WATER - ACCOMMODATED 

 FRACTION 



JWUoju^JL 



-**k~ 



PROCEDURAL BLANK 



J 



Figure 2-2.— Gas chromatograms of the water-accommodated frac- 

 tion of gasoline and a procedural blank. Both analyses were run on a 

 30 m SE-52 glass capillary column: 35 t for 4 min, the 57mm to 

 250 °C. 



pounds (70%) than the lower molecular weight compounds (50%). 

 This relatively greater loss of low end components was found to oc- 

 cur during the final volume reduction phase of analyses. 



While visible slicks and gasoline odors were not apparent when 

 the water samples were taken, comparisons of gas chromatograms 

 from gasoline standards with those from water samples from sta- 

 tions 3, 4, and 7 clearly indicated the presence of gasoline com- 

 pounds (for station 7, see Figure 2-3). GC-MS analysis cor- 

 roborated the presence of gasoline by identifying alkylated 

 benzenes, indane, naphthalene, and alkylated naphthalenes in ex- 

 tracts from these water samples. The levels of gasoline in these 

 samples ranged from 3 to 12 ppb, with only trace amounts present 

 in the sample from station 2. These stations were southwest of 

 Watch Hill Reef which was the direction the slick moved before 

 dissipating (Fig. 2-1). Samples from station 1, to the south of 

 Watch Hill Reef, and from control station 1 1 , to the east, did not 

 show detectable levels of gasoline compounds. When compared 

 with the gasoline standards and the water-accommodated fraction, 

 chromatograms of water samples showed relative decreases in the 

 amounts of lower molecular weight gasoline compounds (Fig. 2-3). 

 While these decreases were at least partly due to losses in the final 

 volume reduction during analysis, they may also reflect greater 

 volatilization of the low molecular weight compounds to the at- 

 mosphere during environmental exposure. 



With the exception of the sea scallop adductor muscle, which 

 showed very low levels of compounds on gas chromatograms, 



samples of shellfish tissues showed low levels of compounds in the 

 molecular weight region of gasoline. Comparisons of gas 

 chromatograms of a water-accommodated gasoline standard with 

 those from shellfish suggested the presence of gasoline compounds 

 in these tissue samples (Fig. 2-4). The correlation of peak distribu- 

 tion patterns in gas chromatograms from the gasoline standards 

 and the bivalve tissues was not as clear as with the water samples 

 because of the low levels found in the tissues, and due to interfering 

 biogenic material. However, GC-MS analysis of tissues of the 

 Mercenaria mercenaria samples showed the presence of hydro- 

 carbon compounds typical of gasoline. Comparison with gas 

 chromatograms from other bivalve samples suggested that they also 

 may have contained these gasoline compounds. Since control 

 organisms sampled prior to the spill were not available, it was not 

 possible to determine if the presence of these compounds in the 

 organisms resulted from the spillage of gasoline from the Ocean 250 

 or from other sources such as industrial and municipal wastes. 



The accumulation and depuration of hydrocarbons from 

 petroleum fuels by filter-feeding bivalves has been investigated 

 (Blumer et al. 1970; Lee et al. 1972; Stegeman and Teal 1973; 

 DiSalvo et al. 1975; Boehm and Quinn 1977; among others). In 

 general these studies found that the majority of accumulated 

 petroleum hydrocarbons were rapidly depurated from the 

 organisms; however, Blumer et al. (1970) with Crassostrea virginica, 

 and Boehm and Quinn (1977) with Mercenaria mercenaria found 

 slow depuration of accumulated petroleum hydrocarbon com- 



