The slider turtle as an environmental sentinel: multiple tissue assays using flow cytometric analysis.

We used flow cytometry (FCM) to conduct a multiple-tissue assay on slider turtles (Trachemys scripta) inhabiting radioactive seepage basins. Duplicate samples of blood, heart, spleen and kidney were analysed on two different cytometers (Leitz MPV and Coulter Profile II), each employing distinct staining protocols (DAPI and PI, respectively). Both DAPI and PI assays of spleen cells demonstrated significantly greater variation in DNA content for the basin turtles than for 'control' animals from nearby, uncontaminated sites. Basin turtles also exhibited significant cell-cycle effects for blood and spleen, again revealed by both assays. These corroborative findings demonstrate the consistency and repeatability of FCM assays in environmental monitoring and identify the particularly sensitive nature of turtle blood and spleen to mutagenic agents. Our survey complements previous FCM studies on sliders from contaminated sites and thereby underscores the species' potential as a sentinel for biomarker assays.