Proceedings - Teaching and Learning Centre - Simon Fraser ...

Fraser River Action Plan 3rd Research Workshop
General Conclusions
Session 1:
Pulp Mill Issues
Chair: C. Gray and J. Culp
• Chemical signals (i.e., organochlorine compounds like dioxins/furans) are reduced but still traceable in
bed and suspended sediments, in fish, and some aquatic-based wildlife, e.g., eagles, osprey, otters and
mink.
• Biological effects appear to be subtle or hidden, or we’re not looking at the right endpoints.
– looked at MFO in peamouth chub (Gibbon’s work complete), and Rocky Mountain whitefish
(Raymond’s work on-going); what does induction mean physiologically?
– there is a statistically significant depression in osprey productivity, particularly below Kamloops mill;
will this impact at the population level? Don’t know (Elliott’s work completed, but continue
embryo/egg sampling to determine impacts).
– there is measurable toxicity of three chlorophenols (guaicol, catechol, vanillin) to sturgeon (Farrell’s
work to be completed by next workshop).
– suspended sediments have a potential to moderate impacts of contaminants, as reflected by MFO
induction, from pulp mills (Parrot’s work to be completed by next year).
• Effects of nutrients in stimulating benthic community growth still unclear. It seems that
turbidity/suspended sediments may be great enough, during non-freshet periods, to inhibit growth.
Questions Raised:
Does benthic community enrichment lead to increased contaminant uptake, and therefore represent more
rapid transfer to fish? or,
Does an increase in benthic production create more biomass to dilute uptake? or,
In a eutrophic system are food chains just shorter resulting in less biomagnification?
• By virtue of capture success, peamouth chub represent the best, of several potential sentinel species, for
monitoring in the upper Fraser. Even though field data are limited, evidence suggests mill effluents are
capable of inducing physiological responses in lab and resident fish species (immature chub).
• With good loading estimates, the models can predict contaminants in both particulate and soluble
loading, as well as simulate effects of seasonal hydrology, temperature and suspended sediment
concentrations. The model will also plot changes in contaminant concentrations in fish as they age.
Discussion
Johnstone: A lot of comments on MFO induction. Are we down the wrong path?
Parrott: In general, I think MFO is a good indicator of exposure. The problem is extending it beyond
identifying that the fish were exposed recently. The relationship of a specific MFO level and a physiological
change has not been determined.
Hall: I understand that pulp mills add nutrients to their treatment systems whereas STPs are trying to remove
it. Why not get this together?
Gray: This is done in Quesnel ...
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