PARENT SESSION

2K - Sediment Assays
Poster Hall
8:30 AM - Tuesday, 29 April 2003

(TUP/140) Comparison of liquid phase and whole sediment bioassays to characterise dredging material from Spanish ports.

DelValls, T. A.¹, Casado-Martinez, M.C.¹, Buceta, J. L.², Iacondini, A.³, Riba, I.¹, Blasco, J.⁴, Forja, J.M.¹, ¹ Facultad de Ciencias del Mar y Ambientales. Universidad de Cádiz, Puerto Real, Cádiz, Spain² Centro de Estudios y Experimentación de obras Públicas (CEDEX), Madrid, Madrid, Spain³ Centro Interdepartamentale di recerca per le scienze ambientali (CIRSA). Università degli Studi di Bologna., Ravenna, Bologna, Italy⁴ Instituto de Ciencias Marinas de Andalucía, Puerto Real, Cádiz, Sapin

ABSTRACT- Ports and harbours are good sedimentation basins and dredging processes are essential for construction of the water-based infrastructure and to maintain navigation in ports, harbours and inland waterways. Contaminants bound to sediments to be dredged can affect organisms both through the whole sediments and through the liquid phase exposure. Different liquid phase test were used in order to evaluate the toxicity of dissolved and suspended contaminants from dredging materials on organisms. These kind of bioassays can be used both using pore water or elutriates. Here, liquid phase was obtained following standard operational procedures to elutriate (it is defined as the process of equilibrating a volume of sediment with a volume of diluent for a specified period of time, after which the diluent is separated by settling, filtration or centrifugation and are designed to simulate release of contaminants from a sediment during dredged material disposal). Ideally, the organisms should be representative of appropriately sensitive water column species existing in the vicinity of the disposal site. In order to compare the toxic response on different organisms exposed to the liquid phase from dredged materials from Spain and to evaluate the adverse effects on the water column, we collected different samples from three Spanish Ports. The rotifer population decay bioassay using the specie Brachionus plicatilis and the Microtox^® test following the Standard Operational Procedure in liquid phase were performed. Results were compared to those from different solid phase bioassays (Microtox^® Basic Solid Phase Protocol and 10d bioassay using amphipods from the specie Ampelisca brevicornis) and to the chemical analysis results from the whole material and from the elutriates.

Key words: Microtox^®, elutriate, Brachionus plicatilis