Colloque

Chemicals in eels captured in the St. Lawrence Estuary

P.V. Hodson

R. McLeod

M. Castonguay

E. Pelletier

C. Desjardins

C.M. Couillard

Membre a labase

P.V. Hodson

Résumé du colloque

We measured chemicals in American eels purchased in 1990 from fishermen in Kamouraska, Cacouna (s. shore) and Saint-Irénée (n. shore), and sampled from a shore tributary (controls). Eels from Kamouraska contained more PCBs, mirex and pesticides than controls but no more than eels from the other sites. Mercury did not vary among sites, and PAHs, dioxins and furans were usually undetectable and well below guidelines. Levels of PCBs and mirex have declined by 68 and 56% respectively since 1982, with only 36% exceeding guidelines for PCBs, compared to 80% in 1982; for mirex, the percentage was 52% in 1982 and 29% in 1990. Pesticides also declined, except dieldrin, unchanged since 1982. Chemical levels were correlated to eel weight within weeks, but not among weeks, suggesting a mixing of groups with different levels of contamination. However, we could not statistically discriminate stocks based on pesticides or PCB congeners. The tissue distribution of chemicals mirrored lipid distribution and showed that analyses of carcasses are suitable for monitoring contamination. The risk of toxicity to Belugas from consuming eels is declining.