Affiliations: Carl von Ossietzky University of Oldenburg, Institute
for Chemistry and Biology of the Marine Environment, Schleusenstr. 1, 26382
Wilhelmshaven, Germany | 1Johann Heinrich von Thuenen Institute, Federal
Research Institute for Rural Areas, Forestry and Fisheries Institute of
Agricultural Climate Research, Bundesallee 50, 38116 Braunschweig, Germany
Abstract: Bioassays employing the luminescent bacterium Vibrio fischeri
(LUMIStox system), the brine shrimp (Artemia salina) as well as the
acetylcholinesterase inhibition test were used to evaluate sediment toxicity of
surface sediments from five East Sumatra rivers. In March and November of 2008
samples were collected from Rokan, Siak, Kampar, Indragiri and Musi rivers from
overall 52 stations. The sediments were extracted with a sediment/water ratio
of 1:1 (w/v). The most toxic sediments were found at the stations 529 (Kampar),
543 (Musi) as well as 517 (Siak) during the November 2008 campaign. Of the
bioassays employed in this study, the acetylcholinesterase inhibition test was
the most responsive to the extracts (EC_{50}: 0.4 ± 0.1 to 1.02
± 0.3 g/L), whereas the invertebrate lethality assay using
Artemia salina was less sensitive (EC_{50}: 6.1 ± 0.6 to 9.3
±; 0.4 g/L). While it was not possible to correlate the observed
ecotoxicological effects with a specific and/or class of contaminants it is
notable that the Siak sediment extracts were consistently ranked the most toxic
with all test species and all test phases.
Keywords: Acetylcholinesterase inhibition, bioassay test systems, brine shrimp assay, LUMIStox, Sumatra river sediment, toxicity
