CHAPTER 11: THE ANALYTICAL CHEMISTRY OF MYTILUS EPULIS , MACOMA BALTHICA 

 SEDIMENT TRAP AND SURFACE SEDIMENT SAMPLES- 

 (Paul D. Boehm, Judith Barak, David Fiest and Adria Elskus) 



11.1 Introduction 



It has become increasingly apparent in recent years that the tem- 

 poral impacts of spilled oil in the marine environment become more 

 prolonged when the fate of petroleum hydrocarbons includes transport 

 into the sediment. Recent studies by Teal et al. (1978), Keizer et al. 

 (1978), and Mayo et al. (1978) indicate that aromatic and aliphatic 

 hydrocarbons from spilled petroleum persist in the sedimentary environ- 

 ment for substantial periods of time (years). While degradative pro- 

 cesses, both chemical and microbial, act to alter the composition of the 

 oil in sediment, the toxicants and carcinogens may persist in the sed- 

 iment depending on factors such as sediment grain size, wave energy 

 (Owens, 1978), and oxidation state of the sediment (Anderson et al., 

 1978). 



There have been few field studies directly pertaining to the 

 sedimentation of oil owing to natural processes. At least three pro- 

 cesses can lead to the transport of petroleum from a positively buoyant 

 state in the water column to negatively buoyant state reaching the 

 sediment. First, some oils by virtue of an initial density close to 

 that of water (e.g., Bunker C) can weather at sea, lose volatile or 

 soluble components, and sink (Conomos, 1975). Such behavior was 

 apparently observed after a Bunker C spill in cold water off the coast 

 of Greenland (Mattson and Grose, 1978). Secondly, oil can adsorb to 

 living particulate matter or detrital particles and sink due to sedi- 

 mentation. This process is dependent on the availability of sediment 

 particles as well as the nature of the particulate matter (National 

 Academy of Sciences, 1975; Meyers and Quinn, 1973; Poirier and Thiel, 

 1941). Another route of transport to the benthos is by ingestion of oil 

 by zooplankters followed by fecal pellet transport (Conover, 1971). A 

 further indirect process is deposition after landfall by seaward trans- 

 port of beach and intertidal sediment with associated petroleum. 



" Work carried out by Energy Resources Co., Inc. under 

 Contract No. MO-A01-78-4178 to OCSEAP. 



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