Abstract |
In a preliminary test with Uca minax and U. pugilator exposed to PCBs in mud (1.04 micrograms PCBs/g) and a mud-sand mixture (0.37 micrograms PCBs/g), both species attained apparent steady state concentrations within 14 days, yielding calculated bioaccumulation factors (BAF) that ranged from 0.19 to 1.07. A definitive test with U. pugilator exposed to similar PCB concentrations in sediment produced BAF values from 0.44 to 0.71; however, the predicted time to 90% steady state ranged from 20 to 58 days. These tests demonstrate that fiddler crabs can accumulate PCBs from weathered sediments to concentrations that approximate the exposure concentrations and thus could distribute PCBs into aquatic, avian, and mammalian food webs in saltmarsh ecosystems. |