Benthic foraminifera are used as potential bio-indicators of pollution due
to the “Erika” oil spill. The foraminiferal assemblages from a site situated on the
tidal mudflat of the southern Bay of Bourgneuf (Vendée, France) have
been sampled 19 times on a monthly/bimonthly scale. The field study reveals
uncommon low densities and poor faunas in the first 21 months of the survey.
In order to understand the effect of the “Erika” fuel, foraminiferal cultures with
0 to 72.0 mg per 100 ml of “Erika” oil were maintained in controlled conditions in
the laboratory. In the laboratory, an experiment with 5.5 mg per 100 ml of
oil shows morphological abnormalities, cellular modifications and a low rate
of reproduction. These first results confirm the potential toxicity of the
fuel No. 2 from “Erika” and the sensitivity of foraminifera to this pollutant.