CHANGES IN THE AMOUNT AND PROPORTIONS OF DDT AND ITS 

 METABOLITES, DDE AND DDD, IN THE MARINE ENVIRONMENT 



OFF SOUTHERN CALIFORNIA, 1949-72 



John S. MacGregori 



ABSTRACT 



This paper is about the contamination of the ocean and its biota off southern Cahfornia by the pesticide, 

 DDT. The accumulation of DDT and the changes in proportions of DDT and its metabolites in the ocean 

 are described for the years 1949 to 1972 especially as they are reflected in the myctophid fish, 

 Stenobrachius leucopsarus. This time period was characterized by continuous dumping of DDT wastes 

 into the ocean by a large manufacturer of DDT and the cessation of this dumping in 1970. Aspects and 

 implications of the pesticide pollution problem in the marine environment are discussed. 



In January and May 1970, the Fishery-Ocean- 

 ography Center, La Jolla, Calif., collected 

 samples of fish off southern California and Baja 

 California as their part in a survey of chlorin- 

 ated hydrocarbon (CHC) pesticides in marine 

 fishes by the U.S. fish and Wildlife Service 

 Bureau of Commercial Fisheries (now the Na- 

 tional Marine Fisheries Service). Each sample 

 consisted of the livers of several specimens of a 

 single species from one locality. The samples 

 were sent to the Environmental Protection Agen- 

 cy Laboratory at Gulf Breeze, Fla., for analysis. 

 The results (Duke and Wilson, 1971) showed 

 that off southern Baja California 9 samples (170 

 fish) contained an average of 0. 14 parts per million 

 (ppm) wet weight of DDT and its metabolites; in 

 Sebastian Vizcaino Bay (central Baja California) 

 3 samples (29 fish) averaged 1.2 ppm; along the 

 southern California coast south of Oceanside and 

 at two offshore banks 15 samples (179 fish) aver- 

 aged 13 ppm; in Santa Monica Bay 8 samples (65 

 fish) averaged 370 ppm. Two samples (26 fish) of 

 Pacific hake, Merluccius productus, taken by a 

 Russian trawler off northern California and 

 Oregon averaged 2.7 ppm, and fish sampled 

 farther to the north by the Seattle Laboratory 

 contained less than 1 ppm or no detectable DDT 

 residues in the livers. The highest levels of DDT 

 and its metabolites were found in the Los Angeles 

 area with DDT levels declining greatly in samples 



'Southwest Fisheries Center, National Marine Fisheries Ser- 

 vice, NOAA, P. O. Box 271, La Jolla, CA 92037. 



taken to the north, south, and offshore from Los 

 Angeles. 



Previous pesticide residue surveys of marine 

 birds and fish (Keith and Hunt, 1966; Risebrough 

 et al., 1967; Risebrough et al., 1968) had been 

 confined primarily to central California and did 

 not reveal the extent of DDT pollution in the ocean* 

 off Los Angeles. Risebrough et al. (1967) reported 

 one sample of northern anchovy, Engraulis mor- 

 dax, taken off Los Angeles that contained 12.7 

 ppm DDT and its metabolites compared with addi- 

 tional samples of anchovies and three other 

 species offish taken north of Los Angeles to San 

 Francisco that ranged in DDT residue content be- 

 tween 0.2 and 2.8 ppm. 



In the spring of 1969, Keith, Woods, and Hunt 

 (1970) investigated the breeding pelican, 

 Pelecanus occidentalis, colony on Anacapa Island, 

 about 35 nautical miles west of Santa Monica Bay, 

 and found extensive reproductive failure caused 

 by thin-shelled eggs which broke under the brood- 

 ing pelicans. They found that the contents of a 

 composite sample of many broken eggs contained 

 1,818 ppm DDT residues (lipid basis) while nine 

 intact eggs averaged 1,215 ppm. They also sam- 

 pled pelican eggs from three breeding colonies in 

 the Gulf of California and found DDT residues 

 averaging 58, 61, and 105 ppm. Jehl (1970) sam- 

 pled pelican eggs from Los Coronados Islands, 

 about 95 nautical miles south of Anacapa. These 

 contained 810 ppm DDT residues. At San Martin 

 Island 250 nautical miles south of Anacapa, egg 

 residues were 192 ppm. 



Manuscript accepted October 1973. 



FISHERY BULLETIN: VOL. 72, NO. 2, 1974. 



275 



