Preliminary results of planktonic copepod, Acartia omorii as biomarker for environmental toxicity

Abstract

Zooplankton is an important component of the food webs of marine and brackish ecosystems. Copepod zooplankton is very abundant and plays as a mediator between phytoplankton and small fish in the food webs. Ecotoxicological risk to zooplankton is evaluated by the biomarker approach, can be used as an early warning signal of risk to the health of marine ecosystems. We conducted two experiments to estimate the toxicity of benzo[a]pyrene and pore water on a copepod species Acartia omorii (i) effects of benzo[a]pyrene on DNA single strand breakage and (ii) toxicity of pore water on mortality. DNA damage was observed in homogenates of whole organisms. DNA strand breakage in individual cells increased with addition of benzo[a]pyrene. It was similar to H2O2 using as positive control. Pore water was extracted from bottom sediments of Gwangyang Bay, which is located in the southern part of Korea. In all sampling sites, the mortality of the copepod increased with addition of pore water, and the response of copepod to pore water was significantly different among the sampling sites. It might be related to the concentrations of organic pollutants in sediments. This study suggests that Acartia omorii can be used as a biomarker for monitoring of environmental pollution1