Petroleum hydrocarbons in sediments from Jeddah Coast of Saudi Red Sea following the 1996 fuel oil spill

Abstract EN

The average concentration of extractable organic matter (EOM) in the sediments of the study area decreases in the order of Jeddah oil refinery > King Faisal Navy Base > Al-Salam lagoon / Islamic Seaport.

The concentration of petroleum hydrocarbons in the sediments being in the range of (0.9 to 281, mean 42.7 µg g1 dry wt) and (3.9 to 34, mean 12 µg g1 dry wt) for regions I and II respectively.

The highest recorded value was found at the oil refinery zone.

The distribution of the aliphatic hydrocarbons of region I showed that the n-alkenes between C14 and C33 are present with great variability in the intensity.

The input of recent oil was relatively substantiated by the presence of the n-alkenes (medium molecular weights).

The contribution of the biogenic hydrocarbons (fatty acids) was also noticed in most of the samples analyzed.

An Unresolved Complex Mixture (UCM) is present with great variability in the samples from same region.

The oil residue of station 12 (oil refinery zone) was highly weathered, reflecting the absence of volatile components and most of the nalkenes.

The UCM signals of Jeddah oil refinery zone (e.g.

station 12) was very high resulting from chronic oil pollution.

The distribution of n-alkenes in the second region differs considerably from the first region of the study area probably due to influence of microbial degradation.

The presence of the fatty acid in relatively high intensity compared with n-alkenes, indicates that the contribution from the natural source is significant in this region.

Also, a homologues of alkenes in a relatively high quantity, in one of the extracts, is also reported from the second region only.

Its presence in a series has not been observed previously.

This ongoing project is to characterize and identify these compounds.