title: Comparison of two wild rodent species as sentinels of environmental contamination by mine tailings.
abstract: BACKGROUND
  Contamination with heavy metals is among the most hazardous environmental concerns caused by mining activity. A valuable tool for monitoring these effects is the use of sentinel organisms. Particularly, small mammals living inside mine tailings are an excellent study system because their analysis represents a realistic approach of mixtures and concentrations of metal exposure.
  
  
  OBJECTIVE
  We analyzed metal tissue concentrations and DNA damage levels for comparison between genders of a sentinel (Peromyscus melanophrys) and a nonsentinel (Baiomys musculus) species. Also, the relationship between DNA damage and the distance from the contamination source was evaluated.
  
  
  METHODS
  This study was conducted in an abandoned mine tailing at Morelos, Mexico. Thirty-six individuals from both species at the exposed and reference sites were sampled. Metal concentrations in bone and liver of both species were analyzed by atomic absorption spectrophotometry, and DNA damage levels were assayed using the alkaline comet assay.
  
  
  RESULTS
  In general, concentrations of zinc, nickel, iron, and manganese were statistically higher in exposed individuals. A significant effect of the organ and the site on all metal tissue concentrations was detected. Significant DNA damage levels were registered in the exposed group, being higher in B. musculus. Females registered higher DNA damage levels than males. A negative relationship between distance from the mine tailing and DNA damage in B. musculus was observed.
  
  
  CONCLUSIONS
  We consider that B. musculus is a suitable species to assess environmental quality, especially for bioaccumulable pollutants--such as metals--and recommend that it may be considered as a sentinel species.
authors.affiliation: Departamento de Sistemática y Evolución, Centro de Investigación en Biodiversidad y Conservación, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico.
authors.forename: E
authors.initials: E
authors.lastname: Tovar-Sánchez
authors.forename: L T
authors.initials: LT
authors.lastname: Cervantes
authors.forename: C
authors.initials: C
authors.lastname: Martínez
authors.forename: E
authors.initials: E
authors.lastname: Rojas
authors.forename: M
authors.initials: M
authors.lastname: Valverde
authors.forename: M L
authors.initials: ML
authors.lastname: Ortiz-Hernández
authors.forename: P
authors.initials: P
authors.lastname: Mussali-Galante
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000737:chemistry; D002470:Cell Survival; D004249:DNA Damage; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods*; D005260:Female; D008099:Liver / Q000737:chemistry; D008297:Male; D019216:Metals, Heavy / Q000032:analysis*; D008800:Mexico; D008906:Mining; D010542:Peromyscus / Q000502:physiology; D012377:Rodentia / Q000502:physiology*
chemical_list: D019216:Metals, Heavy