THE ROLE OF THE ZEBRA MUSSEL, DREISSENA-POLYMORPHA, IN CONTAMINANT CYCLING .1. THE EFFECT OF BODY-SIZE AND LIPID-CONTENT ON THE BIOCONCENTRATION OF PCBS AND PAHS
Ka. Bruner et al., THE ROLE OF THE ZEBRA MUSSEL, DREISSENA-POLYMORPHA, IN CONTAMINANT CYCLING .1. THE EFFECT OF BODY-SIZE AND LIPID-CONTENT ON THE BIOCONCENTRATION OF PCBS AND PAHS, Journal of Great Lakes research, 20(4), 1994, pp. 725-734
The zebra mussel, Dreissena polymorpha, a recent invader to the Great
Lakes, may influence contaminant cycling by bioconcentrating high leve
ls of hydrophobic contaminants in its tissue. To better understand zeb
ra mussel bioconcentration and ultimately, contaminant cycling, we mea
sured bioconcentration factors (BCFs) and kinetic parameters for accum
ulation of polychlorinated biphenyl and polycyclic aromatic hydrocarbo
n congeners for two size classes of mussels and for a pre-spawning (hi
gh lipid) and post-spawning (low lipid) mussel population. High lipid,
pre-spawning mussels had greater BCFs and faster uptake kinetics for
the highly hydrophobic compounds, i.e, hexachlorobiphenyl and benzo(a)
pyrene, than the low lipid, post-spawning mussels. BCFs and uptake kin
etics determined for the less hydrophobic compounds, i.e., tetrachloro
biphenyl and pyrene, were not measurably influenced by differences in
lipid content. Small mussels (15 mm shell length) had higher BCFs and
faster uptake kinetics for all compounds compared to larger (21 mm she
ll length) mussels. Contaminant elimination was not affected by size o
r differences in lipid levels. For both lipid levels rand size classes
of mussels, the BCFs were positively correlated with compound log oct
anol:water partition coefficient. Hence, the lipid affinity of a compo
und can be a good indicator of mussel contaminant accumulation Potenti
ally large contaminant concentration in zebra mussels may alter contam
inant cycling in the Great Lakes by increasing contaminant transfer to
mussel predators. Selective predation on small, pre-spawning (high li
pid) mussels may present a greater hazard to predators than predation
on larger, post-spawning (low lipid) mussels.