Ho K T, Kuhn A, Pelletier M, McGee F, Burgess R M, Serbst J
U.S. Environmental Protection Agency, 27 Tarzwell Drive, Narragansett, Rhode Island 02882, USA.
Arch Environ Contam Toxicol. 2000 Nov;39(4):462-8. doi: 10.1007/s002440010128.
Standard methods of sediment toxicity testing are fairly well accepted; however, as with all else, evolution of these methods is inevitable. We compared a standard ASTM 10-day amphipod toxicity testing method with smaller, 48- and 96-h test methods using very toxic and reference sediments. In addition we compared parallel exposures of single species, either the amphipod Ampelisca abdita or the mysid Americamysis bahia, to multiple species, mysid, and amphipod, cohabiting the same types of chambers. These comparisons were performed for both water-only and sediment-water tests. Results of the comparison of the standard ASTM 10-day amphipod test with the smaller, 48- and 96-h test chambers indicate that survival was high in both test designs using the reference sediment. With toxic sediments, complete mortality occurred in less than 48 h using the smaller experimental chambers and only after 96 h in the larger experimental chambers. We concluded that although time to death is shorter in the smaller, shorter exposure chambers, there was no overall change in mortality for the organisms, and that the smaller chambers were predictive of the results obtained with larger chambers and longer exposures. For multiple species testing in whole sediment exposures there was no change in toxicity to either the amphipod or the mysid when they cohabited the same chamber. In contrast, for water-only exposures, A. bahia demonstrated less sensitivity when cohabiting the same chamber as A. abdita. Therefore, during whole sediment testing we can add A. bahia and A. abdita to the same test chamber without changing the toxicity to either species; however, in our 10-ml water-only exposures, the species should be tested separately.
沉积物毒性测试的标准方法已得到相当广泛的认可；然而，与其他所有事物一样，这些方法的演变是不可避免的。我们使用剧毒沉积物和参比沉积物，将美国材料与试验协会（ASTM）的标准10天双壳纲动物毒性测试方法与更短的48小时和96小时测试方法进行了比较。此外，我们还比较了单物种（双壳纲动物Ampelisca abdita或糠虾Americamysis bahia）的平行暴露与同处相同类型试验箱中的多物种（糠虾和双壳纲动物）的平行暴露。这些比较在仅水暴露试验和沉积物 - 水暴露试验中均进行了。将标准ASTM 10天双壳纲动物试验与更短的48小时和96小时试验箱进行比较的结果表明，在使用参比沉积物的两种试验设计中，存活率都很高。对于有毒沉积物，使用较小的试验箱时，不到48小时就出现了完全死亡，而在较大的试验箱中，仅在96小时后才出现完全死亡。我们得出的结论是，虽然在较小的、暴露时间较短的试验箱中死亡时间较短，但对于生物来说死亡率没有总体变化，并且较小的试验箱能够预测在较大试验箱中以及较长暴露时间下获得的结果。对于全沉积物暴露中的多物种测试，当糠虾和双壳纲动物同处一个试验箱时，对它们任何一方的毒性都没有变化。相比之下，对于仅水暴露试验，当与A. abdita同处一个试验箱时，A. bahia的敏感性较低。因此，在全沉积物测试期间，我们可以将A. bahia和A. abdita添加到同一个试验箱中，而不会改变对任何一个物种的毒性；然而，在我们10毫升的仅水暴露试验中，这两个物种应该分开测试。
