The CPI ranges from values of 1, where oil is present, to values 

 greater than 1 if odd chain biogenic terrigenous n-alkanes dominate the 

 higher boiling n-alkanes. 



Quantification of aromatic hydrocarbons was accomplished using the 

 technique of mass fragmentography wherein the computer stored raw GC/MS 

 data is searched for parent ions (m+) and the total ion currents for 

 these ions is integrated and tabulated. Retention times of the parent 

 ion mass fragmentograms obtained were compared with authentic standards. 

 The total ion current for each parent ion is compared with that for the 

 internal standard (deuterated anthracene) and instrumental response 

 factors applied. Where authentic polynuclear aromatic hydrocarbon 

 (PAH) standards were not available for relative response factor 

 determination, a response factor was assigned by extrapolation. 



All of the above techniques were applied successfully to the 

 analyses of replicates of a NOAA intercalibration sediment sample, 

 Duwamish I, prior to commencement of the program and to Duwamish II 

 during the program. Additionally, the EPA "megamussel" intercalibra- 

 tion sample was successfully analyzed for PAH levels. 



2.2 Plant and Animal Tissues 



All specimens of wet tissue, freeze dried tissue, and plant 

 material were thawed and homogenized, or in the case of the seaweed 

 tissue were cut into small pieces, prior to placement in a digestion 

 flask. The samples were added to 250 ml Teflon screw top jars. The 

 digestion, extraction, and fractionation schemes were similar to those 

 developed by Warner (1976) except that the digestion was performed 

 using a 0.5 N KOH/distilled water/distilled methanol system heated in a 

 boiling water bath for 4 hours to achieve complete digestion and hence 

 release of hydrocarbons from the cellular matrix (Boehm et al . , 1982). 

 Internal standards were added prior to digestion and carried through 

 the entire procedure (Fig. 2.2) (f^ = androstane; f2 = deuterated 

 anthracene or phenanthrene) . 



The digestate was extracted three times with distilled hexane in 

 the jar, the mixture being centrifuged between extractions. The 

 extracts were combined, concentrated to 0.5 ml, weighed on a Cahn 

 electrobalance, and fractionated on an alumina over silica gel column 

 (see previous section) . Two fractions corresponding to the saturated 

 or fi (hexane eluate) and the aromatic/olef inic or f2 (hexane:methyl- 

 ene chloride eluate) hydrocarbons were obtained for gas chromatographic 

 and combined gas chromatographic/mass spectrometr ic analyses (GC/MS). 



41 



