The International Mussel Watch 



Generally, the quantitative composition of any sample matrix in a particular geographic 

 region does not vary dramatically even over relatively long periods unless the region is subject to 

 an acute input of a particular contaminant. Once the composition of each peak has been determined 

 unambiguously with the techniques indicated above, identification in routine analyses of a series of 

 such samples can usually be made on the basis of retention time data performed with only the one 

 column type. 



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