Trace metals in seawater and copepods in the ocean outfall area off the northern Taiwan coast

The concentration ranges of trace metals in the copepods, Temora turbinata, Oncaea venusta and Euchaeta rimana, near the outfall were: Cd, 0.23-1.81 μg g−1; Cr, 16.5-195 μg g−1; Cu, 14-160 μg g−1; Fe, 256-7255 μg g−1; Mn, 5.5-80.8 μg g−1; Pb, 2.6-56.2 μg g−1; Zn, 132-3891 μg g−1; and Al, 0.21-1.13%. Aluminum, and probably Fe, seemed to be the major elements in copepods. The concentrations of trace metals in copepods, especially Temora turbinata, near the outfall were generally higher than those obtained in the background station. The mean increase in bioconcentration factor of metals in copepods ranged from 4 to 7 and followed the sequence Al(6.4) > Cu(6.2) > Fe(6.0) > Zn(5.7) > Pb(5.6) > Cr(5.5) > Cd(5.1) > Mn(4.7). Therefore, marine copepods in the waters of northern Taiwan can accumulate trace metals over background concentrations and act as contamination indicators.