Monitoring toxic organochlorine (OC) compounds is important in wildlife, especiallyin protected species such as sea turtles. Blood offers many benefits for monitoring OCs. it can be collected non-destructively from live turtles and can be sampled repeatedly for continuous monitoring. OC concentrations in blood better represent the exposure levels of target tissues, but blood concentrations may fluctuate more than those in fatty tissues following recent dietaryexposure or lipid mobilization. The goal of this study was to determine whether blood OC concentrations can reliably predict those in adipose tissue of sea turtles. Paired fat and blood samples were collected from 44 live, juvenile loggerhead sea turtles and 10 juvenile Kemp's ridley sea turtle carcasses. OCs were analyzed using gas chromatography with electron capturedetection and mass spectrometry. For both species, lipid-normalized OC concentrations measured in the blood significantly correlated to levels found in the fat samples. This result suggests that sea turtle blood is a suitable alternative to fatty tissues for measuring OCs, because blood concentrations reasonably represent those observed in the paired fat samples. However, blood OC concentrations calculated on a wet mass basis were significantly and inverselycorrelated to lipid content in the fat samples. Therefore, caution should be used when monitoring spatial or temporal trends, as OC levels may increase in the blood following mobilization of fat stores, such as during long migrations, breeding, or disease events.
Citation: Environmental Toxicology and Chemistry
Pub Type: Journals
blood fat, kemp's ridley, loggerhead, organochlorine pesticides, polychlorinated biphenyls, sea turtle