Wild rodents (Dipodomys merriami) used as biomonitors in contaminated mining sites

Abstract

Mining is one of the most important industrial activities globally; however, mining processes have critical environmental impacts, as mining is a major source of metals and metalloids that contribute significantly to the pollution of soil, sediment, water and air. Heavy metals can impact the health of exposed human populations and nonhuman receptors. This study focused on arsenic because its genotoxicity is well-known. Previously, we proposed a methodology to evaluate and integrate risk from a single source affecting different biologic receptors. Here, we propose an alternative approach estimating arsenic exposure in children and kangaroo rats using probabilistic simulation with Monte Carlo modeling. The estimates are then associated to measured DNA damage and compared to both populations of children and rodents living in contaminated and in reference areas. Finally, based on the integrated analysis of the generated information, we evaluate the potential use of wild rodents (Dipodomys merriami) as a biomonitor at mining sites. Results indicate that the variation of genotoxicity in children of the reference site is ≈ 2 units when compared to the children of the contaminated site. In the rodents we observed a variation of ≈ 4 units between those of the reference site when compared to those living on the contaminated site. We propose that D. merriami can be used as a biomonitor organism in sites with mining activity, and that a non-lethal test can be used to evaluate risk from metal exposure.

Keywords:

• Dipodomys merriami
• biomonitor
• children
• arsenic
• Monte Carlo

Acknowledgments

This work was supported by a grant from the National Institute of Ecology, SEMARNAT (2004-01-9-0238) and the Universidad Autónoma de San Luis Potosí (C07-FAI-11-2.38). We would also like to thank Dr. D.R.J. Moore for commenting on the manuscript. We also thank Biol. Susan Quackenbush for English language editing of the manuscript. This study was conducted with a Scientific Collector's Permit (Colector Científico de Flora y Fauna Silvestre) issued through SEMARNAT (No. FAUT-0133). The studies involving humans were conducted in accordance with national and institutional health guidelines for the protection of human subjects.

Notes

^†Indicate significant difference in relation to exposure dose on contaminated area (p < 0.001).

* Indicate significant difference in relation to exposure dose on contaminated area (p < 0.001).