Heavy metal monitoring in sea turtles using eggs

Abstract

Heavy metals in the muscles, livers, kidneys and eggs of loggerhead turtles and green sea turtles were analysed to develop a non-killing method of heavy metal monitoring using eggs. Heavy metal concentrations were higher in the liver and kidney than in the muscle and eggs of loggerhead turtles. Within an egg, yolk contained the highest concentrations and burdens of heavy metals. Heavy metal concentrations in egg yolks within the oviducts of a single loggerhead turtle were uniform without significant intra-oviduct variation. Similarly, there were no inter-clutch differences of an individual green turtle during one nesting season. Heavy metal concentrations in the yolk of eggs from the oviduct indicate the accumulation levels in female turtles, suggesting that the analysis in yolks of sea turtle eggs collected randomly from any clutch enable the estimation of the heavy metal concentrations in nesting female turtles, since there is less fluctuation of heavy metal concentrations in yolks of eggs laid by nesting loggerhead and green turtles.