Using Plasma Vitellogenin in Loggerhead Sea Turtles to Assess Reproductive Maturation and Estrogen‐Like Contaminant Exposure Environmental Toxicology and Chemistry

Vitellogenin (VTG), an egg yolk precursor, is abnormally produced by male and juvenile oviparous species after exposure to estrogens. Plasma VTG in loggerhead sea turtles ( Caretta caretta ) helped us understand their reproductive maturation and investigate it as a bi omarker of contaminant exposure. The presence of VTG was screened in plasma from 404 loggerheads from the northwestern Atlantic Ocean using a freshwater turtle antibody inwestern blots. The concentra tions of VTG were semiquanti fied using band intensities calibrated to results from a log- gerhead antibody enzyme ‐linked immunoassay. The detection and conce ntrations of VTG were in (from highest to lowest): nesting females, in ‐water adult females, subadult females, smaller females, unknown sex, and males. Logger- heads from this region begin vitellogenesis at ≅77 cm straight carapace length. We classi fied VTG expression as ab- Grant no. NA03NMF4720281