408 



Hniihiii Influences — Our Livini> Resinirces 



Contaminants 

 in Coastal 

 Fish and 

 Mollusks 



by 



Donna Turgeon 



Andrew Robertson 



National Oceanic and 



Atmospheric Administration 



Table. Chemicals measured in tiie 

 National Oceanic and Atmospheric 

 Administration's National Status 

 and Trends Program. 



Historically. U.S. coastal fish and shellfish 

 have been plentiful, supporting native car- 

 nivores such as ospreys. bald eagles, striped 

 bass, sharks, sea lions, poipoises. and whales in 

 ecosystem food webs. Since the I960"s. howev- 

 er, the capacity of coastal ecosystems to pro- 

 duce abundant fish and shellfish has declined. 

 Increasingly frequent reports of closures of 

 shellfish beds and bathing beaches, contamina- 

 tion of living resources and habitats by toxic 

 chemicals, decreases in commercial fish stocks, 

 shallow-water strandings of porpoises and pilot 

 whales, losses of wetland habitat, and spread of 

 toxic and nuisance algal blooins indicate there 

 has been widespread environmental degrada- 

 tion. 



As part of the national response to concerns 

 over the deteriorating health of our coastal 

 ecosystems, several federal and state programs 

 monitor changes in the levels of toxic chemicals 

 in select organisms at coastal sites. In general, 

 contaminant levels have been found to be hold- 

 ing steady or. in the case of several contami- 

 nants, decreasing in coastal areas over the past 

 few years, reversing the trends of contaminant 

 increases that occurred in the first two-thirds of 

 this century. 



The National Oceanic and Atmospheric 

 Administration (NOAA) initiated its National 

 Status and Trends (NS&T) Program in 1984 



with its National Benlhic Surveillance Project. 

 The project monitors concentrations of about 70 

 chemical contaminants (Table) in fish livers and 

 sediments and investigates some of the effects 

 of these chemicals on fish (e.g., liver tumors, 

 reproductive impairment, fin loss) from 

 nearshore waters of the Atlantic, Gulf of 

 Mexico, and Pacific coasts, including Alaska. In 

 1986, the NS&T Program began its Mussel 

 Watch Project to monitor concentrations of the 

 same contaminants in the tissues of bivalve 

 mollusks (primarily mussels and oysters) and 

 sediments. More than 350 coastal sites (Fig. 1) 

 of the continental United States, off Hawaii. 

 several Caribbean islands, and in the Great 

 Lakes are regularly monitored. Since 1986 the 

 NS&T Program also has conducted intensive 

 studies of the magnitude and extent of contami- 

 nant effects on selected indicator species from 

 the most contaminated U.S. estuaries (Wolfe et 

 al. 1993). 



Methods 



All sites are located away from known point 

 sources and dumpsites (Lauenstein et al, 1993). 

 Sites are sampled every 1 -2 years for biota and 

 less frequently for sediments. Sediments for 

 chemical analyses are collected from the top 2 

 cm (0.75 in) of grab sainples. Mollusks (e.g., 

 oysters, clams, and mussels) are dredged from 

 deep subtidal zones or hand-collected in inter- 

 tidal to shallow subtidal zones. Fish are sampled 

 by otter trawl tows in depths of 1-70 m (3-230 

 ft). Details of sampling protocols and methods 

 of analysis are described elsewhere (Lauenstein 

 andCantillo 1993). 



Sediment contaminant concentrations have 

 been adjusted for particle size to account for 

 differences in concentrations due to variations 

 in physical properties of absoiption surfaces 

 among large-grained sands, fine muds, and sed- 

 iment mixtures (NOAA 1988). Measureinents 

 for individual chemicals have been combined 

 for groups of related compounds. Thus total 

 PCB (polychlorinated biphenyl) is based on the 

 sum of the concentrations of 20 PCBs: total 

 PAH (polycyclic aromatic hydrocarbon) is the 

 sum of 24 PAH coinpounds; total DDT (1,1"- 

 [2.2.2-trichloroethyiidene]bis[4-chloroben- 

 zene]) is the sum of the concentrations of DDT 

 and its metabolites; and total chlordane is the 

 sum of the concentrations of two major con- 

 stituents of chlordane mixtures (c«-chIordane 

 and mv/(.s-nonachlor) and two minor compo- 

 nents (heptachlor and heptachlorepoxide). 



The primary species of mollusks monitored 

 are the eastern oyster {Crossostrea virginica), 

 the northeastern and west coast species of mus- 

 sels (Mytilus ediilis. M. tmssiilits, and M. 



