1 Cesium radioisotope content of wild edible fungi, mineral soil, and surface litter in western 2 North America after the Fukushima nuclear accident. 3 4 Matthew J. Trappea, Leah D. Mincb, Kimberly S. Kittredgec, Jeremias W. Pinkd 5 6 a Department of Forest Ecosystems and Society, 321 Richardson Hall, Oregon State University, 7 Corvallis, Oregon, USA, 97331,
[email protected], corresponding author, Tel. 01- 8 541-737-6072 9 10 b Radiation Center, 100 Radiation Center, Oregon State University, Corvallis, Oregon, USA, 11 97331,
[email protected] 12 13 c Northwest Mycological Consultants, 702 NW 4th Street, Corvallis, Oregon, USA, 97330, 14
[email protected] 15 16 d Department of Anthropology, 238 Waldo Hall, Oregon State University, Corvallis, Oregon, 17 USA, 97331,
[email protected] 1 18 ABSTRACT 19 We measured activity levels of cesium radioisotopes 134Cs and 137Cs in wild edible fungi, 20 mineral soil, and surface litter of the west coast of North America from southern California to 21 northern Vancouver Island after the Fukushima nuclear accident. All activity measurements 22 were below governmental limits for human health. 137Cs activity increased to the north in 23 mineral soils and fungal samples, while 134Cs activity increased to the south in surface litter 24 samples. Chanterelles did not significantly bioconcentrate either radioisotope, but chanterelle 25 activity levels were correlated with those of mineral soil. Activity levels demonstrated a high 26 degree of variability, even in samples from the same site. In most cases the level of 137Cs 27 activity was substantially higher than that of 134Cs, suggesting that 137Cs was present in the 28 environment prior to the Fukushima release.