Abstract

Monitoring the health effects of environmental contaminants such as heavy metals can be achieved using sentinel species as models and a means for establishing baseline comparison data. Reptiles are among the first species to be affected by changes in the environment and so serve as an applicable study subject.¹ Leatherback sea turtles (Dermochelys coriacea) are an endangered marine species that may experience prolonged exposures to environmental contaminants such as hexavalent chromium referred to as Cr(VI). Cr(VI) is a ubiquitous global contaminant of the marine environment as a result of human activities. While Cr(VI) has been identified as a known human carcinogen, the health effects in marine species are poorly understood. Metal levels have been previously investigated in sea turtle species, but the effects of exposures remain to be determined.^2-4 In this study, we assessed the cytotoxic and genotoxic effects of particulate and soluble Cr(VI) in leatherback sea turtle lung cells and compared these results with data in human lung cells. Both particulate and soluble Cr(VI) induced a concentration-dependent increase in cytotoxicity that was comparable to experiments in human lung cells. We have shown Cr(VI) is clastogenic to human lung cells. Therefore, using a chromosome aberration assay, we assessed the genotoxic effects of Cr(VI) in leatherback sea turtles. Particulate and soluble Cr(VI) induced a concentration-dependent increase in clastogenicity. These data indicate that Cr(VI) may be a health concern for leatherback sea turtles and other long-lived marine species. Additionally, the data indicate leatherback sea turtles can serve as a model species for monitoring the health effects of Cr(VI) in the environment and therefore serve as an indicator species for environmental human exposures.

Acknowledgements

The authors would like to acknowledge Christy Gianios, Jr. for information technology support, respectively. We would also like to thank the staff of the Vieques Conservation and Historical Trust, TICATOVE, and the Vieques Office of the United States Fish and Wildlife Service for their support for this work. Research reported in this publication was also supported by the National Institute of Environmental Health Sciences of the National Institutes of Health under Award Number R01ES016893 (JPW). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Additional funding was provided by the Maine Space Grant Consortium (JPW), The Ocean Foundation (JPW), the Henry Foundation (JPW), the Curtis and Edith Munson Foundation (JPW), and the Maine Center for Toxicology and Environmental Health.

* Presenting author
+ Student presenter

Literature Cited

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