Relative distribution of polychlorinated biphenyls among tissues of neonatal American alligators (Alligator mississippiensis)

Recent papers have investigated the utility of chemical analysis of the cho rioallantoic membrane (CAM) as a nonlethal indicator of avian and reptilian exposure to persistent environmental contaminants. This study was undertak en to evaluate the chemical distribution among fat, CAM, and residual yolk tissues of live neonatal American alligators (Alligator mississippiensis) t o investigate the potential utility of CAM use as a nonlethal indicator of exposure to polychlorinated biphenyls (PCBs). CAMs were collected from neon atal alligators at hatch, whereas yolk sacs and fat tissues were taken from each animal at euthanization (3 weeks posthatch). All collected tissue sam ples were separately Soxhlet extracted and analyzed by GC/ECD for PCBs. Log normalized, individual PCB congener concentrations in CAMs were significan tly correlated with concentrations in fat (r(2) = 0.62) and yell; (r(2) = 0 .56) tissues. Coefficients of determination from comparisons of homologue g roup concentrations varied from 0.13 to 0.90. Residue levels in neonatal ov iparous organism tissues may be qualitatively assessed through chemical ana lyses of CAM tissues removed from discarded eggshells.