FISHERY BULLETIN: VOL. 78, NO. 1 



AROCLOR 1254 (1100 pg) 



TDE (40 pg) 



DDT (40 pg) 



Figure l. — Gas chromatographic curves of Aroclor 1254, the 

 PCB fraction of an extract from Spanish mackerel, and DDT and 

 its metabolites DDE and TDE; pg = picograms or 10 



54 



10 sets of red grouper was 0.008 ppm; for most 

 samples, PCB were not detectable. Black grouper 

 and gag contained slightly higher levels of iDDT 

 and PCB. Red snapper also contained little iDDT 

 (mean 0.039 ppm), but the PCB level in six sam- 

 ples exceeded 0.1 ppm. Only the two species of 

 mackerel consistently contained quantifiable 

 amounts of both SDDT and PCB. The mean levels 

 of SDDT were 0.144 ppm in Spanish mackerel and 

 0.177 ppm in king mackerel. The mean PCB level 

 in both species of mackerel was 0.32 ppm. The 

 highest levels of both chlorinated hydrocarbons 

 were found in one composite sample of king mack- 

 erel from the Florida Keys, 0.996 ppm iDDT and 

 1.8 ppm PCB. The data are summarized in Table 2. 

 The limited data in the literature convey a simi- 

 lar picture. Groupers of the genera Epinephelus 

 and Mycteroperca from the Gulf of Mexico and the 

 Grand Bahamas contained 0-0.10 ppm SDDT and 

 0.003-0.22 ppm PCB in muscle (Giam et al. 1974). 

 Red snapper from Mobile Bay, Ala., contained 

 0.086 ppm SDDT and 0.14 ppm PCB in the whole 

 animal; gray snapper, Lutjanus griseus, from 

 Jacksonville, Fla., 0.007 ppm SDDT and no PCB 

 in the whole animal (Markin et al. 1974). Small 

 Spanish mackerel (306 g) from the Savannah 

 River estuary in Georgia contained neither SDDT 

 nor PCB in muscle. (Butler^) Although somewhat 

 larger than those fish, the smallest fish in the 

 current study (475 g) contained barely detectable 

 amounts of these substances (0.008 ppm SDDT 

 and 0.034 ppm PCB). Markin et al. (1974) found 

 0.04-0.16 ppm SDDT and <0.01-0.18 ppm PCB in 

 seven whole Spanish mackerel from the south- 

 eastern United States. A single sample of king 

 mackerel muscle from the Gulf of Mexico off 

 Mexico contained 0.024 ppm SDDT and 0.034 ppm 

 PCB (Giam et al. 1972). Atlantic mackerel, 

 Scomber scombrus, collected in 1971-72 in Cana- 

 dian waters (Sims et al. 1977) contained more 

 SDDT (0.26 ppm) and PCB (0.41 ppm) in the "edi- 

 ble portion" (which may have contained skin 

 and/or bones) than did skinless fillets of either 

 species of mackerel examined in my study. On the 

 other hand, muscle from Atlantic mackerel from 

 the Bay of Fundy-Gulf of Maine contained the 

 same level of PCB (0.35 ppm) (Zitko et al. 1972). 

 The proportions of p,p '-DDT and its metabolites 

 were very similar in the king and Spanish mack- 

 erel examined in our study. p,p'-DDE is the 



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g- 



"Butler, P. A. 1978. EPA-NOAA Cooperative Estuarine 

 Monitoring Program, Final Report, Gulf Breeze, Fla., 108 p. 



