Comparative Composition of Volatile Organic ... - Springer Link

COMPARATIVE COMPOSITION OF VOLATILE ORGANIC COMPOUNDS IN THE WATER-SOLUBLE FRACTION OF DIFFERENT CRUDE OILS PRODUCED IN KUWAIT TALAT SAEED∗ and MAHA AL-MUTAIRI Environmental Sciences Department, Earth and Environmental Sciences Division, Kuwait Institute for Scientific Research, P.O. Box 24885, Safat-13109, Kuwait (∗ author for correspondence, e-mail: [email protected])

(Received 27 May 1998; accepted 14 June 1999)

Abstract. Kuwait’s desert was inundated, in 1991, with massive oil-spills from damaged well heads and from oil fires. Large volumes of seawater used for fire-fighting freely mixed with oil and then seeped into the ground. The dissolved compounds not only contaminated soil but also threaten to pollute groundwater. The composition of the volatile organic compounds (VOCs) in the water-soluble fraction (WSF), in seawater, of ten different crude oils produced in Kuwait and Kuwait crude oil (export) was investigated. The results showed that the composition of the WSFs varied considerably (ranging from 5970 µg L−1 to 10494 µg L−1 ). On average, about 40 volatile compounds were identified and quantified in the WSFs. Aromatics formed the bulk of the WSF of all of the crude oils, amounting to about 90% of the total VOCs. The WSF prepared from Raudatain crude oil contained the highest total VOCs (benzene and toluene) while that of Um-Ghadair contained the lowest. The WSF of Kuwait crude oil (export) was compared with that of individual oils and was found to contain relatively smaller amounts of individual components and the VOCs. Relatively higher amounts of toxic VOCs in the WSF of Raudatain crude oil has potential to impact the fona and flora as well as potable ground water in the area. Keywords: aromatics, comparison, composition, crude oils, Kuwait, volatile compounds, watersoluble fraction

1. Introduction Kuwait is one of the large producers and exporters of crude oil. Like other oilproducing countries, Kuwait produces oil from many geologically diverse oil fields. The chemical composition of the oils produced from each field is unique. The crude oil exported from Kuwait is a blend of many different oils. The composition of the blended oil (called Kuwait Crude Oil, Export) depends on the availability of the different crudes, process requirements, consumer specifications and other economical factors. Individual oils are not exported and as such are not considered as marine pollutants individually. However, in the 1991 Gulf War, the retreating Iraqi army used some of these oils from different oil fields to fill the trenches dug along the coast and the Kuwait-Saudi Arabian border to impede any possible attack and landing from the sea by setting the oil on fire. However, the plan could not be executed due to a hasty retreat. The fate of the oil in these trenches is largely unWater, Air, and Soil Pollution 120: 107–119, 2000. © 2000 Kluwer Academic Publishers. Printed in the Netherlands.

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known. Most of the trenches were covered up or the walls caved in and the oil was buried. Some the oil remained exposed and has weathered heavily. A significant part of the oil is known to have found its way to the coast and sea during the filling of the trenches and by seepage since the end of the war (Al-Hassan, 1992). During 1991, the retreating Iraqi army blew up about 800 wells in the Kuwaiti oil fields. A total of 616 wells caught fire while 76 wells were damaged and leaked oil but did not catch fire. Remaining well-heads were damaged but did not catch fire or leaked oil (Saeed et al., 1995). Soon after the clearing of mines and ammunition, efforts were launched to extinguish the oil fires. A massive amount of seawater was used to douse the flames in fire-fighting efforts. Seawater thus mixed freely with oil and seeped into the sandy soil of Kuwait desert taking with it compounds dissolved from the oil. The dissolved compounds threatened to pollute the fresh water aquifers in the northern Kuwait (Al-Sulaimi et al., 1993). Fresh ground water is a precious resource in Kuwait where there is no fresh surface water. The composition of the compounds that dissolve from crude oils in water has been the subject of many studies (Boylan and Tripp, 1971; Anderson, et al., 1974; Lee et al., 1974; Mackay and Shiu, 1976; Shiu, et al., 1990). These studies indicated that the water-soluble fraction (WSF) of crude oil was a complex mixture ranging from pentane to polycyclic aromatic hydrocarbons, phenols, nitrogen- and sulfur-containing heterocyclic compounds. The composition of the WSF depended on the composition of the oil, temperature, water-salinity and on the ratio of the volumes of water and oil that are brought into contact (Shiu et al., 1988). The toxicity of WSF was primarily due to the compounds that dissolve from oil into the aqueous phase. Aromatics were the main class of hydrocarbons found in WSF. Carls and Rice (1990) reported that mononuclear aromatics constitute about 89% of the total WSF. BTEX (benzene, toluene, ethylbenzene and xylenes) represented about 88% of the WSF. Many workers have investigated the composition of the WSF of Kuwait crude oil. Anderson et al. (1974) described the chemical composition. Murray et al. (1984) analyzed WSF of Kuwait crude oil by headspace and microextraction techniques. Ali et al. (1995) also reported the benzenoids and PAHs in the WSF of Kuwait crude oil. Recently, Saeed et al. (1998) investigated the composition of VOCs and PAHs in the WSF of Kuwait crude oil at different temperatures and in Arabian Gulf seawater (high salinity). However, there is no information available about the composition of the WSF of individual crude oils produced in Kuwait, which were spilled in the Kuwait desert by the retreating Iraqi army. The objective of the present study was to investigate the volatile compounds present in the watersoluble fraction of different crudes produced in Kuwait and compare it with the composition of the WSF of Kuwait crude oil (export) in seawater.

COMPOSITION OF WSFS OF KUWAITI CRUDES

109

Figure 1. Map showing the location of Kuwait’s onshore oil fields.

2. Materials and Methods There are ten major oil fields within the State of Kuwait (Figure 1) managed by Kuwait Oil Company (KOC). Authentic samples of crude oils were supplied by KOC. The samples were kept in airtight containers and stored in a freezer at – 20 ◦ C. The seawater used in the preparation was from an offshore intake well. The water was filtered through a series of filters to remove any biota and particulate matter and tested for the presence of any organic compounds. 2.1. P REPARATION

OF WATER - SOLUBLE FRACTION

The setup used for the preparation of WSF was that proposed by Ali et al. (1995). Figure 2 shows the schematic representation of the set up. It consisted of a 2-L bottle that was kept in a water bath. The temperature of the bath was controlled by circulating water from a water-chiller/heater circulator. The temperature of the

110


Figure 2. Schematic representation of the set-up used for the preparation of water-soluble fraction.

water-bath was monitored by a thermometer. The circulator controlled the set temperature to ±0.1 ◦ C. The water level in the bath was adjusted so that water and oil layers in the bottle were below the water level of the bath. The bath was placed on a magnetic stirrer. A Teflon-coated stirring bar (2 cm long) was placed in the bottle. The stirring speed was adjusted so as not to form a large vortex. The oil sample was introduced slowly on top of the water layer through a glass tube with the help of a syringe. The headspace was purged with nitrogen through another tube to expel air. WSF sample was collected by applying a slight nitrogen pressure that caused the WSF to rise in a glass delivery tube. The stirring was continued for 24 hr and the last sample taken. 2.2. P URGE

AND TRAP - GAS CHROMATOGRAPHIC ANALYSIS

The volatile compounds in the WSF were analyzed by purge and trap/GC using a flame ionization detector. Varian-3600 GC was linked to a Tekmar-3000 Purge and Trap Concentrator. A Tekmar cryofocusing module was employed to refocus the volatile desorbed from the trap. Data was acquired and reprocessed by Varian Star Chromatography Software. 3 mL sample of the WSF was introduced into the purging vessel with a Luer-lock syringe. A preset method (equivalent to EPA Method-502) was used for purging and trapping the volatiles. Briefly, the sample was purged for 11 min with helium. The purged volatile compounds were trapped on a Tenax trap. The trap was heated to 225 ◦ C to desorb and kept at the same


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temperature for 2 min during desorption. The desorbed compounds were refocused at the head of analytical column at –150 ◦ C after which the cryofocusing interface was heated to 180 ◦ C and the compounds introduced into the GC. The conditions for gas chromatographic analysis were as follows: Fused silica capillary column, coated with SPB-624 ( Supleco), 1.4 µm film thickness, 30 m long and 0.25 mm internal diameter. Helium was used as carrier gas at 2 mL min−1 . Initial column temperature was 40 ◦ C, maintained for 5 min and then programmed to 220 ◦ C at 4 ◦ min−1 . The final temperature was held for 10 min. Flame ionization detector used for detection. An external standard method was employed for quantitation. 2.3. P

AND

T/GC/MS

ANALYSIS

The identity of the peaks were ascertained by linking P and T/GC with MS. Tekmar3000 purge and trap concentrator was linked to Shimadzu GC-14A through a Tekmar cryofocusing module. GC was coupled with a Shimadzu QP-2000 quadruple mass spectrometer. The conditions used for GC analysis were same as given for P and T/GC. The mass spectra of unknown peaks were compared with those standards as well as with EPA/NIH mass spectral database.

3. Results and Discussions Kuwait oil fires were a major environmental catastrophe and required a large scale and intensive effort to control and put out raging fires. To provide water to extinguish fires, 361 water lagoons, each of 1 million-gallon capacity lined with plastic sheets were constructed. Water pipelines of 400 km with 150-km main feeding lines were assembled to deliver 20 million gallons of water per day to Kuwait well sites. It has been estimated that total water used in fire fighting was about 1.5 billion gallons (Hussain, 1995). The total oil spilled and eventually gathered in oil lakes was about 150 million barrels. Such a massive amount of seawater mixing with large amounts of crude oil carried an undetermined (but undoubtedly large) amount of organic compounds into the ground. In addition, during the occupation (August 1990–February 1991) the Iraqi army embarked upon an extensive effort to build defence and fortification lines that entirely encircled the State of Kuwait from the sea. These fortification lines included continuous lines of trenches that ran close and parallel to the coast. Crude oil was brought to the trenches by tanker trucks and through specially constructed pipeline that carried crude oil from the oil fields (Al-Hassan, 1992). At many places, the oil was allowed to overflow and/or leak into the surrounding coastal areas. At other places, oil pipeline was made to bleed directly into the sea (northern coast of Kuwait Bay) which contaminated ecologically important and biologically productive habitat in the coastal areas.

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TABLE I Levels (µg L−1 ) of volatile organic carbon compounds in the WSFs of different Kuwaiti crudes in seawater after 24 hr stirring Name

KCO

Burg

Ahmd

Magwa

Minag

Um-Gh

Abdli

Bahra

Sabriya

Raudtn

Ratga

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Methylcyclopentane Cyclohexane 3-Methylhexane Benzene n-Heptane Methylcyclohexane Octane isomer 1,3-Dimethyl cyclopentane Octane Isomer Toluene n-Octane Ethyl, methylcyclohexane Methylphenol Methylthiophane Ethyl benzene p + m-Xylene Dimethyl thiophane Dimethyl thiophane o-Xylene Cumene n-Propyl-benzene C3 -Benzene isomer Mesitylene

370 161 50 2391 3 37 79 23 3 2407 2 8 6 17 337 803 3 6 467 27 22 153 38

218 194 27 2146 0 36 97 21 2 2415 2 10 3 41 390 838 0 0 490 22 32 174 43

438 338 39 2868 0 59 169 27 6 3075 9 12 4 0 382 1051 0 0 596 28 32 185 52

358 31 41 2943 0 57 152 29 5 3016 2 12 3 3 385 1045 0 0 581 30 33 185 52

283 195 34 1978 0 67 93 28 5 2705 11 11 3 0 595 898 0 0 600 24 37 281 39

352 251 24 1787 13 21 93 25 2 1962 3 12 3 54 509 498 20 18 387 19 34 182 21

349 287 0 3188 0 56 145 27 8 3086 8 12 4 0 401 1014 0 0 635 29 32 179 49

232 207 30 2727 0 72 125 35 9 3014 12 14 5 0 421 1027 0 0 634 30 35 193 51

269 210 38 1987 0 59 107 30 6 2218 3 12 4 4 350 775 0 0 489 25 29 160 38

365 294 45 3524 0 70 147 29 7 3574 2 14 4 3 449 1174 0 0 713 33 37 206 57

366 260 40 2008 0 66 124 30 6 2313 10 11 4 0 374 837 0 0 585 21 27 184 39


Peak

TABLE I (continued) Name

24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43

C3 -Benzene isomer C3 -Benzene isomer 2-Methyl, propyl-benzene o-Cymene p-Cymene C3 -Benzene isomer Indane C4 -Benzene isomer 3-Propyl, 1-methylbenzene C4 -Benzene isomer n-Butylbenzene 1,2 Diethylbenzene C4 -Benzene isomer C4 -Benzene isomer C4 -Benzene isomer C4 -Benzene isomer 1-Methyl indane C4 -Benzene isomer 2-Methyl indane 4-Methyl indane

Total

KCO

Burg

Ahmd

Magwa

Minag

Um-Gh

Abdli

Bahra

Sabriya

Raudtn

Ratga

109 173 3 6 5 67 13 4 6 5 7 3 9 5 10 9 4 3 1 2

135 188 2 8 9 83 20 9 8 7 11 7 19 14 22 17 9 13 4 12

127 227 4 10 6 94 16 7 10 7 12 7 16 14 19 16 7 12 4 11

124 223 0 10 7 95 16 7 10 7 12 7 16 15 19 16 7 12 5 11

204 249 4 9 9 111 24 13 11 15 10 22 25 37 25 11 19 16 6 44

171 138 4 6 6 73 25 10 6 8 9 9 17 15 25 17 11 14 6 15

128 224 4 9 6 97 15 6 9 6 12 6 16 13 17 15 6 11 4 11

147 233 5 10 7 102 19 8 10 7 13 8 19 16 22 18 8 14 5 11

128 184 1 8 6 84 19 7 8 7 11 8 17 14 21 16 8 13 4 10

149 288 0 11 7 109 17 7 11 7 13 8 19 16 21 18 7 13 5 12

149 218 3 8 5 97 17 8 8 7 11 7 17 15 22 17 7 14 4 12

7858

7786

9987

9570

8706

6862

10115

9540

7376

11473

7940

113

KCO = Kuwait Crude Oil (Export), Burg = Burgan, Ahmd = Ahmadi, Mgwa = Magwa, Ming = Minagish, U-Gh = Um-Ghadair, Abdli = Abdalia, Bhra = Bahra, Sbrya = Sabriya, Rtdn = Raudatain, Rtga = Ratga.


Peak

114


Figure 3. Purge and trap/gas chromatogram of the WSF of Um-Ghadair crude oil in seawater.

Purge and trap/gas chromatographic analysis of the WSF of 10 different crude oils and Kuwait crude oil (export) after different stirring time indicated the presence of large numbers of volatile organic compounds. The results of the analysis are summarized in Table I. Qualitatively, the WSF of all of the oils was similar in major components, however, quantitatively, there were important differences especially with respect to minor components. Figure 3 shows the chromatogram of the WSF of Um-Ghadair crude oil as a typical example of the composition. The total amounts of VOCs in the WSF were variable. The total ranged from 1479 µg L−1 to 2228 µg L−1 after 2 hr of stirring while after 24 hr it ranged from 6862 µg L−1 to 11473 µg L−1 . The WSF of Um-Ghadair crude oil contained the lowest while that prepared from Raudatain crude oil contained the highest amount (67% more than Um-Ghadair). Kuwait crude oil (KCO) which is blend of different oil produced WSF that contained relatively lower amount of volatiles indicating that it is largely blended from crudes that produce WSF of low volatile contents. It is

115

COMPOSITION OF WSFS OF KUWAITI CRUDES 4000 3500 3000

ug/l

2500 Benzene 2000

Toluene

1500

C2-Benzene

1000

C3-Benzene C4-Benzene

Ratga

Raudatain

Sabriya

Bahra

Abdalia

Um-Ghadair

Minagish

Magwa

Burgan

Kuwait

0

Ahmadi

500

Figure 4. Graph showing comparative composition of aromatics in the WSFs of Kuwaiti crudes.

worth mentioning that the Burgan crude (the most productive oil field in Kuwait) produced WSF with relatively lower levels of volatiles. The range of compounds found in the WSF of different crudes was similar, from C6 -compounds to methyl indanes (C10 -compounds). About 43 volatile compounds were identified in most of the WSFs. Most of the compounds found were aromatic in nature (benzenoids). Some aliphatic compounds (ranging from C6 –C8 ) were detected but in low concentrations. Appreciable concentrations of naphthenic compounds were also present in all of the WSF. Heteroatom containing compounds (oxygen and sulfur) were present in the WSF of all crude oil though in low (but variable) concentrations. Benzene, an important compound from a toxicity point of view, was present in significant concentrations in the WSF of all crude oils. The relative concentration of benzene mirrored the total concentration of volatiles in the WSF i.e. its concentration was lower in the WSF of having the lower total volatile compounds. Consequently, WSF of Um-Ghadair and Sabriya crude oil produced WSF in which the concentration was relatively low as compared to Raudatain and Abdalia crude oils whose WSF contained relatively higher levels of benzene. After 24 hr of stirring, the level of benzene ranged from 1.8 mg L−1 to about 3.6 mg L−1 . Figure 4 shows the relative levels of benzene in the WSF of different crude oils. Toluene, another important compound in the WSF of crude oil, was present in slightly higher concentrations than benzene in almost all of the crude oils (the only exception being the WSF of Abdalia crude oil). The concentration ranged from 1962 µg L−1 (Um-Ghadair crude oil) to 3574 µg L−1 in the WSF of Raudatain crude oil after 24 hr stirring. The comparative levels of toluene can be seen in

116


Figure 4. The toluene levels for export crude oil were almost in the middle of the range and were similar to the levels found in the WSF of Burgan crude oil. The levels of ethylbenzene and xylenes displayed a similar range of variability as shown by benzene and toluene. Ethylbenzene levels varied from 350 µg L−1 (Sabriya crude oil) to 595 µg L−1 (Minagish crude oil). Xylenes (p- and m) also showed the same trend. The range of variability was wider in the WSF. Um-Ghadair crude oil WSF contained the lowest amount of xylenes (498 µg L−1 ) while Raudatain crude oil WSF was relatively rich in xylenes (1174 µg L−1 ). In general, the total of p- and m-xylenes was higher than that of ethylbenzene except in the case of Um-Ghadair crude oil where the level of xylenes in the WSF was lower than ethylbenzene. In the case of o-xylene, similar observations were made. The concentration of this compound ranged from 387 µg L−1 (Um-Ghadair crude oil) to 713 µg L−1 in the WSF of Raudatain crude oil. The relative levels of C2 -benzenoids can be seen more clearly in Figure 4. The WSF of all of the crude oils contained a rich variety of C3 -benzene compounds. At least 7 isomers were detected. Three of these isomers were identified while the rest could not be characterized from mass spectral data only. Like other compounds, the concentration of C3 -benzene isomers was also variable in the WSF of different crude oils. The range of variability of the total C3 -benzene isomers can be seen in Figure 4. The levels were lowest in Um-Ghadair and Sabriya crude oil WSF while in the WSF of Minagish and Raudatain crude oil the levels were relatively high. The levels of C3 -benzene in the WSF of Kuwait crude oil (export) were comparable to the crude whose WSF contained low levels of C3 -benzene. Figure 4 also shows the total of C4 -benzene isomers in the WSF of different crude oils. Although, the total number of isomers of C4 -benzene (at least 13 isomers) in the WSF of crude oil was much higher than C3 -benzene, the concentration was much less. Comparatively, Magwa and Minagish crude oil WSFs contained slightly higher amounts of C4 -benzene than those of other crude oils. The levels of C4 -benzene isomers were lowest in Kuwait crude oil (export). Table II shows a group summary of the composition of WSF of different crude oils. Aliphatics were relatively high in the WSF of Bahra, Raudatain and Ratga and lower for Um-Ghadair, Burgan, and Abdalia crude oil. The percentage contribution of aliphatics to the total volatile organic compounds was very low (ranged from 0.7 to 1.5%). Naphthenes were present in significant concentrations in the WSFs of all crude oils. The total was highest for Ahmadi crude oil and lower levels were found in the WSF prepared from Magwa crude oil. However, in terms of percentage, Um-Ghadair WSF contained higher percentage than any other crude oil WSF. The levels of heteroatom-containing compounds were generally very low except in Burgan and Um-Ghadair crude oil WSFs. In fact, the levels of these compounds were exceptionally high in the WSF of Um-Ghadair crude oil, mainly due to thiophane homologs. The total concentration of thiophanes in this sample was higher than the total for aliphatics. Consequently, the percentage contribution of these compounds

TABLE II Group summary of the volatile organic compounds in the WSF of different Kuwaiti crudes in seawater Group name

KCO

Burg

Ahmd

Mgwa

Ming

U-Gh

Abdli

Bhra

Sbrya

Rdtn

Rtga

(µg L−1 ) (µg L−1 ) (µg L−1 ) (µg L−1 )

95 643 7089 31

67 539 7136 44

113 985 8885 4

105 582 8877 7

116 611 7976 3

62 734 5970 96

72 821 9219 4

123 612 8800 5

106 627 6634 8

123 848 10494 7

122 791 7023 4

Aliphatics Naphthenes Aromatics Others

% % % %

1.2 8.2 90.2 0.4

0.9 6.9 91.7 0.6

1.1 9.9 89.0 0.0

1.1 6.1 92.8 0.1

1.3 7.0 91.6 0.1

0.9 10.7 87.0 1.4

0.7 8.1 91.1 0.0

1.3 6.4 92.2 0.1

1.4 8.5 90.0 0.1

1.1 7.4 91.5 0.1

1.5 10.0 88.5 0.1

Benzene Toluene C2 -benzenes C3 -benzenes C4 -benzenes

% % % % %

33.7 34.0 22.7 8.3 0.9

30.1 33.9 24.1 9.5 1.8

32.3 34.6 22.8 8.4 1.4

33.2 34.0 22.7 8.4 1.7

24.8 33.9 26.2 11.8 2.3

29.9 32.9 23.4 10.7 2.2

34.6 33.5 22.3 8.0 1.2

31.0 34.3 23.7 9.0 1.5

30.0 33.4 24.3 9.8 1.8

33.6 34.1 22.3 8.4 1.3

28.6 32.9 25.6 10.5 1.8


Total aliphatics Total naphthenes Total aromatics Total others

KCO = Kuwait Crude Oil (Export), Burg = Burgan, Ahmd = Ahmadi, Mgwa = Magwa, Ming = Minagish, U-Gh = Um-Ghadair, Abdli = Abdalia, Bhra = Bahra, Sbrya = Sabriya, Rtdn = Raudatain, Rtga = Ratga.

117

118


in the WSF of Um-Ghadair crude oil (1.4%) was higher than aliphatic compounds (0.9%). Aromatics formed the single largest group in the WSF of crude oils. The group largely consisted of BTEX, C3 -benzene and C4 -benzene compounds. The total concentration of aromatics in the WSF varied widely. The WSF prepared from Um-Ghadair crude oil contained only 5970 µg L−1 of total aromatics while that prepared from Abdalia crude oil contained as high as 10 494 µg L−1 aromatics. However, the variability of aromatics was considerably less when the percentage contribution of aromatics to the total volatile organic content of the WSF was considered. It ranged from 87% (Um-Ghadair) to 92.8% (Magwa). The comparative composition of aromatic subgroups in the WSF of these crude oils can also be seen in Table II. The relative contribution of benzene was lowest in the WSF of Minagish crude oil (24.8%) and was highest in the WSF of Abdalia crude oil (34.6%). The percentage of benzene was relatively high (33.7%) in the WSF of Kuwait crude oil (export). Toluene also showed similar a trend. However, the range of its contribution to the total VOCs in the WSF was much narrower (from 32.9 to 34.6%) as compared to the spread of benzene percentage in the WSF. The percentage of toluene was slightly higher than benzene in the WSF of all crude oils except in the case of the WSF of Abdalia crude oil in which case the benzene percentage was higher than toluene. C2 -benzenes formed another major subgroup of aromatics in the WSF. The percentage of this subgroup in total aromatics ranged from 22.3% (Raudatain) to 26.2% (Minagish). The percentage of the same in the WSF of Kuwait crude oil (export) was relatively low (22.7%). C3 -benzene subgroup, which was present in a much smaller concentration in the WSF, also varied from oil to oil. The percentage of this subgroup in the aromatics of the WSF ranged from 8.0% (Abdalia) to 11.8% (Minagish). Finally, C4 -benzene subgroup also varied in a similar way in the WSF of different crude oils. The percentage of C4 -benzenes in the aromatics in the WSFs varied from 1.2 to 2.3%. These results demonstrate the relative hazard potential of the water that mixed with different Kuwaiti crudes spilled in the desert. Kuwaiti desert soil is relatively poor and supports a little fona and flora under normal conditions. It can safely be assumed that the introduction of toxic compounds would have adversely impacted both fona and flora. It may be noted here that during 1991 oil fires, oil from Burgan, Magwa, Raudatain and Sabriya accounted for more than 90% of the oil spilled. Higher levels of VOCs in the WSF of Raudatian crude oil suggested that area covered with this crude oil would be more severely impacted. Furthermore, Raudatain and Sabriya areas are the most important locations for the production of potable ground water in Kuwait. The quality of ground water is expected to be impacted by the oil related pollutants in future (Al-Sulaimi et al., 1993).


119

Acknowledgements The partial funding for this study, provided by Kuwait Fund for Advancement of Sciences (KFAS), is gratefully acknowledged. The management of Kuwait Institute for Scientific Research (KISR) is also thanked for the rest of the funds.

References Al-Hassan, J. M.: 1992, The Iraqi Invasion of Kuwait, An Environmental Catastrophe, Khalid AlMarzouk Press, Kuwait, pp. 34. Ali, L. N., Fauzi, R., Mantoura, C. and Rowland, S. J.: 1995, Marine Environment Research 40, 1 Al-Sulaimi, J., Vishwanathan, M. V. and Szekely, F.: 1993, Environmental Geology 22, 246. Anderson, J. W., Neff, J. M., Cox, B. A., Tatem, H. E. and Hightower, G. M.: 1974, Marine Biology 27, 75. Boylan, C. C. and Tripp, B. W.: 1971, Nature 230, 44. Carls, M. G. and Rice, S. D.: 1990, Fishery Bulletin 88, 29. Hussain, T.: 1995, Kuwait Oil Fires: Regional Environmental Perspectives, Elsevier Science Ltd., pp. 67. Lee, C. C., Craig, W. K. and Smith, P. J.: 1974, Bulletin of Environmental Contamination and Toxicology 12, 212. Mackay, D. and Shiu, W. Y.: 1976, Bulletin of Environmental Contamination and Toxicology 15, 101. Murray, D. A. J., Lockhart, W. L. and Webster, G. R. B.: 1984, Oil and Petroleum Pollution 2, 39. Saeed, T., Al-Bloushi, A. and Al-Matrouk, K.: 1995, Archives of Environmental Contamination and Toxicology 29, 45. Saeed, T., Al-Mutairi, M., Ali, L. N., Al-Obaid, T. and Beg, M. U.: 1999, Accepted for publication in International Journal of Environmental Analytical Chemistry. Shui, W. Y., Bobra, M., Bobra, A. M., Maijanen, A., Sunito, L. and Mackay, D.: 1990, Oil and Chemical Pollution 7, 57. Shui, W. Y., Maijanen, A., Ng, A. L. Y. and Mackay, D.: 1988, Environmental Toxicology and Chemistry 7, 125.