the concentration expected from Fig. l. through the data points. From this Thus, there is little question that curve, the concentration of plutonium the plutonium levels in the air of expected in air at the latitude of Bikini Island around the first part Bikini during May 1972 is approxi- of June 1970 were above fallout- mately 16 aCi/m>. plutonium background levels for that normal median (21 aCi/m>) of actual latitude. concentrations at Bikini is only The only mechanisms that While the log could cause such levels are resus- slightly more than this value, the pension processes on the island. mean plutonium air concentration The median concentration at Bikini detected at Bikini during this period was very nearly equivalent to the (34 aCi/m>) was twice this expected . mean air concentration at New York value. during this period in 1970. were detected in the air at New York. Remember In this same month, 37 aci/m> that during 1970 the urine concentra- Again we find a similarity between tions from Bikini and New York were the levels of plutonium in Bikini and also comparable. New York air, and the Bikini mean Except for water and possibly some fish, no indigenous concentration is again higher than material was consumed at Bikini expected for this latitude from during 1968 and 1969. worldwide fallout concentrations, From this comparison of New York and Bikini, The 1972 data on air concentration the 1970 data strongly suggest a of plutonium at Bikini also showed a close correlation between plutonium strong geographic correlation. levels in air and concentrations in plutonium air concentrations in the urine. samplers increased from northwest to In May, 1972, air samplers were The southeast along the length of the again operated on Bikini Island at island. four different locations. the island have higher plutonium air 239,240 The . . Pu air concentration during this period ranged from less than 6 to 80 aCi/m>.’ The log normal median Therefore, some regions of concentrations than others. The . individual's inhalation exposure, then, must also depend on the time concentration over the island was spent in specific regions of the 21 aCi/mn, and the mean concentration island. was 34 aCi/m> In Fig. 2 the HASL In summary, the data on air con- air concentrations of plutonium centrations of plutonium at Bikini during May 1972 are plotted as a are rather sketchy, and we do not function of latitude.® A smooth know how different the concentrations continuous curve has again been drawn in large volumes of open air are from 9010225