Comparing the impacts of sediment-bound bifenthrin on aquatic macroinvertebrates in laboratory bioassays and field microcosms

Abstract

We conducted two laboratory bioassays and two field microcosm exposures with bifenthrin (a synthetic pyrethroid) in order to evaluate the capacity of single-species laboratory bioassays to predict lethal and sublethal impacts on aquatic invertebrates in microcosms. For the laboratory species, Chironomus tepperi, larval survival was reduced by 24% at 53.66 µg/g OC, while adult emergence was reduced at concentrations of 33.33 µg/g OC and higher, with a 61% decrease at 77.78 µg/g OC and no emergence at 126.67 µg/g OC. The abundance of several other microcosm taxa was reduced in the microcosms at a similar concentration range (33.33 µg/g OC and above), however there was no impact on the abundanc..