Culturally adapted mobile technology improves environmental health literacy in Laurentian,Great Lakes Native Americans (Anishinaabeg)

The presence of persistent bioaccumulative toxics (PBT) in aquatic food chains complicates decision processes of people with a strong culture of fish consumption. This environmental contamination is especially problematic for Native American populations in the Laurentian Great Lakes region (Anishinaabeg). Pursuing the growing discipline of environmental health literacy (EHL) may help reduce toxic exposures, support healthy decision-making, and combat health deficits. Our goals for this research were first to improve environmental health literacy using novel technologies and second to help define environmental health literacy metrics that can be tracked over time, especially regarding culturally-contextualized health interests. We recently reported that a mobile app (Gigiigoo'inaan App) presenting personalized, culturally-contextualized fish consumption advice may improve EHL for the Anishinaabeg. Gigiigoo'inaan App safely supports desired fish consumption rates by putting local data into the hands of the Anishinaabeg. We conducted a pre-test post-test evaluation with 103 Aninishinaabe adults. Participants estimated their current fish meal consumption over a hypothetical month before exposure to the software and then planned their future consumption of fish meals in a month after using the mobile app. Significantly more monthly traditional fish meals on average (Median: 4 vs 2, p = 0.0005) were selected when using the app versus pre-exposure to the app. Significantly more traditional grams of fish were also selected during use of the app relative to the pretest (Median: 680.39 g vs 453.59 g, p = 0.0007). These increases were accompanied by widespread (97%) adherence to conventional advice that minimizes PBT exposure health effects (ATSDR minimum risk levels).     

Is it safe to eat fish from the Great Lakes? An adaptive modelling-monitoring framework to assess compliance with consumption advisories

In this study, we conducted a retrospective analysis of the spatio-temporal trends of fish contamination in the Canadian Great Lakes. We subsequently formulated consumption advisories that explicitly account for all sources of uncertainty, such as model error, sampling bias, and natural variability of fish assemblages. Our analysis generated exceedance frequency maps of the tolerable daily intakes (TDIs), which showed that mercury (Hg) concentrations are generally at a safer level for consumption, whilst polychlorinated biphenyls (PCBs) continue to result in restrictive advisories. Specifically, the initial decline in PCBs has transitioned into a steady state, possibly due to the combined effects of external contamination sources and internal abiotic and biotic factors. Our assessment of the PCB decline rates required to comply with TDI thresholds over the next twenty years suggest that a small degree of reduction is needed for Walleye (Sander vitreus) across all sampled sites, whereas much faster decay rates are needed for Lake Trout (Salvelinus namaycush), especially in lower Lake Huron, Lake Erie, and Lake Ontario. We also detected a distinct Hg gradient whereby the southernmost waterbody, Lake Erie, had the lowest average concentrations, whereas the highest levels amongst the fish species sampled were registered in St. Lawrence River. Finally, we show the ability of our Bayesian approach to fish consumption advisories to produce time-specific, highly customizable, risk-assessment statements that account for the inherent variability in natural fish communities and the variant degree of empirical evidence about the contamination history in different locations around the Great Lakes.     

Significance of toxaphene in Great Lakes fish consumption advisories

Fish consumption advisories have been issued for the Great Lakes generally based on the most restrictive contaminant. For the Canadian waters of the Great Lakes, toxaphene causes minor restrictions only in Lake Superior, i.e., 3% of the total (restrictive + unrestrictive) advisories issued. However, the significance of the hazard posed by toxaphene in fish is not clear since more restrictive advisories due to other priority contaminants may be masking the less restrictive advisories. We simulated fish consumption advisories for the Toxaphene-only scenario by neglecting the presence of contaminants other than toxaphene, and compared with the issued advisories as well as with the published simulated Mercury-only scenario. Restrictive advisories under the Toxaphene-only scenario compared to the issued toxaphene related advisories would increase from 3% to 14%, < 1% to 4%, and 0% to 2% for Lakes Superior, Huron and Ontario, respectively, and remain at 0% for Lake Erie. For Lake Superior, most of the restrictive Toxaphene-only advisories would be for fatty fish. Overall, the Toxaphene-only advisories would be significantly less restrictive compared to the issued advisories, and also generally less restrictive compared to the Mercury-only scenario. These results suggest that toxaphene is less of a concern than PCBs (including dioxin-like PCBs), dioxins–furans and mercury from the perspective of health risk to humans consuming Great Lakes fish; elevated toxaphene is mainly a concern for human consumers of Lake Superior fatty fish. Our results suggest that the routine monitoring of toxaphene in other Canadian waters of the Great Lakes and Lake Superior lean/pan fish could be discontinued.     

Fatty acids in ten species of fish commonly consumed by the Anishinaabe of the upper Great Lakes

The Chippewa Ottawa Resource Authority (CORA) in Sault Ste. Marie, Michigan, has been monitoring contaminant concentrations in the fillet portions of fish from the 1836 treaty-ceded waters of lakes Superior, Huron, and Michigan since 1991. The goal is to provide up to date consumption advice for their CORA member tribes. For the first time since the program started, CORA has included fatty acid analysis in 2016 monitoring of fish in Lake Superior. Ten species were targeted by CORA based on 25 years of experience and regular discussions with Anishinaabe fish consumers. This paper reports these results and presents some preliminary discussion of the consequences for consumption advice for the CORA member tribes who inhabit the Great Lakes region. Six of the species were sampled from Lake Huron and Lake Superior and four were sampled from supermarkets. Wild caught fish are an important link to the culture of Great Lakes Native American tribes and important sources of food and omega-3 polyunsaturated fatty acids (PUFA N-3). While some PUFA N-3 data from the Great Lakes is available, this dataset provides an important supplement and is specific to the 1836-treaty ceded waters of CORA. This paper confirms the presence of PUFA N-3s in Great Lakes fish traditionally harvested by the CORA tribes.     

A Bayesian assessment of the PCB temporal trends in Lake Erie fish communities

The temporal trends of polychlorinated biphenyls (PCBs) in Lake Erie fish were evaluated using 30 years of fish contaminant data (1977–2007). The first step of our statistical analysis was based on simple exponential decay models parameterized with Bayesian inference techniques to assess the declining rates in four intensively sampled fish species, i.e., walleye (Stizostedion vitreum), coho salmon (Oncorhynchus kisutch), rainbow trout (Oncorhynchus mykiss) and white bass (Morone chrysops). Because the exponential model postulates monotonic decrease of the PCB levels, we included first- or second-order random error terms in our statistical formulations to accommodate non-monotonic patterns in the dataset studied. Generally, our results suggest that the PCBs have been decreasing over the last 30 years with relatively weak rates that vary among the different fish species examined. Yet, our analysis with the exponential decay model also identified an increasing trend in the PCB concentrations of walleye skinless–boneless filet data, which is manifested after the mid-90s. In the second step, we used dynamic linear modeling (DLM) analysis to account for the fact that the fish length covaries with the PCB concentrations and that different sized fish may have been sampled over time. Our DLM analysis suggests that the previously reported trend of the walleye filet data is actually an artifact associated with the bias of the fish sampling practices followed. The coho salmon and rainbow trout PCB concentrations have been decreasing steadily during the study period but the associated rates were relatively weak. Finally, the PCB trends in white bass appear to have been stabilized over that last decade, although the robustness of this result remains to be confirmed due to the temporal inconsistencies of the information used. We conclude by emphasizing the importance of explicitly accounting for the different covariates (e.g., length, age, lipid content) that can potentially hamper the detection of the actual temporal trends of fish contaminants.