• One health toxicology: expanding perspectives and methods to assess environmental contaminants

      Harley, John Robinson; O'Hara, Todd; Dunlap, Kriya; Duffy, Lawrence; Rea, Lorrie (2017-12)
      The discipline of One Health is founded on the principal that environmental health, animal health, and human health are interconnected. Although the field has been largely focused on zoonotic diseases, examining concepts such as toxicology under a One Health lens can offer a more holistic and preventative approach to research and implementation and, in particular, how fish-based diets may be involved with One Health outcomes. Here we present three general case studies that demonstrate new approaches to investigating One Health toxicology. In Chapter One we show how Arctic canids can be used as environmental sentinels for human health. We discuss three separate canid studies; in the first we find that Arctic foxes can act as sentinels of Arctic contaminants due to their foraging plasticity, in the second we examine the use of fish-fed sled dogs as a model for the effects of a fish-based diet on contaminants exposure and gene transcription, and in the third we develop the sled dog as a model for particulate matter air pollution in the Fairbanks North Star Borough. In Chapter Two we utilize the Steller sea lion, a nonmodel organism, as a sentinel for the effects of fish-based diet mercury exposure induced whole-genome changes in gene transcription (RNA-Seq). Using newly developed informatics tools we assemble a de novo transcriptome and examine large scale changes in gene expression related to mercury exposure and other One Health uses. This approach is extremely adaptable and has the potential to be applied across numerous non-model organisms and contaminants. We also applied a microbial mining algorithm to our RNA-Seq data and found evidence for a hemotropic Mycoplasma spp. in one of our samples. In Chapter Three we examine sources of mercury exposure for pregnant women from La Paz, Baja California Sur, Mexico. We found mercury concentrations to be generally low among the examined fish species and staple foods. While typical dietary assessments rely on recall surveys and questionnaires, we found that examining chemical biomarkers of diet including stable isotopes of carbon and nitrogen are critical in dietary risk assessment. Taken together these three investigations offer valuable lessons and techniques which can be applied to the field of One Health toxicology; especially to those fish diet based systems.
    • The Northway Wild Food And Health Project: Confronting The Legacy Of Toxic Waste Along The Alcan

      Godduhn, Anna R.; Duffy, Lawrence K. (2011)
      Northway, Alaska is a small, mostly Athabascan community with a large Formerly Used Defense Site, located near the Alaska Highway in Eastern Interior Alaska. Despite remediation in the 1990s, local residents are concerned about the contamination of wild foods. This Community Based Participatory Research project comprised two studies: the Northway Wild Food Study, to investigate contaminant levels in locally prioritized traditional foods; and the Northway Health Study, to investigate locally suspected links between historic pollution sources and health problems. The project identifies multiple pathways of exposure that were more significant in the past, including a clear water creek, whitefish, a pipeline corridor, and a public water tank. Historic contamination with petroleum, persistent organic pollutants, the ingredients of Agent Orange, and chlorinated byproducts of disinfection, respectively, is neither well documented nor quantifiable. Retrospective cohort comparisons of historic resource users to non-users found complex associations. Reported users of these resources showed a higher reported incidence of several health conditions, including cancer, thyroid-, reproductive-, and metabolic problems, and cardiac irregularities. This thesis postulates that the situation represents a case study of endocrine disruption via multiple unquantifiable and interactive pathways, including myriad unknowns that preclude the establishment of "cause and effect" relationships. Complex emerging phenomena present particularly intractable sources of uncertainty, in this case including the lifelong effects of low dose toxic exposure during development. However, community based research has the capacity to improve local and scientific understanding of the repercussions of environmental pollution in rural communities that are still grappling with the legacy of military waste.