What are we studying? | Why are we studying? | What are we finding? | What does it mean? | Where can I read more?
What are we studying?
We study alligators (Alligator mississippiensis) in the ‘One’ environmental health approach to gain an overview of global health investigating the health of humans, wildlife, and ecosystem health. Alligators are large, and long-lived species that divide their time between water and land, including some marine environments. Thus, we use alligators as models to understand the threat of metal pollution to them, to monitor the health of the aquatic environment, and to understand human health. To accomplish this we employed several methods: 1) We collect alligator tissue samples to measure metal levels including chromium. 2) We establish primary cell lines to measure chromium induced cell death and genetic changes and compare those outcomes to the same endpoints in human and other wildlife species cell lines. 3) We measure DNA and chromosome damage in fresh alligator samples to determine if damage occurs in the individual and to monitor the population.
Why are we studying it?
Reptiles are among the first species to be affected by changes in the environment and so serve as an important study subject to monitor the health of the environment. Alligators may experience prolonged exposures to environmental contaminants such as chromium which is a ubiquitous global contaminant of aquatic environments primarily as a result of human activities. While chromium has been identified as a known human carcinogen, the health effects in alligators are poorly understood. Furthermore, metal levels have been previously investigated in alligators, but these studies are limited and the effects of these exposures remain to be determined. We aim to identify the risk of environmental contaminant to the alligator populations and determine if alligators can serve as indicators of the threat of environmental contaminants to human health.
What are we finding?
Our assessment of metals and DNA damage in the alligators is still underway and we do not have data to report. However, we have found in an initial study of alligator cell lines that both particulate and soluble forms of chromium(VI) induce cell death and damage chromosomes in alligator skin cells. These outcomes support the possibility that chromium may cause reproductive and developmental issues in the alligators and may cause alligator lung cancer.
What does it mean?
Our data support the suggestion that chromium(VI) poses a potential health risk to alligators who are exposed to it either through inhalation of chromium(VI) or other routes such as diet. Furthermore, because our data indicate that chromium damages chromosomes, chromium(VI) exposure may contribute to the development of cancer, developmental abnormalities and failure to reproduce.
Where can I read more?
- Wise, S.S., Wise, C.F., Xie, H., Wise, Jr., J.P., Guillette, Jr., L.J., and Wise, Sr., J.P. Hexavalent Chromium Is Cytotoxic and Genotoxic to American Alligator Cells. Aquatic Toxicology, 171, 30-36, 2016. PMID: 26730726. PMCID: PMC4721530.