Precision and Sensitivity of a Seven-Day Growth and Survival Toxicity Test Using the West Coast Marine Mysid Crustacean Holmesimysis Costata

Abstract

Abstract-A 7-d growth and survival toxicity test using the west coast marine mysid crustacean Holmesimysis costata (Holmes) was evaluated to determine test precision and sensitivity. The intralaboratory coefficient of variation (CV) among six reference toxicant test median lethal concentrations (LC50s) was 25%, whereas the mean intralaboratory CV for side-by-side effluent test LC50s was 7%. The mean intralaboratory CV for the concentration at which growth was inhibited by 25% (IC25) was 19%. Interlaboratory CVs for effluent LC50s averaged 14%, whereas variation among growth IC25s averaged 15%. Test precision and sensitivity compared favorably with literature values for a number of commonly used toxicity tests and chemical methods. Toxicity increased slightly with increased mysid exposure from 4 to 7 d (mean effluent LC50s of 9.9% for 4 d of exposure and 7.5% for 7 d), and more significantly from 7 to 24 d (zinc LC50 values were 50 g/L and 7.8 g/L for concurrent 7-d and 24-d tests). Although growth was a less sensitive endpoint than survival in tests with individual chemicals (zinc and sodium azide), growth was the more sensitive endpoint in seven of nine tests with complex effluents. Seventy-five percent of tests conducted at all participating laboratories met protocol test acceptability criteria (n ϭ 40).

Acute and chronic toxicity of nickel to marine organisms: Implications for water quality criteria

“…Five endpoints were measured in the 28-d chronic mysid test, and the most sensitive of these was survival. As com-monly occurs with mysid tests [6,17], survival fluctuated in the lower concentrations before dropping precipitously at higher concentrations (Fig. 3).…”

“…The mean length of exposed mysids was significantly lower than that in controls only at the highest concentration tested (83.6 μg/L), and no significant reductions in mysid weight were observed at any test concentration (analysis of variance, p = 0.53). Growth endpoints are often less sensitive than survival in mysid tests, especially with trace‐metal toxicants [17]. This is often because the few mysids surviving at higher concentrations are relatively large, either because larger mysids are more tolerant or because surviving mysids enjoy the nutritional benefits of cannibalism.…”

Cadmium, lead and their mixtures with copper: Paracentrotus lividus embryotoxicity assessment, prediction, and offspring quality evaluation

“…It could be hypothesized that the Pb concentration (from 0.016 to 20.5 lg/l-UNEP 1996; Manfra and Accornero 2005) in the Southern Tyrrhenian seawater, where the sea urchin P. lividus lives and was collected for this study, probably together with other contaminants had build up the tolerance of the species to a series of toxicants including Pb with could have inducted a high level of tolerance (Hunt et al 1997;King and Riddle 2001;Pavicic et al 1994) on sea urchin gametes. This underlines a limit on the utilization of organisms collected in a population in a natural habitat.…”

Interlaboratory evaluation of Hyalella azteca and Chironomus tentans short-term and long-term sediment toxicity tests

“…Other studies have shown both marine and freshwater amphipod tests to be reliable and reproducible with spiked or diluted sediment samples [19,[33][34][35][36][37]. In an interlaboratory study of the 10-d marine amphipod (Eohaustorius estuarius) survival test conducted by seven laboratories using four sediments, Bay et al [37] reported strong agreement among laboratories for ranking which sediment samples were toxic.…”