Particle-Induced X-ray Emission Analysis of Elements in Plasma from Wild and Captive Sea Turtles (Eretmochelys imbricata, Chelonia mydas, and Caretta caretta) in Okinawa, Japan Kazuyuki Suzuki & Jun Noda & Makio Yanagisawa & Isao Kawazu & Kouichiro Sera & Daisuke Fukui & Mitsuhiko Asakawa & Hiroshi Yokota Received: 13 December 2011 / Accepted: 22 February 2012 / Published online: 9 March 2012 # Springer Science+Business Media, LLC 2012 Abstract The aim of this study was to evaluate the reliabil- ity of direct determination of trace and major element con- centrations in plasma samples from wild (six hawksbill, nine green, and nine loggerhead) and captive sea turtles (25 howksbill, five green, and three loggerhead) in Okinawa, Japan. The particle induced X-ray emission method allowed detection of 23 trace and major elements (Al, As, Br, Ca, Cl, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Ni, P, Pb, S, Se, Si, Sr, Ti, Y, and Zn). The wild sea turtles were found to have high concentrations of As and Pb in plasma compared with captive, but there were no significant changes in the Al and Hg concentrations. Loggerhead sea turtles were found to have significantly higher accumulation of As and Pb in plasma in comparison to other species. These findings may be useful when adjusting environmental and species-related factors in severely polluted marine ecosystems. Our results indicate that measuring the plasma As and Pb concentra- tions in wild sea turtles might be of help to assess the level of pollution in marine ecosystems, keeping in mind that loggerhead sea turtles had been shown to have higher levels of As and Pb in plasma. Keywords Habits . PIXE . Sea turtle . Trace element . Pollution Abbreviations CCL Curved carapace length CCW Curved carapace width OERC Ocean Expo Research Center PCV Packed cell volume PIXE Particle induced X-ray emission Introduction In comparison to terrestrial animals, marine animals are known to accumulate higher levels of elements [1]. Because many chemical pollutants persist in tissues and can bio- accumulate over time, they could reach toxic levels in sea turtles, which have a long life span of over 50 years [2] and occupy higher trophic levels in the marine food chain [3]. In this regard, sea turtles are considered of increasing interest as potential biomonitors for pollution in marine ecosystems [4]. Several species of sea turtles live in Japanese coastal waters [2]. Currently, three of seven marine species, the K. Suzuki : J. Noda : D. Fukui : M. Asakawa : H. Yokota School of Veterinary Medicine, Rakuno Gakuen University, 582 Midorimati, Bunnkyoudai, Ebetsu, Hokkaido 069-8501, Japan M. Yanagisawa : I. Kawazu Ocean Expo Research Center, 888 Ishikawa, Motobu-cho, Kunigami-gun, Okinawa 905-0206, Japan K. Sera Cyclotron Research Center, Iwate Medical University, Tomegamori, Takizawa, Iwate 020-0173, Japan K. Suzuki (*) Department of Large Animal Clinical Sciences, School of Veterinary Medicine, Rakuno Gakuen University, 582 Midorimati, Bunnkyoudai, Ebetsu, Hokkaido 069-8501, Japan e-mail: kazuyuki@rakuno.ac.jp Biol Trace Elem Res (2012) 148:302–308 DOI 10.1007/s12011-012-9375-z