PNNL: Uranium Signatures in 20th Century Turtles, Tortoises, and Sea Turtles from Nuclear Sites
A presentation by Cyler Conrad
Tuesday, October 10
Via Zoom at 5pm
Long-lived organisms, especially those that grow sequential tissues, provide a unique ability to examine diachronic records of environmental information over time – think of tree rings, or layers in a mollusk shell. This is particularly true for chelonians (turtles, tortoises, and sea turtles) who grow their shell scute keratin in layers throughout the course of their life. In this presentation, I discuss the results of our ongoing research funded by Los Alamos National Laboratory’s, Laboratory Directed Research and Development program investigating the bioaccumulation, retention, and signatures of anthropogenic radionuclides (especially uranium) in a variety of chelonians from nuclear sites. By analyzing turtles, tortoises, and sea turtles from former nuclear testing sites – the Republic of the Marshall Islands and the Nevada Test Site – and nuclear processing sites – the Savannah River Site and the Oak Ridge Reservation – we identify legacy uranium signatures in scute growth rings that are associated with 20th century nuclear activities at each location. These results highlight the ability of using chelonian scutes as a passive, and proxy, record of anthropogenic radionuclide contamination in both past and present contexts.