Organochlorine contaminants in sea turtles: correlations between whole blood and fat.
Monitoring toxic organochlorine (OC) compounds is an important aspect in wildlife studies, especially in protected species such as sea turtles. The goal of this study was to determine whether blood OC concentrations can predict those in adipose tissue of sea turtles. Blood offers many benefits for monitoring OCs. It can be collected nondestructively from live turtles and can be sampled repeatedly for continuous monitoring. Organochlorine concentrations in blood may better represent the exposure levels of target tissues, but blood concentrations may fluctuate more than those in fatty tissues following recent dietary exposure or lipid mobilization. Paired fat and blood samples were collected from 44 live, juvenile loggerhead sea turtles and 10 juvenile Kemp's ridley sea turtle carcasses. Organochlorines were analyzed using gas chromatography with electron capture detection and mass spectrometry. Lipid-normalized OC concentrations measured in the blood significantly correlated to levels found in the fat samples of both species. 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 inversely correlated 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.
Duke University, Integrated Toxicology Program and Nicholas School of the Environment and Earth Sciences, Division of Coastal Systems Science and Policy, Beaufort, North Carolina 28516, USA. jennifer.keller@noaa.gov
Jennifer M
JM
Keller
John R
JR
Kucklick
Craig A
CA
Harms
Patricia D
PD
McClellan-Green
D000273:Adipose Tissue / Q000737:chemistry*; D000818:Animals; D001267:Atlantic Ocean; D002849:Chromatography, Gas; D004784:Environmental Monitoring / Q000379:methods / Q000706:statistics & numerical data*; D007306:Insecticides / Q000032:analysis* / Q000097:blood; D013058:Mass Spectrometry; D009657:North Carolina; D011078:Polychlorinated Biphenyls / Q000032:analysis* / Q000097:blood; D014426:Turtles / Q000378:metabolism*
D007306:Insecticides; D011078:Polychlorinated Biphenyls