FRESH OIL 



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44 d AMOCO-CADIZ MOUSSE 



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Figure 10. Gas chromotograms of aromatic fraction of light Arabian 

 crude oils and Amoco Cadiz mousse. 



mousse were observed at either site ifjata not shown). Table 8, shows 

 the effects of mousse additions on [2- C]-acetate oxidation to CO . 

 No' CH, was detected in any of the samples. At the unoiled control 

 site, the addition of 5% mousse decreased the amount of CO produced 

 in 2h by 70% (p = 0.02), while an 86% inhibition was observed with the 

 additions of 25% mousse (p = 0.01). At, the oiled site at lie Grande, 

 mousse additions appeared to inhibit CO production from [2- C]- 

 acetate although these differences were not significantly different 

 from the control (p ^ 0.25). 



The effect of fresh and slightly weathered light Arabian crude oil 

 on microbial activities in sediments was also examined because of the 

 probable chemical differences between the highly weathered mousse and 

 the oil which impacted the sites studied. The effect of 0.05% benzene 

 and toluene was also examined. They are highly volatile aromatic com- 

 pounds with known inhibitory effects (Robertson et al, 1973). Figure 9 

 shows chromatograms of the saturate fraction of the fresh and weathered 

 light Arabian crude. The fresh oil contained large amounts of low 



179 



