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94 PART A Chemical Methods ~ NTRODUCTION There have been many signif icant advances in the application of chemical analyses to all aspects of petroleum pollution in the marine environment since the last National Research Council (1975) publication. However, no one method of analysis can measure all components of petroleum or answer all requirements for research and monitoring. Many techniques have been applied to oil spill studies, monitoring of long term sources of input such as Sewage effluents and production platforms, and experi- mental studies of the fate and effects of petroleum in the marine environment. Concurrently, new equipment has been developed for the variety of sampling problems that have been encountered, and instru- mental techniques for real-time monitoring of petroleum components in water near oil spills have been successfully tested. The analytical methods applied to oil spill studies usually combine low resolution but relatively easily applied techniques, such as ultraviolet (W) fluorescence spectrometry, with high resolution but more costly and time-consuming techniques, such as glass capillary/gas chromatography/mass spectrometry (GC2/MS) computer systems. This also applies to monitoring of chronic inputs and analytical chemistry in support of exper imental studies of fate and effects. Two important issues that have sometimes been overlooked are (a) choosing the method (s) that will satisfactorily solve the analytical problem at hand; for example, gross levels of hydrocarbons in tissues as determined by nonspecific measurements such as ultraviolet fluor- escence have minimal use when the problem is to distinguish between chronic background hydrocarbon pollution of combustion origin, chronic petroleum pollution, biogenic hydrocarbon inputs, and additions of petroleum hydrocarbons from a recent oil spill; and (b) quality control within and between laboratories. This latter point has been emphasized repeatedly as a priority item, but funding practices by federal agencies generally paid scant attention to this problem until a few years ago. The 1975 NRC report called attention to this, and recently the American Chemical Society (ACS) has issued guidelines for data acquisition and data quality evaluation in environmental chemistry (Keith et al., 1983), which address this fundamental issue for all types of environmental analytical chemistry. The current status of quality control and laboratory intercomparison is not yet adequate to accomplish detailed comparisons of data sets from different laboratories or to be sure which specific chemicals in various petroleum fractions are responsible for observed effects. Generally, only compar isons of qual itative trends or large differences of factors of 10 or more are valid within quality control or inter- laboratory comparison experiences proof to 1979-1980. Although progress has been made, much more needs to be accomplished. Two major developments in our knowledge of inputs, fates, and effects of petroleum in the marine environment since the 1973 litera- ture review for the 1975 NRC report have an important bearing on

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95 analytical chemistry considerations. First, studies of polycyclic aromatic hydrocarbon sources and fates over the past ~ O years have increased markedly and have revealed the global significance of chronic low level polynuclear aromatic hydrocarbons (PAM) inputs related to the incomplete high temperature combustion of fossil fuels. In many cases, analytical methods must try to distinguish between petroleum PAR inputs and pyrogenic PAH inputs. Second, present evidence substantiates a concern expressed in the 1975 NRC report that petroleum hydrocarbons readily undergo structural alterations by photochemical and biochemical metabolic oxidation. Postspill analytical programs based only on hydro- carbon measurements in seawater, sediments, and tissues cannot measure an important set of transformation products. Acute needs have developed (1) to manage data and make them acces- sible (needs that have only occasionally been addressed in specific programs), (2) to evaluate existent data much more thoroughly to enable future efforts to be more targeted, and (3) to link divergent analytical developments. This latter concern arises from the fact that varieties of analytical techniques are being separately developed for petroleum chemistry research, marine chemistry research, forensic applications (e.g., U.S. Coast Guard techniques!, general environmental chemistry research, and environmental regulatory or surveillance (e.g., U.S. Environmental Protection Agency (EPA) priority pollutant) methodologies. An overview of the literature confirms this and raises concerns that, in our efforts to monitor the environment, the methods being developed for and information derived from the various programs are diverging. This is apparent in the groups of marine chemistry and other environ- mental chemistry literature, citations from one omitting relevant literature from the other. Regulatory definitions of petroleum hydrocarbons must be more firmly based in current knowledge of the composition of petroleum inputs, fates, and effects in the environment. The review of analytical techniques, methods, and strategies that follows has drawn from marine and nonmarine analytical chemistry and organic biogeochemical studies alike. Due to the great pool of recent literature, attempts have been made to include mainly post-1975 litera- ture unless only pre-1975 information Is available. AS no single literature reference comprehensively covers many of the topics dis- cussed, a number of references are cited in many cases. Several recent reviews have aided in this preparation and should be consulted for additional details: Petrakis and Weiss (1980), R.C. Clark and Brown (1977), Farrington et al. (1976a, 1980), R.A. Brown and Weiss (1978), Pancirov and Brown (1981), and Malins et al. (1980~. SAMPLING AND SAMPLE PRESERVATION The nature and the quality of information derived from marine environ- mental samples are dependent on the quality of sampling methods used and the care taken in utilizing these methods. Of primary concern in both petroleum hydrocarbon baseline and oil spill samplings is the avoidance of sample contamination and cross contamination. R.C. Clark and Brown (1977) presented details of quality assurance aspects of collection techniques, which included attention to the cleanl iness of

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96 sampl ing dear ices, subsampl ing implements, and star age conta iner s and the exclusion of field (shipboard) contaminants from the samples. Details of collection methods of seawater, sediments, biota, and waterborne oil samples were presented in R.C. Clark and Brown ~1977) , D.R. Green (1978), and ASTM Method D 3325-78. Sampling strategies have been developed for each spill scenar lo, and usually provide for pre- impact (baseline) and postimpact samplings, reference samplings (unimpacted sites), and a postspill time series to examine details of recovery (e.g., Boehm et al., 1981b; Atlas et al., 1981; Teal et al., 1978; Burns and Teal, 1979; Keizer et al., 1978) . Sediments Recent laboratory and f ield studies have revealed new, important subtleties related to sediment sampling, both in spill and nonspill situations. Gearing et al. (1980), in controlled experiments, and Boehm et al. (1981b) , in a field assessment, pointed to the importance of sampling newly deposited hydrocarbon-bearing sediment (i.e., floe) in oil spill studies. Thompson and Eglinton (1978b) showed that different particle sizes and types within a given sediment have differing hydrocarbon compositions. Determination of petroleum and PAR chemical composition associated with dif ferent types and sizes of sediment particles may yield important information on availability of certain compounds for biological uptake in benthic communities. A variety of sediment samplers has been used to obtain "surface sediment. These include box corers, which are most useful in soft bottoms and acquire a relatively undisturbed core of sediment; grab samplers (e.g., Smith-MacIntyre and Van Veen), which are useful in all sediment types, but may be subject to sample washout in gravelly or shelly sediment; gravity corers, which utilize a core liner (polyear- bonate) to obtain a cylindrical core of sediment which may be subdivided for analysis; hydrostatically damped corers in multiple arrays (Pamatmat, 1971; Wakeham and Carpenter, 19761, which have damped rates of sediment penetration; sediment boundary layer suspension (floe) collectors (Bryant et ale , 1980~; diver and other manual collectors (Atlas et al., 1981; D'Ozouville et al., 1979~. The selection of the sampling device is dictated by the sediment type being sampled and the informational needs of the particular program. Sediment Traps The design of sediment traps to ensure efficient collection and postcollection preservation of sedimenting material is an area of intense research and debate (e.g., Wakeham et al., 1980; W.D. Gardner, 1980; Jannasch et al. , 1980~. Traps have been utilized to examine the fluxes of suspended organics, including hydrocarbons, to open ocean and coastal sediments. The deployment of unsophisticated sediment traps in spill situations has provided critical information on the fate of

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97 spilled oil (Boehm et al., 1981b; Johanssen et al., 1980; Boehm and F lest, 1980a) . Mar ine Organisms A var iety of sampling devices exists for the collection of pelagic and benthic marine organisms (R.C. Clark and Brown, 1977; Grice et al., 1972 ~ . These include plankton nets, trawls, and dredges of var. fed design (see Biological Methods section). Extreme care must be taken to avoid sample contamination from the sampling device, from the ship and ship's discharges, from the sample containers, and from oil in the water column. For example , collection of uncontaminated pelagic biota samples from a ship during a spill event is very difficult, and it is difficult to distinguish ingested from external oil (American Petroleum Institute, 19771. Diver collections are preferable in these cases. Again, the choice of sampling device and the sampling design depend on the nature of the organism and the program's statistical design. For example, in order to examine the relation of oil in the sediment to its bioaccumulation in benthic organisms, animal samples should ideally be obtained in close proximity to the sediment sample, with either divers in subtidal areas or manually in intertidal areas, and from the same sampling device (e.g., box corer). A n sample ~ of mar ine organisms for analyses is def ined by both analytical and statistical considerations. An estimated 1-10 g dry weight (100 g wet) are usually needed for prespill analysis and for spill-impacted samples to achieve analytical detection limits. However, the optimum sample size (i.e., number of organisms per sample) is dic- tated by several considerations, including whether information on a population at a certain station is required, or knowledge of individual- to-individual variation is desired (Boehm, 19781. Seawater Sampling of seawater to obtain information on hydrocarbon levels, in both baseline and spill-related samples, is the most difficult of samplings due to (1) the potential for contamination from the surface film (Gordon and Keizer, 19741, (2) the potential for contamination from the sampling device (Boehm and Fiest, 1978; Zsolnay, 1978a) or from associated rigging and the sampling ship or platform, and {3 possible problems with compar ing data from samples obtained with different sampling devices (Levy, 1979a; Boehm, 1980a). Use of the various available devices for obtaining seawater samples for petroleum hydrocarbon determinations has been reviewed recently by D.R. Green (19781. Examples of the problems encountered are contamina- tion by certain plastics and "O. rings. In addition, accumulator systems (e.g., octadecylsilicic reversed phase adsorbents [May et al., 1975; Eisenbeiss et al., 1978; Saner et al., 19791, XAD-2 macroreticular resins [Ehrhardt, 1978] , and polyurethane foam [e.g., deLappe et al., 19801) have been used with varying results to concentrate hydrocarbons

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98 on solid phases. Alternatively, large volume water samples (10-90 L), which pass through the surface in a closed position, must be used to achieve analytical detection 1 imits which allow sub-part-per-billion ~ug/L) levels of hydrocarbons to be detected (e.g., deLappe et al. , 1980; Boehm, 1980a; Farrington et al., 1976a) . Chester et al. (1976) and Keizer et al. (1977) utilized simple devices to obtain 4-10 L of sample using glass bottles which manually open below the surface. Recently, pumping systems have been applied successfully to the subsur- face measurement of petroleum in the water column below surface oil slicks (Fiest and Boehm, 1981; Boehm and Fiest, 1980b; McAuliffe et al., 1980; J.C. Johnson et al., 19781. The use of discrete versus continuous sampling systems is dictated by the sampling scenario. Continuous pumping systems can be used for separation of dissolved and particulate water column samples (Ehrhardt, 1978; Goutz and Saliot, 1980; deLappe et al., 1980; Boehm and Fiest, 1980b), although water from discrete samplers can be pressure filtered through glass fiber filters (Boehm, 1980a; J.R. Payne et al., 1980a). Ehrhardt (1976, 1978) and deLappe et al. (1980) describe continuous seawater pumping systems which pass large volumes of water through in-line glass fiber filters upstream of XAD-2 resin and polyurethane foam. Dissolved and particulate size fractionations are important in discerning the fate and pathways of biological uptake of spilled oil (Zurcher and Thuer, 1978; Boehm and Fiest, 1980b) and distribution of petroleum hydrocarbons in seawater in nonspill studies (Goutz and Saliot, 1980; Boehm, 1980a). However, the terms "dissolved and ~particulate" are operational in nature due to possibilities of passage of colloidal-sized particles through the filter and the likelihood of changing the pore size of the filter as filtration proceeds. Sampling for Low-Molecular-Weight Hydrocarbons Samples (sediment, seawater, biota) to be analyzed for low-molecular- weight hydrocarbons require special handling. After collection, water samples should be treated to avoid agitation or inclusion of air bubbles in storage bottles. Water samples should fill sample bottles and be sealed with a Teflon cap, leaving no headspace, and be refrigerated until analysis proceeds (Brooks et al., 1980~. Sediment samples should also fill sampling containers and they should be frozen. Alternatively, sediments can be transferred immediately to containers holding "poisoned {e.g., sodium azide) hydrocarbon-free seawater, the container headspace flushed with helium or nitrogen and the container inverted at near-freezing temperature (Bernard et al., 19781. Biota samples should be frozen until subsampled for purgeable organics (Environmental Protection Agency, 19801. Sample Preservation There is a general lack of information on the longevity of petroleum hydrocarbons in stored, unextr acted samples of all types. Thus, the

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99 procedures descr ibed are based, in most cases, on first principles, with r egard to minimiz ing processes that will alter the compounds of interest. All samples (sorbents, filters, sediments, tissues) should be frozen at -10 to -20C after collection. Water samples, however, are impractical to freeze and can be solvent extracted aboard ship or preserved in the dark with a bacterial retardant (chloroform, methylene chloride, mercuric chloride, sodium aside). However, care should be exercised in the choice of preservation technique. Samples obtained for multiple use in chemical and biological studies should be preserved in a manner that does not mitigate against certain measurements; e.g., sodium aside would not be acceptable for samples to be used in a variety of biochemical or physiological studies. Volatilization of hydrocarbon components and microbial and photochemical oxidation of organic matter in samples are the primary concerns to be addressed in postsampling preservation. ASTM Method D 3325-78 presents a standard method for storing waterborne oil samples. The effects of long term (months to years) storage of samples under "preserved conditions is largely unknown, although Medeiros and Farrington (1974) determined that, after 18 months of storage of oil-spiked cod liver lipid extract, analytical results for some major hydrocarbons were unchanged. SP TLLED OIL CHARACTERI ZATIONS As the behavior and environmental fate of spilled oil are dependent on the physical and chemical properties of the oil and the meteorological/ oceanographic conditions, there is a need for full character ization of an authentic sample of the source of oil and a ser ies of oil samples from the water's surface and from oiled beaches. These oil samples will serve as reference materials for environmental analyses and also may be used in damage assessment studies and in judicial proceedings. In addition, rapid analytical information should be obtained during of Ashore spill scenar ios to predict the physical, chemical, and toxico- logical properties of oils after being waterborne and as they may impact sensitive shorelines. Offshore and shoreline countermeasure strategies often hinge on the knowledge of the physical properties of spilled oil, actual and predicted. Sample Collection and Preservation The original 1975 NRC collection guidelines should be adhered to and supplemented by ASTM Methods D 3325-78 and D 3694-78, U.S. Coast Guard ( 1977 ~ considerations of collection, sample documentation, and chain-of-custody procedures, and sample preservation. Several authentic cargo samples should be collected in all cases along with waterborne oil samples. Replication is important, as floating oil patches exhibit significant heterogeneity. If possible, floating oil patches or slicks should be marked with buoys and sampled periodically until dissipation or landfall . Samples should be taken

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100 from small boats or helicopters, as it is often impractical for large ships to enter large oil patches. Cross-contamination should be avoided, especially while sampling in areas of heavy contamination wherein gear and clothing may become oiled. Gloves, protective clothing, and activated charcoal trap respirators should be used while working in heavy oil, and personnel should be monitored by a trained medical stat f . The samples should be taken in suf f icient quantities to permit replicate physical and chemical analyses. One hundred milliliters of sample are needed for some physical tests (e.g., viscosity), so wherever possible, liter-sized jars should be filled with sample. Sample documentation should be made on prespecif led, durable, water- proof tags (e.g., U.S. Coast Guard, 1977) to include information on collection location, date, time, name of collector, and sampling device. All collections should be logged in a master log and given a unique sample number . Consecutive number ing National Oceanic and Atmospher ic Administration, 1980 ~ us ing collector codes has proven extremely efficient in sample collection operations, and avoids ambiguous situations which occur during all collections when several people or groups are sampling concurrently. Preservation of oil samples involves the containment of low boiling components and the retardation of degradation through postsampling photochemical and microbial degradation. Analytical Methods Physical and chemical information should be obtained as soon as possible after the spill occurs. Field Information The existence, extent, and mapping of subsurface oil concentrations may be acquired during spill events through the use of in situ (towed) fluorometers (Environmental Devices Company, 1977; Calder et al., 1978) or continuous pumping through shipboard fluorometers (e.g., Boehm and Fiest, 1980b). Several important physical measurements, such as the determination of water content of oil {i.e., emulsification state) and the specific gravity of oil, can be made using simple devices (National Oceanic and Atmospheric Administration, 1977~. This information is valuable to countermeasure strategies (i.e., use of dispersants, application of booms, estimations of cleanup efficiency). Laboratory Information (Short Time Frame: Days to Weeks) Samples shipped to the laboratory should be subjected to a series of routine physical property tests to determine the oil's characteristics and behavior. These include accurate specific gravity, viscosity, pour point, and fractional distillation temperatures. ASTM procedures exist

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101 for all of these measurements (R.C. Clark and Brown, 19771. In addi- tion, useful parameters associated with the emulsification process are the asphaltene and wax contents of whole oil. Ideally, chemical testing in the laboratory should include class separation to obtain information on the initial and changing relative proportions of saturated hydrocarbon, aromatic hydrocarbon, and polar and asphaltic fractions. Oils should initially be dissolved in methyl- ene chloride, or s imilar solvent with water r emoved by phase separ at ion and drying over sodium sulfate. The extract is then deasphalted by precipitation by pentane addition (ASTM Method D 893-80), and a portion of the pentane is charged to and elated on silica gel, silica gel/ alumina, or other column (see Measurements and Detailed Analysis of Environmental Samples section). A class separation and characterization sequence based on initial normal phase high pressure liquid chromatog- raphy (HPLC) (equivalent to silica gel column chromatography) followed by detailed capillary GC analysis (Gas Chromatography section) and analytical HPLC (High Pressure Liquid Chromatography section) has been described by Crowley et al. (19801. Laboratory-derived data should include GC analysis, preferably capillary GC, of the hydrocarbon fractions so as to determine the boiling range and overall composition of the oil. Laboratory Information {Long Time Frame: Weeks to Months) Techniques of petroleum character ization include those that der ive detailed compositional information as well as those that obtain information used to match waterborne oils with suspected cargoes through TR (infrared spectrometry), W/F (ultraviolet fluorescence spectrometry), GC (gas chromatography), FID (flame ionization detector) element specific detectors, and trace metal (Ni/V) measurements (U.S. Coast Guard, 1977; ASTM Methods D 3415-79, D 3414-79, D 3650-78, D 3328-78, D 3327-79) . Gas chromatography with f lame ionization and sulfur- or nitrogen- specif ic detectors yields considerable information on the molecular weight range of hydrocarbon components, and is one of the more powerful methods for broadly characterizing crude oils (Crowley et al., 1980; Rasmussen, 1976; Clark and Jurs, 1979) and refined products (e.g., Ury, 1981~. Graphical plots of the relative saturated and aromatic compo- sitions of oil samples (Patton et al., 1981; Atlas et al., 1981; Boehm and Fiest, 1980b) complement specific calculated parameter ratios in descr ibing the oil's chemical properties. IR measurements, in addition to having forensic use, can be used to characterize major compound groups and to evaluate weathering in a gross way by the appearance of carboxyl and hydroxyl functional groups (Rashid, 1974; Blumer et al., 1973; W.E. Reed, 19771. Mass spectrometr ic (MS) class and group (or subclass) analyses pro- v icing quantitative information on some 25 molecular types have proven very useful in compar ing oil types and in readily evaluating the chemi- cal character istics of fresh and weathered oils (Robinson and Cook, 1969; Petrakis et al., 1980; ASTM Method D 2786-71~.

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102 GC/MS techniques have been used to identify fresh and weathered oils based on detailed compositions (Hood and Er ickson, 1980; Albaiges and Albrecht, 1979; Atlas et al., 1981; W.E. Reed, 1977; Calder et al., 1978; Overton et al., 1980b; DeLeon et al., 1980; Schmitter et al., 1981) . HPLC is another technique for character iz ing oils on the teas is of their aromatic hydrocarbon content (e.g ., Crowley et al ., 1980 ~ . A combination of IR and HPLC analyses, to quantify and characterize saturated and aromatic petroleum hydrocarbons, respectively, has been used in conjunction with Go for analysis (Riley and Bean, 19791. Further long-time-frame characterizations of spilled oils include the techniques of carbon and sulfur isotope ratios (Koons et al., 1971; Hartman and Hammond, 1981; Sweeney et al., 1980), proton and 13C nuclear magnetic resonance spectroscopy {Petrakis et al., 1980), and elemental (C, H. N. S) analysis (e.g., W.E. Reed, 1977; National Research Council, 1975~. Additionally, many of the analytical techniques used by petroleum chemists may effect more detailed char- acterizations (Terrell, 1981~. Examples of detailed multiple-technique characterizations of oils are given by W.E. Reed (1977) for weathered tars, W.E. Reed and Kaplan (1977) for marine petroleum seeps, and Overton et al. (1980b) for Ixtoc I oil. MEASUREMENTS AND DETAILED ANALYSIS OF ENVIRONMENTAL SAMPLES Gener al The analysis of a particular sample of water, sediment, tissue, air, etc., for petroleum hydrocarbons must be preceded by matching the particular informational need with the proper analytical technique. For example, information may be needed on the gross amount of oil in the dosing system of a toxicological study or on concentrations of an individual aromatic toxicant (e.g., naphthalene) and its metabolites (e.g., naphthol) in a marine fish. Single analytical techniques (e.g., W , GC) can be used for certain applications when the analyt ical end is to examine absolute levels or compound assemblages (nonpoint sources), but multiple techniques (e.g., W + GC ~ IR) are required for forensic purposes in matching environ- mental compositions of petroleum to specific point sources. Figure 3-1 illustrates various analytical options for environmental samples. The proper choices of separation and analytical techniques are at the heart of environmental petroleum hydrocarbon chemistry. In general, the less chemically specif ic techniques require less sample processing and manipulation. With increased processing, the level of analytical detail, and hence compositional and quantitative information, increases. The field of oil pollution chemistry has expanded rapidly in the past 5-10 years without great attention to intercomparabil ity of measurements between different laboratories using similar techniques and between different analytical techniques used to generate data. The generation of analytical data continues at a rapid pace at different

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103 SAMPLE 1.) PRETREaTMENT (DRYING, IdOMOGENIZATION, e I l 2.) EXTRACT WITH SOLVENTS SUBSAMPLE FOR VOLAT I LE HY DROCARBON S GAS STR I PP I NG GAS EQUI LlBRiUM Dl RECT I NJ ECT I ON PU RG E AN D TRAP G C , ~ H IGH L IPI D SAMPLES 1.) SAPON I f I CAT I ON 2.) aLUMINA PRE COLUMN SAPONIFIED LIPI DS - T OT A L NON - SAPON ~ f I ABLE ORGAN I CS 1 F3 POLAR FRACT I ON S TLC HPLC GC2/MS | SATURATES | r ~ ~, STRA I G HT BR~ ~E D 2 ~! ~ CY~Ll C GC ~Gr 2 le. ) ~, ~ . | TOTAL EXTRAC~L_~= GRAViMETRIC (Oil ~ Grease) ORGAbJ I C S - ~ UV/ F LOW LIPIt) SAMPLES POLAR ITY SE PARATIO \IS 1.) COLUMN OR TH IN LAYER CHROMATOGRAPHY ( Florisil, Silica Gel, Clay) . ~ HYDROCARBON FRACT IONS - GRAVIMETRY _ - GC2 - GC 2/~s ~IZE SEPARATION | | MOLECULAR SIEVES | ARO MAT~ OLEF I NS . . GRAV I M ET R Y I R UV / F GC2 GC2/i'S S I ZE SEPARATION - GEL PERMEATION - CHROMATOGRAPHY , HPLC or SEPHAC)E X) ( | OLEFINS 1 | AROMGTICS | 1 F21 1 GC2 GC2/MS FIGURE 3-1 Analytical options for analysis of petroleum compounds in sediment, tissue, particulate matter, and water. levels of sophistication. Recently the ACS Subcommittee on Environ- mental Analytical Chemistry published its "Guidelines on Data Acqui sition and Data Quality Evaluation,~ which expressed three interwoven strategies of modern trace analysis: (1) the development of sensitive, specific, and validated methods; {2) the use of protocols that describe

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104 the details of the measurement process and sampling procedures; and (3) the use of quality assurance procedures to monitor the quality of the data as it is developed. At the heart of all data generation should be procedures of rigorous quality assurance including routine determina- tions of procedural blanks, instrument calibration and standardization, analytical precision on replicates, recovery of spikes, detection limits, and comparison of results with other laboratories (intercalibra- tions) {MacDougall and Crummett, 1980~. These guidelines should become part of all petroleum hydrocarbon studies. In addition, the precision of environmental analytical measurements has three components: (1) instrumental variation (replicate analyses of the same solution), (2) analytical variability (analysis of replicates of the same homogenate, or subsamples), and (3) sampling variability (replicate analyses of sampling replicates). Numerous methodologies have been used in conjunction with oil pollution studies, and the efficacy of the various methods used, for example, in extracting and fractionating organic matter from sediment and in performing detailed analysis of hydrocarbons, has only recently (since 1975) come under rigorous study through both intralaboratory experiments and thorough intercalibration exercises. Extraction of Organic Matter (High Molecular Weight, Cll+) Hydrocarbons Sediments Several different solvent extraction methods are commonly used for the extraction of petroleum hydrocarbons from sediments. No standard method exists, but most methods involve the combined use of polar and nonpolar solvents to effect an efficient extraction of organic matter. Geochemical and oil spill sediment samples differ in the ease of extraction of hydrocarbons from the sediment matrix, the latter containing loosely bound petroleum hydrocarbons. Thus while one of the rigorous extraction procedures is necessary to extract, for example, low to moderate levels (less than 10 ug/g) of PAH from a s~lt/clay sediment, simpler techniques may suffice for spill samples. As it is often important to discern levels of incremental addition of low to moderate levels of oil to sediments containing some prior history of anthropogenic pollution, the rigorous solvent extraction methods (e.g., Soxhlet, tumbler/shaker) are most appropriate for all environmental samples. Sediment extraction techniques include organic _ solvent extractions (e.g., D.W. Brown et al., 19801, alkali digestions followed by solvent extractions (Environmental Protection Agency, 1980; Farrington and Tripp, 1975), headspace gas stripping (May et al. , 1975) , and steam distillation (veith and Kiwas, 1977; Bellar et al., 1980) . Solvent extractions employ (1) the use of the Soxhlet extractor with a com bination of polar and nonpolar solvents (e.g., Hites et al. , 1980; Farrington and Tripp, 1975; Lake et al ., 1980 ; Environmental Protection Agency, 1980), (2) the reflux of sediment with organic solvents (e.g.,

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124 monitoring programs, and (3) standard certified reference materials. The most significant intercalibration exercises presently underway or previously undertaken address type (1) exercises, involving enough laboratories to enable statistical analysis of data. Type {3) materials with National Bureau of Standards (NBS) certification, containing known amounts of specified constituents, have been requested by scientists in environmental studies. To date, only one such sample has been prepared, due to uncertainties of sample homogeneity, storage stability and matrix ef feats, and definitive analytical methods. A new standard reference material (SAM 1580), "Organics in Oil Shale,. is intended primarily for evaluating reliability of analytical methods for the determination of three PAR and two pl.~.enolic compounds in an oil matrix. Thus, most exer- cises involve type (2) programs. A summary of major petroleum hydro- carbon intercalibration studies undertaken in the 1976-1981 period is shown in Table 3-2. Interiaboratory precision has improved signifi- cantly over the past 5 years or so, as techniques for both analyzing samples and running intercalibration exercises have improved. The roots of a well-conducted intercomparison program lie in the homogeneity of the sample and the comparability of data (i.e., the reporting of the same components by all participating laborator ies on the same basis, corrected for recovery) . Dur ing the last 5 years, the ability to conduct intercalibration exercises and to analyze samples rigorously and achieve comparable results have both improved markedly. Bearing in mind that there is no fright answer" in such exercises using environmental samples, a group of laboratories in the United States has obtained generally tightly grouped results based on GC2 {and GC2/MS) determined alkane and polynuclear aromatic hydrocarbon levels in sedi- ments (MacLeod et al., 1981a). While statistical evaluations are still in progress, laboratories probably can achieve comparable (within a factor of 2 and often much better) analytical results. Coefficients of variation for individual aromatic hydrocarbon determinations in the Duwamish II study were, for example, +14% for fluorene, +17% for phenanthrene and fluoranthrene, and +39% for perylene, for the six data sets (MacLeod et al., 1981a) and were as good for n-alkane values. The International Council for the Exploration of the Seas (ICES) intercalibration studies, while not as rigorously controlled as the Duwamish exerc ises ~ see Table 3-2 ), have yielded compar able f luor es- cence-based data on sediments with a coefficient of variation for "total petroleum" in the 10-308 range. This level of agreement was reached by using specified quantification methods, i.e., prescribed Integrated Global Ocean Station Systems (IGOSS) wavelengths. The ICES-sediment exercise yielded comparable W-, OR-, and GC-based Total hydrocarbon. concentrations. Intercalibrations on biological mater ials have posed more serious problems, with even W-based data (ICES study) yielding poor results, probably due to both analytical problems and quantification techniques. The GC- and GC/MS-based EPA megamussel study currently under way (no f inal data available) specifies individual compounds and aromatic isomer ic groupings for reporting. The emerging view appears to be that, for the most part, comparabil- ity of petroleum hydrocarbon and PAM results is beginning to depend

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127 q~ 1 0 C) o . - o ~. - o ~ o C tU ~- 4> 3 _ C ~ c tn 0 ~c :' O ~ C V a,, . - a' c u' ~ rG E ~ ~ - - 0 3 0 ~a, n tn 0 ~ ~ ~ t) _ 0 U] 3 -4 ~ ~ ~ ~ ~ 4~ O ~O ~ ~ X O C .c lll ~o :>~ + 1-- ~ ~ u~ E ~t~ ~ -~: V C 1 1 1 o CD 3 _ C O ~ ~ - a a 4 - n ~o ' ~ a' - C JJ ~: C ~0 E Q 3 Q. O O O C) ~ -I 4 3 ~a) 3 .= Ll ~ ~ t: ~ ~ eq O ~ ~ - - C L. C) O `: E~ ~ P~ - . . ~m r4 ~ t) 0X s ~ ~ s _ - ~ ~ ~ ~ V _ ~ ~`: 0 ~4 3 ~ ~ X t) O C O ~ ~ -4 ~ O ~ ~P. ~. ~ ~ ~ ~ ~ ~ - - go~ ~ X ~ ~ - Y ~ C eg' ~ ~ ~ ~ .- ~ ~ o~ ~`: 3~ ~ `24 3 L' ~ ~ ~ ~ ~_ 1 ~ ~ ~ {~) 1 ~ oo ~ 1 c o ~s: E ~4 P4 0 U) ~S Z a, U] :s E u~ E~ ~: ~O c. ~a ~ Q. ~n ;^ o - c z

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128 more on the quantification process ~ i .e ., how individual component GC peaks are quantified) than on the extraction and process ing steps (i.e. , several extraction procedures will suffice). This is true for the Duwamish I and II sediment studies, wherein differing extraction methodologies were used (D.W. Brown et al., 1980; MacLeod et al., 1981a), and may be emerging as the reason behind variability in the more difficult, interference-prone biotic measurements. Clearly, further intercomparisons are required, addressing (1) comparability of results based on simpler, more universally available methods (i.e., W fluorescence), (2) comparability of more rigorous techniques (i.e., GC and GC/MS), (3) intercomparability of the methods, and (4) the location within the analytical technique for discrepancy. Laboratories should be urged to participate in intercalzbration pro- grams in a nonthreatening atmosphere at the start of the environmental chemistry program, to enable the refinement of analytical techniques so as to achieve results within a determined statistical range. The NBS SRM oil shale, samples such as Duwamish I and II sediments, and the ICES sediment appear to be most appropriate for this purpose. REMOTE DETECTION AND MEASUREMENT OF OIL SPILLS Remote sensing devices used to monitor marine pollution are becoming more sensitive and reliable than they were just 5 years ago. The use of both airplanes and satellites as platforms for remote sensing devices has been explored. ICES and NOAA, as well as other organiza- t~ons, have been involved in the development of satellite-carried equipment for sensing oceanographic parameters (Apel, 1978; Kniskern et a-l., 1975; Koffler, 1975; N.R. Anderson, 1980; Klemas, 1980~. However, satellite monitoring is not without problems. Geosynchronous satellites do provide repeatable coverage, but the resolution is not great enough to be of practical use. The NASA ad hoc committee on remote sensing concluded that the physical parameter requirements for oil spill monitoring are at least an order of magnitude greater than the remote sensing data which are now available {Croswell and Fedors, 1979~. In addition, Goldburg (1979) concluded that sensors in airplanes are more feasible and cost efficient than satellite remote sensing, thus, the focus on airborne sensors in this section. The U.S. Coast Guard has developed remote sensing "packages to aid in the detection of oil slicks. The two prototypes of the current package, AOSS I and AOSS II (Airborne Oil Surveillance Systems ~ and TI), are described more fully in Bentz (1980), Maurer and Edger ton (1975), and G.P. White and Arecchi (1975~. The third-generation aerial reconnaissance system, designated AIREYE {for aerial remote instrumenta- tion), will be installed in Falcon 20-G jet planes and includes side- looking airborne radar (SLAR,, an IR/ W scanner, a computerized data recording system, and an aerial reconnaissance camera (N.R. AndersOn, 1980~. By including sensors utilizing three portions of the electro- magnetic spectrum, the number of false alarms due to kelp beds, wake scars, and the weather can be kept to a minimum (J.R. White et al., 19791. .

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129 Remote sens ing devices can be divided into two categor ies: those based on passive (natural) reflectance and emission of some part of the electromagnetic spectrum, and those based on an active (man-induced) electromagnetic excitation of the ocean sur face and the collection of reflected radiation. The passive group includes microwave, IR, and W collectors. Those devices that depend on man-induced electromagnetic radiation include radar, W fluorescence systems, and laser backscatter sensors. Table 3-3 (from N.R. Anderson [1980] and Maurer and Edger ton [19751) reviews the types of remote sensing devices and the false alarms g iven by each. Passive microwave systems measure radiation waves naturally emitted or reflected by the sea surface. Microwave brightness is a function of surface roughness and the dielectric constant of the surface. Thin oil films have a calming effect on the water surface, which results in a modification of the microwave structure and thus a lower brightness temperature. Thick films (~0.1 mm) emit more microwave energy than unpolluted water does; thus, the film thickness can be determined from the relative brightness temperature. Passive microwave systems can penetrate weather and are independent of lighting conditions. Disad- vantages include coarse resolution and a limited swath (Maurer and Edgerton, 1975~. Infrared sensors detect apparent temperature differences between oil and water due to the physical properties of the two substances. Oil and water have different reflectance properties in the 2- to 4-pm spectral range (G.P. White and Arecchi, 19751. In the near IR range (0.6-1.1 um), the radiance from an oil slick is 20-100% greater than the radiance from water, and at night, oil gives 50% greater radiance than water does (Catoe, 1972~. Thermal IR (1.1-14 um) sensing is limited to specific atmospheric windows where the atmosphere is trans- parent enough to allow the waves to pass through without significant absorption (Catoe, 1972~. Thermal infrared sensing can also be used 24 hours a day, and IR waves can penetrate haze but not clouds. Odd local thermal structures {e.g., an upwelling) can cause false alarms (Maurer and Edgerton, 1975~. Passive ultraviolet collectors can detect oil patches because oil reflects more W light than water does. The greater amount of W radiation that water absorbs, the cooler it appears in relation to the oil slick it surrounds. Passive W collectors require some ambient sunlight, but the light range can be extended if the collector is used in conjunction with a low light level television (LLLTV). False alarms from this system include kelp patches (Maurer and Edger ton, 1975), and atmospheric aerosols limit its use in hazy weather (Catoe, 19721. One of the more widely used active sensing systems is radar. It is used with a great deal of success to detect offending ships and oil slicks on the sea surface. SLAR has a swath of up to 80 km (40 km on each side of the airplane). SLAR detects the capillary wave-damping effect caused by oil on the sea surface, so this technique becomes ineffective on flat, calm or extremely rough seas. Another disadvantage of SLAR is that it does not "see" a strip directly beneath the plane. An IR/ W line scanner is often used to overcome this problem (J.R. White et al., 1979).

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130 TABLE 3-3 Oil Spill Detection by Remote Sensing: Sensors and Spectral Regions Sensor Spectral Approach Region Active reflectance Microwave radar, 1.05-5 cm Laser backscatter W fluorescence, 0.4 m Passive W , 0.4 m reflectance Visible 0.4-0.65 m Near IR, 0.65 m Passive Thermal IR, emission 3-14 m Microwave, 0.2-1 cm False Alarmsa Natural organic slicks Wind slicks, ship wakes Pollutant organic slicks (detergents, sewage sludge) Kelp/debris Dense cloud cells Unrippled water under calm conditions Natural organic slicks Suspended sol ids Natural organic slicks Pollutant organic slicks Suspended sol ids Shallow water Broken cloud deck Natural organic slicks Other pollutant slicks Natural organic slicks Pollutant organic slicks Ship wakes Thermal discharges and effluents Upwelling Foam patches Kelp/debris Dense cloud cells Has all of the listed sensors detect oil on water, natural petroleum seeps would be a false target for each sensor. SOURCE: N.R. Anderson (1980) and Mauer and Edgerton (1975). A laser backscatter sensor (Dichromatic Lidar Polarimeter), which transmits at two coaxially aligned, vertically polarized wavelengths, has been developed (G.P. White and Arecchi, 1975) . Depolarization occurs at the sea surface, and the two wavelengths are backscattered differentially. The backscatter is collected, and the magnitude of returned radiation and the depolarization ratios are used to determine the presence of oil. Hoge and Swift (1980) used a laser-induced water

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131 Raman backscatter sensor to detect the presence that oil depressed the Raman backscatter, which of oil. They found r eturned to normal after the sensor was over water once again. Oil film thickness could also be determined using this method . Probably the most promising remote sensing device currently being developed is the laser-induced W fluorescence sensor. Laser-induced fluorescence systems not only differentiate oil from water but also can discriminate between oils as well (Kim and Hickman, 1973; Rayner et al., 1978; Fantasia et al., 1971; Fantasia and Ingrao, 1973; Horvath et al., 1971; O'Neil et al., 1975; Measures et al., 1975; Rung and Itzkan, 19761. A W laser excites the sea surface, and the fluorescence return ~ s collected. A photomultiplier tube converts the fluorescence to an electrical signal, and then a fluorescence spectrum can then be printed out. Field trials by Fantasia et al. (1971), Horvath et al. (1971), and Rayner et al. (1978) have shown that, not only can oil fluorescence be detected over background fluorescence, but oil can be classified into three groups: diesel fuel, crude oil, and bunker fuel. O'Neil et al . (1980) reported that oil shows increased W absorbance with decreasing excitation wavelength; thus, thinner oil layers can be detected. The shorter wavelengths also show greater structure in the fluorescence spectra, which gives greater discrimination power and allows c lass if ication of d if fer ent o its . Attempts have been made to detect oil in the water column using W fluorescence sensors. These have been almost totally unsuccessful because there is so much nonpetroleum suspended organic matter in seawater and, because water absorbs so much W light, there is very little fluorescence emitted (F.E. Hoge, personal communication, 1981) \ MONITORING FOR PETROLEUM HYDROCARBONS The success of any monitor ing program depends on the proper selection of environmental parameters to be measured, the proper choice of analytical techniques to be used, the comparabil ity of analytical results over time and between labor ator ies, and the statistical validity of the measurements (i.e., what level of sampling and analytical effort will detect change) (Risebrough et al., 1980~. also the Introduction to this chapter.) When the amounts of oil are large, simple analytical techniques (e.g., IR, gravLmetry) or remote sensing may suffice. However, at low levels, analytical strategies become critical. A specific property of the oil such as W/F may be determined and "equivalent oil concentra- tions" obtained. Alternatively, individual components in a single class of compounds (e.g ., aromatic hydrocarbons) may be quantif led. Measurements of specific properties, although more widely performable by more laborator ies, rely on tenuous assumptions regarding cal iteration of -the methods . Monitor ing of individual compounds is more expensive and requires extensive quality control and intercalibration. However, much useful information for dif ferentiation between hydrocarbon sources can be obtained, along with determination of the extent and severity of .

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132 pollution. If seawater is the targeted environmental compartment, then W /F may suffice due to low background levels. In cases where correla- tion analysis of hydrocarbon and other parameters is used as a monitor- ing tool' then these simpler techniques may differentiate impacted from nonimpacted sediments (Boehm and Quinn, 1978~. However, most monitoring scenarios call for specific chemical component measurements, perhaps guided by specific property techniques {see Figure 3-3~. Several far-reaching analytical monitoring programs have been initiated in recent years which address two main concerns: (1) detection of environmental change (i.e., environmental degradation or improvement) due to petroleum hydrocarbon (and other pollutant) inputs to the system, and (2) assessment of the temporal recovery of an oil spill stressed system. A third concern only loosely being addressed due to constraints of time and data handling is the identification of "new pollutants.. One example of the former type of program is the U.S. EPA Mussel Watch program (National Academy of Sciences, 1980; Farrington et al., 1983), which utilizes the sentinel organism approach. Mussels on the mid-Atlantic, northeast, and west coasts, and oysters on the southern and Gulf coasts are analyzed for specific petroleum hydrocarbons and other pollutants, the rationale being that mussels reflect the water quality over an integrated time scale. Emphasis in the hydrocarbon program is on analysis of specific aromatic compounds (currently up to 4 rings) and alkylated aromatics to determine absolute levels of these compounds, their changing levels, and sources of observed hydrocarbons (i.e., whether from pyrolytic or petroleum sources). Intercalibrations have been underway in this program (Galloway et al., 19837. NOAA's Northeast (U.S.) Monitoring Program attempts to link chemical to biological parameters over time. The focus is on the analysis of sediments as a major sink for pollutants, and a selected set of organ- isms for individual PAH {and polychlorinated biphenyls (PCB) and metals) compounds. This program attempts to utilize several preexisting data bases (BLM-Benchmark; NOAA-MESA [New York Bight]), although in the past no uniform techniques of measurement have been utilized nor inter- calibrations stressed. ICES monitoring programs, in existence since 1977, have focused on metal and organochlorine residues in sediments and several fish and invertebrate species. Petroleum hydrocarbon information is beginning to be derived from this program, mainly based on specified W /F analysis, but presumably to be complemented by high resolution tech- niques as well. Residue levels are evaluated in terms of human health concerns . The ICES ~coordinated" monitor ding programs include part of NOAA's Northeast (U.S.) program as well. This program now proposes to keep the following regions under annual surveillance: Irish Sea; German Bight, Southern Bight of the North Sea; the Estuaries of the Forth, Thames, Rhine, Scheldt, and Clyde; the Skagerrak, Kattegat, and Oslo fjords; plus certain parts of the Gulf of Saint Lawrence and New York Bight. The ICES program has three monitoring rationales: (1) the provision of a continuing assurance of the quality of marine foodstuffs with respect to human health, (2) the provision, over a wide geo- graphical area, of an indication of the health of the marine environ

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133 ment in the entire ICES North Atlantic area, and {3) to provide an analysis of trends in pollutant concentrations. Intercalibration exercises for petroleum (see Petroleum Hydrocarbon Intercalibration/ Intercomparison Programs section) are underway, although many dis- crepancies in methodology need to be resolved. Monitoring for the recovery of systems following oil spills has been conducted for many spills. Once a choice of sampling stations and measurements has been made, the same concerns face these programs as well as the "baseline-type" programs. Examples of spill monitor ing programs are: Arrow shill (Keizer et al ., 1978 ), West Falmouth shill (Teal et al., 1978), Tsesis spill (Linden et al., 1980; Boehm et al., 1981b), Amoco Cadiz spill (Atlas et al., 1981), and Iranian Crude- Norway spill (Grahl-Nielson et al., 1978) . All relied on detailed chemical measurements of sediment and/or biota to monitor based on the decrease and/or modif ication of petroleum residues . - ~ recovery CONCLUSIONS AND RECOMMENDATIONS Conclusions No single method of analysis provides a measure of total petroleum in water, sediment, or tissue because of the extreme complexity of the composition of petroleum. Unfortunately, apparent economic necessity has often forced analysts to the less expensive and less discriminating methods of analysis with attendant generation of a substantial amount of data which can only be interpreted with large uncertainty. However , improved methodology for measuring fossil fuel compounds has been rapidly developed or applied since the 1975 NRC report. The range of selectivity and sensitivity makes it essential to choose the correct methods for a particular problem and to recognize the inter- pretation limits for the data. Recommendations Quality Control and Intercomparison of Data The rapid increase in the number of analysts and the demand for larger sets of data require careful quality control and intercomparison of ~ ~ ~ ~ ~ ~ ~ ~~~~ NRC report. data, now even more than at the time of the 1975 We recommend that rigorous quality assurance protocols be integrated into the analysis of hydrocarbon and other fossil fuel compounds in environmental samples. The value of standard solutions, spiked samples, spiked extracts, and sample homogenates for quality control and intercomparison has been demonstrated in a few studies.

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134 Identification of Sources of Input Many studies of petroleum inputs or distr ibution in the mar ine environ- ment have not appl fed analytical techniques to identify sources mor e exactly. The terms "petroleums" and petroleum hydrocarbons" are often used incorrectly and too loosely when describing data resulting from less discr imitating analyses. This Is especially true in regard to inclusion of pyrogenic source hydrocarbons within the data for petroleum. Application of Analytical Methods We recommend the application of analytical methods with sufficient sensitivity and resolution to identify the various sources of input, e.g., high resolution glass capillary/gas chromatography/mass spectrometry/computer systems analysis or high performance liquid chromatography analysis coupled with mass spectrometry computer systems. Nonhydrocarbon Compounds in Petroleum Because many of the nonhydrocarbon compounds in petroleum are bio- log~cally active, we recommend a more concerted effort to measure these compounds in studies of inputs, fates, and effects _ Metabolites and Photochemical Reaction Products The concern about the biological activity of several metabol ites and photochemical reaction products as indicated in the fates and effects sections leads us to recommend research into methods for measuring these compounds in samples from laboratory and field studies. These methods would be used in studies of biogeochemical processes acting on fossil fuel compounds and in studies of biological effects. We do not advocate extensive analytical chemistry data-gathering exercises in monitoring program measurements of metabolites and reaction products until such time as research has clearly demonstrated the usefulness of such an approach. Rather, we recommend the investigation of biochemical or physiological parameters as potentially more useful for determining where biologically active compounds have been or are present. Remote Sensing Sensors of various types have been tested from aircraft and show promise for providing useful information in the measurement of the areal extent and thickness of slicks. We recommend further testing in conjunction with sea truth measurements to evaluate this concept further.