Biomarkers of Oxidative Stress and Persistent Organic Pollutants in Plasma and Eggs of Chelonia mydas Nesting in the Southern Gulf of Mexico

Abstract

The major nesting sites for the endangered green turtle (Chelonia mydas) are in Campeche, Mexico: Carmen, Isla Aguada, and Sabancuy. Although they are in a natural reserve, these nesting sites are threatened by agricultural activities and oil extraction. This study aimed to determine the presence and concentration of organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) in plasma and eggs and to assess the antioxidant response in plasma of nesting C. mydas from the southern Gulf of Mexico. Using censored statistics allowed us to do a realistic calculation incorporating the presence of non-detects in the analysis. A few contaminants (α+β+γ-HCH, trans-chlordane, 4,4′-DDE, 4,4′-DDT, methoxychlor, naphthalene, acenaphthylene, 2-Bromo naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, and dibenz[a,h]anthracene) were detected in plasma and their corresponding eggs, but correlations were not-significant. Spatial differences in concentrations of persistent organic pollutants (POPs) among nesting sites may reflect differences in foraging areas. Approximately 30% of the POPs in plasma and 60% of the POPs in eggs correlated with the biomarkers of oxidative stress. Detection of POPs in C. mydas indicated that plasma and eggs are suitable matrices to assess POPs concentrations.