vel (NOEC) determined in the stage studied. We cannot rely on specific dose-response curves to define the safe exposure limits of methyl mercury, we need to approach its toxicity with a more holistic perspective.
             To illustrate this alternative approach, we will look at methyl mercury and its potential impact on one generation of coho salmon, Oncorhyncus kisutch. We will be looking at the literature as it relates to each stage in the lifecycle of O. kisutch, determine where potential impacts exist through its ecology, and then use this information to develop a more accurate study in which to assess the exposure limits of methyl mercury. The lifecycle stages of O. kisutch that will be addressed include embryonic, fry, and juvenile and maturing adults, and the source of methyl mercury will be bottom sediment pollution by a pulp mill effluent in the near shore environment.
             The effects of methyl mercury are most pronounced during the embryonic stage, and can be potentiated by an initial risk of exposure from parental females. The concentration of methyl mercury found in eggs has been found to be equivalent to that of the parent females (Hemmerschmidt et al, 1999), causing the eggs to be at risk of exposure before fertilization, depending on the exposure history of the adult females. Eggs of the Killfish, Crenichthys baileyi, exposed to a methyl mercury concentration of 1.0 ppm exhibited a 30% fertility rate vs. 90% in the control (Khan, 1986), and of those that were fertilized, 32% of the embryos exhibited abnormalities. The embryos of O. kisutch have exhibited a significant inhibition of growth and development when exposed to a methyl mercury concentration of 0.62 ppm (Devlin, Muttet, 1992), and hatchlings derived from contaminated eggs also exhibited a toxic response to methyl mercury. Eggs of the brook trout, Salvelinus fontinalis, when ex!
             posed to a methyl mercury concentration of 2.2 ppm, produced hatchlings that
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