pected but are confirmed by data from 

 other sites near Panama City. The high 

 concentrations at one site in Choc- 

 tawhatchee Bay, FL, have not been 

 confirmed by results from other sites. 



If our objective had been to identify the 

 most contaminated sediments in the 

 Nation, even the highest concentrations 

 at NS&T sites could have been ex- 

 ceeded. For example, Rodgerson et al. 

 (1985) found levels of tPAH, tPCB, 

 cadmium, copper, lead, and zinc in Black 

 Rock Harbor in Bridgeport, CT, that are 

 higher than any found at NS&T sites. 

 Levels of tPAH, silver, mercury, and 

 lead in industrial waterways of Seattle 

 and Tacoma have been found in excess 

 of all NS&T concentrations (Malins et 

 al., 1982). 



As already stated, the NS&T site in the 

 Elizabeth River may not be a represen- 

 tative site, but a detailed sampling of 

 that river by Huggett et al. (1 987) yielded 

 levels of tPAH that exceed those re- 

 ported at any NS&T site. While sedi- 

 ments at all NS&T sites in Boston Har- 

 bor show high levels of tPAH, they are 

 not as high as some of those reported by 

 Shiaris and Jambard-Sweet (1 986) who 

 analyzed a similar suite of PAH com- 

 pounds in sediments from around piers 

 and other inner parts of Boston Harbor. 

 There are many NS&T sites in Southern 

 California, but with a single exception, 

 none have high levels of tPAH in sedi- 

 ments. Nevertheless, high concentra- 

 tions have been found near discharges 

 and centers of industrial activity (Ander- 

 son and Gossett, 1 987). Sampling on a 

 much finer spatial scale than the NS&T 

 Program could yield much higher levels 

 of contamination, but they would be of 

 little spatial significance from a national 

 perspective. However, this fact illus- 



trates the need for more detailed moni- 

 toring programs in selected areas for 

 local decision-making. 



Fifty-five sites yielded only sandy sedi- 

 ments and have not, therefore, contrib- 

 uted to defining the spatial distribution of 

 contamination. For the most part this is 

 not a severe problem because, on a 

 national scale, those sites are near other 

 sites that have fine-grained sediment. 

 On the California coast, however, only 

 sand was collected at most sites on the 

 offshore islands and along the rocky 

 shore north of Point Conception. There 

 are no samples to reveal whether any of 

 these sites are among the more con- 

 taminated. We can, with some reserva- 

 tion, use data from analyses of mussel 

 tissues to gauge contaminant levels at 

 these sites. The reservations are due to 

 the fact that mussels and oysters do not 

 accumulate chemicals with equal profi- 

 ciency (NOAA, 1 989) , and so we cannot 

 usually compare chemical concentra- 

 tions in oysters with those in mussels. 

 This same problem limits our ability to 

 compare results across the Nation from 

 different fish species sampled through 

 the Benthic Surveillance component of 

 the NS&T Program. 



NOAA has collected mussels at a total 

 of 96 sites. If the data for those 96 sites 

 are treated as we have treated the data 

 fromthe 232fine-grained sediment sites, 

 "high" concentrations can be defined in 

 the same way. Mussels at sandy sites 

 on the offshore islands and along the 

 northern coast of California often con- 

 tain high concentrations of tDDT. This is 

 consistent with data from the few sites in 

 that areathat did have fine-grained sedi- 

 ment and is related to the major histori- 

 cal discharges of DDT from production 

 facilities in Los Angeles. Except for 



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