Journal of Water Resource and Protection, 2012, 4, 32-38 http://dx.doi.org/10.4236/jwarp.2012.41005 Published Online January 2012 (http://www.SciRP.org/journal/jwarp) An Assessment of Biological Pollution in Certain Sector of Lower AL-Zab and River Tigris Waters Using Bacterial Indicators and Related Factors in Iraq Mohemid M. Al-Jebouri1, Muhsin H. Edham2 1Department of Microbiology, College of Medicine, University of Tikrit, Tikrit, Iraq 2College of Education, University of Tikrit, Tikrit, Iraq Email: [email protected] Received October 25, 2011; revised November 27, 2011; accepted December 28, 2011 ABSTRACT This study was conducted during 2004 utilizing selected sectors of River Tigris and the Lower Al-Zab River among Kirkuk and Salahaldeen Governerates of Iraq. Water samples from eight stations were analyzed for total coliforms, fe- cal coliforms, total viable counts of bacteria, Oxygen biological demand (BOD), water turbidity, electrical conductivity and temperature. The mean total viable counts (TVC,s) of bacteria isolated was almost 800 cells/ml. The means of total coliforms (TC) and faecal coliforms (FC) were almost 708 and 436 per 100 ml of water samples tested respectively.The oxygen biological demand was more than 8 mg/l. The mean of water tubidity was more than 35 ntu. The assessment of water electrical conductivity revealed almost 354 us/cm. The present study revealed a wide variation in the water qual- ity due to different pollution pressures affected the different sites of River Tigris and Al-Zab River waters. These water sources are used for drinking and other human activities. The Lower Al-Zab River was less affected by the mentioned factors compared to River Tigris The analysis of variance showed a significant difference between BOD values re- corded at different months and the P value was less than 0.5. The overall mean of BOD was 2.4 mg/l which is suitable for human consumption after drinking water purification process with reference to European characterizations 74/ 464/EEC of waters used as sources for drinking waters. Keywords: Bacterial Indicators; Pollution; River Tigris; River Al-Zab; Iraq 1. Introduction gations [8-10]. In addition to known environmental pollution and im- Fresh water bodies particularly rivers always considered pact on the human habitat, Iraq passed through a series of as a main source of drinking and relevant human uses for maintenance of life. These natural water bodies usually recent wars which made the local environmental situation under stress of environmental pollution including che- is more unique that needs more and more exploration for mical, physical and biological aspects that might turn the reevaluation of the degree of different aspects of pollu- nature of these waters to be risky for human beings uses tion including the biological aspect. The present study [1-5]. Environmental stress as well as human population aimed to investigate the bio-chemical parameters con- growth associated with an increased industrial and civil- cerning pollution of River Tigris and Lower Al-Zab ian activities can all cause a damage for the natural water River of Iraq. quality that might be necessary for human needs which lead to continuous environmental survey and assessment 2. Materials and Methods to reveal the degree of pollution impact particularly on 2.1. Description of the Area Studied raw water sources like rivers, lakes, springs and deep wells waters i.e. ground waters [6]. Raw water quality can The collection site No.1 was located at the end of the Ri- be assessed using various parameters particularly the bac- ver Al-Zab, Al-Hawija district, Kirkuk Governerate be- terial indicators of biological pollution [7]. Chemical and fore the junction of Al-Zab with the River Tigris at the physical factors affecting water quality have been util- Maddallah fields. The other sites of water were located ized for evaluation of degree of pollution and these in- on River Tigris; site No.2 (Al-Shag area) and site No.3 cluded oxygen biological demand, turbidity, electrical (Al-Shjara area) were located on the River Tigris in conductivity, temperature, and pH of waters under investi- Al-Hawija district, Kirkuk Governorate. The other five Copyright © 2012 SciRes. JWARP M. M. AL-JEBOURI ET AL. 33 sites were located on River Tigris passing through the used by Al-Shwany [12]. Salahaldeen Governorate from Al-Baiji to Samarra dis- tricts and they were; Al-Mazraa (S4), Tikrit University 2.6. Biological Oxygen Demand (BOD) (S5), Tikrit Bridge (S6), Al-Oja (S7) and Abo-Dalaf (S8). BOD was estimated according to APHA [13]. 2.2. Collection of Water Samples 2.7. Bacteriological Study Sixty four water samples were collected from different All water samples were bacteriologically investigated for sites using sterile bottles. The samples were transported total viable counts (TVC, s), total coliforms (TC) and fe- to the laboratory in cooled container. The samples were cal coliforms (FC) using the conventional methods [1] collected from each site during January, February, March, and the most probable number techniques [14]. April, June, July, August and September 2004. 3. Results 2.3. Temperature of Water 3.1. Water Temperature Water temperature of each site was recorded using mer- cury thermometer at the time of sample collection [11]. The present results showed that the lower water tempera- ture was recorded at the station of Maddallah fields (S1) 2.4. Elecrical Conductivity on Al-Zab River when it was 8˚C at December (Table 1). The highest water temperature was recorded at Al-Oja This parameter was estimated using conductivity meter site (S7) during July which elevated to reach 25.2˚C. CDM83 (Denmark) according to Turki [11] methods. 3.2. Electrical Conductivity of Water 2.5. Turbidity The present study showed that the electrical conductivity The water turbidity was estimated utilizing turbidity meter of waters under investigation were varied and ranged be- (HANNA Instruments,Burtogal) according to methods tween 230 to 678 ms/cm (Table 2). Table 1. Water temperature (˚C) at the sampling sites. Sampling sites* No. Months S1 S2 S3 S4 S5 S6 S7 S8 Mean 1 January 8 8 8 9.2 8.4 8 8 8.3 8.2 2 February 9 10 10 11 10 10 10.3 11 10.2 3 March 10 10.4 10.5 11.5 13 13.2 13.2 13.8 12 4 April 13 14 14 15.3 15 15.2 15.3 15.3 14.6 5 June 18 18 18 20 22 22 22 22.2 20.3 6 July 22 22 22 23 25 25 25.2 25.2 23.7 7 August 20 20 20.3 22 20 20 20.4 22 20.6 8 September 23 23 23 24 24 24 24.2 24.5 23.7 Overall mean 15.4 15.7 15.7 17 17.2 17.2 17.3 17.8 16.7 *For explanations, see the text. Table 2. Electrical conductivity of water samples tested. Sampling sites No. Months S1 S2 S3 S4 S5 S6 S7 S8 Mean 1 January 295 233 251 287 312 298 301 298 283.9 2 February 370 482 414 230 280 370 273 290 338.5 3 March 237 366 263 408 422 393 442 372 362.9 4 April 406 366 390 526 484 377 389 373 413.9 5 June 675 415 315 378 382 348 379 366 412.4 6 July 302 368 348 338 350 340 355 337 342.3 7 August 243 293 297 394 293 281 316 389 312.1 8 September 355 386 393 412 418 332 328 334 369.8 Overall mean 360.4 363.6 331.6 371.6 367.6 346.8 347.8 345.5 354.4 Copyright © 2012 SciRes. JWARP 34 M. M. AL-JEBOURI ET AL. The lowest value was recorded at Al-Mazraa site (S4) during July (0.7 mg/l) and both stations were located on during January while the highest value was recorded at River Tigris. The BOD value (4.4 mg/l) was seen in Maddallah site (S1) during June which was 675 ms/cm. Abo-Dalaf site (S8) during February. The analysis of va- The lowest conductivity of Al-Zab River water (Maddal- riance showed a significant difference between BOD va- lah site; S1) was recorded during March. The lowest lues recorded at different months and the P value was electrical conductivity of River Tigris water was seen at less than 0.5. Al-Mazraa site (S4) at February, i.e. 230 ms/cm and the highest conductivity (526 ms/cm) was observed at the 3.5. Total Viable Counts (TVC,s) same site during April. The overall mean of the conduc- It was shown that the lowest number of heterotrophic tivity of both rivers waters was almost 354 ms/cm. bacteria i.e. TVC was isolated from the sample collected from Tikrit Bridge site on River Tigris at February (Ta- 3.3. Turbidity of Water ble 5) and the value was 11 × 10/ml. The highest viable The present study showed that the lowest turbidity value counts of bacteria was isolated from the water of Abo- was 18.04 (81.03 NTU) but the highest value was re- Dalaf (S8) on River Tigris during February and the value corded at Maddallah site (S1) of the River Al-Zab during was 324 × 10/ml. The highest value of recorded at Mad- April of the year (Table 3). dallah area(S1) during January when the bacterial num- The present study generally also showed that turbity ber was 223 × 10/ml. The heterotrophs were higher in was higher during cold months compared to hot seasons.