56 Nu clear Tech nol ogy & Ra di a tion Pro tec tion –1/2009

ASSESS MENT OF ENVI RON MEN T AL GAMMA DOSE IN NORTHERN RECHNA DOAB IN PAKI STAN

by

Abdul JABBAR1,2, Arshad S. BHATTI1, Syed S. AHMAD2, Waheed ARSHED2, and Perveen AKHTER2

Received on Febru ary 18, 2009; accepted in revised form on March 27, 2009

En vi ron men tal gamma ra di a tion lev els in north ern Rechna Doab, Pa ki stan, were mea - sured as a part of sys tem atic study aimed at the es tab lish ment of the back ground data base of ra di a tion and ra dio ac tiv ity lev els. The mea sure ments re ported in this pa per were made with por ta ble ra di a tion mon i tor which em ployed GM tube and was cal i - brated against second ary standard dosim e try system. The aver age absorbed dose rate in air was deter mined to vary from 86.0 nGy/h to 139.1 nGy/h with the mean value of 109.1 nGy/h. The an nual ef fec tive dose re mained within the range of 105.47 mSv to 170.54 mSv with its av er age value of 133.73 mSv. These en vi ron men tal ra di a tion doses in the area were com pa ra ble with those re ported for other coun tries. It was con cluded that the prev a lent ra di a tion lev els did not pose any sig nif i cant ra dio log i cal health haz - ard to the pop u lation.

Key words: en vi ron men tal ra di a tion, gamma ra di a tion, ra di a tion mon i tor ing, gamma dose, Rechna Doab

INTRODUCTION Punjab consis ts mostly of plains north and south of the an cient Salt Range, which stretch from east to The province of Punjab com prises eight ad- west. Punjab can be di vided into five major physi cal min is tra tive di vi sions ex tend ing over an area of regions: (I) Northern Mountai ns, (II) South-West ern 205.346 sq. km (97.192 sq. miles). Ac cording to the Moun tains, (III) Potohar Platea u, (IV) the Upper Indus result s of 1998 census, the popu la ti on of the prov- Plain, and (V) the Deserts. In the north, there are the ince stands at 71.5 mil lion (about 55% of the total outer ranges of the Hi mala yas: Murree and Kahuta pop u la tion of Pa ki stan) com pared with 47.12 mil - hills in the north and the Pubbi hills of Gujrat in the lion of 1981 popu la ti on census figures. The popu la - south [1]. tion densit y in the province is about 348 per sons per Ag ri cul ture is the most im por tant in dus try in sq. km. The province of Punjab is the most popu lous Punjab. Wheat, rice, sugar cane , fruit, tobacc o, cot ton, one, and therefore the as sess ment of radi a ti on doses and many other crops flourish in the soil of Punjab. is a rel a tively im por tant is sue. The province of Punjab is criss-crossed by ca nals as a result of which the area is now a huge oasis where there are hun dreds of new settlements.

Nu clear Tech nol ogy & Ra di a tion Pro tec tion Sci en tific pa per UDC: 539.166:614.87 Study area BIBLID: 1451-3994, 24 (2009), 1, pp. 56-60 DOI: 10.2298/NTRP0901056J The Rechna Doab can be clas sified as one of the 1 De part ment of Phys ics, main regions of Punjab. Plain areas of Punjab are di - COMSATS In sti tute of In for ma tion Tech nol ogy, Islamabad, Pa ki stan vided into nat ural regions based on its vari ous rivers, 2 Health Phys ics Di vi sion, since the name Punjab is based on its 5 main rivers. Pa ki stan In sti tute of Nu clear Sci ence & En gi neer ing (PINSTECH), Rechna Doab, com prising about 28.500 square kilo - Nilore, Islamabad 45650, Paki stan meters, is en closed by the river Chenab and river Ravi E-mail ad dress of cor re spond ing au thor: on the northwest and southeas t, re spec tively, with the mand_tegha@ya hoo.com (A. Jabbar) piedm onts near the Jammu and Kashm ir boundary in A. Jabbar, et al.: As sess ment of En vi ron men tal Gamma Dose in North ern Rechna Doab, 57 the northeas t. Its longi tude is 71o 48' to 75o 20' E and Ex ter nal ex po sures out doors arise from ter res- lat i tude 30o 31' to 32o 51' N. Rechna Doab is about trial radionuclides pres ent at trace lev els in all soils 403 km long in southwest direc ti on and has a maxi - and from cosm ic radi a ti ons. The specif ic levels in soils mum width of about 113 km [2]. are re lated to the types of rocks from which the soils The area is interfluvial and is southwest erly orig i nate. Higher ra di a tion lev els are as so ci ated with sloped. In the upper part of the Rechna Doab, the slope igne ous rocks, such as granit e, and lower levels with is about 380 cm/km to about 9 cm/km [3]. Physio- sed i men tary rocks. There are ex cep tions, how ever, as graph i cally, the Rechna Doab can be char acter ized by some shales and phosphate rocks have a rela ti vely the fol low ing units: high content of radionuclides. Many surveys have – Kirana hills – though minor when com pared with been made to deter mine the background levels of the allu vial com plex, but very prom inent, radionuclides in soils, which can in turn be relat ed to – ac tive flood plains in the vi cin ity of the rivers the ab sorbed dose rates in air. The later can eas ily be Ravi and Chenab, measured di rectly, and the re sults of such measure - – abandoned flood plain, and ments provide an even more exten sive eval ua ti on of – bar upland – an ele vate d land be yond the reach of the back ground ex po sure lev els in dif fer ent coun tries flood wa ters of the rivers. [6]. The cos mic expo sure which is the secret com po - nent of the background radi a ti on dose is relat ed to the al titud e of the place of in ter est. Geology Gamma dose measure ments have been con - ducted in dif ferent areas of the country through soil The con sol i dated ex posed rocks near Chiniot, radionuclides, but not in a sys tematic way. Like the Sangla, and Shahkot repre sent the rem nants of the bur- large-scale surveys done in many other countri es of ied ridge of meta morphic or igne ous rocks form ing the the world, this first sys tematic and ex ten sive study of base ment of the al lu vial de pos its in Rechna Doab. this nature was done by using a cali brat ed dose rate These indurated rocks are known as Kirana hills and me ter which gives in stan ta neous results. are of the pre cam brian age. These rocks cover the cen - The objec ti ve of the pres ent study was to develop tral part of Rechna Doab making the longi tu di nal sec - the base line natu ral background radi a ti on dose data for tion across its width. The uncon sol i date d allu vial de- var i ous re gions of north ern Rechna Doab, com prising pos its are of the pleis to cene to re cent in age and are dis tricts Sialkot, , Narowal, and Hafizabad. overly ing the precam brian base ment rock. These were A detai led radi a ti on survey was made by using a quite depos it ed in a subsid ing trough by the ances tral and sen si tive and well cal i brated ra di a tion dose rate me ter. pres ent trib u tar ies to the river Indus. The allu vial fill is For unknown measure m ent patter n the northern more or less hom oge neous in nature , and has littl e con- Rechna Doab was di vided into grids of 24 ´ 28 sq. km, ti nu ity ver ti cally or lat er ally, in di cat ing di verse cover ing the whole area under the study. The re sults depositional envi ron m ents from time to time caused have been prepared and present ed in this pa per. by consta nt change in the stream courses [4]. The allu vial sed iments con sist mainly of gray, gray ish brown, fine to medium sand, silt, and clay. MATERIALS AND METHODS Gravel or very coarse sand is uncom mon. Kankers, a cal ciumcar bon ate ma te rial of sec ond ary or i gin is as so - Ra dio log i cal mon i tor ing was per formed by us ing ci ated with fine-grained strata. Clay is gen er ally found in lenses. The ori gin of clay has not been ascer tai ned the ra di ation dose rate meter of FAG, Ger many, model but pre sum ably it is re peat edly reworked loess. Of the FH40F4 (fig. 1). It em ployed a GM tube as the acti ve allu vial com plex, sand forms the areas of fairly de tec tor hav ing en ergy in de pend ent re sponse from 45 transmissive aquifer mate ria l in which ground water keV to 1.3 MeV. The measure ment with FAG dose rate occurs under water table conditions [2]. meter , owing to the insta nta neous re sults and the easil y When the Earth was formed, the mate ri als from porta ble na ture with alm ost nil transport charges, was which it was made con tained ra dio active ele m ents. pre ferred over thermoluminescent do sim e ter (TLDs) About 70 radionuclides have been found in nature . technique which require d longer expo sure times (in These can be divided into two main cate go rie s: months) to re cord back ground ra di a tion lev els and cosmogenic radionuclides produced by cosm ic rays, e. there af ter re quired the in di rect eval u a tion of the re sults g. 3H, 7Be, 14C etc., and pri mordial radionuclides, in the lab o ra tory. The re liabil ity of the dose rate meter which are of two types. First being singly occur ring result s was assured by its cali bra ti on in the Second ary radionuclides with long half lives e. g. 40K, 87Rb, Stan dard Do sim e try Lab o ra tory (SSDL), PINSTECH, found in all rocks, soil, water , and living or ganism Pa ki stan, whose measure ments are trace able to Pri mary even the hum ans. The second type consis ts of the Standard and are ensured by the Inter nati onal Atomic mem bers of the fam i lies of ra dio ac tive heavy el e ments Ener gy Agency (IAEA) through the postal dose pro duced in 238U, 235U, and 232Th de cay series [5]. intercomparison [7]. The measure ments were made 58 Nu clear Tech nol ogy & Ra di a tion Pro tec tion –1/2009

The an nual ef fec tive dose, AED, was es tim ated us ing the fol low ing con ver sion

AED [mSv] = D×24×365×0.7×0.2×10-3

Table 1. Environmental gamma radiation levels in northern Rechna Doab, Pakistan

Average Annual absorbed effective Location Latitude Longitude dose rate dose in air [nGyh–1] [mSv] Gujranwala 32° 09' N 74° 07' E 133 163 32° 28' N 74° 05' E 121 148 Aiman Abad 32° 01' N 74° 13' E 113 138 32° 23' N 74° 08' E 106 130 Ahmad Nagar 32° 20' N 73° 59' E 114 140 Fig ure 1. A view of FAG dose rate Head Khanki 32° 22' N 73° 59' E 93.3 114 me ter used dur ing present study Rasul Nagar 32° 19' N 73° 47' E 87.8 108 Kalianwala 32° 17' N 73° 44' E 113 139 during the period of April-June 2008, at a refer ence 32° 16' N 73° 41' E 123 150 height of 1 meter above the ground level in the open air. Rasulpur Tarar 32° 03' N 73° 27' E 105 129 The present study area, northern Rechna Doab (fig. 2), Gajar Gola 32° 04' N 73° 43' E 105 129 was di vided into 24 ´ 28 sq. km spati al grids to evenly Uddowali 32° 06' N 73° 54' E 96.9 119 Killah Didar dis trib ute the data col lec tion points. It was as sured that Singh 32° 07' N 73° 59' E 124 151 read ing at ev ery data point was a true rep re sen tation of Noshehrah 31° 59' N 74° 09' E 131 160 the ra di ation level. Ten to fif teen read ings were taken at Virkan each loca ti on for this purpose and their mean value was 31° 56' N 74° 13' E 86.0 105 convert ed to the absorbed dose rate in air [8]. The mini - Sadhuke 31° 53' N 74° 14' E 89.7 110 mum, maxi m um, and mean value of the absorbed dose Manguke 31° 47' N 74° 01' E 86.9 107 rate in air and the out door ef fecti ve annual dose from Hafizabad 32° 03' N 73° 42' E 113 138 ter res trial or i gin de rived from these mea sure ments are 31° 53' N 73° 15' E 120 147 menti oned in tab. 1. Wainkay Tarar 32° 13' N 73° 35' E 123 150 The av er age ab sorbed dose rate in air, D, was Chak Bhatti 32° 05' N 73° 24' E 103 126 cal cu lated us ing the fol low ing re la tion: Jalalpur Nau 32° 03' N 73° 23' E 96.9 119 Sukhayki 31° 49' N 73° 35' E 93.3 114 D [nGy h-1 ] = 9.15´ dose [mRh –1 ] Kishan Garh 31° 47' N 73° 26' E 126 155 Sialkot 32° 27' N 74° 33' E 130 159 Sambrial 32° 30' N 74° 20' E 114 140 Kulu Wal 32° 34' N 74° 21' E 94.2 116 Head Marala 32° 40' N 74° 28' E 103 126 Chaprar 32° 34' N 74° 29' E 114 140 Chuvinda 32° 21' N 74° 37' E 86.9 106 Mundeki 32° 17' N 74° 32' E 139 171 Daska 32° 17' N 74° 21' E 103 127 32° 11' N 74° 22' E 105 129 Sutra 32° 09' N 74° 28' E 115 141 Merajke 32° 24' N 74° 46' E 102 125 Norowal 32° 06' N 74° 51' E 96.1 118 Zafarwal 32° 20' N 74° 55' E 131 160 Chak Amro 32° 15' N 74° 08' E 112 137 Noor Kot 32° 11' N 74° 06' E 120 147 Jassar 32° 05' N 74° 55' E 98.8 121 Talwindi Bhindran 32° 06' N 74° 40' E 105 129 Minimum 86.0 105 171 Fig ure 2. Map of study area, north ern Rechna Doab, Maximum 139 Pa ki stan Average 109 134 A. Jabbar, et al.: As sess ment of En vi ron men tal Gamma Dose in North ern Rechna Doab, Pakistan 59 where 0.7 is Gy to Sv con ver sion fac tor, and 0.2 is the oc cu pancy fac tor.

RESULTS AND DISCUSSION

As shown in tab. 1, the absorbed dose rate in air (in clud ing cos mic ray con tri bu tion) in north ern Rechna Doab has been found to vary from 86.0 nGy/h to 139.1 nGy/h with the mean value of 109.1 nGy/h. The mean an nual ex ter nal ef fec tive dose due to the nat u ral ex po sure of pop u la tion to the ex ter nal ter res trial ion iz ing ra di a tion (40K and de cay prod ucts of 238U and 232Th) [9] with the contri buti on of cosm ic radi a ti on in the annual ef fecti ve dose com es out to be 133.73 mSv. The radi a ti on levels as shown in tab. 1 indi cat e the non-exis - tence of any hot spots and the vari ati on is consid ered Fig ure 3. Com par i son of an nual ef fec tive dose with quite norm al. Although this data set is a very pre lim inary differ ent countries of the world one, it gives a sugges ti on that the radi a ti on levels are fa- vour ably low not only for the dwellers but also for any future construc tion of nucle ar power plants near the quite big, it leaves the oppor tu ni ti es for any future re- rivers of the area. searcher to fill the gap by reduc ing the grid area. Ta ble 2 summa rizes the re sults of simi lar stud ies The south Asian and east Asian regions are wit- which had been carrie d out in dif ferent areas of the nessing a gradual but fast prom oti on of nucle ar power. world. The world aver age annual ef fecti ve dose has been Paki sta n is eager to fill the supply and dem and in the reporte d as 70 mSv [5]. The annual ef fecti ve dose in the ener gy gap with the de velop m ent of nucle ar ener gy. north ern Rechna Doab was found to be rel ati vely higher The area un der study, as al ready in di cated, lies be - as compared to the world av er age as well as south west - tween two inde pend ent rivers, and may have more ern Ni geria and southeas tern Turkey [9, 10]. However , it than one site for nucle ar power reac tor insta lla ti ons. was compar atively lower when compared with simi lar Putt ing the pres ent study in this perspec tive further en- values in Hong Kong, Ma lay sia, west ern Sudan, and hances its impor tance as well as the need for fu ture Costa Rica [11-14], as shown in tab. 2 and plot ted in fig. sim ilar studies in the area to cover the gap left due to 3. These com pari sons show that the annual ef fecti ve dose un ex plored ar eas. in the northern Rechna Doab lies in the same range as re - ported for vari ous parts of the world. To the best knowl edge of the authors, this is the CONCLUSIONS first study of its na ture in Rechna Doab. It is be lieved that the data col lected and pre sented in this pa per will act as a We conclude for our studies that the annual ef - ready ref er ence for any fu ture ac tiv ity/de vel op ment fecti ve dose in northern Rechna Doab, Pa ki stan, lies in wherein each study is a reg u latory re quire ment, e. g. the a wide range reporte d for vari ous places in the world. construc tion of a nucle ar power plant for the electri cit y We also conclude that the envi ron m ental dose is pri- gener a ti on. Although the grid selec ted in the study is maril y due to the pri mordial radionuclides and cos mic ra di a tion since no en hanced ra di a tion lev els were found any where. Ta ble 2. Com par i son of an nual ef fec tive dose with differ ent countries of the world Annual Country effective Reference RECOMMENDATION dose [mSv] Nigeria 21.8 R.K Odunaike et al. (2008) For any fu ture work in the same area, it is recom - World average 70 UNSCEAR (2000) mended that the grid size should be reduced to obtai n Southeastern Turkey 74.7 A. Bozkurt et al. (2007) the background radi a ti on levels which will better cover the area. Northern Rechna 134 Present study Doab, Pakistan Hong Kong 198 W. Man-Yin et al. (1992) Malaysia 210 A.T. Ramli et al. (2005) REFERENCES Western Sudan 270 A. K. Sam et al. (2002) Costa Rica 740 P. Mora et al. (2007) [1] ***, At las of Pa ki stan, Sur vey of Pa ki stan, Rawalpindi, 1985 60 Nu clear Tech nol ogy & Ra di a tion Pro tec tion –1/2009

[2] Khan, M. A., Hydrogeological Data, Rechna Doab, South west ern Part of Ni ge ria, En vi ron men tal Re - 1978, Wa ter and Power De vel op ment Au thor ity Pa ki - search Jour nal, 2 (2008), 4, pp. 174-176 stan [10] Bozkurt, A., Yorulmaz, N., Kam, E., Karahan, G., [3] Greenman, D. W., Swarzenski, W. V., Bonnett, G. D., Osmanlioglu, A. E., As sess ment of En vi ron men tal Ground Wa ter Hy drol ogy of Punjab with Em pha sis on Ra dio ac tiv ity for Sanliurfa Re gion of South east ern Problems Caused by Ca nal Ir ri ga tion, Wa ter and Soil, Tur key, Ra di a tion Mea sure ments, 42 (2007), 8, pp. In ves ti ga tion Di vi sion, Bul le tin 6, WAPDA, 1967 1387-1391 [4] Kidwai, Z. U., The Ge ol ogy of Rechna and Chaj [11] Tso, M. Y W., Li, C. C., Terres trial Gamma Radi a tion Doab, Bul le tin 5, WASID, WAPDA, 1962 Dose in Hong Kong, J. Health Phys, 62 (1992), 1, pp. [5] ***, UNSCEAR, Sources and Effects of Ionizing Ra - 77-81 di a tion, United Na tions Sci en tific Com mit tee on the [12] Ramli, A. T., Sallehudin, S., Husin, W., Terres trial Ef fects of Atomic Ra di a tion (New York: UN), Gamma Ra di a tion Dose Study to De ter mine the Base - 2000 line of En vi ron men tal Ra dio log i cal Health Prac tices [6] ***, The 1990-1991 Rec om men da tions of the In ter - in Melaka State, Malay sia, J. Ra dio log i cal Prot., 25 na tional Com mis sion on Ra dio log i cal Pro tec tion, Pub li ca tions 60. Ann. ICRP, 21 (1991), 1-3 (2005), 4, pp. 435-450 [7] Zeb, J., Arshed, W., Haq, E. U., Ali, A., Orfi, S. D., [13] Mora, P., Picado, E., Minato, S., Natu ral Radi a tion En vi ron men tal Gamma Dose Mea sure ments in the Doses for Cosmic and Ter res trial Com ponents in City of La hore, Pa ki stan, The Nucleus, 39 (2002), 3-4, Costa Rica, Appl. Rad. And Isotop, 65 (2007), 1, pp. pp. 161-165 79-84 [8] ***, IAEA Tech ni cal Report Ser ies No. 110, Man ual [14] Sam, A. K., Sirelkhatim, D. A., Hassona, R. K., of Dosimetry in Radiotherapy, 1970 Hassan, R. E., Musa, E. H., Ahmed, M. M. O., As sess - [9] Odunaike, R. K., Alausa, S. K., Oyebanjo, O. A., ment of Gamma Dose Rate over a Sus pected Uranium Ijeoma, G. C., Alo, A. O., Measure ment of Radi a tion Min er al iza tion of Jebel Mun, West ern Su dan, Ra di a - Lev els in Re fuse Dumps across Lagos Me trop o lis in tion Pro tec tion Do sim e try, 102 (2002), 2, pp. 169-174

Abdul XABAR, Ar{ad S. BHATI, Sajed S. AHMAD, Vahid AR[ED, Pervin AKHTER

OCENA DOZE GAMA ZRA^EWA OKOLINE U SEVERNOJ OBLASTI REHNE DOAB U PAKISTANU

U severnoj oblasti Rehne Doab u Pakistanu izmereni su nivoi gama zra~ewa u okolini kao deo sistematskog prou~avawa kome je ciq da se uspostavi baza podataka osnovnog nivoa zra~ewa. U ovom radu izve{tava se o merewima koja su obavqena sa prenosivim monitorom zra~ewa koji koristi GM broja~ kalibrisan sekundarnim dozimetrijskim standardom. Utvr|eno je da se ja~ina sredwe apsorbovane doze u vazduhu mewa od 86,0 nGy/h do 139,1 nGy/h, sa sredwom vredno{}u od 109,1 nGy/h. Godi{wa efektivna doza kretala se u rasponu od 105,47 mSv do 170,54 mSv sa sredwom vredno{}u od 133,73 mSv. Ove doze zra~ewa okoline u ovoj oblasti uporedive su sa podacima za druge zemqe. Zakqu~eno je da preovla|uju}i nivoi zra~ewa ne predstavqaju nikakav radiolo{ki zdravstveni rizik za stanovni{tvo.

Kqu~ne re~i: zra~ewe u okolini, gama zra~ewe, moni tor ing zra~ewa, gama doza, Rehna Doab