Development and Application of a Marine Sediment Pore-Water Toxicity Test Using Ulva Fasciata Zoospores

Abstract

Abstract-An acute (96 h) pore-water toxicity test protocol using germination and growth of Ulva fasciata zoospores as endpoints was developed to test the toxicity of marine and estuarine sediment pore-water samples. Tests with an organic toxicant (sodium dodecyl sulfate; SDS), three metals (Cd, Cu, and Zn), and ammonia (NH 3 ) were conducted to determine zoospore sensitivity. Zoospore germination and gametophyte growth were as sensitive to SDS as sea urchin (Arbacia punctulata) fertilization and embryological development. Zoospore sensitivity to metals was greater than or comparable to that of adult macroalgae. Zoospores were less sensitive to NH 3 than were other commonly used toxicity test organisms. Test results using this algal assay with sediment pore-water samples with high NH 3 concentrations were compared with results from sea urchin fertilization and embryological development tests for the same samples. Ulva fasciata zoospore germination was not affected by samples with high NH 3 concentrations that were toxic in both sea urchin tests. Zoospore tolerance of NH 3 and sensitivity to other contaminants indicate that their response may be useful in toxicity identification evaluation studies with pore-water samples that contain high concentrations of unionized NH 3 .

Metal Bioavailability and Toxicity in Sediments

“…Ammonia is frequently present in sediments and may confound determinations of sediment toxicity. A method for marine and estuarine pore water testing using a marine algae, Ulva fasciata, has been demonstrated (Hooten & Carr, 1998). This algae is unaffected by high ammonia concentrations and therefore is useful in TIE studies where bioassays using ammonia sensitive bioassays (e.g., sea urchin fertilization and embryological development) are used simultaneously.…”

Reappraisal of the toxicity test method using the green alga Ulva pertusa Kjellman (Chlorophyta)

“…0.095-0.326 mg l -1 for sporulation, 0.189-0.200 mg l -1 for gametophyte growth (length and cell no., respectively), 0.789 mg l -1 for germination [1,2,13], but it is lower as compared with that reported for U. fasciata (1.930 mg l -1 for germination) [14]. The EC50 values (with 95% CI) of Cu toxicity obtained from the new method were 0.144 (0.110-0.162) mg l -1 which is less sensitive than some other parameters reported in the same species (0.050-0.100 mg l -1 for growth, 0.023-0.027 mg l -1 for gametophyte growth, 0.017 mg l -1 for germination) [3].…”

Effects of Metals and Organic Contaminants on the Recovery of Bioluminescence in the Marine Dinoflagellate Pyrocystis Lunula (Dinophyceae)1

“…Micrographs were taken on a Nikon Optiphot-2 at a magnification of 20 ϫ using differential interference contrast optics (Nomarski) and Fuji Velvia slide film (50 ASA). Scale bar, 50 m. , Hooten and Carr 1998, Kraus et al 1998, Langdon et al 1996, Lussier et al 1999, Nalecz-Jawecki et al 1997, Villegas-Navarro et al 1999. Phenanthrene has been used as a model substance to study the bio-logical degradation of polycyclic aromatic hydrocarbons by marine microorganisms (Cullen et al 1994, Cuny et al 1999, Hayes et al 1999.…”