28 with a higher activity density than perhaps the plant did, wr We ¢y also have the time lag which is involved hero in terns of what you might call specific activity -- tho activity of the P-52 as compared to the amount of stadl2 vhosphorous per se that is there, Obviously, this so2cific activity nas to decrease as is) you go down throuzh any food chain teecause you have tha tine DR, KETCHULi: a esay. & element with resosct ta radiozctive I knoyv that in the marine situation on &@ straight chemical basis, phosrvhorous is close to ten to the seventa, DR. FOSTER: the water, You ere talking cpout the plant versus We have an aquarium typo of exporinant where we know the quantities there a little nicer tran wa do in the window. We have concentration factors on the order of ten to the sixth from the water into the Planktonic algae in very low phesphorous concentrations in terms of the water. DR. KETCiIUGi: But you do not have any plant observations on the river? DR. FOSTER! Yes, we ean write dowm a concentration factor here in terms of the phesphorous in the river versu the plant, and it is on the order of 559,009 times. The samt, in terms of phosphorous -- it is on the order of-150,000 timss this in terns of radicactivity is not necessarily preciso in terms o Ks Of course, we do have differences -- (indicating) the phosphorous per se because of decay factors which are involves