Evaluating decline parameters of rotiferBrachionus plicatilispopulations as an interstitial water toxicity bioassay

✍ Scribed by T.A. DelValls; L.M. Lubián; M. González; J.M. Forja

• Book ID: 104614562
• Publisher: Springer
• Year: 1996
• Tongue: English
• Weight: 678 KB
• Volume: 341
• Category: Article
• ISSN: 1573-5141
• DOI: 10.1007/bf00018119

✦ Synopsis

Population decline of the rotifer Brachionus plicatilis has been evaluated as a sensitive and reliable bioassay for assessing toxicity of marine sediment interstitial water . Three environmental conditions were examined using both interstitial and seawater cultures : (a) adverse effects from dissolved contaminant concentrations ; (b) effects from particulate organic matter ; and (c) increase or decrease of bacterial biomass from addition of mixtures of antibiotics . Three different parameters were measured to characterize decline : (i) time required for 50% of inoculated population to die (TLS0) ; (ii) curve of the decline rate of Brachionus plicatilis (ABP) ; and (iii) graphical area contained below plot of the egg :female ratio curve against time (ABP) . Results indicated that, for each of the different assays, the three parameters of the Brachionus plicatilis population decline test were sensitive to concentrations of contaminants dissolved in interstitial waters (principally : total ammonia, Cu, Cr and alkylbenzenesulphonates) but not to particulate organic matter . Nevertheless, the presence or absence of mixed antibiotics with the contaminants may influence the Brachionus plicatilis population decline test, principally by retarding the hatching of eggs . Based on these results, Brachionus plicatilis is confirmed as an appropriate organism for use as an indicator of interstitial water contamination, using either decline rate, TL50 or both parameters . The presence of particulate matter has no effect on these parameters, but the bacterial population may be an influence, although to a lesser extent than the toxicants .