The Great Lakes Indian Fish and Wildlife Commission (GLIFWC) has produced Ogaa (walleye-Sander vitreus) consumption advisories since 1996 for Anishinaabe from GLIFWC member tribes in the 1837 and 1842 ceded territories of Wisconsin. GLIFWC's advisory maps were revised in 2005 to address cultural sensitivities (to protect tribal lifeways), to utilize recent mercury exposure information, and to incorporate changes in advisory levels for methyl mercury. Lake-specific, risk-based, culturally sensitive consumption advice was provided on color-coded maps for two groups: children under age 15 years and females of childbearing age, and males 15 years and older and females beyond childbearing age. The maps were distributed to, and a behavioral intervention program developed for, the six GLIFWC member tribes in Wisconsin as well as member tribes in Minnesota and the 1842 ceded territory of Michigan. Tribal fish harvesters, tribal health care providers, women of childbearing age or with young children, tribal leaders, elders, and children were targeted specifically for the behavioral intervention. The efficacy of the behavioral intervention was assessed using surveys of 275 tribal fish harvesters from Wisconsin, 139 tribal harvesters from Michigan and Minnesota, and 156 Wisconsin women of childbearing age. Significant increases in the percentage of survey participants who indicated awareness of advisory maps occurred among Wisconsin harvesters (increase from 60% to 77%), Michigan and Minnesota harvesters (29% to 51%), and women of childbearing age in Wisconsin (40% to 87%). A significant increase in preference for smaller Ogaa occurred among tribal harvesters in Wisconsin (41% to 72%) and tribal harvesters in Michigan and Minnesota (49% to 71%), although not among women of childbearing age. The GLIFWC map-based advisory program did not adversely affect tribal harvest of Ogaa, which increased from 63,000 to 88,000 fish in the three states after the intervention.

The toxicity of a series of 21 mono- and dihalogenated aliphatic monoesters has been evaluated using a Tetrahymena pyriformis population growth impairment assay. A structure-activity model has been developed for toxicity data (log(IGC50(-1))), using the 1-octanol/water partition coefficient (logKow) and the energy of the lowest unoccupied molecular orbital (ELUMO) as descriptors. A statistically robust plane (log of the inverse of the 50% growth inhibitory concentration (IGC50(-1)) = 0.34logKow - 0.84 (ELUMO) + 0.04; n = 15, r2 = 0.85, s = 0.26, F = 33, Pr > F = 0.0001) was found for monohalogen-substituted derivatives. These substances are thought to exhibit toxicity via the soft electrophilic mode of toxic action. This toxicity is imparted by the leaving ability of the halogen, which is enhanced when it is placed in close proximity to the carbonyl group. This leaving ability allows haloesters, especially alpha-haloesters, to undergo an SN2, addition-elimination substitution electro(nucleo)philic reaction. Outliers to the above model broadly fell into two groups: small reactive molecules (e.g., propylbromoacetate) that were more toxic than predicted and molecules in which the reactive center was sterically hindered by an alkyl group (e.g., ethyl-2-bromoisovalerate), which were less toxic than predicted.

The Great Lakes Indian Fish and Wildlife Commission produces consumption advisories for methylmercury in walleye (Sander vitreus) harvested by its member tribes in the 1837 and 1842 ceded territories of Michigan, Minnesota, and Wisconsin, USA. Lake-specific advice is based primarily on regressions of methylmercury concentrations on walleye length and incorporates standard reference doses to generate recommended meal frequencies. The effects of variability and uncertainty are directly incorporated into the consumption advice through confidence bounds for the general population and prediction bounds for the sensitive population. Advice is tailored to the needs of the tribes because harvest and consumption of fish are culturally important. Data were sufficient to provide consumption advice for 293 of the 449 lakes assessed. Most of these carried a recommendation of no more than 4 meals per month for the general population and no more than 1 meal per month for the sensitive population.

The toxicity of a series of 21 mono- and dihalogenated aliphatic monoesters has been evaluated using a Tetrahymena pyriformis population growth impairment assay. A structure-activity model has been developed for toxicity data (log(IGC50(-1))), using the 1-octanol/water partition coefficient (logKow) and the energy of the lowest unoccupied molecular orbital (ELUMO) as descriptors. A statistically robust plane (log of the inverse of the 50% growth inhibitory concentration (IGC50(-1)) = 0.34logKow - 0.84 (ELUMO) + 0.04; n = 15, r2 = 0.85, s = 0.26, F = 33, Pr > F = 0.0001) was found for monohalogen-substituted derivatives. These substances are thought to exhibit toxicity via the soft electrophilic mode of toxic action. This toxicity is imparted by the leaving ability of the halogen, which is enhanced when it is placed in close proximity to the carbonyl group. This leaving ability allows haloesters, especially alpha-haloesters, to undergo an SN2, addition-elimination substitution electro(nucleo)philic reaction. Outliers to the above model broadly fell into two groups: small reactive molecules (e.g., propylbromoacetate) that were more toxic than predicted and molecules in which the reactive center was sterically hindered by an alkyl group (e.g., ethyl-2-bromoisovalerate), which were less toxic than predicted.

The Great Lakes Indian Fish and Wildlife Commission has an extensive program to inform Anishinaabe tribal members from northern Wisconsin, Michigan, and Minnesota who harvest and consume walleye about the health risks of consuming these fish, and to encourage harvest and consumption practices that reduce exposure to MeHg. We report here the results of a probabilistic analysis of exposure to methyl mercury (MeHg) among tribal members who consume walleye. The model predicts that the potential for greatest exposures to MeHg occur among women of child-bearing age and children who consume large walleye from lakes that contain heavily contaminated (MeHg concentration >0.5 mg/kg) fish. The analysis allows GLIFWC to evaluate, focus, and fine-tune its initiatives to protect the health of tribal members in ways that result in exposure and risk reduction for tribal harvesters, women of child-bearing age, and children, while maintaining important tribal lifeways, which include the harvest and consumption of walleye.