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Snakes as Novel Biomarkers of Mercury Contamination: A Review

  • David L. HaskinsEmail author
  • Robert M. GogalJr.
  • Tracey D. Tuberville
Part of the Reviews of Environmental Contamination and Toxicology book series


Mercury (Hg) is an environmental contaminant that has been reported in many wildlife species worldwide. The organic form of Hg bioaccumulates in higher trophic levels, and thus, long-lived predators are at risk for higher Hg exposure. Although ecological risk assessments for contaminants such as Hg include pertinent receptor species, snakes are rarely considered, despite their high trophic status and potential to accumulate high levels of Hg. Our current knowledge of these reptiles suggests that snakes may be useful novel biomarkers to monitor contaminated environments. The few available studies show that snakes can bioaccumulate significant amounts of Hg. However, little is known about the role of snakes in Hg transport in the environment or the individual-level effects of Hg exposure in this group of reptiles. This is a major concern, as snakes often serve as important prey for a variety of taxa within ecosystems (including humans). In this review, we compiled and analyzed the results of over 30 studies to discuss the impact of Hg on snakes, specifically sources of exposure, bioaccumulation, health consequences, and specific scientific knowledge gaps regarding these moderate to high trophic predators.


Agkistrodon piscivorus Anthropogenic contamination Aquatic Bioaccumulation Biomagnification Biomarker Colubridae Ecological risk assessment Ecotoxicology Heavy metal Immunotoxicology Maternal transfer Mercury Mercury pollution Metal toxicity Nerodia sipedon North America Northern watersnake Predator Receptor species Reptile Serpent Snake Terrestrial Toxicology 



Preparation of this manuscript was supported by an assistantship through the University of Georgia’s Interdisciplinary Toxicology Program and the Savannah River Ecology Laboratory, as well as the Department of Energy under award number DE-EM0004391 to the University of Georgia Research Foundation and by the Savannah River Nuclear Solutions – Area Completions Project.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • David L. Haskins
    • 1
    • 2
    • 3
    Email author
  • Robert M. GogalJr.
    • 4
  • Tracey D. Tuberville
    • 1
  1. 1.Savannah River Ecology LaboratoryUniversity of GeorgiaAikenUSA
  2. 2.Interdisciplinary Toxicology ProgramUniversity of GeorgiaAthensUSA
  3. 3.Warnell School of Forestry and Natural Resources, University of GeorgiaAthensUSA
  4. 4.Department of Biosciences and Diagnostic ImagingCollege of Veterinary Medicine, University of GeorgiaAthensUSA

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