospheric stability. It is thus possible to discuss in a qualitative way three significantly different periods, such as the monsoon period (July to September), the summer period (April to June), and the winter period (October to March), which include the equinoctial periods also.

During the monsoon period, most factors of influence result in low concentration of pollutants. While the wind speed is moderate, other factors like high rainfall and washout, etc., lead to decrease of pollutants. The summer period is characterised by high solar radiation, high wind erosion, moderate stability and almost zero precipitation without any washout. There is thus high SPM since wind erosions due to high wind speed and minimal vegetation cover and also burning of agricultural residues lead to high SPM background concentration. On the other hand, expected concentration of pollution during the winter period is in the medium range, although high concentration of the SPM during October and November gives an indication that burning of the agricultural residues after the monsoon harvest might have a substantial impact on air quality. Methodology of air pollution monitoring The entire area ofLudhiana city has been studied on the basis of land use pattern and micrometeorological conditions. The land use pattern, wind conditions and also the WHO criteria that the monitoring stations should

represent background, residential, commercial and industrial areas have been kept in mind while selecting the locations of monitoring stations. Thus, three stations were set up at the following locations: (1) Milk Plant representing the background concentration of the pollutants, (2) Rita Sewing Machine representing highly industrialised area of the city, and (3) PPCB Office Building! Vishavkarma Chowk in Industrial Area-B of the city. SPM in the ambient atmosphere in the size range of 0.1 to 100 microns (mm) were collected on 8" x 10" glass micro fibre sheets by means of high volume air samples and estimated gravimetrically. Oxides of Nitrogen (NO.) were determined by bubbling the ambient air samples through a solution of sodium arsenite and sodium hydroxide, and then determined spectrophotometrically. Analysis of all the pollutants such as the SPM, NO., and S02' etc., was conducted as per I the prescribed standard methods (Anonymous, 1992). Regular monitoring was started at all the stations in June 1988 with the Punjab Pollution Control Board (PPCB) Office Building presently located in industrial area-B of the city having recorded its regular observations there subsequently. Monitoring was done at all the stations thrice a week. SPM was monitored for 24 hours with 8 hours averaging, whereas N02 and S02 were monitored for 24 hours with 4 hours averaging. The SPM, N02 and S02 data for the above mentioned stations has been analysed for 3 time periods, namely, (i) March 1988-December 1989, (ii) 1994-1999 as discussed by Sehra (2001),2 and (iii) 2001-2005. In these observations, the f11"sttime period, however, does not include the S02 monitoring. For the second time period, data is presented in the form of annual averages, but the latest third time period includes both the monthly as well as annual average concentrations of these parameters. Results and discussion The results of this investigation are presented in Table 1 and Table 2. The. seasonal influence of varying weather conditions on the SPM, NO. and S02 concentrations is well pronounced with their annual cycles showing two maxima and two minima. The first maximum occurs during the pre-monsoon summer months of AprilJune. This maximum coincides with strong surface winds and a generally dry atmosphere which increases natural wind erosion. The following monsoon minimum is well developed and caused by factors such as increased vertical dispersion, washout by monsoon rains and suppressed wind erosion. This minimum is followed by a maximum during the months of October and Nevember possibly due

PamJjit Singh Sebra Table 1: Atmualaverage concentrations ofSPM, NOz and SOz All values in Ilglm3 Year

1988 1989 1994 1995 1996 1997 1998 1999 2001 2002

2003 2004 2005 Standard values Annual 24bomty average IM!'IIge

SPM Site-I Site-2

'lA7 566

313 525

213

Site-3

490

509

450 471

NOz Site-I 26 Site-2 33 Site-3 Z2

21

51

29 34

SO 51

SOz Site-1

-

-

Site-2

-

-

-

-

Site-3

-

260 495

368 413

314

321

143

588 548

526 537

234 203

160 229 278

196 289

181 2S4

22S

331

40

30

30 33 33

31 36

33 38

40 40

31 31

40

ro

21

11

11

10

16

214 266 233

70 360 360

100

34

15

37 44

00 00

30 120 120

15

30

436 336

425

43

42

SO

45 44

45 45

46 41 42

21

15

18

22

16

17

21

11

12

12

21

21

00

120

21

11

12

12

24

22

00

120

263 48 SO

21

21

251

19

-

16

SOO SOO

-

Site I VerkaMilk Plant, Site2 Rita Sewing Machine, Site 3 PPCB Pffice BuildinglVishavkarmaChowk in Ludhiana,Punjab during 198889,1994-99 and 2001-2005. Standard values of the SPM, NOz' and SOzgiven in the last colunms are derived from the annual arithmetic mean of minimum 104measurementsin a yeartaken twice a week 24 hourly at uniform intervals.Minimum and maximum values for the period 19882005 are underlined.

to the burning of agricultural residues after the monsoon harvest. It is difficult to relate the following secondary rninimllm during the winter months January-March to the prevailing atmospheric conditions. Quite interestingly, the background station at the Verka Milk Plant shows the most pronounced seasonal variation of the pollutants concentrations. This is possible because industrial emissions usually show no seasonal variations. The seasonal variations of NOz and SOz are less pronounced but are recognizable, in particular, its monsoon minimum and two pre/post monsoon maxima. It is clear from Table 2, which gives the monthly average values of SPM, NOz and SOz for the period from 2001 to 2005, that the minimum values of SPM at the sites 1, 2 and 3 in 2001 were 76, 103 and 1411lg/m3in the months of July and September during the monsoon season due to the washout of the pollutants by the monsoon rains. This trend of minimum SPM during the monsoon period generally continued for 2002, 2003, .2004 and 2005 also with small variations at some sites due to variations in the monsoon rains. The maximum values of the SPM at three different sites 1, 2 and 3 in 2001 were found

to be

177, 341 and 289

llg/m3in December, September and July. These were 296,

339 and 352 llg/m3 in the months of December, April and December (all in 2005), respectively, at site 1, 2 and 3, due to wheat and paddy straw burning by the farmers in their fields after rabi and kharif crops harvesting in the months of April and September/October. This trend was noticed in the other years also with small variations depending upon the natural meteorological conditions. Further, the data is interpreted in the form of general patterns, such as comparison of mean values, the general influence of wind direction which transports the various pollutants to the sampling site, and the seasonal variations where the influence of varying weather conditions can be easily observed. From a general overview of the statistically relevant values of SPM of the present investigation, it is found that the SPM values at the Verka Milk Plant station are significantly lower than those of the other stations. The difference "between this station and the other stations representing industrial areas such as the Rita Sewing Machine is remarkable in their SPM values, although a greater data collection is further required for establishing these fmdings on a flfm footing. By setting the SPM average concentration at the Verka Milk Plant (background station) as 100%, relative SPM values at the Rita Sewing Machine (industrial area) was

A ease study of degrading urban air quality over Punjab, India Table 2 : Monthly average values of the ambient air quality data ofSPM, NOz and SOz for the period 2001 to 2005 at three sites

y

.

Month Jan

-

Site 1 SPM

NOx S02 Site 2 SPM

-

D»1

NOx S01 Site 3 SPM

-

NOx S02 Site 1 SPM

-

NOx S02 Site- 2 .SPM D)Z

NOx SO, Site- 3 SPM NOx S02 Site 1 SPM

-

NOx S02 Site 2 SPM

-

D)3

NOx S02 Site- 3 SPM NOx .S02 Site- 1 SPM NOx SOz Site- 2 SPM

3XM

NOx SO, Site 3 SPM

-

NOx S02

Feb

Mar

128 115 30 31 11 11 242 ZlO 31 31 11 11 228 217 31 31 13 11 113 128 32 32 13 13 180 168 32 .32 13 14 298 325 32 32 13 13 228 187 '29 '29 10 9 247 218 31 34 12 12 145 128 30 .35 11 11 169 119 44 36 13 13 Zl2 193 41 55 22 19 ZlI 280 OJ 79 28 25

136 28 10 219 '29 10 187 '29 11 149 31 12 190 31 12 286 31 12 182 30 11 243 32 11 163 32 11 148 30 16 192 J7 319 75 '29

Apr May 176 172 31 31 12 12 236 244 31 31 12 12 232 231 31 31 12 12 206 20S 31 32 12 12 273 .26S 32 32 12 13 315 248 32 32 12 12 224 206 30 31 9 10 394 244 33 35 11 11 170 20S 32 43 9. 10 202 195 30 '29 15 15 223 184 39 34 18 16 292 395 56 6'2 26 19

June 125 31 10 155 31 10 228 31 10 20S '29 13 209 31 13 Zl6 32 13 234 34 11 360 39 12 204 42 10 192 33 12 212 32 14 282 57 14

July 76 31 12 103 31 11 289 31 11 192 31 11 267 31 11 290 34 11 121 28 9 286 39 9

160 31 15 357 39 16 315 ifl

21

Aug 124 31 12 249 32 12 2JJ7

32 12 % ZI 9 163 33 11 240 34 11 132 24 11 325 '29 12 Zll Zl '13 217 '29 16 261 34 249 54

.

Sept

Oct

Nov

160 Zl 11 341 30 10 141 31 10 84 25 8 171 33 11 ZlI 33 10 136 Zl 13 Zl9 ZI 13 321 44 14 246 30 17

171 32 10 324 34 11 150 36 11 158 '29 9 212 35 11 2'29 39 12 199 36 11 334 42 12 268 SO 13 192 36 16 263 38 26 489 58 28

152 177 30 31 12 12 231 197 33 31 13 13 163 159 32 31 13 12 164 222 33 31 11 11 310 344 J7 35 13 12 420 134 39 30 15 12 249 2S7 38 41 10 12 302 235 42 46 13 14 306 292 49 56 18 16 217 189 34 30 22 18 344 Zl2 41 36 31 23

m 34 23 303 55 23

5(J7

61 31

Dee

ZlO

51 ZI contd...

P~it

SinghSehra

Apr 281 33 19 339 36 24 213 52 21

May 219 31 18 Z79 35 10

contd...Table 2

Month Jan

Year

-

Site 1 SPM

NOx S02 Site 2 SPM

-

2005

NOx 802 Site 3 SPM

-

NOx 802

163 26 14 219 33 19 166 35 14

Feb

Mar

159 28 15 230 33 17 122 32 18

155 31 19 195 39 10 154 49 22

June

320 48 22

zn 32 10 300 37 10 313 21

July 185 31 10 264 40 10 235 41 10

Aug 145 32 10 230 33 21 199 42 23

Sept 167 36 21 217 42 23 185 48 24

Oct

Nov

Dee

m

295 46 26 320 47 26 341 46 26

296 37 21 330 36 21 352 39 22

26 274 43 13 213 47 26

-

Site I : Verka Plant (Outskirts of the city), Site 2 ; Rita Sewing Machine (Industrial area), and Site 3 : Office Building / Vishavkarma Chowk (Industrial and residential area) Minimum and Maximum values of the SPM are underlined in this Table Source;- P.P.C.B.

found to be 200%. Since the Verka Milk Plant station is located in the south-western (SW) outer fringe ofLudhiana, it is not directly affected by industrial and commercial residual emissions as the main wind direction is north-west (NW) and south-east (SE), this result seems quite plausible. This station is thus mainly influenced by the background concentration of the SPM. The influence of industrial dust emission can be seen through the higher values of the SPM in the industrial area. The average N02 concentrations at all the stations do not differ significantly. It seems that emission, dispersion, and chemical reaction pattern of this air pollutant, i.e., (N02) needs further studies to understand it completely. In particular, more rural background stations which are uninfluenced by urban emissions are needed. It also seems that the stations are more influenced by emissions in their vicinity itself. Conelusions The results of monitoring of air quality in Ludhiana during the period 1988-1989, and those of the annual averages of three pollutants concentrations during the periods 1994-1999 and 2001-2005 including their monthly averages for 2001-2005 have been analysed, which show that the present situation is far from satisfactory. The minimum and maximum values of the SPM at site1 in the outskirts of the city were found 143 and 363 Ilg/m3 in 2001 and 1997, respectively, while their values in the Industrial area at site 2 and 3 were found 229 and 588 J1g/m3 in 2002 and 1998, and 203 and 548 J1g/m3in 2001 and 1998, respectively, indicating somewhat improvement in the

situation through the role played by the 'PPCB' and public awareness.

-

Although the latest data for the period 2001 2005 shows soml: improvement in air quality as compared with the past periods 1988-1989 and 1994-1999, but still much more needs to be done. The analysis of the past and latest data also shows that besides the industrial and vehicular pollution, there is tremendous agricultural pollution also due to the burning of wheat and rice straws by the farmers in their fields after harvesting of their rabi (wheat) and kharif (rice) crops in April and September/October months, which also need to be checked by all means for better air quality and healthy living. Farmers are resorting to wheat stubble and rice straw burning after harvesting their wheat and rice crops in April and September/October. They think that fire is the most economical and easiest way to clear their fields for further sowing.But they are ignorant of the fact that fire in their fields kills friendly pests and bacteria that increases the fertility of soil. It also brings about adverse environmental changes. The SPM left in the air due to fire are also considered to be one of the reasons for dense fog/smog that engulfs the region in winters. Besides, the SPM generated due to fire can cause respiratory and other health problems for the people. The farmers themselves are worst affected as they come in direct contactwiththe ill-effectsoffield fires.It is,therefore,absolutely necessary to spread its awareness in the farmers so that they

A case study of degrading urban air quality over Punjab, India can stop burning wheat stubble and rice straw, and use it for making manurefor their fields. The dependence on the relevant factors of influence is absolutely necessary. Monitoring of the prevailing air pollution bas thus to be intensified by adding more stations and expanding to other components, particularly, carbon monoxide (CO) and hydrocarbons (HC), etc. Knowledge of the chemical composition of the Suspended Particulate Matter is necessary to assess its possible health impacts. Air quality modelling by use of a dispersion model based on an emission inventory would be a vital prerequisite to optimise a sound monitoring programme for understanding the cycle of relevant air pollutants in a better way and to plan necessary measures to control air pollution in Ludhiana. Acknowledgements The author is grateful to the Punjab Pollution Control Board (PPCB), VatavaranBhawan, NabhaRoad, Patiala-147 00 I, Punjab, India, for providing all the required information for the present study.

ReferenceS

1.

Anonymous, A Report on Status of Ambient Air Quality of Ludhiana City, SAAQRlPPCB/1I1992, Punjab Pollution Control Board (PPCB), Patiala 147001, Punjab, India (1992).

-

2.

Sebra,P.S.,HazardousPollutionProblemoverLudbiana, Punjab, India. Third International Conferenceon UrbJn Air Quality and Fifth Saturn Workshop, Measurement, Modelling and Management 19-23 March 2001, The Poseidon Hotel Resort, Loutraki, Greece. Organized by the Environmental Physics Group of the Institute of Physics, London, the Environmental Research Laboratory INTRP, NCSR "Demokritos", and the University of Hertfordshire, Hatfield ALl09AB in collaboration with SATURN, TRAPOS and C()ST71S, U.K, Supported by AWMA, IUAPPA and EURASAP. Paper No. UAP.Pl.18, Extended Abstracts CD-ROM, Institute of Physics, 76 Portland Place, London WIN 3DH,UK.