The weathering of petroleum was monitored by high temperature high resolution gas-liquid chromatography in northern Brittany seashore sediments, either contaminated by the Amoco Cadiz oil or experimentally polluted. Most aliphatic and aromatic hydrocarbons were relatively rapidly degraded, but some compounds like isoprenoids (pristane and phytane), triterpanes and alkylated phenanthrenes and dibenzothiophenes appeared to be more recalcitrant. In high energy sites (Roscoff beach), cleaning of the sediments was achieved between 12 and 18 months, whereas the Abers muddy sediments contained after two years bacterially neosynthesised very long chain n-alkanes (>n-C50). Interaction between physical leaching and biodegradation was responsible for sediments... |