International Journal of Marine Science 2016, Vol.6, No.48, 1-10
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Table (1) Regional concentration of polycyclic aromatic hydrocarbons (ng/g)dry weight in soil of west Qurna -2 oil field during
summer season 2015.
PAHs compounds
Station1
2
3
4
5
6
7
8
9
10
Naphthalene
0.014
0.014
0.018
0.013
0.042
0.051
0.012
0.011
0.019
0.019
Acenaphthylene
0.018
0.032
0.045
0.051
0.040
0.064
0.075
0.111
0.090
0.213
Acenaphene
0.028
0.055
0.057
0.020
0.055
0.025
0.042
0.03
0.045
0.127
Fluorene
0.052
0.114
0.087
0.179
0.230
0.088
0.191
0.171
0.202
0.293
Phenanthrene
0.038
0.053
0.051
0.088
0.124
0.066
0.085
0.094
0.106
0.486
Anthracene
0.006
0.086
0.014
0.110
0.057
0.050
0.080
0.014
0.08
0.232
Fluoranthene
0.021
0.04
0.036
0.063
0.083
0.057
0.072
0.076
0.106
0.127
Pyrene
0.064
0.196
0.229
0.043
0.141
0.095
0.256
0.092
0.288
0.480
Benzo(a)anthracene
0.054
0.059
0.063
0.065
0.11
0.049
0.066
0.096
0.094
0.105
Chrysene
0.003
0.005
0.017
0.01
0.037
0.048
0.024
0.066
0.037
0.015
Benzo(b)fluoranthene
0.005
0.014
0.008
0.036
0.013
0.014
0.011
0.015
0.021
0.013
Benzo(k)fluoranthene
0.008
0.010
0.016
0.018
0.028
0.019
0.021
0.032
0.038
0.051
Benzo(a)pyrene
0.022
0.031
0.054
0.049
0.144
0.187
0.116
0.239
0.103
0.087
Carbazole
0.018
0.049
0.059
0.048
0.088
0.112
0.249
0.145
0.216
0.098
Indo(1,2,3-cd)pyrene
0.003
0.007
0.008
0.013
0.025
0.061
0.024
0.075
0.052
0.012
Dibenzo anthracene
0.020
0.021
0.037
0.031
0.043
0.053
0.035
0.080
0.052
0.040
Benzo(g,h,i)perylene
0.004
0.021
0.02
0.015
0.026
0.057
0.02
0.170
0.023
0.040
Total
0.378
0.807
0.819
0.852
1.286
1.096
1.379
1.517
1.572
2.438
Fluoranthen/Pyrene
0.328
0.204
0.157
1.465
0.588
0.6
0.281
0.826
0.368
0.264
Phen/Ant
6.333
0.616
3.642
0.8
2.175
1.32
1.062
6.714
1.325
2.094
LMW/HMW
0.880
0.953
0.602
1.597
0.963
0.576
0.677
0.501
0.701
1.590
Ant/(Ant+Phen)
0.136
0.618
0.215
0.555
0.314
0.431
0.484
0.129
0.430
0.323
BaA/(BaA+Chry)
0.947
0.921
0.787
0.866
0.748
0.505
0.733
0.592
0.717
0.875
InP/(InP+BghiP)
0.428
0.25
0.285
0.464
0.490
0.516
0.545
0.306
0.693
0.230
In all stations along the period of study we observed that HMW-PAHs were more than LMW-PAHs, this may be
attributed to the molecular weight. Differences in degradation processes in both low and high molecular weight
PAHs was because of wide group of microorganisms including fungi, algae and bacteria. In any case, bacteria play
the most important role in completion of mineralization. Lower molecular weight PAHs such as naphthalene and
phenanthrene degrade rapidly, but higher molecular weight PAHs such as pyrene, fluoranthene, benzo(a)
anthracene and benzo(a)pyrene are more recalcitrant (Bakhtiari et al.,2009; Obayori and Salam, 2010). In
expansion to that the low molecular weight PAHs such as naphthalene has the highest vapor pressure of PAHs.
Therefore volatilization in environments is probably the most important removal mechanism for these compounds
(USEPA, 1982).
The results of regional PAHs at the present study showed a highest concentration of PAHs was in winter at station
10 (9.966 ng/g dry weigh) and the lowest in summer at station 1 (0.378 ng/g to dry weigh), while the higher mean
concentration of PAHs in station 10 (5.906 ng/g) and the lowest in station 1(1.125 ng/g) (Table 5).
Variation in the recorded concentrations of the PAHs was observer during the study. They gradually increased
starting from station 1 until station 5, and then significantly decreased at station 6 and then increased to station 10.
The fluctuation in concentrations of PAHs in stations is due to distance from the flame of the flare which near to
the stations 8,9,10 and far to the stations 1,2,3,4,5,6,7.
