OCS Study MMS 2005-041

Final Report

Trace Metals and Hydrocarbons in Sediments of the Beaufort 

Lagoon, Northeast Arctic Alaska, Exposed to Long-term 

Natural Oil Seepage, Recent Anthropogenic Activities and 

Pristine Conditions 

Principal Investigator : A. Sathy Naidu 

Institute of Marine Science 

University of Alaska 

 Fairbanks, AK 99775 

<ffsan@uaf.edu> 

Co-Principal Investigator: John J. Kelley, Institute of Marine Science 

University of Alaska 

 Fairbanks, AK 99775 

 <ffjjk@uaf.edu> 

Co-Principal Investigator: Debasmita Misra 

School of Engineering and Mines 

University of Alaska Fairbanks 

 Fairbanks, AK 99775 

<ffdm1@uaf.edu> 

 

And: M. Indira Venkatesan

Institute of Geophysics and Planetary Physics 

University of California, 

Los Angeles, CA 90095-1567 

<indira@ucla.edu>

January 2006 
Contact information 

e-mail: carter@sfos.uaf.edu 

 phone: 907.474.1811 

 fax: 907.474.1188 

 postal: Coastal Marine Institute 

 School of Fisheries and Ocean Sciences 

 P.O. Box 757220 

 University of Alaska Fairbanks 

 Fairbanks, AK 99775-7220 

ii
Table of Contents 

Table of Contents........................................................................................................................... iii 

List of Figures................................................................................................................................ iv 

List of Plates .................................................................................................................................. iv 

List of Tables...................................................................................................................................v 

Abstract............................................................................................................................................1 

Background/Relevance to Framework Issues..................................................................................3 

Hypothesis And Objectives..............................................................................................................5 

Material And Methods.....................................................................................................................5 

Results..............................................................................................................................................8 

Discussion........................................................................................................................................8 

Trace Metal Studies...................................................................................................................9 

Trace Metal Distribution Pattern:..............................................................................................9 

Acknowledgements........................................................................................................................18 

Publications and Talks Presented at International Conferences, Civic Bodies and CMI Annual 

Research Review............................................................................................................................19 

References......................................................................................................................................20 

Executive Summary.......................................................................................................................23 

iii
List of Figures 

Figure 1: Study area showing locations of sediment samples in the Beaufort Lagoon. .......... 25 

Figure 2: Map showing the study area (in filled rectangle) relative to the Arctic National 

Wildlife Refuge (ANWR) including the coastal plain unit. ...................................... 26 

Figure 3: Boxplots of standardized concentrations of 12 metals in Beaufort Lagoon 

sediments. .................................................................................................................. 27 

Figure 4: Dotplots of metal concentrations for 12 metals by station in Beaufort Lagoon....... 28 

Figure 5: Dendrogram showing Ward's linkage clustering (Euclidean distances) based on 

concentrations of 12 metals measured at each station............................................... 29 

Figure 6: Map showing relative locations of stations (coastline not shown) and group 

membership corresponding to clusters as shown in Figure 5. Stations BL03-4 

and BL03-17 (circled) did not cluster with any other stations. ................................. 30 

Figure 7: Dotplots of metal concentrations for 12 metals by cluster (see Fig. 5 for 

clusters)...................................................................................................................... 31 

Figure 8: Cumulative amount of variance explained by the first ten Principal 

Components. .............................................................................................................. 32 

Figure 9: Beaufort Lagoon stations in the space of the first two principal components. 

Groups identified by a cluster analysis (see Fig. 5) are indicated. ............................ 33 

Figure 10: Partial fit of PC 1 on silt in mud fraction after accounting for effects of latitude 

(stations BL03-4 and BL03-17 were excluded from regression). ............................. 34 

Figure 11: Partial fit of PC 1 on latitude after accounting for effects of silt in mud fraction 

(stations BL03-4 and BL03-17 were excluded from regression). ............................. 35 

Figure 12: Linear regression of PC 2 on percentage of mud in sediment (stations BL03-4 

and BL03-17 were excluded from regression). Red points show mean values of 

PC 2 corresponding to mud concentrations below and above 50%........................... 36

List of Plates 

Plate 1: Dr. Naidu pointing at the oil seep discovered south of Nuvagapak Point, Beaufort 

Lagoon............................................................................................2 

Plate 2: Dr. Kowalik in front of the ice-infested coast bluff with peat deposit eroding..........2 

iv
List of Tables 

Table 1: Sample locations, grain sizes, organic carbon (OC), nitrogen (N), OC/N, and 

stable isotopes of OC (δ13C ‰) and N (δ15N) of Beaufort Lagoon sediments.......... 37 

Table 2: Concentrations of metals in Beaufort Lagoon sediments. All are μg g–1, except 

Hg (ng g–1) and Fe (%). ............................................................................................. 38 

Table 3: Results of the QA/QC analysis concerning calibration verification.......................... 39 

Table 4: Results of the QA/QC analysis concerning calibration blanks.................................. 41 

Table 5: Results of the QA/QC analysis concerning spikes. ................................................... 42 

Table 6: Results of the QA/QC analysis concerning replicates (precision determination)...... 43 

Table 7: Results of the QA/QC analysis concerning analytical accuracy using certified 

reference materials, NIST 2709 and IAEA 405......................................................... 44 

Table 8: Correlation coefficients for chemical and physical parameters of muds from 

Beaufort Lagoon (N = 19; significant correlations [p < 0.05] are shown in bold 

and insignificant correlations are in gray). ................................................................ 45 

Table 9: Time-interval changes in the mean concentrations (μg g–1 dry wt) of trace metals 

in sediments of Beaufort Lagoon.a............................................................................. 46 

Table 10: Distribution (ng g–1 dry wt) of n-alkanes in gross sediments of Beaufort 

Lagoon. All sample numbers have the prefix BL03.................................................. 47 

Table 11: Distribution (ng g–1 dry wt) of PAHs in gross sediments of Beaufort Lagoon. 

All lagoon sample numbers have the prefix BL03. ................................................... 49 

Table 12: Distribution (ng g–1 dry wt) of triterpenoids in gross sediments of Beaufort 

Lagoon. All sample numbers have the prefix BL03. O. is the oil spill sample......... 53 

Table 13: Distribution (ng g–1 dry wt) of steroids in gross sediments of Beaufort Lagoon. 

All sample numbers have the prefix BL03. OS is the oil spill sample...................... 54 

Table 14: Component loadings for the first two PCs............................................................... 55 

Table 15: Correlations between PC 1 and PC 2 with latitude, longitude, silt and organic 

carbon. ....................................................................................................................... 55 

Table 16: Correlations between PC 1 and PC 2 with latitude, longitude, silt and organic 

carbon (excluding outliers BL03-4 and BL03-17). ................................................... 55 

Table 17: Analysis of Variance for the Response of PC 1....................................................... 55 

Table 18: Comparison of the mean concentrations of selected trace metals in Beaufort 

Lagoon mud with ERL and ERM guideline values, in percent incidence of 

biological effects in concentration ranges defined by two values as reported by 

Long et al. (1995). ..................................................................................................... 56 

Table 19: Comparison of the mean concentrations of selected hydrocarbons in Beaufort 

Lagoon gross sediments with ERL and ERM guideline values, and percent 

incidence of biological effects in concentration ranges defined by two values as 

reported by Long et al. (1995). .................................................................................. 57 

v
vi
ABSTRACT 

There is a concern that anthropogenic 

contaminants discharged during petroleumrelated activities can accumulate in the Beaufort 

Lagoon sediments. In response to this concern, 

concentrations of 12 metals were analyzed 

[copper (Cu), chromium (Cr), cadmium (Cd), 

nickel (Ni), vanadium (V), lead (Pb), tin (Sn), 

zinc (Zn), arsenic (As), barium (Ba), iron (Fe), 

and manganese (Mn)] in the mud fraction and 

total mercury (THg) and hydrocarbons 

[saturated compounds such as normal and 

isoprenoid alkanes, triterpanes, steranes and 

polycyclic aromatic hydrocarbons (PAHs)] 

determined in gross sediments collected at 22 

locations at the lagoon and in one natural oil 

seep. 

The concentrations of the metals and 

hydrocarbons are generally lower than those 

reported for polluted marine sediments. 

Comparison of time-interval metal data on sandy 

mud (>75% mud) and mud collected in 1977 

and 2003, respectively, shows a significant 

decrease in vanadium but an increase in 

manganese and copper from 1977 to 2003. 

Presumably, the differences are ascribed to 

disparities in the granulometry of the two 

sediment sets. Correlation coefficient analysis 

suggests that most metals are co-precipitated 

with iron oxy-hydroxide or occur as metalorganic complexes. There was a net increasing 

southeast to northwest trend in the metal 

concentrations, which did not relate to a possible 

gradient from point source such as the natural oil 

seep or the Distant Early Warning (DEW, now 

defunct) line station. 

The hydrocarbon components in the 

sediments are essentially of terrestrial and 

biogenic sources with undetectable petroleum 

inputs, which is supported by the Organic 

Carbon to Nitrogen ratio (OC/N), isotope ratios 

of organic carbon (δ13C) and nitrogen (δ15N) of 

organic matter. There is no evidence of the

contribution of petroleum hydrocarbons to the 

lagoon sediments from the onshore oil seeps. 

The overall composition of the hydrocarbon 

profiles is very similar to those found in our 

previous studies in the sediments from Elson 

Lagoon and near-shore regions of the Colville 

Delta–Prudhoe Bay–Canning Delta. We saw no 

impression of the natural oil seep and 

anthropogenic activities on the sediment trace 

metals and the hydrocarbon profile. The metal 

and hydrocarbon data will serve as a baseline, 

which will be critical for ecological risk 

management of the North Slope in the context of 

contaminant inputs, and in the better 

understanding of the inorganic and organic 

geochemistry of Arctic sediments.

1
Plate 1: Dr. Naidu pointing at the oil seep discovered south of Nuvagapak 

Point, Beaufort Lagoon. 

Plate 2: Dr. Kowalik in front of the ice-infested coast bluff with peat 

deposit eroding.

2
BACKGROUND/RELEVANCE TO FRAMEWORK ISSUES 

The North Slope of Arctic Alaska, 

consisting of the Coastal and Foothill Provinces 

north of the Brooks Range, and the contiguous 

nearshore zone are oil- and gas-bearing regions, 

which have a high potential for commercial 

reserves. During the past 30 years, gas has been 

extracted from the western sector of the North 

Slope (NPRA) to supply the energy needs of 

Barrow. The Prudhoe Bay field has been the 

focus of petroleum production in the North 

Slope region. More recently, a number of 

subsidiary onshore and offshore oil prospects on 

the central North Slope adjacent to Prudhoe Bay 

have either been opened for operation (Alpine, 

Kuparuk, Milne, Northstar, Endecott) or are at 

various stages of consideration for development 

(Liberty Prospect). As part of the forthcoming 

oil and gas development, the U.S. Department of 

Interior’s Minerals Management Service (MMS) 

has proposed lease sale 186 scheduled for 2003, 

sale 195 scheduled for 2005, and sale 202 

scheduled for 2007. At this point, all the sales 

would cover the same general area, and the latter 

two would re-offer unleased blocks. Further, all 

three blocks extend beyond three miles offshore 

(within the Federal jurisdiction north of the 

barrier island), extending approximately four to 

twenty miles seaward of the OCS boundary that 

begins three miles from the coast. 

The Arctic National Wildlife Refuge 

(ANWR), particularly the 1.5 million acre 

coastal plain, which has potential petroleum 

reserves (titled the 1002 area), is one of the most 

contentious areas for oil drilling, because of the 

presence of a variety of wildlife habitats 

(Douglas et al., 2002). 

The petroleum-related developmental and 

production activities (drilling, marine and 

onshore coastal traffic, and housing) and 

associated enhanced urbanization of the native 

villages close to the 186, 195 and 202 lease sale 

areas are bound to impact the nearshore 

environment of the North Slope, as suggested by 

the consequences of similar activities elsewhere 

in the adjacent coastal region. A likely result is 

the discharge of industrial and municipal 

effluents (mud, fluids and formation cuttings 

associated with drilling, dredging operations, 

sewage and garbage disposal and traffic 

emissions) laced with toxic trace metals and 

hydrocarbons into adjacent waters and/or on ice. 

Although all of the above cited lease sales are in 

the offshore region, it is probable that any 

anthropogenic contaminants discharged will be 

entrained in the littoral (alongshore) currents and 

transported inshore into the lagoons. There is 

also the possibility of accidental spilling of 

crude into the lagoons. Plans are to transport 

offshore crude by submarine pipeline to the 

shore via the lagoons. In the lagoons the 

particle-reactive contaminants can be 

subsequently concentrated in sediments by 

adsorption, ion exchange and organic complex 

formation, and/or physical co-deposition of the 

fine-sized effluent particulates with mud in the 

relatively low-energy lagoon environment. 

That concentrations of trace metals in 

sediments of the Alaskan Arctic can occur as a 

result of the discharge of drill cuttings and mud 

is documented in field experiments conducted in 

Prudhoe Bay (Northern Technical Services, 

1981), in the Canadian Beaufort Sea shelf 

(Macdonald, 1982) and by the investigations of 

Snyder-Conn et al. (1990) following drilling 

operations at three sites around Stefansson 

Sound, north Arctic Alaska. These studies 

demonstrated that the persistence of Ba, Cr, Pb 

and Zn, and elevated levels of Al (elements 

typically associated with drilling effluents) 

occurred in sediments around the discharge sites. 

Elsewhere, for example in Campbell, Australia, 

the impact of exploratory offshore drilling on 

benthic communities has been demonstrated 

(Currie and Isaacs, 2005). More recently, Naidu 

et al. (2001, 2003a), based on 30 years of timeseries monitoring of contaminants, showed a 

significant increase in Ba and V in sediments of 

the Beaufort Sea nearshore from 1977 baseline 

values to values reported in 1997 following oil 

development activities. Thus, the lagoon 

sediments of the North Slope, if they were to be 

the ultimate sink for both organic and inorganic 

anthropogenic chemicals, could be a major 

source of contaminants for benthic animals, as 

well as organisms which have a close link with 

3
sediments and which serve as transfer pathways 

of contaminants to higher trophic levels (Long et 

al., 1995, 1998; Thompson et al., 1999; ValetteSilver, 1999; Krantzberg et al., 2000; Lee et al., 

2002; Mucha et al., 2005). The role of 

contaminated marine sediments as a source of 

toxic metals and hydrocarbons to benthos has 

been documented in many case studies (refer to 

an excellent summary in Weis et al., 2004). 

Environmental contamination is of particular 

concern in the Arctic where marine organisms 

being lipid rich, having a relatively simple and 

short food chain and low biodiversity, are 

vulnerable to bioaccumulation of toxic metals. 

In response to the continued concerns for the 

fragile environment of the north Alaskan Arctic, 

especially in the context of the pending lease 

sales scheduled by MMS in 2003–2007 (tracts 

186, 195 and 202), we have extended our 

investigations (Naidu et al., 2001; 2003a) to 

establish baselines on trace metals and 

hydrocarbons in the sediments of the Beaufort 

Lagoon (Fig. 1; a map showing the study area 

within ANWR is illustrated in Fig. 2). Other 

investigations of a similar nature in the North 

Slope nearshore are those of Sweeney (1984), 

Sweeney and Naidu (1989), Trefry et al. (2003) 

and Naidu et al. (2003b) on trace metals and 

those of Steinhauer et al. (1992) on 

hydrocarbons. We contend that the chemical 

baseline data established on nearshore sediments 

from elsewhere in the North Slope (Colville 

Delta–Prudhoe Bay–Barter Island and Elson 

Lagoon; Naidu, 1982, Naidu et al., 2001, 2003a 

and references therein) cannot be extrapolated to 

the Beaufort Lagoon and the adjacent nearshore 

region east of Barter Island. The Beaufort 

Lagoon, which is located at the remote eastern 

margin of the north Alaskan Arctic coast and far 

from intense industrial activities (Fig.2), has an 

environmental setting that sets it apart from 

lagoons located in the eastern and central North 

Slope. For example, the Beaufort Lagoon 

(unlike the latter lagoons) is backed by the lower 

slopes of mountains extending close to the water 

margin. Consequently, the rivers opening into 

the Beaufort Lagoon are of relatively higher 

competency and presumably have coarser 

sediment bedload. As the dispersal of the 

sediments is contained within a relatively closed 

basin with limited marine access, the lagoon can 

be an effective trap for the accumulation of 

sediment-borne contaminants. A unique feature 

of the Beaufort Lagoon region is the frequent 

piling up of sea ice against the seaward barrier 

beach, even in summer, with ice fragments set 

floating in the lagoon. Additionally, the Beaufort 

Lagoon consists of three contrasting 

environments: two of them, Angun Point in the 

northwest and Nuvagapak Point around a 

landing strip (Fig.1) have been subjected locally 

to long-term natural oil seeps (Plate 1) and 

recent military activities, respectively. The latter 

activities were related to a defunct Distant Early 

Warning (DEW) line station, and an airstrip, 

which is still active (Fig.1). The activities 

involved land vehicular, marine boat and aircraft 

operations. Presumably, these and related 

operations exposed the lagoon region adjacent to 

the station with refined petroleum products and 

metal contaminants, which are possibly 

lingering in sediments. The rest of the lagoon 

presumably has remained pristine. It is 

anticipated that the chemistries of the sediments 

from these diverse environments will be 

significantly different and will be in contrast to 

sediments that are known to be exposed to more 

recent and fresh petroleum input. For example, 

the sediments exposed to hydrocarbons from 

natural oil seeps will likely consist of weathered 

crude oil enriched with tar and other heavy 

hydrocarbons, those from Nuvagapak Point of 

refined oil products, and those from the pristine 

lagoon of hydrocarbons derived from natural 

biogenous (terrigenous and marine) sources with 

little or no petroleum input. In the case of 

sediments that are exposed to recent petroleum 

contamination, there will invariably be a 

predominance of unweathered crude, relatively 

enriched with lighter hydrocarbons. Thus, a 

difference in composition and concentration of 

trace metals in sediments, reflecting influence by 

the different sources, can be anticipated. 

This report presents the highlights of a twoyear study (2003–2005), which has as its major 

objective the measurement of the concentrations 

of a suite of 12 trace metals [copper (Cu), 

chromium (Cr), cadmium (Cd), nickel (Ni), 

vanadium (V), lead (Pb), tin (Sn), zinc (Zn), 

4
arsenic (As), barium (Ba), iron (Fe), and 

manganese (Mn)] in the mud fraction (<63 μm 

size), and total mercury (THg), sediment grain 

size, organic carbon (OC) and hydrocarbons 

(normal and isoprenoid alkanes, triterpenoids 

and steranes and polycyclic aromatic 

hydrocarbons) in the gross sediments of the 

Beaufort Lagoon (Figs.1 and 2). The choice of 

the above metals and hydrocarbons is based on 

the fact that these chemicals are often present in 

drilling effluents, crude and petroleum 

development and production activities 

(Macdonald, 1982; Snyder-Conn et al., 1990; 

Neff, 2002). The purpose of this study was to 

close a gap in baselines for sediment metals and 

hydrocarbons for a remote region of the North 

Slope coast.

HYPOTHESIS AND OBJECTIVES 

We hypothesize that the compositions and 

concentrations of trace metals and hydrocarbons 

in the sediments of Beaufort Lagoon vary 

between the sectors that have been exposed to 

long-term (prehistoric) natural oil seep (enriched 

in weathered crude), recent military activities of 

a former DEW line station (with the input of 

anthropogenic metals and refined petroleum 

products), and the pristine environment (no 

inputs from oil seep, crude or refined petroleum 

or anthropogenic metal contaminants). 

The primary objective of this study is to 

distinguish the concentrations of 12 metals (V, 

Cr, Cu, Ni, Zn, As, Cd, Pb, Sn, Ba, Fe and Mn) 

in the mud fraction (<63 μm size), and THg and 

hydrocarbons (polycyclic aromatics and 

saturated hydrocarbons such as normal and 

isoprenoid alkanes, triterpenoids and steranes) in 

gross sediments between regions of the Beaufort 

Lagoon that are presumed to be exposed to longterm natural oil seep, anthropogenic input of 

refined petroleum products and pristine 

conditions. The objective is also to establish 

current baselines on the above trace metals and 

hydrocarbons in sediments of the Beaufort 

Lagoon for the purpose of monitoring 

contaminants.

MATERIAL AND METHODS

Samples 

In August 2003, sediment samples from the 

Beaufort Lagoon were collected at 22 selected 

stations (Fig.1; Table 1) spread over three 

sectors. The samples were collected from a 

Boston Whaler, using a Van Veen grab sampler. 

A suite of four sediment samples (BLO3-12, 

BLO3-13, BLO3-14 and BLO3-15) was 

collected east of Angun Point adjacent to a 

known onshore natural oil seep site (Lat. 

69.918° N and Long. 142.395° W, personal 

communication, Jim Clough, July 31, 2003; 

refer also to USGS, 1983), and another suite 

(BLO3-20 and BLO3-4B) off an oil seep site 

(OS) discovered by us at the bank of a small 

stream located south of Nuvagapak Point (Fig. 1, 

Plate 1). We had intended to get closer to the 

shoreline at Angun Point to collect samples from 

that area, but it was not possible to navigate to 

the Point because of the presence of extensive 

shoals in the region. A third suite of samples 

(BLO3-4, BLO3-4B, BLO3-18, BLO-19 and 

BLO3-20) was collected around Nuvagapak 

Point, a region that was impacted by military 

activities connected with a DEW line station 

(now defunct) and an active aircraft landing 

strip. A fourth suite of samples (BLO3-1, BLO3-

3, BLO3-5B, BLO3-6B, BLO3-9, BLO3-9B, 

BLO3-10, BLO3-11A, BLO3-16 and BLO3-17) 

was obtained from east of the lagoon and up 

current of Nuvagapak Point, a lagoon sector that 

is presumed pristine. Table 1 shows the 

coordinates for the sample locations, fixed by a 

GPS. 

The film of surficial sediment in contact 

with the metal sampler was discarded to 

minimize metal contamination. The remaining 

surface oxidized 2 to 4 cm portion of each of the 

5
grab samples was taken and split, using a Teflon 

spatula, into three sets of sub samples. Each of 

the splits was transferred into three separate ICAM glass jars, two of which were prerinsed 

with acid- and deionized distilled water (for 

trace metal, grain size and organic carbon 

analyses) and the third jar pre-baked and the cap 

lined with aluminum foil (for hydrocarbon 

analysis). One set was sent to Dr. M. I. 

Venkatesan, subcontractor at the University of 

California, Los Angeles for hydrocarbon 

analysis. A second set was sent to the 

subcontractor Frontier Geosciences, Seattle for 

trace metal analysis. The third set was retained 

by the PIs for analyses of the grain size, organic 

carbon and nitrogen and their stable isotopes at 

the University of Alaska Fairbanks. All these 

sediment samples were stored frozen until 

analyses. 

Laboratory Analysis 

The methods for the analyses of trace metals 

and hydrocarbons on sediments were essentially 

the same as those adopted in previously funded 

CMI/MMS studies elsewhere along the North 

Slope nearshore (Crecelius et al., 1991; 

Steinhauer and Boehm, 1992; Naidu et al., 2001, 

2003a). Therefore, we believe that the chemical 

data obtained in this study will be valid for 

comparison with the previous database 

established for the North Slope region. 

A brief description of the methods follows. 

Twelve metals (V, Cu, Cr, Ni, Zn, As, Cd, Pb, 

Sn, Ba, Fe and Mn) were analyzed in the mud 

fraction (<63μm size) of the sediment samples 

and THg in gross sediment. The rationale for 

choosing the mud fraction for the above 12 

metals and THg on the gross sediments has been 

discussed in our two previous CMI/MMSfunded studies on North Slope lagoon sediments 

(Naidu et al., 2001, 2003a). A 5-gram split of 

each sediment sample was suspended in 

deionized distilled water and the resulting slurry 

was sieved through a 230-mesh nylon screen to 

obtain the mud fraction. The mud was freezedried and pulverized using an agate mortar and 

pestle. A 0.5 gram aliquot of the dry powder was 

taken into a 140-ml Teflon bomb and digested in 

25 ml of a high-purity concentrated acid mixture 

consisting of 7ml-HF +15ml-HNO3 + 3ml-HCl 

in an oven at 130°C for 12 hours. After cooling 

to room temperature, the digest was diluted to 

100 ml with water processed by a Milli-Q 

Ultrapur Water Purification System, and the 

diluted sample returned to its original bomb. The 

resulting solution was dried and then again 

dissolved in 10% HNO3 and made up to 29 ml 

by adding deionized distilled water. From the 

final solution the 12 metals listed above were 

analyzed using either a direct injection Zeeman 

graphite furnace atomic absorption spectrometer 

(GF-AAS), a Perkin-Elmer Elan 6100 

quadrupole inductively coupled plasma mass 

spectrometer (ICP/MS) or a PSA Excalibur 

automated hydride generation atomic 

fluorescence spectrometer (for As, EPA method 

1632). Total Hg (THg) was analyzed on a 0.01–

1.0 ml aliquot of the solution retained in the 

bomb, following SnCl2 reduction and dual gold 

amalgamation pre-concentration, and using coldvapor atomic absorption spectrometry (CVAAS) 

as outlined in Bloom (1992, 1999). 

The QA/QC (quality assurance/quality 

control) protocol prescribed by the U. S. 

Environmental Protection Agency (EPA) and 

National Oceanic and Atmospheric 

Administration (NOAA) for metal analysis was 

followed. It consisted of determining analytical 

precision through replicate runs, checking 

analytical accuracy via analyses of two Certified 

Reference Materials (CRM), namely NIST 2709 

and IAEA 405, analyzing spiked sample and 

reagent blanks, and using ultrapure reagents for 

all analysis. As in our previous CMI-funded 

investigations, the trace metal analysis was 

subcontracted to Frontier Geosciences Inc., 

Seattle, which in 1997 participated successfully 

in the NOAA/NIST (National Institute of 

Standards and Testing) round robin 

interlaboratory exercise NOAA/11 for 

certification of QA/QC. The National Research 

Council of Canada (NRCC) conducted this 

exercise. The rating for the Frontier Geosciences 

was good to excellent. The results of the QA/QC 

relating to trace metals on this study are 

presented and discussed elsewhere in the report. 

The hydrocarbon analysis for n-alkanes, 

PAHs, triterpenoids and steroids was done on 

gross sediments and according to wellestablished methods (Venkatesan et al., 1980, 

6
1982, 1987; Venkatesan, 1994). After thawing 

the frozen sample the wet sediment was spiked 

with the following surrogates: deuterated nalkanes (for n-alkanes) and hexamethylbenzene, 

dodecylbenzene and deuterated terphenyl (for 

PAHs). After solvent extraction and separation 

into individual compounds by GC the alkanes 

were quantified using a flame ionization 

detector. Tricyclic, di- and pentacyclic 

triterpenoids and PAHs were measured by 

GC/mass spectrometry. As in our last two 

CMI/MMS-funded investigations (Naidu et al., 

2001, 2003a) 24 PAHs were analyzed, as well as 

six additional PAHs, which are routinely 

analyzed by NOAA/NS&T (NOAA/National 

Status and Trends Program) for QA. Dr. M. I. 

Venkatesan, UCLA, to whom the hydrocarbon 

analysis was subcontracted, successfully 

participated first in 1992 and then in 1999 in 

interlaboratory round robin exercises conducted 

by NOAA-NS&T/NIST. The QA/QC results on 

hydrocarbons pertaining to this study are 

enumerated elsewhere in this report. 

At the Institute of Marine Science, 

University of Alaska Fairbanks (IMS/UAF) 

laboratory, the sediment grain size distributions 

were analyzed by the sieve-pipette method 

(Folk, 1968). The purpose of this analysis was to 

gain understanding of the influence of 

granulometry on the concentrations of trace 

metals and hydrocarbons. The contents of 

organic carbon (OC) and total nitrogen (N) and 

their stable isotopes (δ13C and δ15N) were 

determined at UAF, on carbonate-free mud, 

following the methods outlined in Naidu et al. 

(2000) and using a Thermo Finnigan Model 

Delta Plus XP isotope ratio mass spectrometer 

(IRMS). The values of δ13C (o

/oo) are referenced 

to the V-PDB standard and those of δ15N (o

/oo) to 

air standard. The standard error of the isotope 

analysis is ± 0.2%. 

Statistical Analysis 

Statistical Analysis consisted of the 

determination of the correlation coefficients 

between trace metals, OC, N, and the silt and 

clay percents in the mud fraction, to deduce the 

geochemical partitioning of the metals in the 

mud analyzed. The comparison between two 

time intervals was obtained for the 

concentrations of selected trace metals in sandy 

muds (>75% silt and clay, after Naidu, 1981) 

collected in 1977, and mud of this study, using 

the student ‘t’ test. Cluster analysis (Euclidean 

distances, Ward’s linkage) was undertaken to 

identify grouping, if any, of stations based on 

the trace metal compositions surrounding the 

above two point sources and the pristine lagoon. 

This was followed by a principal component 

analysis of the trace metal data to correlate 

station group separation by cluster analysis with 

sediment variables. Surface trend analysis was 

conducted using trace metal data, granulometry 

and OC content to elucidate if there are any 

geographical gradient(s) in the individual 

sediment parameters and the metals from 

presumptive point sources; for example, the oil 

seeps and the abandoned DEW line station 

around Angun and Nuvagapak Points, 

respectively.

 

7
RESULTS 

The percents of solids, gravel, sand, silt, 

clay and mud in gross sediments and organic 

carbon (OC) and nitrogen (N), OC/N ratios 

(weight to weight basis of OC and N) and stable 

isotopes of OC and N (δ13C and δ15N) in the 

mud fraction of the individual samples are 

included in Table 1. In Table 2 are shown the 

concentrations (on a dry weight basis) of 12 

metals (V, Cr, Mn, Ni, Cu, Zn, As, Cd, Sn, Ba, 

Pb and Fe) in the mud fraction and of total Hg in 

the gross sediments. Table 2 also provides the 

arithmetic and geometric means of the 

concentrations of the metals analyzed on the 21 

samples and also the standard deviations and 

coefficient of variations (CV) of the analysis 

relative to each of the metals in the 21 samples 

analyzed. 

The results of the QA/QC procedure for the 

trace metal analyses in reference to calibration 

verification, calibration blanks, spikes, replicate 

analyses (for precision determination), and 

assessment of the analytical accuracy based on 

Certified Reference Materials NIST 2709 and 

IAEA 405 are presented in Tables 3, 4, 5, 6, and 

7, respectively. The correlation coefficients (r 

values) determined between the concentrations 

of silt, clay, OC, N and the 12 metals in the mud 

fraction are shown in Table 8. These correlations 

were determined by assuming the total 

percentage of silt and clay in the mud fraction to 

be 100%, and by prorating (recalculating) the 

silt and clay percents based on the relative 

percents of silt and clay in the gross samples. In 

Table 9 is shown the time-interval comparison 

for Beaufort Lagoon in the concentrations of 

selected trace metals on suites of muddy 

sediments collected in 1977 (Naidu, 1981) and 

mud sampled in 2003 (this study, Table 2). The 

concentrations of the n-alkanes, polyaromatic 

hydrocarbons, triterpanes and steranes in 

sediments are shown in Tables 10, 11, 12, and 

13.

DISCUSSION 

Sediment Grain Size, Organic Carbon (OC) 

and Nitrogen (N)) and Their Isotope 

Compositions 

The Beaufort Lagoon has a mosaic of 

sediment types, consisting of sandy muds to 

muddy sands, with occasional gravel (Table 1). 

Sediments from stations BL03-4B, BL03-19 and 

BL03-20, have significant or predominant 

amounts of gravel (Table 1). The mud fractions 

of sediments, which were taken for trace metal, 

OC, N and isotope analysis, generally contain 

relatively higher contents of silt than clay 

particles. In the gross sediments, which were 

taken for Hg analysis, there are wide differences 

in the contents of sand relative to mud. We 

discuss later the possible control of 

granulometry on the concentrations of 12 metals 

in the mud fraction and Hg in the gross 

sediments. 

Concentrations of organic carbon (OC) and 

total nitrogen (N) in the mud fraction of the 

Beaufort Lagoon sediments in this study (Table 

1) are generally higher by a factor of 1.7 

compared to the gross sediments from the 

Simpson Lagoon–Prudhoe Bay region and by a 

factor of 2.9 compared to gross sediments from 

the Beaufort Lagoon (Naidu, 1985). The higher 

content of OC in mud than in gross sediments is 

not surprising, because OC (tied with organic 

and clay mineral grains) is invariably codeposited with hydraulically similar finer silt 

and clay (mud) particles and also that clay 

minerals concentrated in mud have the greater 

ability to adsorb organics. Coarser particles such 

as sand in gross sediments are generally not 

associated with organic particles of similar size 

and, therefore, their presence in gross sediments 

tend to dilute the OC contents. 

8
The OC/N ratios, and compositions of stable 

isotopes of carbon (δ13C) and nitrogen (δ15N) in 

the Beaufort Lagoon sediments (Table 1) 

indicate that all the samples consist 

predominantly of OC/organic matter derived 

from terrestrial C3 plant sources, with minor 

input, if any, from marine or macrophyte 

sources. This interpretation is based on the 

conclusions of very exhaustive investigations 

relating to the isotopic and OC/N signatures of 

the end-member sources of OC/organic matter 

(terrestrial, marine phytoplankton, sea ice algae 

and marine macrophytes) in the coastal region of 

the Alaskan and Canadian Beaufort Sea (Naidu 

et al., 2000; Macdonald et al., 2004). Results of 

our studies on the sources of OC/organic matter 

in the Beaufort Lagoon sediments are consistent 

with those reported for the above areas and, as 

discussed later, with the conclusions on the 

sources of organics in the lagoon sediments 

based on the hydrocarbon composition. It is 

suggested that the high input of terrestrial 

OC/organic matter into the Beaufort Lagoon, as 

well as lagoons of the contiguous coastal region, 

is due to the large supply of sediments derived 

from the peat-rich shoreline, which has among 

the world’s highest coastal erosion rates, 2–10 

m/y, (Naidu et al., 2000, Macdonald et al., 2004 

and references therein). 

Trace Metal Studies 

Quality Assurance/Quality Control 

(QA/QC): The results of the calibration 

verification procedure (Table 3), consisting of, 

for each metal, the known initial calibration 

verification-true value (ICV-TV) and the ICVObserved value (ICV-OBS) showed that the 

percentage ICV recovery (ICV-Rec) for all 

metals except Fe was at acceptable levels (close 

to 100%). Likewise the blank analysis (Table 4), 

based on initial calibration blank (ICB) and the 

continuation calibration blank (CCB) on several 

runs, indicate very low contamination from the 

chemicals used throughout the analysis. Further, 

with reference to the use of spikes (Table 5) run 

in duplicates, and based on the values of the 

mean concentration of an individual metal via 

replicate analyses of a sample (Mean), Spike 

true value (Spike-TV) and observed spike value, 

we show that the spike percent recovery is close 

to 100% for all metals except Fe and Ba. The 

reason for the consistent poor showings for Fe 

and Ba is unknown, but perhaps reflects the 

inherent limitation of the use of the ICP/MS 

technique. The analytical precision (Table 6), as 

suggested by the relative percent difference 

(RPD) on duplicate analytical runs of two 

sediment samples, would seem to be excellent 

for all metals except Hg, in which case it is very 

good and at acceptable levels (< 25%). 

Likewise, the analytical accuracy (Table 7), 

determined via certified values (Cert. value), 

analyzed or Observed values (Obs.Value) of two 

Certified Reference Materials (NIST 2709 and 

IAEA 405) are again at accepted levels for all 

metals with reference to both the standards, 

except for Cr and Cd for CRM NIST 2709 and 

Fe and Sn for CRM. The above discussion 

indicates that the QA/QC for the trace metal 

analysis is generally very good to excellent and 

our data are of high quality. 

Trace Metal Distribution Pattern: In the 

following we discuss the results of the statistical 

analysis on the trace metal concentrations and 

their distributions in the mud fraction. The high 

coefficient of variations (%CV) about the mean 

for all the 13 metals (Table 2) obviously indicate 

that there are wide inter-sample variations in the 

concentrations of all the metals, with relatively 

low variability (<15% CV) for V, Cr and Fe. 

The reason for the high inter-sample variability 

in the THg contents may be ascribed to the 

differences in the sand content in the gross 

sediments, and for the rest of the metals in the 

silt and clay contents within the mud fraction. 

The other possible reason could be the 

differences in the contents of organic carbon (a 

measure of organic matter) between sediments. 

Yet another reason could be the differences in 

the Mn and Fe contents between the sediments 

analyzed. It is to be expected that the greater the 

amount of clay size particles, Mn and Fe 

contents, and/or larger content of organic carbon 

(and by implication organic matter) in the mud 

fraction or gross sediments, the relatively greater 

the concentrations of metals. This concentration 

could result from several likely processes, such 

as adsorption of metals on clays, formation of 

organic-metal complexes by ligand bonding, 

and/or co-precipitation of metals with Fe and 

Mn oxy-hydroxides. That such a granulometric 

9
control on metal content is affected in the case 

of the Beaufort Lagoon mud is demonstrated by 

the significant (p< .05) positive correlations 

between all trace metals, except Cr and Ba, and 

the clay content. The positive significant 

correlations observed between all the trace 

metals and Fe, suggests that Fe as oxyhydroxide has an important role in scavenging 

and accumulating the metals in the mud of 

Beaufort Lagoon. In this context, it is to be 

noted that all the 2–5 cm surficial sediments 

(portions analyzed for trace metals) showed, at 

the time of collection, a brownish ochre 

coloration distinct from the underlying gray 

layers, an indication that Fe in the mud analyzed 

is most likely present in an oxidized state. 

Additional detailed investigations on metal 

partitioning on sediments from Simpson Lagoon 

and Beaufort Lagoon (located east of the 

Colville Delta), based on sequential extraction 

techniques, further substantiate the role of Fe 

oxy-hydroxides in sequestering metals in the 

north Alaskan Arctic sediments (Sweeney, 1984; 

Sweeney and Naidu, 1989). Likewise, organic 

carbon and Mn in the mud (Table 8) to some 

extent bond selected few metals (Zn, Cd, As and 

Sn by OC, and Ni, Sn and Pb by Mn) by 

forming organic-metal or Mn oxide/hydroxidemetal complexation. This interpretation is 

consistent with our earlier conclusions on the 

partitioning of trace metals on lagoon sediments 

from a wide region off the North Slope coast, 

namely from the Colville Delta–Prudhoe Bay–

Canning Delta area (Naidu et al., 2001 and 

references therein) and from an earlier study in 

the Beaufort Lagoon (Naidu et al., 1981; 2003b). 

Further statistical treatment of the 

distributions of the trace metal concentrations in 

the Beaufort Lagoon mud are enumerated in the 

following: 

Univariate distributions and tests for normality 

Histograms, box-and-whisker plots and 

normal probability plots suggested that most 

metal concentrations were near-normally 

distributed, but there are a number of outliers for 

several of the metals (Figs.3 and 4). These are of 

concern in statistical modeling or hypothesis 

testing when normality is assumed. Outliers will 

have a strong influence on Pearson’s 

correlations, cluster analyses and ordinations. 

Observed outliers include: 

Cd: 2 large values at stations BL03-19, and 

BL03-20 

Cr: One low value at station BL03-4 

Mn: One relatively large value at station BL03-4 

and one large value at station BL03-17 

Ni: Low value at station BL03-4, high value at 

station BL03-17 (and BL03-20?) 

Pb: Large value at station BL03-17 

Sn: Large values at stations BL03-17, BL03-19, 

and BL03-20 

V: Low value at station BL03-4. 

Based on outliers alone, several stations 

clearly stand out as unusual (Fig. 4). These are 

BL03-4, which has low concentrations of Cr, 

Cu, Fe, Ni, Pb, V, and Zn, and BL03-17, which 

is characterized by high concentrations of Cu, 

Mn, Ni, Pb, and Sn. Stations BL03-19 and/or 

BL03-20 have similarly high concentrations of 

some, but not all, of these metals (e.g. Sn, Ni). 

These two stations are easily identified as 

outliers in the multivariate analysis (cluster 

analysis, ordination, as follows). 

Cluster analysis based on metal concentrations 

A cluster analysis based on Euclidean 

distances clearly indicated the different metal 

concentrations at stations BL03-4 and BL03-17, 

which did not cluster with any of the other 

stations (Fig.5). These two stations had a very 

different sediment composition from most other 

stations with a very low percentage of silt in the 

mud fraction (< 3%). The remaining stations 

clustered into three groups. Only one of these 

groups (Group C, consisting of stations BL03-

4B, BL03-19, and BL03-20) formed a 

geographically coherent cluster (Fig.6). Stations 

in group C were characterized by a relatively 

low percentage of silt in the mud fraction and a 

high percentage of organic matter. These 

stations contained relatively high concentrations 

of a number of metals such as Mn, Ni, Pb, Sn 

and Cd. Cluster A included the four westernmost 

stations near Angun Point, as well as a number 

of stations in the southeastern part of the lagoon. 

Cluster B consisted of the remaining stations in 

the southeastern part of the lagoon and also 

10
included station 3, which was located 

immediately adjacent to the three cluster C 

stations. Cluster A and B were distinguished by 

differences in sediment composition with a 

higher percentage of clay in the mud fraction. 

Stations in cluster B had generally higher 

concentrations of all metals, although the 

differences in means were small for Mn, Ni, Cd 

and Cr. Figure 7 summarizes the clustering of 

stations based on metal concentrations. 

Principal components analysis based on metal 

concentrations 

Results from Principal Components 

Analysis (PCA) suggest that much of the 

variability in the metal concentrations (78%) can 

be accounted for by only two Principal 

Components (Fig. 8). The station clusters, 

identified in the cluster analysis, map well onto 

the PC ordination (Fig. 9) with a clear separation 

between clusters. Stations BL03-4 and BL03-17 

are again identified as clear outliers in the biplot 

(Fig. 9). 

The loadings for the first two PCs (Table 14) 

suggest that the PC 1 reflects the average 

concentration of all metals, with high 

concentrations corresponding to high values of 

PC 1. That is, metal concentrations tend to 

increase along the x-axis in Figure 9. The PC 2 

contrasts Mn, Cd, and Sn with Ba. Large values 

of the second PC (above zero line in Fig. 9) 

correspond to high concentrations of Ba, while 

small values of PC 2 correspond to high 

concentrations of Mn, Cd, and Sn. 

Correlations between PC 1/PC 2 and latitude / 

longitude / sediment composition

Table 15 presents correlations between PC 1 

and PC 2 with latitude, longitude, silt (%) and 

OC (%). PC 1 is negatively correlated with 

latitude, implying that most of the metals 

(positive loadings on PC 1) decrease with 

latitude from southeast to northwest. PC 1 is 

also positively correlated with organic carbon 

content, reflecting a tendency for metal content 

to be higher at stations with high organic carbon 

content. This is also evident in the generally 

positive correlation between metal 

concentrations and organic carbon. 

PC 2 is strongly correlated with the 

percentage of silt in the mud fraction, implying 

that Mn, Cd, Sn and Pb (metals that are 

negatively correlated with PC 2, see above) 

decrease with silt content, while Zn and Ba 

increase with mud content (this is also obvious 

in direct correlations between metal 

concentrations). 

The above correlations are strongly 

influenced by the outlying stations (BL03-4 and 

BL03-17). Therefore, the correlations excluding 

those 2 stations were computed (Table 16). 

After exclusion of the 2 “outliers”, PC 1 was 

most strongly correlated with the proportion of 

silt in the mud fraction and the percentage of 

organic carbon. This implies a strong decrease in 

the silt fraction and an increase in the organic 

carbon along the x-axis in Fig. 9 (Group C > 

Group B > Group A). In contrast, the PC 2 is 

positively correlated with the silt fraction. Thus, 

the silt fraction increases along the y-axis in Fig. 

9 (Group B > Group A > Group C). 

Multiple regressions of PC 1 and PC 2 with 

latitude, longitude and sediment characteristics 

PC 1: The model that best explained 

variability in metal concentrations (as reflected 

in PC 1) was a regression of PC 1 on the silt 

fraction and latitude (best model chosen based 

on Akaike Information Criterion (AIC)). The 

regression (Fig. 10, Table 17) captured 72% of 

the variability in PC 1 and also captured the 

strong decrease in PC 1 with the silt fraction and 

with latitude. While the silt fraction explained 

most of the overall variability, a significant 

effect of latitude on PC 1 remained after 

accounting for the effects of silt. This effect 

reflected a southeast-northwest gradient in metal 

concentrations that primarily separates stations 

BL03-10, BL03-12, BL03-13, and BL03-14 in 

the northwestern part of the lagoon (4 points on 

the lower right in Fig. 11) from the remaining 

stations. 

The geographic gradient was confirmed by 

simple linear regressions of individual metal 

concentrations on latitude/longitude (rotated axis 

to reflect SE–NW direction), which showed 

significant increases (p < 0.05) from NW to SE 

in Cu (t = 2.72, p = 0.016), Zn (t = 2.23, p = 

0.041), and Ba (t = 2.90, p = 0.011). 

11
PC 2: The best model explaining variability 

in PC 2 was a simple linear regression on mud 

content, which explained 77% of the variability 

in PC2. After accounting for the effects of mud, 

there was no significant effect of latitude, 

longitude or other sediment variables. A 

“threshold” model that fits separate means at 

low and high mud concentrations fit slightly 

better (in terms of AIC) than the linear model 

(Fig. 12). Stations with low mud concentrations 

in the lower left of Fig. 12 were characterized by 

low values of PC 2, reflecting high 

concentrations of Mn and Sn and low 

concentrations of Ba. These included most of the 

stations in the northwestern part of the lagoon. 

In summary, a PCA based on metal 

concentrations primarily separates stations with 

relatively high metal concentrations from 

stations with relatively low concentrations along 

PC 1 (56% of overall variability). PC 2 (23% of 

overall variability) contrasts stations that tend to 

be high in Mn, Cd, and Sn and low in Ba (Group 

C and stations BL03-4 and BL03-17) with 

stations that tend to show the opposite pattern 

(e.g. Group A). These differences in metal 

concentrations reflect both geographical 

differences and differences in sediment 

characteristics. In general, there was a tendency 

for total metal concentrations (PC 1) to decrease 

with the silt fraction and with latitude from S to 

N and to increase with organic matter content. 

While much of the variability in metal 

concentrations was explained by sediment 

characteristics, a significant geographical 

gradient remained even after accounting for the 

effects of sediment composition on PC 1. This 

gradient reflects differences in metal 

concentration between the “pristine” 

southeastern lagoon (higher concentrations of 

most metals) and the northwestern part of the 

lagoon that is not explained by differences in 

sediment composition. 

The trends of metal concentrations decrease 

from southeast to northwest across the study 

area. It seems clear, therefore, that there are no 

definite distributional patterns in the 

concentrations of trace metals in the mud of 

Beaufort Lagoon, especially in the context of the 

hypothesis that we had mooted at the start of the 

project. We had predicted that there would be 

significant differences in the metal 

concentrations between the regions exposed to 

natural oil seep, anthropogenic activities such as 

those related to the defunct DEW line station 

and the pristine environment portions of the 

lagoon. The above gradient is opposite to what 

one would expect, considering the presumed 

contaminant sources. It is suggested that any of 

the 13 metals investigated that might have been 

input into the lagoon from the oil seeps and/or 

past military activities are dispersed so widely 

and are so diluted that the effect of the point 

sources of the natural and anthropogenic 

contaminants are not decipherable in the lagoon 

mud. In summary, there is no significant 

difference between mud collected from possible 

“impacted areas” and the pristine portion of the 

lagoon, suggesting that the lagoon has remained 

uncontaminated as far as the trace metals 

analyzed in this study. 

It is noted that the mean concentrations of 

all trace metals in the mud fraction of Beaufort 

Lagoon are generally close to the levels reported 

by us on mud samples from the Colville Delta–

Prudhoe Bay–Canning Delta region (Naidu et 

al., 2001). Further, the mean concentration of 

THg in the gross sediments of Beaufort Lagoon 

is significantly higher (mean: 57 ng/g) than in 

gross sediments of the above deltaic region 

(mean: 19 ng/g). This difference in Hg is 

probably due to differences in the natural input 

of Hg from the hinterland sources, a proposition 

that remains to be further investigated. 

Time-interval comparison of the mean 

concentrations of metals 

A comparison is shown in Table 9 of the 

mean concentrations of a selected six metals 

between 5 sandy mud (>75% silt + clay) and 21 

mud samples, which were collected in 1977 and 

this study (2003) respectively from Beaufort 

Lagoon. A significant (p< .05) decrease in V and 

an increase in Mn and Cu are noted from 1977 

to 2003, whereas no differences in the time 

interval mean concentrations in Cr, Ni and Zn 

are identified. The differences may be artifacts 

of the differences in the granulometry and 

organic carbon contents between the two sets of 

samples rather than metal pollution, as alluded 

to previously. It is to be noted that we have 

12
minimized the effect of granulometry by 

restricting the comparison to mean metal values 

on sandy mud samples of 1977 and mud samples 

in this study. The fact that there is no wholesale 

increase in the mean concentrations of all or 

most of the metals concerned is consistent with 

our earlier inference that the Beaufort Lagoon 

has remained generally a clean environment 

over the 26-year period (1977–2003), despite the 

fact that the lagoon had been subjected to past 

anthropogenic activities from the operation of a 

Distant Early Warning (DEW) Line station. 

Predicting toxicity in sediments with numeral 

trace metal quality guidelines 

The mean concentrations of selected trace 

metals in Beaufort Lagoon mud were used to 

determine their potential for adverse effects on 

resident marine benthic organisms, following the 

guidelines proposed by Long et al. (1995, 1998). 

Long et al., based upon empirical analysis of a 

broad database consisting of equilibriumpartitioning modeling, laboratory bioassays and 

field studies on total sediments have developed 

two sediment quality guideline (SQG) values [an 

effects range-low (ERL), and an effects rangemedium (ERM)]. The database specifically 

consisted of concentrations of selected trace 

metals and hydrocarbons and biological effects 

on numerous benthic taxa in gross sediments. 

Further, “The two values defined concentration 

ranges that were: (1) rarely, (2) occasionally or 

(3) frequently associated with adverse effects.” 

Comparison of the mean concentrations of 

heavy metals in mud from the study area with 

the above ERL and ERM and the three ranges 

for selected metals listed in Long et al., 1995 

(Table 18), indicates that the mean 

concentrations of As, Cu and Ni in Beaufort 

Lagoon mud fall into ERL category and Cd, Cr, 

Pb, Hg and Zn are below ERL. This implies that 

the concentrations of As, Cu and Ni in the mud 

of Beaufort Lagoon are above the threshold level 

where incidences of adverse effects on biota 

would occasionally occur. However, whether the 

extrapolation of the guideline suggested by Long 

et al. (1995) is relevant and applicable to our 

study in the Beaufort Lagoon is a question that 

needs to be further investigated. At the outset, 

to some it would seem that the above 

comparisons are incompatible, because our 

metal data is on the mud fraction (<63 μm size) 

of gross sediments whereas Long et al’s 

guideline is based upon trace metals 

concentrations in gross sediments which may 

not be composed entirely of mud. Any 

infiltration of coarser materials such as gravel or 

sand size particles can dilute the trace metals in 

gross sediment. It could be argued that the 

comparison is invalid because trace metals are 

almost invariably enriched in the mud fraction 

compared to gross sediments admixed with the 

coarses, because of the presence (partitioning) in 

the mud of chemically more reactive 

components (e.g., clay minerals and organics). 

The latter components have high ability to 

concentrate metals by adsorption and/or 

formation of organic-clay-metal ligands or 

complexes. So, in such gross sediments with 

little mud content the concentrations of metals 

will likely be low. Although we concede that the 

above comparison is not totally compatible we, 

nonetheless, contend that the comparison has 

some implication on predicting sediment toxicity 

in the study area. Our contention is based on the 

general premise that most benthic organisms 

selectively ingest fine particles (Lee et al., 

2000). Therefore, by implication, any high 

concentration of metal(s) bound to the fine 

particles would expose the animals to possible 

adverse effects. It is suggested that any 

conclusions based on the Long et al.’s guidelines 

must be substantiated by detailed site-specific 

cause-effect investigations in Beaufort Lagoon 

on individual resident organisms. Further, it is to 

be noted that a lack of consensus exists as to 

which aspects of the sediment trace metal 

chemistry are responsible for the adverse effect 

(Grant and Briggs, 2002). It is suggested that an 

assessment must be made of the fractions of 

various metals in the gross sediment that will be 

potentially available for bio-accumulation. 

Investigations on the amounts of metals 

partitioned in various sediment phases 

[interstitial fluids, extractable phase following 

acid or acid-reducing agent treatment, acid 

volatile sulfides (Mucha et al. 2005, and 

references therein)] will provide more 

meaningful information on the bioavailability of 

metals from sediments. The unique problems 

relating to polar marine toxicology and the 

13
future special research needs for the region has 

been discussed by Chapman and Riddle (2005). 

Hydrocarbon Studies 

Discussions on the hydrocarbon studies are 

focused on two aspects; one to elucidate the 

sources of the hydrocarbons, and the second to 

assess whether the types and concentrations of 

hydrocarbons in the Beaufort Lagoon sediments 

are in any way different than from nearshore 

sediments elsewhere in the North Slope region. 

Criteria to infer hydrocarbon sources 

We assessed the relative abundance of the 

various sources of hydrocarbons (natural oil 

seep, refined petroleum, fresh crude and natural 

terrestrial and marine biogenous origin) in each 

of the sediments analyzed by using, for example, 

the following guidelines. 

Natural crude seepage: Weathered 

petroleum; Alkane gas chromatogram with a 

hump (unresolved complex mixture of branched 

and cyclic components) (Farrington and Tripp, 

1977; Simoneit and Kaplan, 1980; Venkatesan et 

al., 1980). 

Fresh petroleum: Unweathered petroleum; 

characterized by n-alkanes distribution with no 

odd/even carbon preference throughout the 

carbon number envelope (Philip, 1985); 

alkylcyclohexanes and alkylbenzenes are found 

at significant levels, pristine and phytane are 

usually more dominant than C17 and C18 nalkanes (Zafiriou et al., 1972), triterpenoids are 

of high thermal maturity characterized by the 

presence of predominantly 17α-hopanes and 

moretanes (17βα-hopanes) (Dastillung and 

Albrecht, 1976). Alkylated PAHs are more 

dominant than the parent PAHs (Youngblood 

and Blumer, 1975). 

Biogenic hydrocarbons: Alkane gas 

chromatogram normally has baseline resolved 

peaks and does not have a bump (unresolved 

complex mixture of branched and cyclic 

components) (Venkatesan and Kaplan, 1982). 

C15, C17 indicates dominant n-alkanes from 

marine plankton, whereas dominance of C-25 to 

C-31 n-alkanes indicates terrestrial plant wax, 

with C25, 27, 29, 31 and 33 more dominant than 

the even carbon n-alkanes (resulting in a high 

odd/even ratio) and with the maximum at C29 or 

C31 n-alkane (Simoneit and Kaplan, 1980; 

Venkatesan et al., 1980). There was a presence 

of significant levels of alkanes from marine 

biota (Blumer et al., 1971). Triterpenoids are of 

low thermal maturity, characterized by the 

presence of predominantly 17β-hopanes and 

hopanes (Dastillung and Albrecht, 1976). There 

were not many alkylated PAHs. 

General characteristics of hydrocarbons as 

related to their sources 

In the following, we enumerate the major 

criteria that were used to identify the possible 

sources of hydrocarbons in Beaufort Lagoon 

sediments. 

Alkanes: The alkane gas chromatogram 

exhibits baseline separation of the components 

and is generally bimodal with the major 

maximum at n-C27 in 14 of the 20 samples 

analyzed and at n-C29 or n-C31 in the remaining 

sediments (Table 10). Normal alkanes >C25

predominate in all the sediment samples with 

odd/even carbon alkanes ratio in the range from 

3.5 to 8.1. These alkanes are derived from higher 

plants. The secondary maximum at n-C17 is 

characteristic of aquatic algae. The C20 and C21

olefins found are derived from plankton and 

bacteria. Although the total n-alkane level varies 

from 0.1 to 34μg/g similar to the Elson Lagoon 

sediments, Beaufort Lagoon sediments, in 

general, seem to exhibit relatively greater 

vascular inputs than the Elson Lagoon 

sediments. 

In contrast, the O.S. (Oil Seep) sample 

contains a 100 to 1000-fold concentration of nalkanes compared to the sediments (i.e., μg/g 

level vs. ng/g level as found in sediments, Table 

10). Very high amounts of n-C10 through n-C15

and significant levels of alkanes from n-C20 to nC32 over a pronounced unresolved hump (UCM 

= unresolved complex mixture spanning n-C21 to 

n-C34) are found in this sample. The most 

dominant alkane is n-C11. There is practically no 

single dominant n-alkane at the high molecular 

weight end where the odd/even ratio is at 1.3, 

typical of petroleum input. From the overall 

profile of the n-alkanes, it appears that the O.S. 

may be degraded petroleum. 

In addition, the L/H ratio ( ∑C12-C19/∑C20-

C33 alkanes) of the O.S. is 0.6, which is much 

14
higher than in the lagoon sediments (0.05–0.13) 

as computed from Table 10. Only one sample 

(BL03-14) has measurable pristane and phytane 

and the O.S. has neither of the two. The C20 and 

C21 planktonic olefins, which are found in all the 

sediments, are absent in the O.S. sample. 

Therefore, the n-alkanes distribution in the 

sediment samples is markedly different from 

that in the O.S. sample, implying that the lagoon 

sediment is relatively pristine with no 

measurable petroleum contribution. 

Distribution and sources of hydrocarbons in 

Beaufort Lagoon sediments 

 Polyaromatic Hydrocarbons (PAHs): The 

levels of total PAH in the Beaufort Lagoon 

sediments range from 30 to 710 ng/g (Table 11) 

and are comparable to sediments from Colville 

Delta–Prudhoe Bay–Canning Delta (2001), 

Elson Lagoon (Naidu et al., 2003a) and other 

nearshore regions of the Beaufort Sea. The PAH 

composition is dominated by the homologous 

series of phenanthrenes. The sum of parent PAH 

and their methyl homologs distribution follows 

generally in the order: phenanthrenes> 

naphthalenes>chrysenes/triphenylenes 

>fluoranthenes/pyrenes. C2- naphthalene and C1- 

phenanthrene in all the samples and C1-chrysene 

in four samples are the most dominant PAH 

homologs. The general dominance of parent and 

monomethylated PAHs over higher methylated 

homologs in the lagoon sediment samples 

suggests the absence of significant petroleum 

input in the sediments. Compared to the lower 

molecular weight PAHs, four and five-ring 

PAHs are relatively less and perylene is the most 

dominant parent PAH in all the samples except 

in BL03-17, which has the least PAH content 

and contains no perylene. The dominance of 

perylene in the sediments is consistent with its 

origin in the Alaskan peats, similar to that found 

in coastal and other lagoon sediments of north 

Arctic Alaska (Naidu et al., 2000, 2003a; 

Macdonald et al., 2004, and references therein). 

This interpretation is consistent with the 

relatively light (negative) values of carbon 

isotope ratios (δ13Co

/oo, Table 1) of all 

sediments, which point to a predominantly 

terrestrial (C3) plant source of OC/organic 

matter in Beaufort Lagoon (see also Naidu et al., 

2000), from peat from coastal erosion (Plate 2). 

The O.S. (oil seep) sample contains 208μg/g 

of total PAHs, about 1000-fold greater than the 

lagoon sediments, also consistent with the trend in 

n-alkanes content. Unlike in the lagoon sediments, 

naphthalenes are the most dominant PAHs in the 

O.S., and, similar to the dominance of low 

molecular weight C10-C15 n-alkanes over high 

molecular weight analogs. Further, the

anomalously high value of the 

naphthalenes/phenanthrenes ratio in the O.S. is 

observed (7.62) in contrast to the very low range 

in the sediments (0.03–0.91). C2-naphthalenes, C2-

phenanthrenes and C3-chrysenes/triphenylenes are 

the most dominant methyl homologs, 

characteristic of petroleum. Neither any PAH 

beyond C4-chrysenes/triphenylenes nor perylene 

are detected in the O.S. The sum of parent PAH 

and methyl homologs follow the order: 

naphthalenes>phenanthrenes~ 

chrysenes/triphenylenes>fluoranthenes/pyrenes. 

The overall molecular composition of PAHs 

in the Beaufort lagoon sediments and a 

comparison to that of the O.S. sample imply an

absence of petroleum in the Beaufort Lagoon 

sediments, which is consistent with that noted 

above from the alkanes profiles. The 

hydrocarbon composition of the sediments from 

the Beaufort Lagoon is comparable to those 

from Elson Lagoon and most of the Beaufort 

Sea sediments investigated by us in previous 

CMI/MMS studies. 

Triterpanoids: Triterpanes are mostly 

biogenic in the sediments as reflected by the 

presence of five major components, i.e., 

27(17β)-, 29ββ-, 29βα-, 30ββ- hopanes and 

diploptene (Table 12). The most dominant 

hopanoid is diploptene and 29ββ-hopane is the 

second most dominant. Thermally mature 29αβand 30αβ-hopanes are present in much 

smaller/trace amounts relative to biogenic 

hopanes. Extended hopanes with >C31 are either 

not detected or present only in trace quantities 

and only the R isomer is detected. 

Similar to n-alkanes, total triterpanes are at 

the μg/g level and are about 1000-fold greater in 

the O.S. sample than in the lagoon sediment 

samples, where they occur at the level of ng/g. 

Further, the O.S. contains a whole suite of 

thermally mature αβ-hopanes and none of the 

15
biogenic ββ- and βα-hopanes or the hopenes. 

Both S and R diastereomers of the extended 

hopanes (i.e., >C31-hopanes) are present. This 

hopane’s distribution in the O.S. is typical of 

petroleum/thermally mature sediments. 

The trace amounts of isolated, thermally 

mature (αβ and/or βα-hopanes) biomarkers 

detected in the sediments most probably derive 

from peat and/or coal. The overall fingerprint of 

the triterpanes in sediments of the Beaufort 

Lagoon does not support any contribution from 

the O.S. 

Steranes: Steranes are generally absent in 

the Beaufort Lagoon sediment samples. If 

present, they are only in small/trace amounts, 

usually about 10 times lower than triterpanes 

(Table 13). Sediment samples, BL03-12, -13 and 

-14 contain almost a whole suite of target 

steranes and at relatively higher levels than the 

other sediments. This probably implies minimal 

petroleum input. However, this observation is 

not supported by triterpane or n-alkane profiles. 

Also, considering the extremely low levels of 

steranes in these samples, the input from 

petroleum may not be warranted. The other 

samples, which contain smaller amounts of a 

few steranes, are 6B, 18 and 19. 

All of the target steranes usually associated 

with natural weathered oil are present in the O.S. 

sample and it is about 1000-fold greater than in 

the lagoon sediments. The steranes profile of 

O.S. clearly indicates petroleum characteristics. 

In summary, normal and cyclic alkanes 

distribution is characteristic of biogenic origin in 

all the sediment samples and is different from 

that of the O.S. sample, thus indicating very 

little or no petroleum input to the Beaufort 

Lagoon sediments. The overall profile of alkanes 

in the Beaufort Lagoon sediments is similar to 

those of near-shore sediments from the Beaufort 

Sea that were analyzed by us in previous 

CMI/MMS projects (Naidu et al., 2001; 2003a). 

The alkane’s distribution of O.S. sample, in 

contrast, clearly reflects that of petroleum. The 

overall profiles of the hydrocarbons indicate a 

significant derivation of them from terrestrial 

plants, which is corroborated by the OC/N and 

stable carbon isotope ratios. That the terrestrial 

organic matter pervades (50%) the organic 

matter of sediments throughout the Alaskan–

Canadian near-shore is substantiated by more 

extensive investigations on OC/N, δ13C, δ15N 

and n-alkanes of sediments of the region (Naidu 

et al., 2000; Macdonald et al., 2004). 

Predicting toxicity in sediments with PAH 

quality guidelines 

As in the case of the trace metals, we have 

examined the mean concentrations of a group of 

PAHs in the context of Long et al.’s (1995, 

1998) guidelines for identifying hydrocarbon 

pollution in terms of Effects Range-Low (ERL) 

and Effects Range-Medium (ERM) (refer to the 

related discussion above on trace metals). Our 

study indicates that the mean concentrations of 

all the PAHs in gross sediments of the Beaufort 

Lagoon are below the threshold ERL level 

where incidences of adverse effects would be 

expected on biota (Table 19). 

Conclusions 

Interpretations of the trace metal and 

hydrocarbon data provide the following 

conclusions. There are no significant disparities 

in the metal concentrations between the regions 

exposed to long-term natural oil seep, past 

anthropogenic activities related to the DEW line 

military station and the pristine environment of 

the lagoon. It is suggested that any of the 13 

metals investigated that might have been input 

into the lagoon, from the oil seeps and/or past 

military activities, are dispersed so widely and 

diluted that the affect of the point sources on the 

metal contents are not discernable. Two timeinterval comparisons of the mean concentrations 

of metals in muddy sediments taken at 26-year

intervals (1977 to 2003) show a significant 

decrease in V, an increase in Mn and Cu, and 

similar values in Cr, Ni and Zn. Data on the rest 

of the metals were unavailable for 1977. The 

differences mentioned above likely reflect the 

differences in granulometry and organic carbon 

contents between 1977 and 2003 samples. It is to 

be noted that the 1977 samples were comprised 

of sandy mud and not entirely of mud as in the 

case of the 2003 samples. The mean 

concentrations of all trace metals, except THg, 

in the mud of Beaufort Lagoon are generally at 

the same level as those reported by us from the 

Colville Delta–Prudhoe Bay–Canning Delta 

region. The significantly higher THg values in 

16
Beaufort Lagoon mud (mean: 57 ng/g) than in 

the above region (mean: 19 ng/g) is probably 

due to differences in the natural input of the 

metal from the hinterland, a proposition that 

remains to be further investigated. Correlation 

coefficient analysis between metals, OC and 

granulometry, suggests that clays and Fe 

presumably play an important role in metal 

scavenging and their deposition in Beaufort 

Lagoon, a conclusion consistent with our results 

on metal partitioning in the Beaufort Sea nearshore. Based on principal component analysis, it 

is evident that a southeast-northwest high to low 

gradient is present in the study area in the 

concentrations of the trace metals. We attribute 

this trend to likely net regional variations in 

granulometry, organic carbon contents and/or 

possible changes in the natural input of metals 

contents along the above gradient, rather than a 

reflection of a gradient resulting from decreasing 

inputs from potential point sources of 

contaminants, such as from existing natural oil 

seeps and/or from the past activities of the 

Distant Early Warning (DEW) line station 

located south of Nuvagapak Point. 

The hydrocarbon components in gross 

sediments from the Beaufort Lagoon are 

biogenic and terrestrial with little petroleum 

input. Their general composition is very similar 

to those found in the sediments from Elson 

Lagoon, Colville Delta–Prudhoe Bay–Canning 

Delta and the adjacent Canadian deltaic and 

inner shelf region and the inner shelf of the 

Beaufort Sea. The data provide no evidence to 

document the contribution of petroleum 

hydrocarbons to the Beaufort Lagoon sediments 

analyzed from the oil seeps located in the 

vicinity and anthropogenic activities. Petroleum 

contribution, if there is any to the sediments, is 

only minimal, below detection levels. The trace 

metal and hydrocarbon levels are either similar 

to or below those reported for unpolluted nearshore regions of the world. In summary, the 

Beaufort Lagoon sediments have remained 

uncontaminated as far as the analyzed trace 

metals and hydrocarbons are concerned. 

The mean concentrations of As, Cu and Ni 

in the mud of the Beaufort Lagoon are above the 

threshold level of Effects Range-Low (ERL) that 

can cause adverse effects on benthic and 

demersal organisms. This is a tentative 

conclusion which must be clarified by further 

detailed investigations on the metal partitioning 

patterns and determination of the portions of 

metals that will likely be made available for 

possible bioaccumulation.The mean 

concentrations of all the selected 14 

hydrocarbons in the gross sediments of Beaufort 

Lagoon are below the ERL, which implies that 

no adverse effects can be expected from 

hydrocarbons on benthic and demersal 

organisms. 

17
ACKNOWLEDGEMENTS 

This study was funded by the Minerals 

Management Service, U. S. Department of the 

Interior through Cooperative Agreement 1435-

01-98-CA-30909 (Task Order 74464) between 

the MMS Alaska OCS Region and the Coastal 

Marine Institute, University of Alaska 

Fairbanks. Matching funds were provided by the 

Institute of Marine Science, University of 

Alaska Fairbanks and the University of 

California, Los Angeles. Thanks are due to 

Zygmunt Kowalik for assistance in the sample 

collection, and to Franz Mueter for the 

assistance in the statistical analysis of the trace 

metal data. The continued encouragement by 

Vera Alexander, Director, CMI, and the 

excellent cooperation of Ruth Post and Kathy 

Carter of CMI, Kate Wedemeyer, Cleve Cowles 

and R. Prentki of MMS Anchorage throughout 

this study is appreciated. Grateful thanks are 

also due to Maggie Billington and Kathy Carter 

in the preparation of the report. 

18
PUBLICATIONS AND TALKS PRESENTED AT INTERNATIONAL CONFERENCES, 

CIVIC BODIES AND CMI ANNUAL RESEARCH REVIEW

Naidu, A. S., Kelley, J. J. and Goering, J. J. 

2003. Three decades of investigations on 

heavy metals in coastal sediments, North 

Arctic Alaska: a synthesis. J. Phys. IV 

France, 107:913–916. 

Kelley, J. J., Naidu, A. S. and Goering, J. J. 

2004. Trace metals in sediments of Elson 

Lagoon (Northwest Arctic Alaska) as related 

to the Prudhoe Bay industrial region. Talk 

by Dr. Kelley. Proc. 19th Intn’l. Symposium 

on Okhotsk Sea and Sea Ice, Mombetsu, 

Hokkaido, Japan. 175–179. 

Naidu, A. S., Kelley, J. J. and Misra, D. 2004. 

Heavy metal monitoring in sediments of 

theNorth Alaskan Arctic. Oral presentation

(invited) by Dr. Naidu at the Annual 

Oceania Geosciences Society’s (AOGS) 

First Annual Meeting, Singapore, July 2004. 

(Abstract Published). 

Naidu, A. S., Kelley, J. J., Misra, D. and 

Venkatesan, M. I. 2003. Trace Metals and 

Hydrocarbons in Sediments of Beaufort 

Lagoon, Northeast Arctic Alaska, Exposed 

to Long-term Natural Oil Seepage, Recent 

Anthropogenic Activities and Pristine 

Conditions. Oral presentation by Dr. Naidu 

at the CMI Annual Research Reviews, 

February 17, 2004 and March 8, 2005. 

Naidu, A. S., Kelley, J. J., Misra, D. and 

Goering, J. J. 2003. Responsible industrial 

development in the North Slope nearshore: 

sediment trace metal history. Luncheon talk 

given by Dr. Naidu at the Alaska Miner’s 

Association, Fairbanks. 

Macdonald, R. W., Naidu, A. S., Yunker, M. B. 

and Gobeil, C. 2004. The Beaufort Sea: 

distribution, sources, fluxes and burial of 

organic carbon. In: R. Stein and R. W. 

Macdonald (eds.), The Organic Carbon 

Cycle in the Arctic Ocean, Springer-Verlag, 

Berlin, 177–193. 

Misra, D., Naidu, A. S., Kelley, J. J., 

Venkatesan, M. I. and Mueter, F. 2006. 

Heavy metals and hydrocarbons in Beaufort 

Lagoon Sediments, North Arctic Alaska. In

Y. J. Xu and V. P. Singh (eds.), Coastal 

Environment and Quality, Vol. II, Chapter 3. 

ISBN 1-887201-47-5. In press. 

 Naidu, A. S., Kelley, J. J. and Goering, J. J. 

2005. Heavy metals. In: Mark Nuttall (ed.), 

Encyclopedia of the Arctic, v. 2 (G-N), 

Routledge, New York, 851–852. 

Naidu, A. S., Kelley, J. J. and Misra, D. 2005. 

Responsible petroleum-related industrial 

development in the North Slope coastal 

region, Arctic Alaska: evidence from thirty 

years of monitoring of trace metals in 

sediment. Oral presentation by Dr. Naidu at 

the XII International Conference on Heavy 

Metals, Rio de Janeiro, Brazil, June 2005. 

In: Proc. XIII International Conference on 

Heavy Metals in the Environment, Trindade, 

R. de B.E., Melamed, R., Sobral, L.G. dos 

S., and Barbosa, J.P. (Eds.), p. 637–641.

. 

19
REFERENCES 

Bloom, N.S. 1992. On the chemical form of 

mercury in edible fish and marine 

invertebrate tissue. Can. J. Aquatic Sci. 

49:1010–1017. 

Bloom, N.S., G.A. Gill, S. Cappellino, C. 

Dobbs, L. McShea, C. Driscoll, R. Mason 

and J. Rudd. 1999. Speciation and cycling 

of mercury in Lavaca Bay, Texas, 

sediments. Environ. Sci. Technol. 33(1):7–

13. doi: 10.1021/es980379d 

Blumer, M., R.R.L. Guillard and T. Chase. 

1971. Hydrocarbons of marine 

phytoplankton. Mar. Biol. 8(3):183–189. 

doi: 10.1007/BF00355214 

Brown, R.E. 1987. Emergency/Survival 

Handbook, 4th ed. American Outdoor Safety 

League. Mountaineers Books, Seattle, 

Washington, 45 p. 

Chapman, P.M., and M.J. Riddle. 2005. Polar 

marine toxicology – future research needs. 

Mar. Pollut. Bull. 50(9):905–908. 

doi:10.1016/j.marpolbul.2005.06.001 

Crecelius, E.A., J.H. Trefry, M.S. Steinhauer 

and P.D. Boehm. 1991. Trace metals in 

sediments from the inner continental shelf of 

the western Beaufort Sea. Environ. Geol. 

18(1):71–79. 

doi: 10.1007/BF01704579 

Currie, D.R., and L.R. Isaacs. 2005. Impact of 

exploratory offshore drilling on benthic 

communities in the Minerva gas field, Port 

Campbell, Australia. Mar. Environ. Res. 

59(3):217–233. 

doi:10.1016/j.marenvres.2004.05.001 

Dastillung, M., and P. Albrecht. 1976. 

Molecular test for oil pollution in surface 

sediments. Mar. Pollut. Bull. 7(1):13–15. 

doi:10.1016/0025-326X(76)90282-4 

Douglas, D.C., P.E. Reynolds and E.B. Rhode 

[eds.]. 2002. Arctic Refuge Coastal Plain 

Terrestrial Wildlife Research Summaries. 

Biological Science Report, 

USGS/BRD/BSR-2002-0001, U.S. Geol. 

Survey, Reston, Virginia, 75 p. 

Farrington, J.W., and B.W. Tripp. 1977. 

Hydrocarbons in western North Atlantic 

surface sediments. Geochim. Cosmochim. 

Acta 41(11):1627–1641. doi:10.1016/0016-

7037(77)90173-9 

Folk, R. 1968. Petrology of Sedimentary 

Rocks. Hemphill Publishing Co., Austin, 

Texas, 70 p. 

Grant, A., and A.D. Briggs 2002. Toxicity of 

sediments from around a North Sea oil 

platform: Are metals or hydrocarbons 

responsible for ecological impacts? Mar. 

Environ. Res. 53(1):95–116. 

doi:10.1016/S0141-1136(01)00114-3 

Krantzberg, G., J.H. Hartig and M.A. Zarull. 

2000. Sediment management: Deciding 

when to intervene. Environ. Sci. Technol. 

34(1):22A–27A. 

Lee, B.-G., S.B. Griscom, J.-S. Lee, H.J. Choi, 

C.-H. Koh, S.N. Luoma and N.S. Fisher. 

2000. Influences of dietary uptake and 

reactive sulfides on metal bioavailability 

from aquatic sediments. Science 

287(5451):282–284. doi: 

10.1126/science.287.5451.282 

Lee, H.J., and P.L. Wiberg. 2002. Character, 

fate, and biological effects of contaminated, 

effluent-affected sediment on the Palos 

Verdes margin, southern California: An 

overview. Cont. Shelf Res. 22(6–7):835–

840. doi:10.1016/S0278-4343(01)00106-6 

Long, E.R., L.J. Field and D.D. MacDonald. 

1998. Predicting toxicity in marine 

sediments with numerical sediment quality 

guidelines. Environ. Toxicol. Chem. 

17(4):714–727. doi: 10.1897/1551-

5028(1998)017<0714:PTIMSW>2.3.CO;2 

Long, E R., D.D. MacDonald, S.L. Smith and 

F.D. Calder. 1995. Incidence of adverse 

biological effects within ranges of chemical 

concentrations in marine and estuarine 

sediments. Environ. Manage. 19:81–97. 

20
Macdonald, R.W. 1982. An examination of 

metal inputs to the Southern Beaufort Sea by 

disposal of waste barite in drilling fluid. 

Ocean Manage. 8(1):29–49. 

doi:10.1016/0302-184X(82)90012-9 

Macdonald, R.W., A.S. Naidu, M.B. Yunker and 

C. Gobeil. 2004. The Beaufort Sea: 

Distribution, sources, fluxes, and burial rates 

of organic carbon, p. 177–192. In R. Stein 

and R.W. Macdonald [eds.], The Organic 

Carbon Cycle in the Arctic Ocean. Springer, 

Berlin/New York. 

Mucha, A.P., M. Teresa, S.D. Vasconcelos and 

A.A. Bordalo. 2005. Spatial and seasonal 

variations of the macrobenthic community 

and metal contamination in the Douro 

estuary (Portugal). Mar. Environ. Res. 

60(5):531–550. 

doi:10.1016/j.marenvres.2004.12.004 

Naidu, A.S. 1981. Sources, Transport 

Pathways, Depositional Sites and Dynamics 

of Sediments in the Lagoon and Adjacent 

Shallow Marine Region, Northern Arctic 

Alaska. Annual Report to NOAA–OCSEAP 

Office, Boulder, Colorado, 39 p. 

Naidu, A.S. 1985. Organic carbon, nitrogen, 

and C/N ratios of deltaic sediments, North 

Arctic Alaska, p. 311–321. In

SCOPE/UNEP Sonderband Heft 58, Mitt. 

Geol-Paläont. Inst., Univ. Hamburg, 

Germany. 

Naidu, A.S., L.W. Cooper, B.P. Finney, R.W. 

Macdonald, C. Alexander and I.P. 

Semiletov. 2000. Organic carbon isotope 

ratios (δ 13C) of Arctic Amerasian 

continental shelf sediments, p. 522–532. In

R. Stein [ed.], Circum-Arctic River 

Discharge and Its Geological Record, Int. J. 

Earth Sci., Spec. Issue, Vol. 89. 

Naidu, A.S., J.J. Goering, J.J. Kelley and M.I. 

Venkatesan. 2001. Historical Changes in 

Trace Metals and Hydrocarbons in the Inner 

Shelf, Beaufort Sea: Prior and Subsequent to 

Petroleum-Related Industrial Developments. 

Final Report. OCS Study MMS 2001-061, 

University of Alaska Coastal Marine 

Institute, University of Alaska Fairbanks and 

USDOI, MMS, Alaska OCS Region, 80 p. 

Naidu, A.S., J.J. Kelley and J.J. Goering. 2003a. 

Three decades of investigations on heavy 

metals in coastal sediments, North Arctic 

Alaska: A synthesis. J. Phys. IV France 

107:913–916. 

Naidu, A.S., J.J. Kelley, J.J. Goering and M.I. 

Venkatesan. 2003b. Trace Metals and 

Hydrocarbons in Sediments of Elson 

Lagoon (Barrow, Northwest Arctic Alaska) 

as Related to the Prudhoe Bay Industrial 

Region. Final Report. OCS Study MMS 

2003-057, University of Alaska Coastal 

Marine Institute, University of Alaska 

Fairbanks and USDOI, MMS, Alaska OCS 

Region, 33 p. 

Neff, J.M. 2002. Fates and effects of mercury 

from oil and gas exploration and production 

operations in the marine environment. 

Battelle Memorial Institute. Report prepared 

for the American Petroleum Institute, 

Washington, D.C., 136 p. 

NORTECH (Northern Technical Services). 

1981. Beaufort Sea Drilling Effluent 

Disposal Study. Report for SOHIO Alaska 

Petroleum Co., Anchorage, 329 p. 

Philp, R.P. 1985. Fossil Fuel Biomarkers: 

Applications and Spectra. Methods in 

Geochemistry and Geophysics, 23. Elsevier, 

New York, 294 p. 

Simoneit, B.R.T., and I.R. Kaplan. 1980. 

Triterpenoids as molecular indicators of 

paleoseepage in recent sediments of the 

Southern California Bight. Mar. Environ. 

Res. 3(2):113–128. doi:10.1016/0141-

1136(80)90020-3 

Snyder-Conn, E., D. Densmore, C. Moitoret and 

J. Stroebele. 1990. Persistence of trace 

metals in shallow arctic marine sediments 

contaminated by drilling effluents. Oil & 

Chem. Pollut. 7(3):225–247. 

doi:10.1016/S0269-8579(05)80028-0 

21
Steinhauer, M.S., and P.D. Boehm. 1992. The 

composition and distribution of saturated 

and aromatic hydrocarbons in nearshore 

sediments, river sediments, and coastal peat 

of the Alaskan Beaufort Sea: Implications 

for detecting anthropogenic hydrocarbon 

inputs. Mar. Environ. Res. 33(4):223–253. 

doi:10.1016/0141-1136(92)90140-H 

Sweeney, M.D. 1984. Heavy Metals in the 

Sediments of an Arctic Lagoon, Northern 

Alaska. M.S. Thesis, Univ. Alaska 

Fairbanks, 256 p. 

Sweeney, M.D., and A.S. Naidu. 1989. Heavy 

metals in the sediments of the inner shelf of 

the Beaufort Sea, northern arctic Alaska. 

Mar. Pollut. Bull. 20(3):140–143. 

doi:10.1016/0025-326X(88)90820-X 

Thompson, B., B. Anderson, J. Hunt, K. 

Taberski and B. Phillips. 1999. 

Relationships between sediment 

contamination and toxicity in San Francisco 

Bay. Mar. Environ. Res. 48(4–5):285–309. 

doi:10.1016/S0141-1136(99)00060-4 

Trefry, J.H., R.D. Rember, R.P. Trocine and J.S. 

Brown. 2003. Trace metals in sediments 

near offshore oil exploration and production 

sites in the Alaskan Arctic. Environmental 

Geol. 45(2):149–160. doi: 10.1007/s00254-

003-0882-2 

USGS (U.S. Geological Survey) ANWR 

Assessment Team. 1999. The Oil and Gas 

Resource Potential of the Arctic National 

Wildlife Refuge 1002 Area, Alaska. U.S. 

Geolological Survey Open File Report 98–

34. http://energy.cr.usgs.gov/OF98-34 

Valette-Silver, N. [ed.] 1999. Using sediments 

and biota to assess coastal and estuarine 

contamination. Mar. Environ. Res., Spec. 

Issue, Vol. 48(4–5), 494 p. 

Venkatesan, M.I. 1994. Historical Trends in the 

Deposition of Organic Pollutants in the 

Southern California Bight. UCLA, Final 

report to NOAA, 35 p. 

Venkatesan, M.I., S. Brenner, E. Ruth, J. Bonilla 

and I.R. Kaplan. 1980. Hydrocarbons in 

age-dated sediment cores from two basins in 

the Southern California Bight. Geochim. 

Cosmochim. Acta 44(6):789–802. 

doi:10.1016/0016-7037(80)90260-4 

Venkatesan, M.I., and I.R. Kaplan. 1982. 

Distribution and transport of hydrocarbons 

in surface sediments of the Alaskan outer 

continental shelf. Geochim. Cosmochim. 

Acta 46(11):2135–2149. doi:10.1016/0016-

7037(82)90190-9 

Venkatesan, M.I., E. Ruth, S. Steinberg and I.R. 

Kaplan. 1987. Organic geochemistry of 

sediments from the continental margin off 

southern New England, U.S.A. – Part II. 

Lipids. Mar. Chem. 21(3):267–299. 

doi:10.1016/0304-4203(87)90063-6 

Weis, J.S., J. Skurnick and P. Weis. 2004. 

Studies of a contaminated brackish marsh in 

the Hackensack Meadowlands of 

Northeastern New Jersey: Benthic 

communities and metal contamination. Mar. 

Pollut. Bull. 49(11–12):1025–1035. 

doi:10.1016/j.marpolbul.2004.07.006 

Youngblood, W.W., and M. Blumer. 1975. 

Polycyclic aromatic hydrocarbons in the 

environment: Homologous series in soils 

and recent marine sediments. Geochim. 

Cosmochim. Acta 39(9):1303–1314. 

doi:10.1016/0016-7037(75)90137-4 

Zafiriou, O.C., M. Blumer and J. Myers. 1972. 

Correlation of oils and oil products by gas 

chromatography. Woods Hole 

Oceanographic Institution Tech. Rep. 72–

55, 110 p

. 

22
EXECUTIVE SUMMARY 

This project addressed the concern that 

concentrations of trace metals and hydrocarbons 

in the sediments of the Alaskan Arctic can occur 

as a result of petroleum exploration and 

production activities. Lagoon sediments of the 

North Slope, if they were to be the ultimate sink 

for both organic and inorganic anthropogenic 

chemicals, could be a major source of 

contaminants for benthic animals as well as 

organisms which have a close link with 

sediments and which serve as transfer pathways 

of contaminants to higher trophic levels. 

Recognizing the pending lease sales scheduled 

by MMS in 2003–2007 we have extended our 

investigations to establish baselines on trace 

metals and hydrocarbons in the sediments of the 

Beaufort Lagoon located at the remote eastern 

margin of the north Alaskan Arctic coast and far 

from intense industrial activities. 

This report presents the highlights of a twoyear study (2003–2005) which has as its major 

objective the measurement of the concentrations 

of a suite of 12 trace metals (copper (Cu), 

chromium (Cr), cadmium (Cd), nickel (Ni), 

vanadium (V), lead (Pb), tin (Sn), zinc (Zn), 

arsenis (As), barium (Ba), iron (Fe) and 

manganese (Mn) in the mud fraction (<63 um 

size), and total mercury (THg), sediment grain 

size, organic carbon (OC) and hydrocarbons 

(normal and isoprenoid alkanes, triterpenoids 

and steranes and polycyclic aromatic 

hydrocarbons) in the gross sediments of the 

Beaufort Lagoon. The choice of the above 

metals and hydrocarbons is based on the fact 

that these chemicals are often present in drilling 

effluents, crude, and petroleum development and 

production activities. The purpose of this study 

was to close a gap in the baselines for sediment 

metals and hydrocarbons for a remote region of 

the North Slope Coast. 

Sediment samples (Van Veen grab) from the 

Beaufort Lagoon were collected at 22 selected 

stations spread over three sectors. Six of the 

samples were in close proximity to natural oil 

seeps, another six samples from an area that was 

impacted by military activities connected with a 

DEW line station (now defunct), and a third 

suite of 10 samples from east lagoon which is 

presumed pristine. The methods for the analyses 

of the trace metals and hydrocarbons on the 

sediments was essentially the same as those 

adopted in previously supported CMI/MMS 

studies elsewhere along the North Slope 

nearshore region. The QA/QC (quality 

assurance/quality control) protocol prescribed by 

the U.S. Environmental Protection Agency 

(EPA) for metal analysis was followed. QA/QC 

for the organic analyses included successful 

participation in the (NOAA/National Status and 

Trends Program). 

Statistical analysis consisted of the 

determination of the correlation coefficients 

between trace metals, OC, N, and the silt and 

clay percents in the mud fraction to deduce the 

geochemical partitioning of the metals in the 

mud analyzed. Cluster analysis was conducted to 

determine if there were groupings of samples 

based on trace metal concentrations. In addition, 

principal component analysis was conducted to 

deduce the cause of the regional variations in 

metal concentrations. 

Interpretations of the trace metal and 

hydrocarbon data provide the following 

conclusions. There are no significant disparities 

in the metal concentrations between the regions 

exposed to long-term natural oil seep, past 

anthropogenic activities related to the DEW line 

military station and the pristine environment of 

the lagoon. Any of the trace metals investigated 

in this study that might have originated from oil 

seeps or human activity are widely dispersed and 

diluted. The effect of any point sources on the 

metal content in the sediment is not discernable. 

Two time interval comparisons of the mean 

concentrations of metals in muddy sediments 

taken at 26-year intervals (1977–2003) show a 

significant decrease in V, an increase in Mn and 

Cu, and similar values in Cr, Ni and Zn. These 

differences likely reflect the differences in 

granulometry and organic carbon contents 

between the 1977 and 2003 samples. 

The mean concentration of all trace metals 

in the mud of Beaufort Lagoon are generally at 

the same level as those reported by us from the 

23
Colville Delta, Prudhoe Bay-Canning Delta 

region. 

The significantly higher Hg values in 

Beaufort Lagoon gross sediments (mean: 

57ng/g) than in the Colville Delta-Prudhoe BayCanning Delta region (mean: 19 ng/g) are 

probably due to differences in the natural input 

of the metal from the hinterland, a proposition 

that remains to be further investigated. 

Correlation coefficient analysis between 

metals, OC, and granulometry, suggests that 

clays and Fe oxy-hydroxide presumably play an 

important role in metal scavenging and their 

deposition in the Beaufort Lagoon. This 

conclusion is consistent with our results on 

metal partitioning in the adjacent nearshore 

regions of Beaufort Sea. 

Based on principal component analysis, it is 

evident that a southeast-northwest high to low 

gradient is present in the study area in the 

concentrations of the trace metals. This trend 

may be attributed to net regional variations in 

granulometry, organic carbon contents and/or 

possible changes in the natural input of metals 

contents along the above gradients, rather than a 

reflection of a gradient resulting from decreasing 

inputs from potential point sources of 

contaminants, such as from natural oil seeps 

and/or from past activities of the Distant Early 

Warning (DEW) line station located south of 

Nuvagapak Point. 

The hydrocarbon components in gross 

sediments from the Beaufort Lagoon are 

biogenic and terrestrial. Their general 

composition is very similar to those found in the 

sediments from Elson Lagoon, Colville Delta, 

Prudhoe Bay, Canning Delta and adjacent 

Canadian deltaic and inner shelf region and the 

inner shelf of the Beaufort Sea. The data provide 

no evidence to document the contribution of 

petroleum hydrocarbons to the Beaufort Lagoon 

sediments analyzed from the oil seeps located in 

the vicinity and anthropogenic activities. The 

trace metal and hydrocarbon levels are either 

similar to or below those reported for unpolluted 

near-shore regions of the world. The Beaufort 

Lagoon sediments have remained 

uncontaminated as far as the analyzed trace 

metals and hydrocarbons are concerned. 

The mean concentrations of As, Cu and Ni 

in the mud of the Beaufort Lagoon are above the 

threshold level of the Effects Range-low (ERL), 

as stated in Long et al., (1995, 1998), that can 

cause adverse effects on benthic and demersal 

organisms. However, the mean concentrations of 

all the selected 14 hydrocarbons in the gross 

sediments of Beaufort Lagoon are below the 

ERL, which implies that no adverse effects can 

be expected from current levels of hydrocarbons 

on the above organisms.

24
Figure 1: Study area showing locations of sediment samples in the Beaufort Lagoon. 

25
Figure 2: Map showing the study area (in filled rectangle) relative to the Arctic National Wildlife Refuge 

(ANWR) including the coastal plain unit.

26
 Figure 3: Boxplots of standardized concentrations of 12 metals in Beaufort Lagoon sediments.

27
 

 Figure 4: Dotplots of metal concentrations for 12 metals by station in Beaufort Lagoon. 

28
Figure 5: Dendrogram showing Ward's linkage clustering (Euclidean distances) based on 

concentrations of 12 metals measured at each station.

29
Figure 6: Map showing relative locations of stations (coastline not shown) and group 

membership corresponding to clusters as shown in Figure 5. Stations BL03-4 and 

BL03-17 (circled) did not cluster with any other stations.

30
Figure 7: Dotplots of metal concentrations for 12 metals by cluster (see Fig. 5 for clusters).

31
 

 Figure 8: Cumulative amount of variance explained by the first ten Principal Components. 

32
Figure 9: Beaufort Lagoon stations in the space of the first two principal components. Groups 

identified by a cluster analysis (see Fig. 5) are indicated. 

33
Figure 10: Partial fit of PC 1 on silt in mud fraction after accounting for effects of latitude (stations 

BL03-4 and BL03-17 were excluded from regression). 

34
Figure 11: Partial fit of PC 1 on latitude after accounting for effects of silt in mud fraction (stations 

BL03-4 and BL03-17 were excluded from regression).

35
36

Figure 12: Linear regression of PC 2 on percentage of mud in sediment (stations BL03-4 and 

BL03-17 were excluded from regression). Red points show mean values of PC 2 corresponding 

to mud concentrations below and above 50%.
Table 1: Sample locations, grain sizes, organic carbon (OC), nitrogen (N), OC/N, and stable isotopes of OC (δ13C ‰) 

Beaufort Lagoon sediments. 

Sample Lat °N Long °W Solids % Gravel % Sand % Silt % Clay % Mud % OC % N % O

BL03-1 69.87 142.23 53.4 0.00 6.43 77.39 16.18 93.57 2.39 0.22 10BL03-2 69.87 142.26 67.9 0.00 42.28 36.63 21.09 57.72 2.33 0.20 1BL03-3 69.89 142.33 51.9 0.00 18.11 51.87 30.02 81.89 2.17 0.20 10BL03-4 69.91 142.24 79.5 0.00 95.55 0.09 4.36 4.45 1.72 0.17 10BL03-4B 69.89 142.33 91.5 92.87 2.54 1.92 2.66 4.59 3.29 0.32 10BL03-5 69.93 142.36 99.10 NA NA NA NA NA NA NA BL03-5B 69.86 142.18 52.9 0.00 13.94 50.36 35.70 86.06 2.00 0.18 1BL03-6B 69.87 142.22 56.8 0.00 6.56 50.22 43.22 93.44 2.02 0.19 10BL03-9 69.88 142.27 61.2 0.28 33.60 42.13 23.98 66.12 3.96 0.36 1BL03-9B 69.87 142.19 65.0 0.00 27.86 48.44 23.69 72.14 2.27 0.19 1BL03-10 69.91 142.33 74.9 0.00 81.25 13.24 5.50 18.75 2.38 0.20 1BL03-11A 69.87 142.20 61.9 0.00 22.51 55.19 22.30 77.49 1.55 0.13 1BL03-12 69.92 142.37 61.4 0.00 19.01 58.97 22.02 80.99 2.04 0.17 12BL03-13 69.92 142.36 76.6 0.00 89.76 7.45 2.79 10.24 1.43 0.12 1BL03-14 69.92 142.34 67.0 0.00 77.97 9.18 12.85 22.03 1.66 0.15 1BL03-15 69.92 142.34 NA 0.00 83.42 3.15 13.42 16.58 1.76 0.17 10BL03-16 69.88 142.28 43.8 0.00 24.24 52.46 23.30 75.76 3.20 0.26 12BL03-17 69.87 142.28 79.6 0.12 97.88 0.05 1.95 1.99 2.57 0.30 8BL03-18 69.89 142.29 56.4 0.00 25.17 36.81 38.02 74.83 2.60 0.23 1BL03-19 69.89 142.31 89.8 28.60 63.62 1.34 6.45 7.78 4.05 0.38 10BL03-20 69.88 142.32 79.3 37.75 58.80 0.72 2.73 3.45 3.75 0.37 10OS 69.88 142.31 NA NA NA NA NA NA NA NA 

37
Table 2: Concentrations of metals in Beaufort Lagoon sediments. All are μg/g, except Hg (ng/g) and Fe (%). 

Sample V μg/g Cr Mn Ni Cu Zn As Cd Sn Ba Pb μg/g 

BL03-1 110 68.6 318 36.9 38.5 98.4 10.9 0.224 1.78 559 16.8 BL03-2 121 73.7 506 37.0 34.9 105 17.7 0.195 1.83 585 16.8 BL03-3 127 72.7 311 40.6 42.3 110 18.4 0.233 1.76 512 19.1 BL03-4 87.3 55.5 1222 27.2 19.9 60.2 10.0 0.196 1.53 355 11.0 BL03-4B 136 78.2 668 44.9 44.3 107 20.3 0.345 2.65 511 19.1 BL03-5 94.7 59.9 182 25.7 16.2 48.2 6.9 0.085 1.32 436 12.0 BL03-5B 121 71.4 407 41.8 44.0 107 15.8 0.286 1.73 583 18.5 BL03-6B 129 76.9 319 41.2 43.0 111 17.0 0.266 2.01 592 19.9 BL03-9 123 74.2 339 40.0 39.2 100 12.8 0.242 1.69 530 16.7 BL03-9B 131 83.8 370 45.0 44.7 107 12.5 0.287 1.83 649 18.6 BL03-10 106 71.1 457 32.7 28.5 80.4 11.7 0.246 1.60 473 13.1 BL03-11A 116 71.5 305 37.7 36.1 89.1 12.0 0.206 1.80 550 15.7 BL03-12 118 72.2 364 35.2 33.0 88.5 13.9 0.232 1.68 592 15.2 BL03-13 115 73.0 503 35.0 29.7 79.5 13.3 0.190 1.74 329 13.8 BL03-14 120 70.2 359 37.1 34.6 85.5 12.8 0.223 1.71 446 15.1 BL03-16 113 67.9 351 37.3 32.1 81.9 14.2 0.214 1.58 413 13.4 BL03-17 131 74.1 3132 54.3 55.2 93.3 16.4 0.341 4.86 430 28.7 BL03-18 136 81.7 346 42.2 37.9 104 16.8 0.207 1.88 572 18.3 BL03-19 125 82.2 868 43.0 41.2 107 16.4 0.623 3.99 479 23.1 BL03-20 136 81.3 829 50.8 40.8 111 15.0 0.454 4.13 496 20.3 A-Mean 120 73.0 608 39.0 37.0 94 14.0 0.265 2.00 505 17.0 Std AM 13 7.0 643 6.8 8.9 17 3.2 0.110 0.98 85 4.1 G-Mean 119 73.0 472 39.0 36.0 92 14.0 0.246 2.00 497 17.0 Std GM 13 7.0 658 6.9 9.0 17 3.2 0.110 0.99 85 4.1 % CV 11 9.7 139 17.7 25.2 19 23.2 46.400 49.40 17 24.3 

38

A-Mean: Arithmetic mean Std AM: Standard deviation of arithmetic mean G-Mean: Geometric mean Std GM: Standard deviation of geometric mean % CV: Percent coefficient of variation 
Table 3: Results of the QA/QC analysis concerning calibration verification. 

Analyte (unit) Batch ID ICV-TV ICV-Obs ICV-Rec CCV1-TV CCV1-Obs CCV1-Rec CCV2-TV CCV (μg/L) A 50 45.3523091 90.7046182 10 10.10702359 101.0702359 10 9.8Cr A 50 46.96249819 93.92499637 10 10.42038436 104.2038436 10 10.3Mn A 50 45.61942801 91.23885601 10 10.47879367 104.7879367 10 10.2Fe A 100 73.05313706 73.05313706 50.00000381 39.06361265 78.12721935 50.00000381 38.6Ni A 50 50.8867821 101.7735642 10 10.68007653 106.8007653 10 10.6Cu A 50 50.30532361 100.6106472 10 10.60041579 106.0041579 10 10.4Zn A 50 51.36481686 102.7296337 20 20.94026515 104.7013258 20 20.4As A 50 45.45553065 90.91106131 10 10.38048842 103.8048842 10 10.0Cd A 5 4.649514064 92.99028129 1 1.029401306 102.9401306 1 1.0Sn A 50 53.76962124 107.5392425 2.003951832 1.9Ba A 100 97.20926536 97.20926536 10 9.892735523 98.92735523 10 9.7Pb (μg/L) A 5 5.148574426 102.9714885 2 2.219005835 110.9502917 2 2.1THg (ng/L) B 15 15.14149028 100.9432685 20 19.85846544 99.29232721 20 20.0Analyte (unit) Batch ID CCV3-TV CCV3-Obs CCV3-Rec CCV4-TV CCV4-Obs CCV4-Rec CCV5-TV CCV (μ/L) A 10 9.991375273 99.91375273 10 10.17824322 101.7824322 10 9.9Cr A 10 10.23747284 102.3747284 10 10.43125707 104.3125707 10 10.2Mn A 10 10.15512333 101.5512333 10 10.37120146 103.7120146 10 10.3Fe A 50.00000381 36.14374571 72.28748591 50.00000381 38.91393305 77.82786016 50.00000381 37.1Ni A 10 10.50028633 105.0028633 10 10.74240442 107.4240442 10 10.5Cu A 10 10.44103275 104.4103275 10 10.48291771 104.8291771 10 10.4Zn A 20 20.84492497 104.2246249 20 20.58320021 102.9160011 20 20.7As A 10 10.07112922 100.7112922 10 10.24800377 102.4800377 10 9.9Cd A 1 1.025773372 102.5773372 1 1.021258889 102.1258889 1 1.0Sn A 1.928422781 1.926497615 1.8Ba A 10 9.859105991 98.59105991 10 9.892031641 98.92031641 10 9.6Pb (μg/L) A 2 2.169817453 108.4908727 2 2.173315751 108.6657876 2 2.1THg (ng/L) B 20 20.16609426 100.8304713 20 20.2686372 101.343186 Analyte (unit) Batch ID CCV6-TV CCV6-Obs CCV6-Rec CCV7-TV CCV7-Obs CCV7-Rec CCV8-TV CCV (μg/L) A 10 9.849617357 98.49617357 10 9.783745819 97.83745819 10 9.5Cr A 10 10.1783771 101.783771 10 10.02781438 100.2781438 10 9.8Mn A 10 10.09998875 100.9998875 10 10.10092558 101.0092558 10 9.8Fe A 50.00000381 38.19419485 76.38838388 50.00000381 36.77596348 73.55192136 50.00000381 37.0Ni A 10 10.36700825 103.6700825 10 10.13588373 101.3588373 10 9.8Cu A 10 10.31545979 103.1545979 10 10.4797927 104.797927 10 10.4Zn A 20 20.23273385 101.1636692 20 21.04050314 105.2025157 20 20.6As A 10 9.847302208 98.47302208 10 9.983570755 99.83570755 10 9.7Cd A 1 1.002141532 100.2141532 1 1.031852437 103.1852437 1 0.9Sn A 1.887518769 1.858317909 1.8Ba A 10 9.763108636 97.63108636 10 9.730458986 97.30458986 10 9.6Pb (μg/L) A 2 2.09613605 104.8068025 2 2.12493247 106.2466235 2 2.1THg (ng/L) B 

39
Table 3. (cont.) 

Analyte (unit) Batch ID CCV9-TV CCV9-Obs CCV9-Rec CCV10-TV CCV10-Obs CCV10-Rec CCV11-TV CCV (μg/L) A 10 9.650594968 96.50594968 10 9.30736503 93.0736503 10 9.4Cr A 10 9.76573373 97.6573373 10 9.544484373 95.44484373 10 9.6Mn A 10 9.827188222 98.27188222 10 9.458645312 94.58645312 10 9.6Fe A 50.00000381 39.53449401 79.06898199 50.00000381 42.37362985 84.74725323 50.00000381 47.0Ni A 10 9.932683621 99.32683621 10 9.576026001 95.76026001 10 9.6Cu A 10 10.2025627 102.025627 10 9.890386321 98.90386321 10 10.0Zn A 20 20.3137235 101.5686175 20 19.52618759 97.63093797 20 19.5As A 10 9.585721832 95.85721832 10 9.299644052 92.99644052 10 9.4Cd A 1 0.989542451 98.9542451 1 0.947602132 94.76021317 1 0.9Sn A 1.918633807 1.824633062 1.9Ba A 10 9.838818362 98.38818362 10 9.148799712 91.48799712 10 9.6Pb (μg/L) A 2 2.12562117 106.2810585 2 2.025839268 101.2919634 2 2.1THg (ng/L) B Analyte (unit) Batch ID CCV12-TV CCV12-Obs CCV12-Rec CCV13-TV CCV13-Obs CCV13-Rec CCV14-TV CCV (μg/L) A 10 9.438779146 94.38779146 10 10.11357487 101.1357487 10 10.0Cr A 10 9.5126383 95.126383 10 10.31263132 103.1263132 10 10.2Mn A 10 9.651176105 96.51176105 10 10.29423463 102.9423463 10 10.1Fe A 50.00000381 53.94851826 107.8970283 50.00000381 43.16024445 86.32048232 50.00000381 38.8Ni A 10 9.577118118 95.77118118 10 10.4172239 104.172239 10 10.2Cu A 10 9.803673602 98.03673602 10 10.22385582 102.2385582 10 10.2Zn A 20 19.1865418 95.93270898 20 20.44292065 102.2146032 20 20.3As A 10 9.149850875 91.49850875 10 9.69797573 96.9797573 10 9.6Cd A 1 0.947509367 94.75093668 1 1.017795471 101.7795471 1 0.9Sn A 1.87476249 1.934516221 1.9Ba A 10 9.423369849 94.23369849 10 9.725311342 97.25311342 10 9.5Pb (μg/L) A 2 2.101084924 105.0542462 2 2.142351295 107.1175648 2 2.1THg (ng/L) B 

40
41

Table 4: Results of the QA/QC analysis concerning calibration blanks. 

Analyte (unit) Batch ID ICB CCB1 CCB2 CCB3 CCB4 CCB5 CCV (μg/L) A –0.019412662 –0.022915678 0.003640651 0.017759003 0.048708424 0.023439894 0.0243Cr A –0.002122966 0.003766614 0.010165725 –0.002818597 –0.009003925 –0.023367497 –0.0305Mn A 0.001514224 –0.000366763 0.001696906 0.000215278 0.001268211 –0.000454617 0.0010Fe A –1.281956901 2.199543674 2.977579904 2.51391155 1.110781557 0.8398272 0.8799Ni A 0.006692471 0.001049361 0.003343839 0.001642198 0.001944399 0.002645204 0.0018Cu A –0.002534501 –0.01197791 –0.016823747 –0.010802005 –0.007336244 –0.004534008 –0.0053Zn A 0.009717066 –0.007442436 0.000322795 0.006762036 –0.006444729 0.008655965 0.0067As A 0.03487219 0.023736137 0.056976428 0.045339725 0.040974748 0.03895845 0.0788Cd A 0.001390389 0.00066378 8.54564E–05 0.000269234 –0.000194387 0.000389272 –0.0002Sn A 0.247473511 0.019964263 0.023887361 0.026699068 0.02564591 0.020272009 0.0281Ba A 0.010189992 0.001502795 0.000655891 0.000560007 0.001351205 0.001324258 0.0020Pb (μg/L) A 0.000486244 0.000574009 0.000689952 0.000983047 0.000643604 0.000557415 0.0002THg (ng/L) B 0.005127147 0.010254294 0.020508588 0.076907204 0.061525765 Analyte (unit) Batch ID CCB8 CCB9 CCB10 CCB11 CCB12 CCV (μg/L) A –0.010947072 –0.016725359 0.011709312 0.027295459 0.010289739 –0.0139Cr A –0.056714697 –0.075768997 –0.066915037 –0.094584515 –0.116960163 –0.1312Mn A –0.001074566 0.002161963 0.03136897 0.054314014 0.051490255 0.0154Fe A 2.653762053 2.800329156 9.014763907 14.93157478 8.144938152 1.3419Ni A 0.012223274 0.01125807 0.033918849 0.047015877 0.046362983 0.0631Cu A –0.008492945 –0.000696379 0.013466952 0.027762757 0.027535099 0.0061Zn A 0.033953836 0.038064624 0.099442749 0.102272735 0.1616685 1.1125As A 0.061924645 0.084226575 0.115874334 0.115621475 0.148838907 0.0731Cd A –1.18679E–05 0.000420587 0.002093238 0.003724701 0.004472952 0.0002Sn A 0.020168967 0.01414789 0.033233545 0.026029557 0.025150975 0.0130Ba A 0.000679496 0.001074303 0.025160283 0.044806803 0.045522298 0.0113Pb (μg/L) A –0.000259981 –0.000394815 0.004911209 0.009329379 0.009550545 0.0052THg (ng/L) B 
Table 5: Results of the QA/QC analysis concerning spikes. 

Analyte 

(unit) 

Batch 

ID 

Sample

ID Mean Spike 

TV 

Dup 

Spike 

TV 

Obs 

Spike 

Value 

Dup Obs 

Spike 

Value 

Spike 

% Rec 

Dup 

Spike 

% Rec 

RPD 

V (mg/kg) A BL03-4 87.22 98.81 98.81 190.0 190.8 104.0 104.8 0.7 

V A BL03-3 126.6 79.37 79.68 205.3 207.9 99.1 102.0 2.9 

Cr A BL03-4 55.07 98.81 98.81 157.7 158.3 103.8 104.4 0.6 

Cr A BL03-3 72.52 79.37 79.68 145.8 142.0 92.3 87.2 5.7 

Mn A BL03-4 1215 98.81 98.81 1324 1324 110.4 109.6 0.8 

Mn A BL03-3 312.4 79.37 79.68 385.4 394.4 92.1 102.9 11.1 

Fe A BL03-3 30902 79.37 79.68 32448 30620 1949 –353.9 288.8 

Fe A BL03-4 21899 494.1 494.1 22701 22647 162.3 151.4 6.9 

Ni A BL03-3 40.88 79.37 79.68 124.0 126.3 104.8 107.2 2.3 

Ni A BL03-4 27.48 123.5 123.5 154.7 156.6 103.0 104.5 1.4 

Cu A BL03-4 20.40 123.5 123.5 148.1 146.4 103.4 102.0 1.4 

Cu A BL03-3 42.67 79.37 79.68 127.3 128.1 106.7 107.2 0.5 

Zn A BL03-3 111.6 79.37 79.68 187.8 188.3 96.1 96.3 0.2 

Zn A BL03-4 60.59 247.0 247.0 311.7 313.3 101.6 102.3 0.6 

As A BL03-3 18.48 79.37 79.68 91.56 92.81 92.1 93.3 1.3 

As A BL03-4 9.84 98.81 98.81 113.1 111.9 104.5 103.3 1.1 

Cd A BL03-3 0.229 79.37 79.68 76.35 76.99 95.9 96.3 0.4 

Cd A BL03-4 0.196 9.881 9.881 10.47 10.27 103.9 101.9 2.0 

Sn A BL03-3 1.774 79.37 79.68 80.55 79.81 99.3 97.9 1.3 

Sn A BL03-4 1.523 24.70 24.70 27.54 26.69 105.3 101.9 3.3 

Ba A BL03-3 497.2 79.37 79.68 596.7 521.8 125.4 30.9 120.9 

Ba A BL03-4 357.1 197.6 197.6 578.6 576.8 112.1 111.2 0.8 

Pb A BL03-3 19.08 79.37 79.68 98.77 98.35 100.4 99.5 0.9 

Pb (mg/kg) A BL03-4 11.04 24.70 24.70 35.68 35.48 99.7 99.0 0.8 

THg (ng/g) B BL03-4 12.62 48.75 50.20 59.84 61.63 96.9 97.6 0.8 

42
Table 6: Results of the QA/QC analysis concerning replicates (precision determination). 

Analyte (unit) Batch ID Sample ID Sample Duplicate Mean RPD 

V (mg/kg) A BL03-4 87.28 87.17 87.22 0.1 

V A BL03-3 127.0 126.2 126.6 0.6 

Cr A BL03-4 55.46 54.68 55.07 1.4 

Cr A BL03-3 72.70 72.35 72.52 0.5 

Mn A BL03-4 1222 1209 1215 1.1 

Mn A BL03-3 310.5 314.3 312.4 1.2 

Fe A BL03-3 30998 30805 30902 0.6 

Fe A BL03-4 22087 21711 21899 1.7 

Ni A BL03-3 40.63 41.13 40.88 1.2 

Ni A BL03-4 27.23 27.74 27.48 1.8 

Cu A BL03-4 19.87 20.94 20.40 5.3 

Cu A BL03-3 42.27 43.07 42.67 1.9 

Zn A BL03-3 110.4 112.8 111.6 2.1 

Zn A BL03-4 60.21 60.96 60.59 1.2 

As A BL03-3 18.36 18.60 18.48 1.3 

As A BL03-4 9.97 9.71 9.84 2.6 

Cd A BL03-3 0.233 0.225 0.229 3.4 

Cd A BL03-4 0.196 0.196 0.196 0.2 

Sn A BL03-3 1.76 1.79 1.77 1.6 

Sn A BL03-4 1.53 1.51 1.52 1.1 

Ba A BL03-3 511.6 482.8 497.2 5.8 

Ba A BL03-4 355.0 359.2 357.1 1.2 

Pb A BL03-3 19.10 19.05 19.08 0.2 

Pb (mg/kg) A BL03-4 11.03 11.05 11.04 0.2 

THg (ng/g) B BL03-4 11.68 13.56 12.62 14.9 

% Total Solids C BL03-4 79.5 78.9 79.2 0.8 

% Total Solids C BL03-17 79.6 79.5 79.6 0.1 

43
44

Table 7: Results of the QA/QC analysis concerning analytical accuracy using 

certified reference materials, NIST 2709 and IAEA 405. 

Analyte (unit) Batch ID CRM Identity Cert Value Obs Value % Rec 

V (mg/kg) A NIST 2709 112.00 97.12 86.7 

V A BlankSpike 80.00 85.78 107.2 

V A IAEA 405 95.00 90.21 95.0 

Cr A IAEA 405 84.00 67.42 80.3 

Cr A BlankSpike 80.00 86.14 107.7 

Cr A NIST 2709 130.00 93.28 71.8 

Mn A NIST 2709 538.00 420.18 78.1 

Mn A IAEA 405 495.00 384.99 77.8 

Mn A BlankSpike 80.00 87.95 109.9 

Fe A BlankSpike 80.00 58.29 72.9 

Fe A NIST 2709 35000.00 28463.83 81.3 

Fe A IAEA 405 37400.00 29885.25 79.9 

Ni A IAEA 405 32.50 32.42 99.8 

Ni A BlankSpike 80.00 93.66 117.1 

Ni A NIST 2709 88.00 76.19 86.6 

Cu A BlankSpike 80.00 89.09 111.4 

Cu A NIST 2709 34.60 37.34 107.9 

Cu A IAEA 405 47.70 54.28 113.8 

Zn A IAEA 405 279.00 281.40 100.9 

Zn A NIST 2709 106.00 106.90 100.8 

Zn A BlankSpike 80.00 83.51 104.4 

As A NIST 2709 17.70 16.84 95.1 

As A IAEA 405 23.60 23.47 99.5 

As A BlankSpike 80.00 75.32 94.2 

Cd A BlankSpike 80.00 78.38 98.0 

Cd A NIST 2709 0.38 0.65 172.1 

Cd A IAEA 405 0.73 0.74 101.8 

Sn A IAEA 405 7.60 9.54 125.5 

Sn A BlankSpike 80.00 79.93 99.9 

Ba A NIST 2709 968.00 845.36 87.3 

Ba A BlankSpike 80.00 97.11 121.4 

Pb A NIST 2709 18.90 19.29 102.1 

Pb A IAEA 405 74.80 77.83 104.0 

Pb (mg/kg) A BlankSpike 80.00 78.63 98.3 

THg (ng/g) B IAEA 405 810.00 765.78 94.5 
Table 8: Correlation coefficients for chemical and physical parameters of muds from Beaufort Lagoon (N = 19; significan

shown in bold and insignificant correlations are in gray). 

45 

V Cr Mn Ni Cu Zn As Cd Sn Ba Pb Fe OC % 

V 1.00 Cr 0.89 1.00 Mn 0.07 –0.07 1.00 Ni 0.85 0.71 0.48 1.00 Cu 0.80 0.64 0.39 0.91 1.00 Zn 0.84 0.78 –0.16 0.69 0.76 1.00 As 0.72 0.52 0.12 0.55 0.58 0.68 1.00 Cd 0.41 0.54 0.30 0.57 0.45 0.45 0.31 1.00 Sn 0.48 0.43 0.74 0.78 0.61 0.35 0.40 0.78 1.00 Ba 0.53 0.57 –0.38 0.31 0.47 0.70 0.26 0.08 –0.12 1.00 Pb 0.70 0.50 0.80 0.89 0.92 0.58 0.68 0.63 0.86 0.10 1.00 Fe 0.73 0.85 0.28 0.58 0.62 0.77 0.71 0.59 0.50 0.48 0.70 1.00 

OC % 0.37 0.40 0.12 0.42 0.31 0.62 0.44 0.66 0.46 0.07 0.38 0.44 1.00 Silt % –0.63 –0.40 –0.75 –0.81 –0.73 –0.51 –0.72 –0.73 –0.93 0.19 –0.88 –0.52 –0.44 Clay % 0.64 0.40 0.74 0.82 0.75 0.55 0.72 0.72 0.93 –0.17 0.88 0.52 0.58 
46

_

X

_

X

Table 9: Time-interval changes in the mean concentrations (μg/g dry wt) 

of trace metals in sediments of Beaufort Lagoon.a

Year V Cr Mn Ni Cu Zi 

Table 9: Time-interval changes in the mean concentrations (μg/g dry wt) 

of trace metals in sediments of Beaufort Lagoon.a

1977b

N=5 

139 69 359 48 22 81 

SD 17 12 69 6 4 11 

CV% 12 17 19 13 18 14 

2003c

N=21 

119 73 472 39 36 92 

SD 13 7 659 7 9 17 

CV% 11 10 139 18 25 19 

a

Significant differences (p<0.05) in bold 

b

Naidu [1981] 

c

This study (Table 2) 
Table 10: Distribution (ng/g dry wt) of n-alkanes in gross sediments of Beaufort Lagoon. All sample numbers have the p

Sample ID – UCLA No. 1 2 3 3D* 4 4R* 5B 6B 9 9B 9BD* Surrogate Recovery (%) Deu C14 nd$ 52 52 53 56 57 53 55 52 62 62 Deu C24 nd$ 66 67 69 69 64 70 63 65 76 76 Deu C36 nd$ 67 78 75 61 66 72 65 66 66 79 n-alkane (ng/g dry wt)n-C10 nd nd nd nd nd nd nd nd nd nd nd n-C11 nd nd nd nd nd nd 62.9 217.6 nd nd nd n-C12 nd nd nd nd nd nd nd nd nd nd nd n-C13 nd nd nd nd nd nd nd nd nd nd nd n-C14 nd nd nd nd nd nd nd nd nd nd nd n-C15 67.1 34.4 60.7 52.6 nd nd 38.7 72.3 45.5 41.1 30.7 n-C16 96.2 26.0 56.6 41.9 nd nd 32.8 62.5 56.9 50.9 40.5 n-C17 184.3 70.9 192.5 172.5 3.2 3.8 117.0 198.8 192.8 98.5 76.0 pr nd nd nd nd nd nd nd nd nd nd nd n-C18 89.6 38.2 108.7 98.0 1.8 2.2 63.5 110.4 102.0 54.3 46.2 ph nd nd nd nd nd nd nd nd nd nd nd n-C19 280.1 99.8 317.3 287.4 3.8 4.6 181.5 307.2 321.8 162.1 140.2 n-C20 166.5 65.2 198.8 180.4 2.8 3.4 116.9 202.4 191.1 110.5 96.5 n-C21 579.0 204.2 630.6 584.7 7.3 7.5 382.1 627.9 623.2 360.7 316.3 1n-C22 312.8 116.1 323.6 311.7 5.1 5.7 196.5 332.7 330.7 196.8 180.1 n-C23 990.9 354.0 1056.6 974.1 13.2 14.9 672.8 1068.7 995.0 676.7 605.0 3n-C24 268.7 105.7 287.0 294.6 5.6 6.0 186.8 318.7 305.5 188.1 184.1 n-C25 826.3 341.2 839.9 814.5 14.9 14.6 573.5 951.2 819.1 735.8 661.7 3n-C26 126.6 58.2 153.8 146.9 3.9 3.6 103.0 178.8 146.2 112.4 109.5 n-C27 1015.9 472.0 1483.4 1450.0 18.1 18.5 867.3 1239.8 1738.7 1496.4 1370.4 4n-C28 73.3 34.5 94.5 176.6 3.5 3.4 70.0 120.0 80.1 81.0 144.5 n-C29 886.5 376.5 1217.9 1346.5 17.9 18.6 933.4 1323.9 1054.3 1160.3 1450.2 4n-C30 83.2 29.9 128.9 141.1 3.6 2.8 79.0 129.8 35.0 100.8 116.7 n-C31 749.0 308.8 1190.4 1330.8 18.4 18.4 889.2 1312.5 938.5 988.7 1152.2 3n-C32 146.2 46.7 82.0 39.4 1.8 2.0 49.0 86.0 41.5 68.5 39.2 n-C33 210.3 90.1 378.7 444.7 7.1 7.1 274.4 424.7 264.6 300.5 375.4 1n-C34 nd 26.7 58.2 63.3 2.4 2.0 nd 67.6 80.1 nd 47.9 n-C35 nd nd nd 44.7 2.0 2.6 nd nd nd nd nd n-C36 nd nd nd nd nd nd nd nd nd nd nd Total n-alkanes (ng/g dry wt) 7152.4 2899.1 8860.1 8996.4 136.5 142.0 5890.2 9353.3 8362.6 6984.2 7183.3 27Σ C12–C19 (ng/g dry wt) 717.3 269.4 735.9 652.3 8.8 10.7 433.5 751.2 719.0 407.0 333.5 1Σ C20–C33 (ng/dry wt) 6435.1 2603.0 8066.0 8236.0 123.2 126.7 5393.8 8316.9 7563.5 6577.3 6801.8 25Pr/Ph nd nd nd nd nd nd nd nd nd nd nd Odd/Even** 4.2 4.3 4.9 5.0 3.5 3.5 5.5 4.7 5.1 6.3 6.1 

47
Table 10. (cont.) 

Sample ID – UCLA No. 13 14 15 16 17 18 19 20 OS# Pr. Blk XSPIKE 1 % Recovery Surrogate Recovery (%) Deu C14 57 55 58 nd$ 53 58 60 54 nd$ 51 52 Deu C24 76 64 61 nd$ 65 68 61 66 nd$ 57 64 Deu C36 80 65 58 nd$ 92 70 65 68 nd$ 66 74 n-alkane (ng/g dry wt)

μg/g dry 

wt 

n-C10 nd nd nd nd nd nd 25.4 nd 499.6 nd 18 n-C11 nd nd nd nd nd nd 34.2 nd 3761.2 nd 28 n-C12 nd nd nd nd nd nd 17.3 nd 489.6 nd 33 n-C13 nd 32.2 nd nd nd nd nd nd 253.8 nd 40 n-C14 nd 27.2 nd nd nd nd nd nd 148.3 nd 50 n-C15 74.2 66.1 nd nd 2.7 31.7 14.9 17.0 65.0 nd 57 n-C16 55.7 53.9 nd 223.8 2.0 31.4 15.2 9.6 nd nd 66 n-C17 170.8 144.6 75.4 754.9 5.7 103.6 66.4 37.1 nd nd 65 pr nd 38.7 nd nd nd 13.1 7.7 nd nd nd 67 n-C18 94.4 80.1 41.0 339.8 3.9 58.9 37.5 19.1 nd nd 69 ph nd 18.4 nd nd nd nd nd nd nd nd 69 n-C19 36.0 208.0 103.7 1141.0 1.9 174.1 122.4 62.6 nd nd 70 n-C20 146.1 147.8 73.7 680.8 5.3 112.2 76.4 36.1 58.1 1.51 72 n-C21 421.2 464.0 227.0 2275.8 13.9 364.2 246.9 109.3 86.9 nd 72 n-C22 36.9 260.3 138.3 1238.2 7.5 199.6 127.8 61.3 53.2 nd 76 n-C23 831.6 834.4 444.2 4079.3 20.6 630.8 400.8 167.0 67.6 nd 69 n-C24 35.0 250.1 142.8 1116.4 6.9 186.7 112.7 51.3 71.8 nd 60 n-C25 911.3 888.6 491.9 3918.1 19.4 556.5 349.5 136.0 218.4 nd 65 n-C26 191.3 124.6 86.3 574.5 4.2 100.5 52.0 27.0 87.9 nd 70 n-C27 1608.1 1718.1 863.0 5131.4 20.6 1085.1 369.4 146.4 179.1 nd 69 n-C28 159.2 97.3 65.5 328.6 3.1 64.3 26.1 15.5 60.2 nd 66 n-C29 1628.0 1538.0 682.9 4763.2 25.7 855.6 325.2 143.7 138.0 nd 66 n-C30 149.4 98.4 60.2 334.1 2.2 93.1 41.0 20.4 230.1 nd 66 n-C31 1621.1 1150.4 600.7 4488.1 25.2 861.2 339.9 156.5 171.2 nd 67 n-C32 68.6 32.3 0.0 784.7 0.0 26.2 15.1 11.8 169.6 nd 64 n-C33 564.4 354.9 195.2 1339.2 8.3 271.3 110.5 51.0 nd nd 66 n-C34 49.4 52.6 nd 330.4 nd 45.8 29.9 13.5 nd nd 64 n-C35 75.2 30.2 nd nd nd 24.4 10.9 nd nd nd 60 n-C36 nd nd nd nd nd nd nd nd nd nd 69 Total n-alkanes (ng/g dry wt) 8927.9 8654.2 4291.7 33842.3 179.2 5877.3 2967.7 1292.1 6819.4 Σ C12–C19 (ng/g dry wt) 431.1 612.2 220.1 2459.5 16.1 399.7 273.8 145.3 956.6 Σ C20–C33 (ng/g dry wt) 8372.3 7959.2 4071.7 31052.4 163.1 5407.4 2593.5 1133.3 1602.1 Pr/Ph nd 2.1 nd nd nd na† na† nd nd Odd/Even** 8.1 6.2 6.1 4.7 4.1 5.4 4.4 3.9 1.3 

* Duplicate (D) or 

** Summed n-C15–

# OS=oil spill sam

 of concentratind$=dilution too g

nd=not detected na†=not applicable

48
Table 11: Distribution (ng/g dry wt) of PAHs in gross sediments of Beaufort Lagoon. All lagoon sample numbers have the 

Sample ID – UCLA No. 1 2 3 3D* 4 5B 6B 1 2 3 3Surrogate Recovery (%) PAH (ng g–1 dry wt) (cont.) hexamethylbenzene 62 53 50 50 38 41 44 C3-fluoranthenes/pyrenes 4.9 2.6 2.2 n-dodecylbenzene 57 58 62 64 59 59 60 C4-fluoranthenes/pyrenes nd 1.7 3.3 4-terphenyl-D14 64 60 75 68 68 65 57 benz(a)anthracene 4.0 1.4 2.7 

chrysene/triphenylene 12.0 8.0 14.8 1

PAH (ng g–1 dry wt) C1-chrysenes/triphenylenes 7.9 9.2 12.5 1naphthalene 7.7 7.4 13.0 16.7 nd 7.3 6.7 C2-chrysenes/triphenylenes 2.6 4.3 6.0 C1-naphthalenes 18.9 21.3 26.3 27.2 nd 15.4 21.4 C3-chrysenes/triphenylenes tr tr nd 2-methylnaphthalene 10.0 10.7 14.8 14.9 nd 6.4 12.1 C4-chrysenes/triphenylenes nd nd nd 1-methylnaphthalene 8.9 10.6 11.6 12.4 nd 9.0 9.4 benzo(k)fluoranthene 3.8 1.0 1.0 C2-naphthalenes 27.1 33.3 41.6 48.2 0.4 28.9 50.0 benzo(b)fluoranthene 7.6 4.5 8.0 2,6-dimethylnaphthalene 8.0 8.5 6.9 7.5 nd 5.6 16.0 benzo(e)pyrene 9.2 5.6 8.1 C3-naphthalenes 14.7 26.8 34.1 37.8 0.5 13.8 39.6 benzo(a)pyrene 3.8 1.6 1.6 2,3,5-trimethylnaphthalene nd 4.4 6.1 7.0 nd 2.4 3.8 9,10-diphenylanthracene nd nd nd C4-naphthalenes 1.7 12.0 17.9 19.8 nd 7.0 18.9 perylene 30.3 35.9 42.5 4biphenyl 5.6 4.3 9.2 9.9 nd 4.9 7.1 indeno(1,2,3-cd)pyrene nd nd nd acenaphthylene nd nd nd nd nd nd nd dibenz(a,h)anthracene nd nd nd acenaphthene nd 0.6 0.9 1.1 nd nd nd picene nd nd nd fluorene nd 2.9 4.9 5.1 nd 2.7 5.4 benzo(ghi)perylene nd 3.6 4.6 52-methylfluorene nd 2.7 4.3 5.1 nd nd nd anthanthrene nd nd nd C1-fluorenes 3.2 3.8 6.4 nd tr 2.8 5.8 coronene nd nd nd C2-fluorenes 4.9 6.7 13.3 nd tr 6.4 18.6 1,2,4,5-dibenzopyrene nd nd nd C3-fluorenes tr tr nd nd nd tr tr C1-C20H12 aromatics 9.5 5.1 6.9 phenanthrene 19.5 15.2 27.8 32.0 1.1 17.9 33.4 C2-C20H12 aromatics tr 1.7 2.6 1-methylphenanthrene 4.4 4.9 6.7 7.5 nd 3.4 8.8 C3-C20H12 aromatics nd tr nd anthracene 1.6 nd 1.3 1.3 nd nd nd C4-C20H12 aromatics nd tr nd C1-phenanthrenes/anthracenes 47.9 51.3 72.5 77.1 20.8 34.6 123.2C2-phenanthrenes/anthracenes 12.8 26.7 32.6 35.7 1.8 19.4 57.5 sum-naphthalenes(N) 70.1 100.9 132.9 143,6-dimethylphenanthrene nd 1.2 3.7 4.2 nd nd 1.8 sum-fluorenes(F) 8.1 13.4 24.6 C3-phenanthrenes/anthracenes 18.0 23.7 43.7 46.6 4.7 22.2 58.3 sum-phenanthrenes/anthracenes(PA) 105.1 127.9 194.8 21C4-phenanthrenes/anthracenes 5.2 10.9 17.0 17.5 1.0 9.5 28.0 sum-dibenzothiophenes(D) 11.0 35.2 23.3 22,3-benzofluorene nd 1.6 2.5 3.2 nd 1.3 2.9 sum-fluoranthenes/pyrenes(FP) 25.8 23.2 31.8 31,1 ́-binaphthalene nd nd nd nd nd nd nd sum-chrysenes(C) 22.5 21.5 33.3 3dibenzothiophene** nd 3.4 5.4 7.6 0.2 3.4 6.7 sum-C20H12 aromatics(C20) 64.2 55.2 70.6 7C1-dibenzothiophenes** 2.5 3.5 3.5 3.8 0.3 2.1 6.3 sum- 4,5 PAH (4,5 PAH) 107.0 94.6 128.9 13C2-dibenzothiophenes** 2.6 4.6 6.1 6.6 nd 2.9 12.0 sum-PAH(t-PAH) 316.4 388.8 531.3 55C3-dibenzothiophenes** 5.9 23.7 6.5 6.8 nd 1.8 6.8 N/PA 0.67 0.79 0.68 C4-dibenzothiophenes** nd tr 1.8 1.9 nd nd nd N/perylene 2.31 2.81 3.13 fluoranthene 3.8 2.7 4.1 4.3 nd 2.5 5.6 F/perylene 0.27 0.37 0.58 pyrene 5.7 4.9 7.6 8.6 0.6 4.4 9.6 PA/perylene 3.47 3.56 4.59 C1-fluoranthenes/pyrenes 3.8 4.2 6.8 7.1 tr 4.3 10.8 FP/perylene 0.85 0.65 0.75 C2-fluoranthenes/pyrenes 7.5 7.2 7.9 8.1 tr 7.2 12.8 t-PAH/perylene 10.45 10.83 12.51 1

49
Table 11. (cont.) 

Sample ID – UCLA No. 9 9B 10 11A 12 13 14 9 9B 10 1Surrogate Recovery (%) PAH (ng/g dry wt) (cont.) hexamethylbenzene 46 43 39 44 40 40 45 C3-fluoranthenes/pyrenes 1.6 2.9 1.3 n-dodecylbenzene 66 50 59 62 56 56 59 C4-fluoranthenes/pyrenes nd 3.2 1.1 4-terphenyl-D14 72 63 72 63 69 69 71 benz(a)anthracene 1.8 1.7 0.6 

chrysene/triphenylene 9.3 8.9 3.3 1

PAH (ng/g dry wt) C1-chrysenes/triphenylenes 6.7 6.8 2.4 1naphthalene 8.3 7.6 1.7 8.9 3.3 1.0 9.7 C2-chrysenes/triphenylenes 1.9 2.4 0.9 C1-naphthalenes 19.2 12.4 4.4 26.4 18.2 4.6 25.9 C3-chrysenes/triphenylenes nd nd nd 2-methylnaphthalene 9.7 7.0 2.5 13.8 9.3 2.7 14.8 C4-chrysenes/triphenylenes nd nd nd 1-methylnaphthalene 9.5 5.5 2.0 12.7 8.9 1.9 11.2 benzo(k)fluoranthene nd 0.6 0.3 C2-naphthalenes 23.3 19.5 7.8 42.7 46.9 9.4 46.7 benzo(b)fluoranthene 4.7 5.3 2.1 2,6-dimethylnaphthalene 7.3 6.2 2.0 14.4 12.9 2.5 12.1 benzo(e)pyrene 4.1 4.8 2.0 C3-naphthalenes 16.5 13.6 7.7 33.0 40.1 7.4 34.0 benzo(a)pyrene nd nd 0.4 2,3,5-trimethylnaphthalene 3.0 nd nd 3.1 4.2 0.9 4.1 9,10-diphenylanthracene nd nd nd C4-naphthalenes 7.0 6.5 2.6 13.1 16.1 4.6 18.4 perylene 15.6 79.8 13.7 3biphenyl 4.5 4.8 1.3 7.2 4.7 1.5 5.9 indeno(1,2,3-cd)pyrene nd nd nd acenaphthylene nd nd nd nd nd nd nd dibenz(a,h)anthracene nd nd nd acenaphthene nd nd nd nd nd nd nd picene nd nd nd fluorene 2.5 2.6 nd 4.3 4.0 1.1 4.0 benzo(ghi)perylene nd nd nd 2-methylfluorene nd nd nd nd 3.1 0.8 3.0 anthanthrene nd nd nd C1-fluorenes 3.5 3.1 1.2 5.3 5.5 1.2 6.3 coronene nd nd nd C2-fluorenes 6.0 5.6 2.6 15.0 13.1 1.9 13.1 1,2,4,5-dibenzopyrene nd nd nd C3-fluorenes tr tr tr tr tr tr tr C1-C20H12 aromatics 2.7 4.4 3.1 phenanthrene 14.9 17.3 5.3 24.0 25.1 6.4 21.3 C2-C20H12 aromatics nd 3.7 0.7 1-methylphenanthrene 3.1 5.1 1.6 6.7 8.0 1.9 6.5 C3-C20H12 aromatics nd nd nd anthracene nd nd nd nd nd nd nd C4-C20H12 aromatics nd nd nd C1-phenanthrenes/anthracenes 25.9 37.2 41.5 112.8 138.0 56.6 193.7C2-phenanthrenes/anthracenes 15.9 18.1 10.0 36.0 52.7 11.9 47.3 sum-naphthalenes(N) 74.3 59.5 24.2 123,6-dimethylphenanthrene 1.2 1.2 0.4 1.8 1.8 0.4 1.9 sum-fluorenes(F) 12.0 11.3 3.8 2C3-phenanthrenes/anthracenes 15.0 14.1 17.2 63.7 82.7 21.4 100.4 sum-phenanthrenes/anthracenes(PA) 81.5 94.5 79.4 25C4-phenanthrenes/anthracenes 6.3 7.8 5.4 20.3 18.6 6.4 22.9 sum-dibenzothiophenes(D) 16.8 6.3 4.4 12,3-benzofluorene 1.1 nd 0.3 2.1 2.6 nd 2.1 sum-fluoranthenes/pyrenes(FP) 15.5 24.6 9.1 21,1 ́-binaphthalene nd nd nd nd nd nd nd sum-chrysenes(C) 17.8 18.1 6.6 3dibenzothiophene** 3.5 3.3 1.0 5.0 nd 1.4 3.7 sum-C20H12 aromatics(C20) 27.1 98.6 22.3 5C1-dibenzothiophenes** 2.1 1.8 1.5 4.4 6.5 1.5 6.0 sum- 4,5 PAH (4,5 PAH) 59.6 134.8 34.8 10C2-dibenzothiophenes** 3.1 1.2 1.2 6.3 8.5 nd 4.1 sum-PAH(t-PAH) 252.6 319.4 152.0 55C3-dibenzothiophenes** 8.0 nd 0.7 4.2 8.4 nd 3.1 N/PA 0.91 0.63 0.30 C4-dibenzothiophenes** tr nd nd nd tr nd nd N/perylene 4.78 0.75 1.77 fluoranthene 3.2 2.4 0.9 4.1 5.1 1.2 3.7 F/perylene 0.77 0.14 0.28 pyrene 4.6 4.8 1.5 6.5 8.5 2.1 7.6 PA/perylene 5.24 1.18 5.80 C1-fluoranthenes/pyrenes 3.0 3.4 1.7 6.7 8.0 2.3 7.6 FP/perylene 1.00 0.31 0.66 C2-fluoranthenes/pyrenes 3.1 7.8 2.6 7.7 11.4 2.5 8.8 t-PAH/perylene 16.24 4.00 11.11 1

50
Table 11. (cont.) 

Sample ID – UCLA No. 15 16 17 18 19 20 OS# 15 16 17 1Surrogate Recovery (%) μg/g dry wt PAH (ng/g dry wt) (cont.) hexamethylbenzene 44 46 43.0 47 40 51 50 C3-fluoranthenes/pyrenes 1.5 nd tr n-dodecylbenzene 63 59 50.0 58 59 56 61 C4-fluoranthenes/pyrenes 2.0 nd nd 4-terphenyl-D14 70 68 69.0 63 68 69 70 benz(a)anthracene 0.8 4.8 0.1 

chrysene/triphenylene 6.8 10.2 0.3 

PAH (ng/g dry wt) C1-chrysenes/triphenylenes 6.1 6.6 0.1 1naphthalene nd 9.1 nd 9.6 1.3 0.5 2.9 C2-chrysenes/triphenylenes 2.5 nd nd C1-naphthalenes nd 11.9 0.1 24.2 2.7 1.0 nd C3-chrysenes/triphenylenes nd nd nd n2-methylnaphthalene nd 8.7 0.1 12.1 1.5 0.5 nd C4-chrysenes/triphenylenes nd nd nd n1-methylnaphthalene nd 3.3 nd 12.0 1.2 0.5 4.8 benzo(k)fluoranthene 0.8 nd nd C2-naphthalenes nd 20.9 0.3 34.6 4.5 1.9 83.0 benzo(b)fluoranthene 3.8 5.9 0.2 2,6-dimethylnaphthalene nd 7.5 nd 10.0 1.4 0.4 31.0 benzo(e)pyrene 4.5 nd 0.2 C3-naphthalenes 4.9 7.7 0.3 26.2 4.3 1.4 44.2 benzo(a)pyrene nd nd nd n2,3,5-trimethylnaphthalene nd nd nd 4.5 0.8 nd 7.4 9,10-diphenylanthracene nd nd nd nC4-naphthalenes 5.9 nd nd 13.2 2.1 0.6 15.0 perylene 19.2 29.2 nd 1biphenyl nd 4.8 0.1 5.4 0.8 0.3 nd indeno(1,2,3-cd)pyrene nd nd nd nacenaphthylene nd nd nd nd nd nd nd dibenz(a,h)anthracene nd nd nd nacenaphthene nd nd nd nd nd nd 0.5 picene nd nd nd nfluorene nd nd nd 3.3 0.7 nd 1.5 benzo(ghi)perylene nd nd nd 2-methylfluorene nd nd nd 2.7 0.4 nd 2.2 anthanthrene nd nd nd nC1-fluorenes 2.7 nd 0.3 3.9 0.9 0.8 2.0 coronene nd nd nd nC2-fluorenes 8.5 nd 0.4 10.6 3.7 1.6 2.1 1,2,4,5-dibenzopyrene nd nd nd nC3-fluorenes tr nd tr nd tr tr nd C1-C20H12 aromatics 4.2 tr 0.3 phenanthrene 10.3 17.1 1.0 18.3 3.6 1.9 2.3 C2-C20H12 aromatics nd tr nd n1-methylphenanthrene nd 3.7 nd 4.8 0.9 nd 1.1 C3-C20H12 aromatics nd nd nd nanthracene nd nd nd nd nd nd 0.7 C4-C20H12 aromatics nd nd nd nC1-phenanthrenes/anthracenes 86.7 25.3 15.0 124.1 24.2 109.3 3.8C2-phenanthrenes/anthracenes 25.8 13.6 1.4 36.5 6.5 10.6 4.4 sum-naphthalenes(N) 10.9 49.6 0.7 103,6-dimethylphenanthrene nd nd nd 1.8 0.2 nd 0.3 sum-fluorenes(F) 11.2 nd 0.7 1C3-phenanthrenes/anthracenes 64.0 6.8 7.2 61.9 21.9 57.4 5.7 sum-phenanthrenes/anthracenes(PA) 200.3 62.8 26.0 26C4-phenanthrenes/anthracenes 13.5 nd 1.4 24.3 5.9 6.2 2.1 sum-dibenzothiophenes(D) 12.8 nd 0.6 12,3-benzofluorene 1.4 nd nd 1.3 nd nd nd sum-fluoranthenes/pyrenes(FP) 18.5 8.0 0.9 21,1 ́-binaphthalene nd nd nd nd nd nd nd sum-chrysenes(C) 15.4 16.8 0.4 2dibenzothiophene** 2.2 nd 0.2 2.8 0.5 0.3 nd sum-C20H12 aromatics(C20) 32.5 35.2 0.7 3C1-dibenzothiophenes** 3.2 nd 0.3 3.5 0.7 0.6 0.4 sum- 4,5 PAH (4,5 PAH) 62.9 64.7 1.9 7C2-dibenzothiophenes** 3.2 nd 0.1 2.8 0.8 0.4 0.3 sum-PAH(t-PAH) 303.7 181.9 30.3 49C3-dibenzothiophenes** 4.3 nd tr 2.1 0.9 1.4 0.5 N/PA 0.05 0.79 0.03 C4-dibenzothiophenes** nd nd nd nd tr nd 0.5 N/perylene 0.57 1.70 na fluoranthene 2.4 2.6 0.2 3.2 1.8 0.7 2.5 F/perylene 0.58 nd na pyrene 4.3 4.5 0.3 4.9 2.0 0.8 2.0 PA/perylene 10.45 2.15 na 1C1-fluoranthenes/pyrenes 4.5 0.9 0.1 5.6 1.0 0.7 0.9 FP/perylene 0.96 0.27 na C2-fluoranthenes/pyrenes 3.7 nd 0.3 5.2 0.8 1.2 1.1 t-PAH/perylene 15.84 6.22 na 2

51
Table 11. (cont.) 

Sample ID – UCLA No. Pr. Blk X- SPIKE 1 X- SPIKE 2 X- SPIKE Avg Ref Sed SRM 1941† NIST Values† Sample ID – UCLA No. Pr. Blk X- SPIKE 1 X- SPIKE 2 

S

Surrogate Recovery (%) PAH (ng/g dry wt) (cont.) hexamethylbenzene 40 55 55 55 43 pyrene nd 78 86 n-dodecylbenzene 65 71 61 66 64 C1-fluoranthenes/pyrenes nd 4-terphenyl-D14 75 83 93 88 67 C2-fluoranthenes/pyrenes nd 

C3-fluoranthenes/pyrenes nd 

PAH (ng/g dry wt) C4-fluoranthenes/pyrenes nd naphthalene nd 34 30 32 1230 1322±14 benz(a)anthracene nd 59 63 C1-naphthalenes nd 43 chrysene/triphenylene nd 88 84 2-methylnaphthalene nd 44 40 42 336 406±36 C1-chrysenes/triphenylenes nd 1-methylnaphthalene nd 43 45 44 214 229±19 C2-chrysenes/triphenylenes nd C2-naphthalenes nd 49 C3-chrysenes/triphenylenes nd 2,6-dimethylnaphthalene nd 50 48 49 237 198±23 C4-chrysenes/triphenylenes nd C3-naphthalenes nd 57 benzo(k)fluoranthene nd 61 67 2,3,5-trimethylnaphthalene nd 59 55 57 87 96.3 benzo(b)fluoranthene nd 74 74 C4-naphthalenes nd 57 benzo(e)pyrene nd 68 60 biphenyl nd 57 65 61 104 115±15 benzo(a)pyrene nd 56 62 acenaphthylene nd 58 60 59 106 115±10 9,10-diphenylanthracene nd 77 74 acenaphthene nd 57 53 55 46 52±2 perylene nd 68 62 fluorene nd 57 59 58 88 104±5 indeno(1,2,3-cd)pyrene nd 63 64 2-methylfluorene nd 80 76 78 61 73.7 dibenz(a,h)anthracene nd 62 60 C1-fluorenes nd 78 picene nd 69 71 C2-fluorenes nd 75 benzo(ghi)perylene nd 62 66 C3-fluorenes nd 75 anthanthrene nd 52 56 phenanthrene nd 81 79 77 551 577±59 coronene nd 70 70 1-methylphenanthrene nd 80 76 78 92 109±6 1,2,4,5-dibenzopyrene nd 58 66 anthracene nd 78 78 78 171 202±42 C1-C20H12 aromatics nd C1-phenanthrenes/anthracenes nd 78 C2-C20H12 aromatics nd C2-phenanthrenes/anthracenes nd 75 C3-C20H12 aromatics nd 3,6-dimethylphenanthrene nd 79 71 75 56 78.0 C4-C20H12 aromatics nd C3-phenanthrenes/anthracenes nd 75 C4-phenanthrenes/anthracenes nd 75 2,3-benzofluorene nd 76 84 80 139 124.8 1,1 ́-binaphthalene nd 70 82 76 98 117.0 dibenzothiophene** nd 35 41 38 163 209.8 C1-dibenzothiophenes** nd 78 C2-dibenzothiophenes** nd 75 C3-dibenzothiophenes** nd 75 C4-dibenzothiophenes** nd 75 fluoranthene nd 80 88 84 1132 1220±240

* Duplicate analysis 

** Very low recovery due to activated copper treatment 

# OS=oil spill sample; note change in units of concen

nd=not detected, below MDLtr=trace amounts, not quantifiable na=not applicable 

% recovery of some methylated homologs assumed to b

methylated phenanthrenes

52
Table 12: Distribution (ng/g dry wt) of triterpenoids in gross sediments of Beaufort Lagoon. All 

sample numbers have the prefix BL03. O. is the oil spill sample. 

SAMPLE ID – UCLA No. 

Triterpanes (ng/g dry wt)* 1 2 3 4 5B 6B 9 9B 10 11A 

18α(H),21β(H)-22,29,30-trisnorhopane tr# tr tr tr tr 2 1 1 1 1 

17 α(H),21 β(H)-22,29,30-trisnorhopane 9 tr 6 tr tr 6 4 3 1 3 

17 β(H),21 β(H)-22,29,30-trisnorhopane 54 20 51 1 24 51 55 25 14 27 

17 α(H),18α(H),21 β(H)-28,30-bisnorhopane nd## nd nd nd nd nd nd nd nd nd 

17 α(H),21 β(H)-30-norhopane 16 10 20 1 11 22 18 11 2 13 

17 β(H),21α(H)-30-norhopane 32 12 30 1 15 32 28 15 8 17 

17 β(H),21 β(H)-30-norhopane** 138 37 111 2 61 125 128 39 33 39 

18 α(H)-oleanane nd nd nd nd nd nd nd nd nd nd 

17 α(H),21 β(H)-hopane 8 5 11 1 5 13 7 5 3 7 

17 β(H),21α(H)-hopane tr 9 nd tr 16 tr tr 27 tr nd 

17 β(H),21 β(H)-hopane 14 6 14 nd 7 14 12 6 3 8 

22S-17 α(H),21 β(H)-30-homohopane nd nd nd nd nd nd nd nd nd nd 

22R-17 α(H),21 β(H)-30-homohopane tr tr tr nd nd 15 tr nd nd nd 

17 β(H),21 β(H)-30-homohopane 10 3 13 tr 6 13 8 6 2 5 

22S-17 α(H),21 β(H)-30,31-bishomohopane nd nd nd nd nd nd nd nd nd nd 

22R-17 α(H),21 β(H)-30,31-bishomohopane nd nd tr nd nd nd nd nd nd nd 

22S-17 α(H),21 β(H)-30,31-trishomohopane nd nd nd nd nd nd nd nd nd nd 

22R-17 α(H),21 β(H)-30,31-trishomohopane nd nd nd nd nd nd nd nd nd nd 

22S-17 α(H),21 β(H)-30,31-tetrahomohopane nd nd nd nd nd nd nd nd nd nd 

22R-17 α(H),21 β(H)-30,31-tetrahomohopane nd nd nd nd nd nd nd nd nd nd 

hop-13(18)-ene 32 13 25 1 14 26 40 27 8 4 

hop-21(22)-ene nd nd nd nd nd nd nd nd nd nd 

diploptene 260 112 182 3 148 254 181 173 93 116 

SAMPLE ID – UCLA No. 

Triterpanes (ng/g dry wt)* 12 13 14 15 16 17 18 19 20 

OS

 μg/g

dry wt

18α(H),21β(H)-22,29,30-trisnorhopane 1 3 1 3 nd nd 1 1 nd 56 

17 α(H),21 β(H)-22,29,30-trisnorhopane 6 8 5 4 13 nd 5 2 1 57 

17 β(H),21 β(H)-22,29,30-trisnorhopane 44 32 36 16 202 nd 46 18 7 nd 

17 α(H),18α(H),21 β(H)-28,30-bisnorhopane nd nd nd nd nd nd nd nd nd nd 

17 α(H),21 β(H)-30-norhopane 24 23 23 15 57 1 19 8 2 315 

17 β(H),21α(H)-30-norhopane 24 17 18 11 118 1 26 11 5 30 

17 β(H),21 β(H)-30-norhopane** 87 70 83 29 398 1 107 45 13 56 

18 α(H)-oleanane nd nd nd nd nd nd nd nd nd nd 

17 α(H),21 β(H)-hopane 11 16 9 9 18 nd 8 3 1 263 

17 β(H),21α(H)-hopane tr nd nd 12 nd nd nd nd nd nd 

17 β(H),21 β(H)-hopane 13 11 10 2 44 nd 13 4 2 nd 

22S-17 α(H),21 β(H)-30-homohopane nd nd nd nd nd nd nd nd nd 103 

22R-17 α(H),21 β(H)-30-homohopane nd 6 nd nd nd nd nd 1 nd 68 

17 β(H),21 β(H)-30-homohopane 11 6 9 3 11 nd 11 3 2 nd 

22S-17 α(H),21 β(H)-30,31-bishomohopane nd nd nd nd nd nd nd nd nd 44 

22R-17 α(H),21 β(H)-30,31-bishomohopane nd nd nd nd nd nd nd nd nd 31 

22S-17 α(H),21 β(H)-30,31-trishomohopane nd nd nd nd nd nd nd nd nd 27 

22R-17 α(H),21 β(H)-30,31-trishomohopane nd nd nd nd nd nd nd nd nd 7 

22S-17 α(H),21 β(H)-30,31-tetrahomohopane nd nd nd nd nd nd nd nd nd 7 

22R-17 α(H),21 β(H)-30,31-tetrahomohopane nd nd nd nd nd nd nd nd nd Tr 

hop-13(18)-ene 32 30 18 15 53 nd 21 9 2 ? 

hop-21(22)-ene nd nd nd nd nd nd nd nd nd nd 

diploptene 352 211 314 143 903 1 184 64 28 nd 

* Quantification based on m/z 191; also note change in the units for OS sample 

** May be coeluting with C30 βαhopane in some samples # Trace amounts, not quantifiable ## Not detected, below detection limits 

53
Table 13: Distribution (ng/g dry wt) of steroids in gross sediments of Beaufort Lagoon. All sample 

numbers have the prefix BL03. OS is the oil spill sample. 

SAMPLE ID – UCLA No. 

Steranes (ng/g dry wt)* 1 2 3 4 5B 6B 9 9B 10 11A 

5α(H)androstane nd## nd nd nd nd nd nd nd nd nd 

5α(H)pregnane nd nd 1.4 0.1 nd nd nd nd nd nd 

5β(H)pregnane nd 0.7 1.6 0.1 0.7 2.8 1.1 nd nd nd 

20-methyl-5α(H)pregnane nd nd nd 0.2 0.4 1.0 nd nd nd nd 

20S-13β(H),17α(H)-diacholestane** S1# nd nd nd 0.3 0.8 3.7 1.0 0.9 nd 1.3 

20R-13β(H),17α(H)-diacholestane S2 nd nd nd 0.2 0.7 2.3 0.7 0.9 nd nd 

20S-5α(H),14α(H),17α(H)-cholestane S3 nd nd nd 0.2 0.8 2.6 1.1 1.0 nd 1.2 

20R-5α(H),14α(H),17α(H)-cholestane S6 nd nd nd 0.2 0.8 2.6 0.8 nd nd nd 

20R-5α(H),14β(H),17β(H)-cholestane S4 nd nd nd 0.4 2.8 6.7 1.8 nd nd nd 

20S-5α(H),14β(H),17β(H)-cholestane S5 nd nd nd 0.2 1.5 5.2 nd nd nd 3.3 

20R-24-ethyl-13β(H),17α(H)-diacholestane S7 nd nd nd 0.2 1.2 3.2 1.8 nd nd nd 

20S-5α(H),14α(H),17α(H)-ergostane S8 nd nd nd nd nd nd nd nd 1.3 nd 

20R-5α(H),14α(H),17α(H)-ergostane S11 nd nd nd 0.2 nd nd 2.5 nd nd nd 

20R-5α(H),14β(H),17β(H)-ergostane S9 nd nd nd nd nd nd nd nd nd nd 

20S-5α(H),14β(H),17β(H)-ergostane S10 nd nd nd 0.2 nd nd nd nd nd nd 

20S-5α(H),14α(H),17α(H)-stigmastane S12 nd nd nd 0.2 nd nd nd nd nd nd 

20R-5α(H),14α(H),17α(H)-stigmastane S15 7.5 6.9 5.4 0.1 3.1 3.2 1.6 1.4 2.0 1.1 

20R-5α(H),14β(H),17β(H)-stigmastane S13 nd nd nd 0.3 0.8 2.3 1.5 nd 1.1 nd 

20S-5α(H),14β(H),17β(H)-stigmastane S14 nd nd nd nd nd nd nd nd nd nd 

SAMPLE ID – UCLA No. 

Steranes (ng/g dry wt)* 12 13 14 15 16 17 18 19 20 

OS

 μg/g

dry wt

5α(H)androstane nd nd nd nd nd nd nd nd nd 8 

5α(H)pregnane nd 1.5 0.8 nd nd nd nd nd nd 8 

5β(H)pregnane 1.4 4.2 1.9 2.1 nd 0.1 nd 0.7 nd 11 

20-methyl-5α(H)pregnane 0.9 1.7 1.4 nd nd 0.1 0.8 nd nd 4 

20S-13β(H),17α(H)-diacholestane** S1# 1.7 4.4 2.0 3.1 nd 0.1 1.7 0.9 0.5 116 

20R-13β(H),17α(H)-diacholestane S2 1.8 2.6 1.3 1.8 nd nd 1.0 0.6 0.2 92 

20S-5α(H),14α(H),17α(H)-cholestane S3 1.3 1.9 2.4 2.3 nd 0.1 1.5 0.8 nd 64 

20R-5α(H),14α(H),17α(H)-cholestane S6 1.7 2.9 1.7 nd nd nd 0.9 0.5 0.2 55 

20R-5α(H),14β(H),17β(H)-cholestane S4 4.2 6.6 3.4 nd nd nd 2.1 1.1 0.6 215 

20S-5α(H),14β(H),17β(H)-cholestane S5 2.3 3.9 1.8 nd nd nd 2.3 1.3 0.3 125 

20R-24-ethyl-13β(H),17α(H)-diacholestane S7 1.0 5.0 1.5 nd nd nd 1.1 0.5 0.2 170 

20S-5α(H),14α(H),17α(H)-ergostane S8 nd 5.2 nd nd nd nd nd nd nd 37 

20R-5α(H),14α(H),17α(H)-ergostane S11 nd 7.5 1.3 nd nd nd 2.3 nd nd 126 

20R-5α(H),14β(H),17β(H)-ergostane S9 5.5 4.3 nd nd nd nd 1.9 nd nd 217 

20S-5α(H),14β(H),17β(H)-ergostane S10 nd 7.2 5.5 nd nd nd nd nd nd 63 

20S-5α(H),14α(H),17α(H)-stigmastane S12 nd 1.0 1.5 nd nd nd nd nd nd 69 

20R-5α(H),14α(H),17α(H)-stigmastane S15 3.7 5.4 13.0 8.7 38.2 0.1 2.1 1.4 1.2 26 

20R-5α(H),14β(H),17β(H)-stigmastane S13 3.2 3.0 2.4 nd nd nd 2.0 0.7 nd 141 

20S-5α(H),14β(H),17β(H)-stigmastane S14 nd nd nd nd nd nd nd nd nd 55 

* Note change in the units for OS sample 

** Steranes of similar configuration assumed to have the same RF as in the standard compounds mixture # Notation to be used in figures ## Not detected, below detection limits 

54
55

Table 14: Component loadings for the first two PCs. 

Table 15: Correlations between PC 1 and PC 2 with latitude, longitude, silt and organic carbon. 

Parameter PC 1 (p-value) PC 2 (p-value) 

Latitude -0.544 (0.0160) -0.304 (0.2058) 

Longitude 0.021 (0.9324) 0.328 (0.1709) 

Silt -0.274 (0.2572) 0.758 (0.0002) 

OC 0.547 (0.0153) -0.242 (0.3173) 

Table 16: Correlations between PC 1 and PC 2 with latitude, longitude, silt and organic carbon 

(excluding outliers BL03-4 and BL03-17). 

Parameter PC 1 (p-value) PC (p-value) 

Latitude -0.428 (0.0862) -0.473 (0.0551) 

Longitude 0.147 (0.5742) 0.604 (0.0102) 

Silt -0.726 (0.0010) 0.516 (0.0339) 

OC 0.516 (0.0341) -0.390 (0.1218) 

Table 17: Analysis of Variance for the Response of PC 1. 

Df Sum of Sq Mean Sq F Value Pr (F) 

Silt 1 39.30097 39.30097 26.30329 0.000153386

Latitude 1 14.34431 14.34431 9.60034 0.007856686

residuals 14 20.91805 1.49415 

Metal Comp.1 Comp.2 

V 0.338 0.120 

Cr 0.311 0.131 

Mn 0.116 -0.473 

Ni 0.343 -0.106 

Cu 0.335 0.010 

Zn 0.316 0.260 

As 0.269 0.074 

Cd 0.242 -0.232 

Sn 0.264 -0.387 

Ba 0.162 0.434 

Pb 0.338 -0.162 

Fe 0.323 0.143 
Table 18: Comparison of the mean concentrations of selected trace metals in Beaufort Lagoon mud with ERL and ERM gu

percent incidence of biological effects in concentration ranges defined by two values as reported by Long et al. (1995). 

THIS STUDY DATA FROM LONG ET AL. [1995]

Guidelines Percent (ratios) incidence of effe

Beaufort Lagoon ERL ERM

ppm dry wt ppm dry wt

< ERL ERL‐ERM 

As 14 8.2 70 5.0 (2/40) 11.1 (8/73) 

Cd 0 1.2 9.6 6.6 (7/106) 36.6 (32/87) 

Cr 73 81 370 2.9 (3/102) 21.1 (15/71) 

Cu 36 34 270 9.4 (6/64) 29.1 (32/110) 

Pb 17 46.7 218 8.0 (7/87) 35.8 (29/81) 

Ni 39 20.9 51.6 1.9 (1/54) 16.7 (8/48) 

Zn 92 150 410 6.1 (6/99) 47.0 (31/66) 

THg 0.04 0.15 0.71 8.3 (4/48) 23.5 (16/68) 

56

* Number of data entries within each concentration range in which biological effects were observed divided by th

entries within each range. 
Table 19: Comparison of the mean concentrations of selected hydrocarbons in Beaufort Lagoon gross sediments with ERL 

values, and percent incidence of biological effects in concentration ranges defined by two values as reported by Long et al. 

THIS STUDY DATA FROM LONG ET AL. [1995]

Guidelines Percent (ratios) incidence of effe

Beaufort Lagoon ERL ERM

ng g‐1 dry wt ppb dry wt

< ERL ERL‐ERM 

naphthalene 6.00 160 2100 16.0 (4/25) 41.0 (16/39) 8

2‐methylnaphthalene 12.40 70 670 12.5 (2/16) 73.3 (11/15) 1

acenaphthylene nd 44 640 14.3 (1/7) 17.9 (5/28) 

acenaphthene nd 16 500 20.0 (3/15) 32.4 (11/34) 8

fluorene 2.18 19 540 27.3 (3/11) 36.5 (19/52) 8

phenanthrene 15.67 240 1500 18.5 (5/27) 46.2 (18/39) 9

anthracene 0.21 85.3 1100 25.0 (4/16) 44.2 (19/43) 8

fluoranthene 2.73 600 5100 20.6 (7/34) 63.6 (28/44) 9

pyrene 4.69 665 2600 17.2 (5/29) 53.1 (17/32) 

benz(a)anthracene 1.80 261 1600 21.1 (4/19) 43.8 (14/32) 

chrysene/triphenylene# 8.91 384 2800 19.0 (4/21) 45.0 (18/40) 

benzo(a)pyrene 0.63 430 1600 10.3 (3/29) 63.0 (17/27) 

dibenz(a,h)anthracene nd, below MDL 63.4 260 11.5 (3/26) 54.5 (12/22) 

Sum PAH 314.44 4022 44792 14.3 (3/21) 36.1 (13/36) 

57

* Number of data entries within each concentration range in which biological effects were observed divided by t

of entries within each range

# Reported as chrysene in the Long et al. study.