A culture-based assessment of the effects of chlorpyrifos on multiple meiobenthic copepods using microcosms of intact estuarine sediments

摘要

Meiobenthos occur at densities of ＞10~6/m~2 in almost every uncontaminated estuarine sediment of the world, yet few studies have explored their utility for a multiple-species chronic bioassay of sediment contaminant effects. A new approach using laboratory-reared, whole-sediment meiobenthic microcosms was developed to holistically test the sublethal effects of chlorpyrifos on benthic copepod survival, age structure, and reproduction. Entire sediment-dwelling meiofaunal communities from a pristine estuarine preserve were cultured (I.e., net population gains were achieved in controls) for at least a full generation to the known 96-h copepod adult 15/100 lethal concentration and larval 50/100 lethal concentration of sediment-associated chlorpyrifos (21-33 μg/kg sediment).