Relationship Between Mixed Function Oxygenase Induction and Other Health Parameters for Fish Exposed to Bleached Kraft Mill Effluent, 1993 Environmental Conference Proceedings

Monitoring the effects of industrial wastes in receiving waters includes monitoring the responses of fish. Fish are present in most surface waters and their welfare is relevant to the public, to environmental control, and to sports and commercial fisheries.

The measurement of the activity of fish liver detoxication enzymes, the mixed function oxygenases (MFO), has been proposed as a tool for monitoring the environmental effects of bleached kraft mill effluent (BKME) discharges.

Field research programs in Scandinavia and North America have demonstrated hat the activity of MFO in fish reflect exposure to chemical inducers associated with effluent from pulp mills using chlorine bleaching. Induction of activity appeared to be correlated with important effects on fish and fish populations. However, there are continuing questions regarding the use of MFO activities as an indicator of biological effects. Recent studies in Western Canadian rivers have shown no relationship between MFO induction and reproductive growth or disease parameters in fish. Further experimental work comparing known exposures with effects in fish is needed.