MacGREGOR: AMOUNT AND PROPORTIONS OF DDT 



Table 5. — Distribution ofp.p'DDE.p.p'DDD andp.p'DDT in various animals from southern California marine waters. Porpoises 

 found dead on beach north of San Diego, various dates May 1970. Fishes and crustaceans taken in net haul in San Pedro Channel 

 4 August 1971. 



52% (26-81), DDD 20%, and DDT 28% of total 

 DDT. 



Keith and Hunt (1966) list DDT content for 

 samples of mammals, birds, and freshwater fishes 

 taken throughout California. The proportion of 

 DDE tends to be high in categories that include 

 birds of prey and fish eating birds, but varies con- 

 siderably in their other samples. In their warm- 

 water fish samples and the fish eating birds, white 

 pelican, western grebe, and common egret, DDD is 

 unusually high. This may be because of the former 

 use of DDD as a spray on some California lakes 

 (Murphy and Chandler, 1948; Brydon, 1955; Hunt 

 and Bischoff, 1960). 



Following the cessation of DDT dumping into 

 the ocean off Los Angeles in 1970, a change oc- 

 curred in the DDD:DDT ratios found in fish sam- 

 ples. The five S. leucopsarus taken in April 1972 

 contained 79% DDE, 12% DDD, and 9% DDT. Each 

 of the five specimens contained more DDD than 

 DDT. In the period 1949-70, only 8 out of more 

 than 500 S. leucopsarus tested contained more 

 DDD than DDT. The five myctophids taken in 

 April 1972 ranged from 40 to 50 mm SL, indicat- 

 ing that most or all of their growth had taken place 

 since dumping stopped in 1970. 



The shift in DDD:DDT ratios also appeared in 

 some other species. The ratios in rockfishes and 

 sablefish, Anoplopoma fimbria, taken in Santa 



Monica Bay in May 1970, indicated that DDT was 

 more abundant than DDD while 15 and 20 mo 

 later the reverse was true (Table 4, Figure 11). 

 The pelagic crustaceans and fish taken in the 

 midwater trawl in August 1971 (Table 5) did not 

 show the increased DDD to DDT ratio as did the 

 bottom fish taken at that time, or the five S. 

 leucopsarus taken in April 1972. A mud sample 

 taken in August 1971 (Table 4, Figure 12) about 3 

 nautical miles from the White Point sewer outfall 

 contained about twice as much DDD as DDT. 



The work of Burnett (1971) on DDT residues in 

 the sand crab along coastal California showed that 

 the high ratios of DDD to DDT were a local condi- 

 tion. Twelve samples taken in November 1970 and 

 February 197 1 from eight stations on either side of 

 the White Point sewer outfall between 33°22'N 

 and 34°28'N contained more DDD than DDT in all 

 but two samples. The 11 stations north and south 

 of this area all contained less DDD than DDT. The 

 four samples taken closest to the outfall averaged 

 more than three times as much DDD as DDT. 



This shift in DDD:DDT ratios was undoubtedly 

 caused by the deposits in the sewer system. 

 CSDLAC cleaning operations started in De- 

 cember 1970, and ended in July 1971. Although 

 large quantities of these deposits were removed 

 directly from the sewers, additional large quan- 

 tities were moved through the system to the White 



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