Estimating environmental exposures for tribes engaged in traditional subsistence lifestyles

Most tribes have goals of restoring resources and regaining healthier and more traditional lifestyles and diets. Subsistence practices that place members in more intense environmental contact may result in increased health risk. Identification of hazardous agents and knowledge about how people become exposed can be of great value for self-protection, for pollution prevention, and for remediation. However, risk assessments need to be designed and scaled appropriately to be inclusive of the range of factors that may impact the exposure. Ethno-historical, nutritional, ecological, and biomedical methods have been combined in the development of subsistence exposure scenarios in tribal settings, including: (1) fish ingestion rates--current fish ingestion rate are higher than the general population, but are lower than original subsistence (Treaty-based) rates; (2) reconstruction of original diets--use of ethno-historical, nutritional, and other lines of evidence are combined with ecological descriptions; (3) soil ingestion rates--comparison of suburban studies and studies applicable to indigenous settings is presented, with conclusions about appropriate soil ingestion rates; and (4) uptake of contaminants by native plants—pilot results of uptake of environmental contaminants in cattails are described, considering the uses of various parts of the plant throughout the year. The values underscoring this research are likely to become increasingly important in dealing with global environmental issues that transcend geographic boundaries and impact diverse population groups. Because these scenarios describe how resources are used in traditional subsistence manners, they are also useful in restoration planning and health promotion activities.

This research was funded by the Environmental Protection Agency, EPA-STAR-J1-R831046.