the effects on plankton and benthic animals such as small bivalves and polychaete 

 worms. The MERL microcosms are fiberglass tanks 5.5 X 1.8 m ( 18 X 6 ft) in diam- 

 eter with 40 cm ( 1 6 in) of sediment in the bottom. They have been shown to simulate 

 Narragansett Bay to an extent that pollution experiments are realistic when a control 

 tank is used (Pilson et al.. 1 979). Numerous experiments have been done in this 

 system using No. 2 fuel oil as the pollutant. It was found that added oil was 40 to 60 

 percent removed by evaporation, but significant quantities of both saturated and 

 aromatic hydrocarbons were transported to the bottom by adsorption on sinking 

 particles (Gearing et al., 1979). At water column concentrations of 93 ppb total 

 hydrocarbon, most species of benthic animals declined relative to a control tank. 

 These effects were obvious for a year (Grassle et al., 1980). Microcosm experiments 

 are difficult because they involve large facilities and team research, but they are very 

 promising as a tool for evaluating the potential effects of petroleum and other toxic 

 substances on the marine environment. 



Planned and unplanned spills of oil in salt marshes have been studied (Lytle, 

 1975). These opportunistic studies have not provided in-depth multidisciplinary 

 data. They have shown that more toxic oils such as No. 2 fuel oil can have long-term 

 impacts on marsh plants. Small spills of crude oil have an impact related to the 

 amount of oil spilled and the care exercised in the cleanup operations. The study of 

 the Miguasha Marsh. Quebec, following a spill of Bunker C fuel oil, showed that oil 

 could persist in sediment and be redistributed by tidal waters. Nevertheless, from a 

 revegetation point of view, manual cleanup without burning was recommended by 

 Vandermeulen and Ross (1977). 



PETROLEUM IN THE ENVIRONMENT 



During the seventies, our knowledge of the kind and concentration of petroleum in 

 the environment has increased enormously. There are several reasons for this. The 

 driving force is the increased transport and use of petroleum coupled with a propor- 

 tionate concern for the impact of oil on the environment. During this time enabling 

 developments included the rapid development of analytical instrumentation such as 

 gas and liquid chromatography, gas chromatography coupled to mass spectrometry 

 (GC MS), and compact, dedicated computer-assisted data acquisition and analysis 

 systems. All of these developments were possible because private, state, and federal 

 agencies made substantial funds available. It may be argued that the limiting factor 

 for environmental chemistry is the number of well-trained scientists with ideas. 



Programs that have undertaken to measure the baseline level of petroleum hydro- 

 carbons in the marine environment clearly reflect this growing analytical sophistica- 

 tion in the data and in the cost of obtaining the data. In 1971-1972 the U.S. Inter- 

 national Decade of Ocean Exploration (1DOE) carried out baseline studies of pollu- 

 tants including petroleum in the U.S. coastal waters. These investigations by a group 

 of university scientists, despite being only one year in duration, stimulated a follow- 

 up conference to recommend "that a continuing research program to determine 

 inputs, dispersal paths and present levels of . . . petroleum hydrocarbons in repre- 

 sentative plants and animals of coastal and open ocean zones be immediately initi- 

 ated with the objectives of evaluating hazards to living processes and of defining 

 sources of these materials (International Decade of Ocean Exploration, 1972). Such 

 a continuing research program has in fact been operative during the decade although 

 it is a patchwork of various organized programs and efforts by individual scientists. 



Beginning in 1974, the U.S. Bureau of Land Management (BIM), initiated a com- 

 prehensive study of offshore regions, mostly outer continental shelf areas, of the 

 United States that were being considered for petroleum exploration. Measurements 

 of petroleum hydrocarbon baselines for water, biota, and sediment were major goals 

 for this program. This program involved many of the marine organic geochemists in 

 the United States. At this time no single document summarizes the overall results of 

 this program although such a document might be useful. The results where published 

 and appropriate are cited herein without identification of the funding source. 



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