Characterization of sediment contaminants in Arctic lagoons and estuaries.

Baseline characterizations of estuarine sediments in Chukchi and Beaufort Seas, were conducted. Concentrations of 194 organic and elemental chemicals were analyzed in sediment and fish, plus stable isotopes of carbon and nitrogen. The estuaries are shallow embayments, with little shoreline relief. The water columns were turbid, high salinity, and not stratified. Concentrations of arsenic and nickel were elevated throughout the region. Arsenic in fish tissue was elevated. Concentrations of PAHs were relatively high for pristine locations, but did not include petroleum hydrocarbons. Characteristics of PAHs indicate large contributions of terrestrial organic matter. With the exception of Peard Bay, all the estuaries reflected the strong influence of terrestrial plant input with low δo/oo values for carbon and nitrogen. Chlorinated pesticides and PCBs were uniformly low, but detectable in fish tissue. PCB and cyclodiene concentrations were half that seen in southeast Bristol Bay. Hexachlorobenzene was detected in all fish samples.

Characterization of organic contaminants in fjords and bays on the Kenai Peninsula Alaska.

A baseline environmental characterization of Seldovia Bay and harbor on the Kenai Peninsula, Alaska, was conducted using a sediment quality approach. The data was derived from a larger study that assessed seven distinct water bodies on the Kenai Peninsula's north side, draining into Kachemak Bay or into Lower Cook Inlet. Sampling sites for water quality measurements, sediment chemistry, and benthos were randomized within each embayment. Concentrations of 140 organic and elemental contaminants were analyzed. Habitat parameters (depth, salinity, grain size, organic carbon, etc.) that influence species and contaminant distribution were also measured at each sampling site. Concentrations of chlorinated pesticides and PCBs were uniformly low, with the exception of Seldovia Harbor, where total DDT and PCBs exceeded the lower sediment quality guidelines. Concentrations of PAHs were relatively low, except in Seldovia Harbor where concentrations exceeded lower sediment quality guidelines for PAHs, and in one location approached the upper limit. That concentration of PAHs exceeded all other measurements in the NOAA National Status & Trends database for the entire State of Alaska. Characteristics of the PAH compounds present indicate large contributions of pyrogenic sources (burned fuel and/or other organic matter). Seldovia Bay had much lower PAH concentrations than the harbor.

Shaping femtosecond laser pulses at short wavelength with grazing-incidence optics.

We present the design of an extreme ultraviolet (XUV) pulse shaper relying on reflective optics. The instrument will allow tailoring of the time-frequency spectrum of femtosecond pulses generated by seeded free-electron lasers (FEL) and high-harmonic generation (HHG) sources down to a central wavelength of ~15 nm. The device is based on the geometry of a 4f grating compressor that is a standard concept in ultrafast laser science and technology. We apply it to shorter wavelengths using grazing-incidence optics operated under ultra-high vacuum conditions. The design blaze angle and the line density of the gratings allow the manipulation of all different harmonics typical for seeded FEL and HHG photon sources without the need of realignment of the instrument and even simultaneously in multi-color experiments. A proof-of-principle pulse shaping experiment using 266 nm laser light has been performed, demonstrating relative phase-control of femtosecond UV pulses.

Characterization of metal/metalloid concentrations in fjords and bays on the Kenai Peninsula, Alaska.

A baseline environmental characterization of Chrome and Dogfish bays on the Kenai Peninsula, Alaska, was conducted using a sediment quality triad approach. Resident fish and blue mussel body burdens were also assessed. The data was derived from a larger study that assessed seven distinct water bodies on the Kenai Peninsula's north side, draining into Kachemak Bay. Sampling sites for water quality measurements and sediment were randomized within each embayment. Concentrations of 140 organic and elemental contaminants were analyzed. Habitat parameters (depth, salinity, temperature, dissolved oxygen, sediment grain size, and organic carbon content) that influence elemental distribution were also measured at each sampling site. Chrome Bay and Dogfish Bay open into lower Cook Inlet and had coarser sediments than the other bays studied. Concentrations of chromium and nickel were extremely high in Chrome Bay. Concentrations were several times higher than observed concentrations seen throughout other locations in south-central Alaska. Other elemental concentrations varied between and within bays, with several locations exceeding lower sediment quality guidelines. Whole sediment amphipod toxicity bioassays were conducted with sediments from Chrome Bay. No sample exhibited significant mortality or sublethal effects. Body burdens of three species of fish and mussels collected in Chrome Bay did not exhibit elevated concentrations relative to other studies in Kachemak Bay or the Alaska Dept. of Environmental Conservation, Fish Monitoring Program. Despite the very high concentrations of Cr and Ni in the sediments, the metals do not appear to be bioavailable to resident biota.

An assessment of nutrients and sedimentation in the St. Thomas East End Reserves, US Virgin Islands.

Nutrients and sedimentation were monitored for approximately 2 years at six sites in the St. Thomas East End Reserves (STEER), St. Thomas, USVI, as part of a NOAA project to develop an integrated environmental assessment. Concentrations of ammonium (NH4+) and dissolved inorganic nitrogen (DIN) were higher in Mangrove Lagoon and Benner Bay in the western portion of STEER than in the other sites further east (i.e., Cowpet Bay, Rotto Cay, St. James, and Little St. James). There was no correlation between rainfall and nutrient concentrations. Using a set of suggested nutrient thresholds that have been developed to indicate the potential for the overgrowth of algae on reefs, approximately 60% of the samples collected in STEER were above the threshold for orthophosphate (HPO4=), while 55% of samples were above the DIN threshold. Benner Bay had the highest sedimentation rate of any site monitored in STEER, including Mangrove Lagoon. There was also an east to west and a north to south gradient in sedimentation, indicative of higher sedimentation rates in the western, more populated areas surrounding STEER, and sites closer to the shore of the main island of St. Thomas. Although none of the sites had a mean or average sedimentation rate above a suggested sedimentation threshold, the mean sedimentation rate in Benner Bay was just below the threshold.

An assessment of butyltins and metals in sediment cores from the St. Thomas East End Reserves, USVI.

Tributyltin (TBT) concentrations near a marina complex in Benner Bay on St. Thomas, US Virgin Islands, were elevated relative to other areas in a larger study of the southeastern shore of the island. At the request of the USVI Coastal Zone Management Program, sediment cores and surface sediment samples were collected to better define the extent and history of TBT deposition in the vicinity of Benner Bay. The sediment cores were sectioned into 2-cm intervals and dated with 210Pb and 137Cs. The core sections and the surface samples were analyzed for butyltins and 16 elements. Deposition rates varied from 0.07-5.0 mm/year, and were highest in the marina complex. Core ages ranged from 54 to 200 years. The bottoms of the cores contained shell hash, but the top layers all consisted of much finer material. Surface concentrations of TBT exceeded 2000 ng Sn/g (dry weight) at two locations. At a depth of 8 cm TBT exceeded 8800 ng Sn/g in the marina complex sediment. Based on the ratio of tributyltin to total butyltins, it appears that the marina sediments are the source of contamination of the surrounding area. There is evidence that vessels from neighboring islands may also be a source of fresh TBT. Copper concentrations increase over time up to the present. Gradients of virtually all metals and metalloids extended away from the marina complex. NOAA sediment quality guidelines were exceeded for As, Pb, Cu, Zn, and Hg.

Chemical contaminants in surficial sediment in Coral and Fish Bays, St. John, U.S. Virgin Islands.

Land based sources of pollution have the potential to negatively impact coral reef ecosystems. Many coral systems, including environmentally sensitive marine protected areas, do not have assessments of their chemical contaminant status (magnitude and extent). Without a status assessment, it is impossible to measure change in a system. This study presents surficial sediment data from Coral and Fish Bays (St. John, US Virgin Islands (USVI)). Portions of these bays are included in Virgin Islands National Park, and Virgin Islands Coral Reef National Monument. A suite of analytes (PCBs, PAHs, pesticides, heavy metals, butyltins) was quantified and compared against other regional data and against previously published sediment quality guidelines (SQG). Contamination from toxic contaminants in the system was generally low when compared to other similar studies and potential toxicity thresholds (SQG). Exceptions to this were copper and total chlordane which exceeded the Effects Range Low (ERL) sediment quality guideline, indicating possible sediment toxicity. This assessment will be useful to coastal managers for tracking environmental change, and ensuring that this marine protected area remains relatively free from toxic contamination.

An assessment of chemical contaminants in sediments from the St. Thomas East End Reserves, St. Thomas, USVI.

The St. Thomas East End Reserves or STEER is located on the southeastern end of the island of St. Thomas, USVI. The STEER contains extensive mangroves and seagrass beds, along with coral reefs, lagoons, and cays. Within the watershed, however, are a large active landfill, numerous marinas, resorts, various commercial activities, an EPA Superfund Site, and residential areas, all of which have the potential to contribute pollutants to the STEER. As part of a project to develop an integrated assessment for the STEER, 185 chemical contaminants were analyzed in sediments from 24 sites. Higher levels of chemical contaminants were found in Mangrove Lagoon and Benner Bay in the western portion of the study area. The concentrations of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), zinc, copper, lead, and mercury were above a NOAA Effects Range-Low (ERL) sediment quality guideline at one or more sites, indicating impacts may be present in more sensitive species or life stages. Copper at one site in Benner Bay was above a NOAA Effects Range-Median (ERM) guideline indicating effects on benthic organisms were likely. The antifoulant boat hull ingredient tributyltin (TBT) was found at the third highest concentration in the history of NOAA's National Status and Trends (NS&T) Program, which monitors the nation's coastal and estuarine waters for chemical contaminants and bioeffects. The results from this project will provide resource managers with key information needed to make effective decisions affecting coral reef ecosystem health and gauge the efficacy of restoration activities.

Chesapeake Bay watershed pesticide use declines but toxicity increases.

Large areas of the Chesapeake Bay, USA, watershed are in agricultural land use, but there is no baywide program to track application rates of current-use pesticides in any of the watershed jurisdictions. Watershed studies demonstrate that several pesticides are present in surface and groundwater throughout the region. Between 1985 and 2004, the Maryland Department of Agriculture conducted surveys to estimate pesticide application within the state. Application rates of the dominant insecticides and herbicides were compiled over the survey period. Toxicity of the pesticides was tabulated, and the toxic units (TU) of applied active ingredients were calculated for several animal and plant species. The total mass of pesticides being applied to the watershed declined during the survey period. Due to increasing potency of the chemicals, however, total TUs applied have remained static or have significantly increased depending on the species of bioassay test organism used to assess toxicity. Applying estimates of pesticide transport into rivers in the Mississippi River basin show that significant quantities of pesticides may be entering Chesapeake Bay.

Empirical assessment of incorporating sediment quality triad data into a single index to distinguish dominant stressors between sites.

Benthic infaunal community structure, sediment contamination, and sediment toxicity data (Sediment Quality Triad) were condensed into a single index based on the area of tri-axial plots, which were examined in relation to various habitat parameters. The purpose was to assess its utility for evaluating the relative impact of contaminants versus other stressors on benthic communities. The regression relationship between the areal index and the Effects Range-Median quotient (ERMq) was used to separate contaminant-impacted sites from sites impacted by hypoxia in Chesapeake Bay. Regression using the areal index and bottom oxygen confirm the utility of the approach. Data from Delaware, Galveston, and Biscayne Bays were also examined to determine if the approach may be effective in other estuaries.

Simple lab-on-chip approach with time-based detection.

A simple lab-on-chip approach with time-based detection is proposed. A platform is made from a piece of acrylic differently shaped channels for introducing sample and reagent(s) using flow manipulation. Time-based changes involving migration of the reaction zone are monitored. The changes can be visually monitored by using a stop-watch with naked eyes observation. Some applications for the determination of ascorbic acid, acetic acid and iron in real samples with different chemistries were demonstrated.

Distribution of DDT and other persistent organic contaminants in Canyons and on the continental shelf off the central California coast.

Sediment samples were collected to delineate the distribution of contaminants along the central California coast. Sampling included a variety of Canyons and shelf/slope areas to evaluate contaminant transport patterns and potential delivery to Canyons and the continental slope to a depth of 1200 m. Sediments were collected and analyzed for organic contaminants using standard techniques of the NOAA National Status and Trends Program (NS&T). DDT is distributed on the shelf within a zone of fine-grained sediments between Half Moon and Monterey Bays. DDT was found at higher concentrations in Ascension, Año Nuevo, and Monterey/Soquel Canyons than in Pioneer and Carmel Canyons, the Gulf of the Farallones, or the continental slope. The Monterey Bay watershed appears to be the primary source of DDT. In contrast, PAHs and PCBs on the shelf appear to be derived primarily from San Francisco Bay. DDT appears to be delivered to the deep ocean via the Canyons more than from cross-shelf sediment transport. Sediment budget estimates for the continental shelf north of Monterey Bay need further refinement and more data to account for the movement of material from Monterey Bay onto the shelf.

Habitat conditions and correlations of sediment quality triad indicators in Delaware Bay.

This paper summarizes sampling results from NOAA's National Status and Trends (NS&T) Program for marine environmental quality in Delaware Bay. A stratified-random design was used to determine the spatial extent of sediment contamination and toxicity in Delaware Bay from offshore stations in the coastal zone, the lower estuary, the upper estuary, the fresh/salt mixing zone, and tidal fresh areas. Sediment samples were taken for chemical analyses of major classes of environmental contaminants, a suite of toxicity bioassays, and benthic macrofaunal community assessment to identify patterns of resident species. The tidal-fresh areas and portions of the mixing zone of the study area were heavily contaminated. Contaminant concentrations were frequently above the 90th percentile of EMAP Virginian Province levels. PAHs in the sediment were higher than previously documented, with a major component of PAHs being pyrogenic in origin. Bioassay results were highly variable. Toxicity and contaminant levels were correlated when aggregated into indices, but were only marginally correlated with benthic community impacts. High and low abundance stations were found in all zones. Most of the tidal fresh stations were dominated by pollution tolerant species. Species diversity and abundance were generally lowest in the fresh/salt mixing zone.

Cluster analysis of contaminated sediment data: nodal analysis.

The objective of the present study was to explore the use of multivariate statistical methods as a means to discern relationships between contaminants and biological and/or toxicological effects in a representative data set from the National Status and Trends (NS&T) Program. Data from the National Oceanic and Atmospheric Administration, NS&T Program's Bioeffects Survey of Delaware Bay, USA, were examined using various univariate and multivariate statistical techniques, including cluster analysis. Each approach identified consistent patterns and relationships between the three types of triad data. The analyses also identified factors that bias the interpretation of the data, primarily the presence of rare and unique species and the dependence of species distributions on physical parameters. Sites and species were clustered with the unweighted pair-group method using arithmetic averages clustering with the Jaccard coefficient that clustered species and sites into mutually consistent groupings. Pearson product moment correlation coefficients, normalized for salinity, also were clustered. The most informative analysis, termed nodal analysis, was the intersection of species cluster analysis with site cluster analysis. This technique produced a visual representation of species association patterns among site clusters. Site characteristics, such as salinity and grain size, not contaminant concentrations, appeared to be the primary factors determining species distributions. This suggests the sediment-quality triad needs to use physical parameters as a distinct leg from chemical concentrations to improve sediment-quality assessments in large bodies of water. Because the Delaware Bay system has confounded gradients of contaminants and physical parameters, analyses were repeated with data from northern Chesapeake Bay, USA, with similar results.

High-resolution method for regulatory control of Echinacea species in Nutraceuticals by CD-MEKC.

One problem in the international regulatory control of Echinacea, a therapeutic Nutraceutical, is recognition of caffeoyl solutes and alkamides in different products. Cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC) has been applied to Echinacea spp. in combination with pattern recognition of some caffeoyl solutes. A novel metric based on relative migration time (RMT) data has been developed in CE to address the problem of variable reported migration time. The CD-MEKC method of Gotti's group using hydroxypropyl-beta-cyclodexrin (HP-beta-CD; 100 mM) with sodium dodecyl sulphate (SDS; 110 mM), in a triacid background electrolyte (10 mM, pH 8) under 19 kV was adapted to identify two key hydrophilic solutes: chlorogenic acid and cichoric acid present in all commercial products. Two internal markers were taken as reference points to calculate the RMT of any target peak: RMT=t(m (target))/t(m (marker)). The RMT method was robust to temperature change from 20 to 40 degrees C, but sensitive to pH. The lateral shift and reproducibility of the target peak t(m (target)) were significantly reduced by this novel transformation. In the worst cases migration time variability ranged up to 12% (n=6); the RMT algorithm reduced this to less than 1%. In general, the RMT transformation reduced the variability of migration time data by a factor of 2-5. For systematic comparison of electrophoretic profiles for test sample and standard, a new pattern recognition algorithm permits sequential peak-by-peak comparison using specified segments of the electropherograms for comparison of test and Echinacea purpurea (root product) as a standard. This algorithm was capable of rapidly characterising the similarity of target peaks in a test sample relative to those in the reference standard. Combination of the RMT algorithm and pattern recognition in CE is expected to offer a robust approach to international regulatory characterisation and control of Nutraceuticals.

Regional comparisons of coastal sediment contamination detected by a biomarker (P450 HRGS; EPA Method 4425).

Pollution investigations by the Center for Coastal Monitoring and Assessment of the National Oceanic and Atmospheric Administration (NOAA) have been conducted since 1984 and have incorporated extensive biological and chemical analyses. Since 1993, one of the biological tests utilized in these studies has been the biomarker P450HRGS, which is more recently described as EPA Method 4425. Extracts of sediments are applied to a human cell line with a reporter gene (firefly luciferase) at the CYP1A1 site. Light produced by the extracts is a function of the concentrations and potencies of those compounds with an affinity for Ah-receptor (certain polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and dioxins/ furans). These compounds are carcinogenic and can produce chronic toxicity, and those containing chlorine are persistent and bioaccumulated. Nineteen coastal regions and 1309 samples from the three U.S. coasts have been evaluated as part of the NOAA investigations. The stratified random sampling approach used by NOAA provides estimates of the areas (km2) of each region containing levels of the compounds above thresholds. From analysis of the database, sediments with concentrations at or below 11 microg benzo[a]pyrene equivalents (B[a]PEq)/g would not be expected to produce effects on the benthos. At 32 microg B[a]PEq/g and above there is the potential for impacts on the biota, and above 60 microg/g, the degradation of the benthic community has been observed. Several of the regional surveys found no samples at or above 60 microg B[a]PEq/g, but 60% of the samples from New York Harbor (280 km2) were above this level. Analyses of data from Puget Sound and Chesapeake Bay demonstrate an increase in samples above 32 microg B[a]PEq/g in more populated and industrial regions. Method 4425 serves as both a biomarker, simulating the response of an organism (with CYP1A) exposed to inducing compounds, and as a bioanalytical technique measuring the levels of these chemicals in the samples. A targeted investigation of the distribution of the three important classes of compounds identified by Method 4425 would be more cost-effective by first screening samples by this method before expending substantial funds in the detailed chemical analysis of all samples.

Distribution of DDT in sediments off the central California coast.

A collaborative sampling cruise off the central California coast was conducted to evaluate contaminant transport pathways along and across the shelf in the spring of 2002. The area has a complex current structure and net transport routes are not known for sure. Sediment characteristics, and organic and trace metal contaminants were analyzed in sediments taken from locations near shore, out to the heads of several canyons. Relative to the continental shelf and Pioneer Canyon stations, DDT was found at higher concentrations in Ascension and Monterey Canyons. Monterey Bay still receives DDT from terrestrial runoff and may be the source of DDT found in Ascension Canyon. DDT concentrations in Monterey Bay biota indicate bioaccumulation is occurring at depth due to continuing input from the shore. Effects on the deep ocean benthic community is unknown.

A simple flow injection system with bead injection for trace iron determination.

A simple and low cost flow injection (FI) system with bead injection (BI) was developed for determination of low concentration (mumol l(-1)) of iron in water samples. Chelex-100 chelating resin beads, trapped in a jet ring cell, were employed. The intensity of red complex of 1,10-phenanthroline with Fe(2+) was monitored using colorimetric detector with a LED green light source. Amount of total Fe (Fe(2+) and Fe(3+)) and Fe(2+) can be evaluated by with and without reduction of Fe(3+) using ascorbic acid. Lowest detectable levels of Fe(2+) were 0.90 and 0.45 mumol l(-1) for sample loading time of 3 and 5 min, respectively. Working range was up to 3.90 mumol l(-1) using 0.3% w/v 1, 10-phenanthroline. Percent recoveries of spiked water samples (0.90-2.33 mumol l(-1) of Fe(2+)) were 100-110%.

Determination of trace iron in beer using flow injection systems with in-valve column and bead injection.

Three flow injection (FI) systems were investigated for the determination of trace iron in beer: an FI-in-valve column-flame atomic absorption spectrophotometry (FI-FAAS) system, a spectrophotometric FI system with a column placed at the detection point, and an FI-spectrophotometric system with bead injection (FI-BI). Cationic exchange resin Dowex 50W X8 and iminodiacetate chelating resin, Chelex-100, were employed for the FI-spectrophotometric and FI-FAAS systems, respectively. The FI-in-valve column, packed with the resin, enhances the FAAS performance. The spectrophotometric FI system with a column (packed with Chelex-100) placed at the detection point (in a cell holder of a spectrophotometer) is based on the formation of iron (II)-1,10-phenanthroline complex sorbed onto the resin. No eluent has been found to be suitable. The FI-BI for renewable microcolumn has been proven to be an alternative. The FI-FAAS and FI-BI procedures provide online sample preseparation and preconcentration for the determination of iron in beer. Both are simple, rapid, and economical. The procedures also involve sample preparation (decarbonation and suppression of tannin interference by adding ascorbic acid) and standard addition. The results obtained by FI-FAAS and FI-BI agree with those of AOAC spectrophotometric method.