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Analysis of dated oceanic sediments from the Santa Barbara Basin of the Southern California Bight has shown that deposition of polychlorinated biphenyls (PCB) began about 1945 and that DDE [1,1-dichloro-2-2-bis(p-chloro-phenyl)ethylene] first appeared in sediments deposited about 1952. Concentrations of both show a progressive increase through 1967; estimated deposition rates (in grams per square meter per year) in 1967 of DDE and PCB were 1.9 x 10(-4) and 1.2 x 10(-4), respectively.

In a study of the rate of production of four species of planktonic Foraminifera in the region of the California Current it was found that their life spans are of the order of 1 month. Reproduction seems to take place mainly in the upper hundred meters. Results are in contrast to previous evidence presented in favor of yearly life cycles and maturing at great depth in other species of planktonic Foraminifera.