Acknowledgments 



David G. Smith, Marine Research, Inc., Woods 

 Hole, Mass., identified the specimens. Equipment 

 and facilities were furnished by the University of 

 Maine, Orono, Maine. P. C. Jensen operated the 

 RV Cypris. Research funds for this and associated 

 research were provided by the Maine Yankee 

 Atomic Pow'.jr Company. 



Literature Cited 



BiGELOW, H., AND W. SCHROEDER. 



1953. Fishes of the Gulf of Maine. U.S. Fish Wildl. Serv., 

 Fish. Bull. 53, 577 p. 

 Graham, J. J., and P. M. W. Venno. 



1968. Sampling larval herring from tidewaters with buoyed 

 and anchored nets. J. Fish. Res. Board Can. 25:1169-1179. 

 Recksiek, C, and J. D. McCleave. 



1973. Distribution of pelagic fishes in the Sheepscot 

 River— Back River estuary, Wiscasset, Maine. Trans. 

 Am. Fish. Soc. 102:541-551. 

 Schmidt, J. 



1931. Eels and conger eels of the North Atlantic. Nature 

 (Lond.) 128:602-604. 

 Stickney, a. p. 



1959. Ecology of the Sheepscot River estuary. U.S. Fish 

 Wildl. Serv., Spec. Sci. Rep. Fish. 309, 21 p. 



William J. Hauser 



University of California-Riverside 

 Imperial Valley Field Station 

 lOOJ, East Holton Road 

 El Centra, CA 922i3 



CHLORINATED HYDROCARBONS IN 



SEA-SURFACE FILMS AND SUBSURFACE 



WATERS AT NEARSHORE STATIONS AND IN 



THE NORTH CENTRAL PACIFIC GYRE 



Chlorinated hydrocarbons, DDT residues, and 

 polychlorinated biphenyls (PCB's) entering the 

 oceans via atmospheric transport, runoff, and 

 outfalls (National Academy of Sciences 1971) may 

 be concentrated in the lipid constituents (Garrett 

 1967; Duce et al. 1972) found in surface films. The 

 chlorinated hydrocarbons can then enter marine 

 food chains, most probably by association with 

 particulate detritus and subsequent ingestion by 

 filter- feeding organisms. Further concentration in 

 higher trophic levels is well documented (see, for 

 example, Harvey et al. 1971) and will not be dis- 

 cussed here. 



There have been only two reported studies on 

 the concentration of DDT residues and PCB's in 

 surface films. Seba and Corcoran (1969) found high 

 concentrations of p,p'DDT, p,p'DDE, o,pDDT, 

 aldrin, and dieldrin in the surface microlayer 

 collected at locations in Biscayne Bay, Fla., and 10 

 miles offshore in the Florida Strait. Duce et al. 

 (1972) found that PCB's (but no DDT residues) 

 were concentrated in surface films from 

 Narragansett Bay, R.I. Seawater collected at 1-2 

 m in the California Current was analyzed for DDT 

 residues (Cox 1971) and these results will be taken 

 as subsurface water concentrations in California 

 coastal waters. 



This note reports on the content of p,p'DDT, 

 p,p'DDE, and PCB's in surface films collected at 

 coastal stations off southern California and 

 Mexico; and in surface films, subsurface waters, 

 and particulate matter from the North Central 

 Pacific Gyre (Table 1). 



Methodology 



All surface films were collected with a Monel' or 

 stainless steel screen (Garrett 1965) into 2.5-liter 

 glass bottles. The coastal samples (SIO 1-2; M 1-4) 

 were poisoned with mercuric chloride. The Cato 

 samples were filtered on shipboard through sol- 

 vent-extracted and ignited GF/C glass-fiber 

 filters. The filters were frozen in glass vials at 

 -20°C, and the filtrate preserved with 75 ml of 

 hexane. Subsurface samples were collected in 2.5- 

 liter glass bottles 10-15 cm below the surface and 

 treated as above. In all operations the surface films 

 were collected from a skiff at least 0.5 mile upwind 

 from the ship. All glassware, screens, filters, etc., 

 were scrupulously freed of organic matter by ig- 

 nition at 550°C, rinsing with double distilled sol- 

 vents, or both. 



In the laboratory, the filtrates were acidified to 

 pH 2 with distilled 6N HCl and extracted with 

 three 60-ml portions of hexane. The hexane ex- 

 tracts were dried by passage through anhydrous 

 Na2S04, and then concentrated to 10-15 ml in a 

 Kuderna-Danish evaporator. This extract was 

 further reduced to 50 jul in vacuo, put onto an 

 alumina microcolumn (McClure 1972), and eluted 

 with 3.5 ml of hexane. The eluate was dried in 

 vacuo and taken up in 50 /aI of isooctane. The filters 

 were extracted in a soxhlet overnight with 20 ml of 



'Reference to trade names does not imply endorsement by the 

 National Marine Fisheries Service, NOAA. 



445 



