PARENT SESSION
IP03 - Biomonitoring
Chair: Allen, Joel1, 1 PO Box 310559, Denton, TX
Co-chair: Lazorchak, Jim2, 2 US EPA, Cincinnati, OH
2:10 PM to 5:30 PM - Sunday, 17 November 2002
Room Room 150 G
(IP18) The burrowing mayfly Hexagenia limbata as a metal biomonitor in northern Quebec rivers.
Michaud, Annick*,1, Masson, Stéphane1, Hare, Landis1, Campbell, Peter G.C.1, 1 Université du Québec, Sainte-Foy, Quebec, Canada
ABSTRACT- Trace metals such as Cd, Cu and Zn are major contaminants of lakes and rivers in metal mining regions of Quebec. Although measurements of total metals in sediment or water have been used to estimate the degree of environmental contamination in such regions, such measurements do not take into account the availability of metals to organisms. In contrast, metal measurements in animals integrate the diversity of processes that influence metal bioavailability. We sampled two northern Quebec rivers for candidate biomonitors. Nymphs of the mayfly Hexagenia limbata were found to be good biomonitors for several metals due to their large population densities, wide distribution, large body size and tolerance to metals. Concentrations of Cd, Cu, Cr, Ni and Pb varied widely in H. limbata both among sites within a river and between rivers. The fact that nymph Cu concentrations varied widely among sites suggests that this insect does not regulate this essential metal at the whole animal level. In contrast, the essential metal Zn appears to be regulated by nymphs. Because Cd and Cu concentrations in H. limbata showed inverse trends in the two rivers, future work will include transplantation of nymphs between the two rivers to measure the exchange rates of these metals
Key words: Hexagenia limbata, river, metals, biomonitor