40,000,000 Bq of iodine-131 in a single bed of kelp off Southern California — Amount most likely larger

Source: Environmental Science & Technology
Author: Steven L. Manley and Christopher G. Lowe, Department of Biological Sciences, California State University
Publication Date (Web): March 6, 2012

[...] Macrocystis is the keystone species supporting the kelp forest ecosystem, which is highly productive with complex community structure. Using a canopy density of 3.5 kg fresh weight m−2, the amount of 131I present in California kelp ranged from 0.3 to 1.3 kBq m−2 of canopy.11 Our estimate of the area covered by the Corona del Mar Macrocystis canopy was 33 000 m2 yielding a total of 40 MBq 131I sequestered into this kelp bed canopy. The total amount of 131I taken up by the canopy was most likely larger than that measured in the canopy tissue because iodine taken up by canopy blades is translocated throughout the kelp body as iodide. [...]