TABLE 1: Attributes of Bivalves as Sentinel Organisms 



• A correlation exists between the pollutant content of the organism and the average 

 pollutant concentration in the surrounding habitat; contaminant concentration factors of 

 many-fold (over seawater concentrations) are common . 



• Bivalves are cosmopolitan, minimizing the inherent problems which arise when 

 comparing data from markedly different species; this issue will be more importent in 

 tropical areas. 



• Bivalves have reasonably high tolerance to many types of pollution and can exsist in 

 habitats contaminated within much of the known range of pollution. 



• Bivalves are sedentary generally and better representative of the study area than 

 mobile species. 



• Bivalves often are abundant in relatively stable populations that can be sampled 

 repeatedly throughout the study region. 



• Many bivalve species are sufficiently long-lived to allow the sampling of more than 

 one year-class, if desired. 



• Bivalves are often of a reasonable size, providing adequate tissue for analysis. 



• Bivalves are easy to sample and hardy enough to survive in the laboratory, allowing 

 defecation before analysis (if desired) and laboratory studies of pollutant uptake. 



• Several bivalve species tolerate a range of salinity and other environmental 

 conditions, making them hardy enough to be transplanted to other areas for 

 experimentation. 



• Bivalves are generally metabolically passive to the contaminants in question and not 

 alter the chemical after uptake; uptake by the organism provides an assessment of 

 bioavailability from environmental compartments. 



• Bivalves are commercially valuable seafood and a measure of chemical contamination 

 is of public health interest. 



