P136 (DAU-1117-807746) PCB and PBDE accumulation in great tit (Parus major) eggs and nestlings.
Start time: 8:00 AM
Dauwe, T.¹, Jaspers, V.L.B.¹, Covaci, A.², Eens, M.¹, ¹ University of Antwerp, Laboratory of Ethology² University of Antwerp, Toxicological Centre
Polyhalogenated aromatic hydrocarbons (PHAHs) are a major class of pollutants that have attracted much attention from ecotoxicologists. Although the production and use of some PHAHs was banned, such as PCBs, high concentrations are still being found. Polybrominated diethyl ethers (PBDEs) are a class of brominated compounds that are being used as flame retardants in numeruous applications. Since 1990, PBDEs are being found in increasing concentrations in the environment. The lipophilic characteristic and low biodegradability of PHAHs, render species high on the food chain particularly susceptible. Increasingly however, also insectivorous passerines are being used as sentinel species for PHAH contamination. In this study we examined the levels of PCBs and PBDEs in great tit (Parus major) eggs, nestlings and Lepidoptera larvae, the main food item of nestlings. In two study sites near Antwerp (Belgium), we collected 1 egg and 3 nestlings (5, 10 and 15 days post-hatching) from 22 nests in total. Concentrations and profiles of different PCB and PBDE congeners will be compared. Results will be presented at the conference.

P137 (LIE-1117-834714) Seasonal dynamics in bioaccumulation of PCBs by Chesapeake Bay striped bass.
Start time: 8:00 AM
Liebert, D¹, Baker, J¹, ¹ University of Maryland Chesapeake Biological Laboratory, Solomons, MD, USA
Striped bass from Chesapeake Bay were collected in spring and fall from 1999 to 2003 and analyzed for lipid content and polychlorinated biphenyls (PCBs). These fish showed a strong seasonal pattern of lipid and PCB concentrations with maxima of both in spring and minima of both in fall. As well, a seasonal difference in relative abundance of more chlorinated (heavy) versus less chlorinated (light) PCB congeners was observed. In spring, striped bass PCBs were dominated by lighter, more labile PCBs while PCBs in striped bass collected in fall were dominated by heavier more lipophilic congeners. To investigate a possible cause for our observations, we used a bioenergetic model for Chesapeake Bay striped bass and field measurements to generate lipid, consumption, and ventilation inputs for a toxicokinetic bioaccumulation model. This model demonstrated that seasonality of energetic status and respiration rates can account for the observed seasonal differences in PCB congeners. During summer and fall months when temperatures are high, respiration and ventilation rates are at a maximum and lipid content is at a minimum; these conditions allow for a rapid efflux of lighter, more labile PCB congeners, while heavier congeners remain bound in tissues. This model also suggests that the seasonal efflux of lighter PCB congeners is responsible for deceased total PCBs.

P138 (PHE-1117-716967) Identification of PCB, PAH and Chlordane Source Reaches in the Anacostia River Watershed, MD/DC.
Start time: 8:00 AM
Phelps, H¹, ¹ University of the District of Columbia, Washington, DC, USA
The freshwater Anacostia River estuary of Washington, DC is one of three Areas of Concern in the Chesapeake Bay. It has a fishing advisory for PCBs and chlordane and a depauperate benthos with high tumor incidence in resident fish. Two-week active biomonitoring with Corbicula fluminea clams has been found effective and was used to assess significant levels of bioavailable EPA Priority Pollutants and six metals in first and second order tributaries of the Anacostia River watershed. Clams placed in one tributary (Lower Beaverdam Creek) had significant PCB and Aroclor accumulation starting at the highest of several industrial centers. High PAH bioaccumulation was found at many sites in the Northeast Branch with greatest concentrations associated with three industrial centers. High chlordane bioaccumulation was found at only one second-order stream of the Northeast Branch which was not associated with any industrial center. Clams placed in the Northwest Branch had no significent bioaccumulation of pesticides, PCBs or PAHs. No significant pollutant bioaccumulation was found in the Beltsville Agricultural Center drainage. No metal levels exceeded control levels in nearby Potomac River clams. All of the most contaminated watershed sites except two were located in the Maryland counties around DC.

P139 (GRA-1117-835508) Lymphocyte proliferation in adult and prefledgling herring gulls exposed to environmental contaminants in the Great Lakes.
Start time: 8:00 AM
Ramanunni, A¹, Grasman, K¹, Fox, G², ¹ Wright State university, Fairborn, Ohio, U.S.A² Canadian Wildlife Service, Ottawa, Ontario, Canada
Developmental and chronic exposure to organochlorine contaminants has been associated with suppression of T cell-mediated immune responses in fish-eating birds such as gulls and terns. Organochlorines can increase or decrease lymphocyte proliferation in laboratory studies. The objective of this study was to assess lymphocyte proliferation in Great Lakes herring gulls (Larus argentatus) exposed to organochlorines. Blood samples were collected during 2003 from adult and prefledgling herring gulls from Chantry Island (C) (reference site) and Saginaw Bay (SB) in Lake Huron, and Hamilton Harbor (HH) and Scotch Bonnet Island (S) in Lake Ontario. Adult birds were trapped during mid-incubation. Herring gull chicks were sampled at 3 and 4 weeks after hatch. Lymphocytes were isolated by slow spin centrifugation and cryopreserved. After thawing, lymphocytes were cultured with T-cell (ConA, PHA + PMA) and B-cell (LPS) mitogens for 48 hours. Proliferation was measured by ELISA using 5-Bromo-2′-deoxy-uridine incorporation assay and expressed in terms of stimulation index: mean optical density in mitogen-stimulated wells divided by mean optical density in non-stimulated wells. Lymphocyte samples had good viability post thaw (mean=80%) and showed strong proliferation in response to mitogens. In adults, T-cell proliferation was increased at SB compared to C (30% for PHA+PMA; 60% for Con A), and B-cell proliferation was decreased 40% at SB and 32% at HH. In 3 week old chicks, Con A-induced proliferation was increased 50% at HH. At SB proliferation with PHA+PMA was increased 25%, and at S B-cell proliferation was increased 65%. Four week old chicks showed significant proliferation but no significant intersite differences. This study demonstrated that mitogen-induced proliferation assays using cryopreserved lymphocytes are useful indicators for assessing immune function in wild birds. The differences in proliferation in Great Lakes herring gulls from different sites may be associated with environmental contaminants.

P140 (BAY-1118-131501) Polybrominated diphenyl ethers (PBDEs) in Singapore.
Start time: 8:00 AM
BAYEN, S.¹, LI, Q.Q.², WURL, O.³, OBBARD, J.³, ¹ Department of Inorganic, Analytical and Applied Chemistry (CABE), University of Geneva, Geneva, Switzerland² Department of Obstetrics & Gynaecology, National University of Singapore, Singapore, Singapore³ Tropical Marine Science Institute, National University of Singapore, Singapore, Singapore
PBDEs are widely used as flame retardants in a range of construction materials, textiles and other consumer products, such as electronics. Although environmental levels of PBDEs can be traced back to the 1970 ′s in Europe and America, there is no existing data in South-East Asia prior to 2002. Consumption of PBDEs in Asia reached 24,650 metric tons in Asia in 2001, less than 1% of which corresponded to the pentachlorinated diphenyl ether formulations (www.bsef.com). Although measures have been taken in Europe, America and Japan, to curtail usage of certain PBDEs, there is currently no existing legislation in the Asia-Pacific region restricting the use of PBDEs. This report collates data on the levels of PBDEs in air, seawater, marine sediments, marine biota, seafood and human tissues in Singapore, from our various studies, conducted since 2002. It is apparent from the data, that PBDEs, and particularly BDE-47, 99 and 100, are ubiquitous in Singapore's marine environment. Additionally, the presence of 'hot-spots' of contamination suggest the presence of local sources of PBDEs. Data from Singapore are discussed within the international context. The present report reflects the need for a more extensive investigation of PBDEs in a range of environmental media in South-East Asia.

P141 (KAN-1117-809619) Accumulation of Chlorinated, Brominated and Perfluorinated Compounds in Polar Bears from Alaska.
Start time: 8:00 AM
Yun, S.¹, Evans, T.², Kannan, K.¹, ¹ Wadsworth Center, New York State Department of Health, Empire State Plaza, PO Box 509, Albany, NY 12201-0509, USA² U.S. Fish and Wildlife Service, Anchorage, Alaska, USA
Organochlorine pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs) and perfluorinated compounds (PFCs) were measured in the liver of polar bears (n=36) collected from Alaska in the late 1990s. Concentrations of total PCBs in polar bears ranged from 146 to 2820 (mean: 560) ng/g, wet wt. Hexa- and hepta-chlorobiphenyls were the predominant congeners found. Concentrations of PBDEs in polar bear livers ranged from <0.1 to 3.2 (mean: 1) ng/g, wet wt. PBDE47 was the only congener detected in polar bear livers. Among pesticides, oxychlordane was the major compound found in the livers of polar bear from Alaska. Oxychlordane levels ranged from 19 to 2660 (mean: 577) ng/g, wet wt. Concentrations of DDTs, HCHs and HCB were relatively low. Among perfluorinated acids analyzed, PFOS was the major contaminant. Concentrations of PFOS in livers of polar bears ranged from 175 to 700 (mean: 350) ng/g, wet wt. Concentrations of other perfluorinated acids such as PFOA, PFHS and PFOSA were relatively lower than that of PFOS or remained not detected. No age- or gender- related accumulation in perfluorinated compounds was discerned in polar bears. Concentrations of most of the target compounds analyzed in this study were less than those reported for polar bears from Canadian or Norwegian Arctic.

P142 (WIE-1117-803565) Blood lead concentrations in outdoor living cats in Tampa, Florida.
Start time: 8:00 AM
Wiesen, L¹, ¹ University of South Florida, Tampa, FL, USA
Where lead pollutes urban soils, both human and animals risk exposure. This exposure gives rise to similar health risks across species. A group of 50 outdoor living cats from inner city Tampa, Florida were tested for blood lead concentration (BLC). Most cats had no measurable lead loads, 14% had levels ≤6 g/dl. Previous studies of soil lead pollution in Tampa have found lead levels ranging from 0-1100 ppm (mean 65 ppm, median 40 ppm). The highest levels are localized in older neighborhoods and adjacent to high traffic roads. The cats with measurable BLCs originated in these types of locations. Overall, BLCs were lower than expected. In addition, the BLCs were lower than those found in older industrial cities. The reduction of the use of lead as well as Tampa′s location in the newly developed Sunbelt, may be responsible for the overall low levels found in the region′s outdoor living cat population.

P143 (MUR-1117-859147) Design and Performance of a Constructed Wetland for Remediation of Copper in a Wastestream (2001 and 2005).
Start time: 8:00 AM
Murray Gulde, C¹, Heatley, J², Huddleston, G², Rodgers, Jr., J³, Eggert, D³, ¹ ENTRIX, Atlanta, GA, USA² ENTRIX, Pendleton, SC, USA³ Clemson University, Department of Forestry and Natural Resources, Clemson, SC, USA
Performance was evaluated in an eight-acre constructed wetland treatment system receiving copper-contaminated water since October 2000. The constructed wetland used in this research was designed using theoretical and physical modeling with the primary objective of poising the system to limit copper bioavailability. Performance objectives for this constructed wetland treatment system were to decrease total recoverable copper to <22 g/L and to eliminate toxicity (Ceriodaphnia dubia; 7-d, static/renewal). From March 2001 until April 2002 the constructed wetland system was extensively monitored and evaluated for performance and functional contributions of Schoenoplectus californicus, giant bulrush, and wetland hydrosoil in limiting copper bioavailability. During the 2001 - 2002 investigation, inflow wastewater concentrations averaged 27 (±11) g Cu/L and outflow averaged 3 (±2) g Cu/L, with 89% (±8) overall copper removal. Inflow water was toxic to C. dubia, while no toxicity was observed in outflow water. The current research (2005) evaluated the performance and functional roles of the vegetation and hydrosoil following five years of continuous operation. Since coming online, this constructed wetland system has consistently achieved >80% decrease in copper concentrations and no observed toxicity to C. dubia. Hydrosoil redox potential and AVS indicate that the system continues to be poised for limiting bioavailable copper, with no adverse seasonal effects on wetland performance. In addition to evaluating copper removal, removal of other constituents of concern present in the wastewater (mercury and zinc) was measured.

P144 (AAA-1117-221242) PCB accumulation in osprey and snapping turtles exposed to point sources.
Start time: 8:00 AM
de Solla, S¹, Martin, P¹, Fernie, K¹, ¹ Canadian Wildlife Service, Burlington, Ontario, Canada
We examined the accumulation of PCBs in osprey (Pandion haleaetus) eggs and plasma at Sturgeon Lake, which were collected over a range of 14 km (0.2 - 14.2 km) from a point source. Similarly, eggs of snapping turtles (Chelydra serpentina) were collected from Lyons Creek, over a range of 7.5 km (3.2 - 10.8 km) from the Welland Canal (Niagara River AOC). Although there was a weak relationship between the distance to the point source and sum PCBs in osprey eggs, sum PCB concentrations declined in osprey chick plasma with the distance from the point source. The PCB congener profile in osprey plasma varied both with distance to the point source and with sum PCBs. Both eggs and plasma indicated a local Aroclor 1254/1248 source, which contrasts with the relatively small contribution of these Aroclors in other Great Lake colonies of osprey. Sum PCBs in turtle eggs declined with increasing distance between the nest and the Welland Canal. Similarly, the relative contribution of Aroclor 1254/1248 declined with sum PCBs, and with the distance from the nest to the canal. Compared to turtle eggs from most other sites in Lake Erie and Lake Ontario, eggs from Lyons Creek had a strong contribution of Aroclor 1254/1248.

P145 (MCK-1117-742801) Mercury and methyl mercury loads entering San Francisco Bay from the New Almaden historic mercury mines.
Start time: 8:00 AM
McKee, L¹, Leatherbarrow, J¹, ¹ San Francisco Estuary Institue, Oakland, CA, United States
San Francisco Bay is listed by the State of California as impaired for mercury (Hg). The largest proportion of current Hg loads to the Bay is derived either directly or indirectly from the historic New Almaden Mining District, the largest producer of Hg in North America between 1850 and 1975. This paper presents Hg monitoring data collected from autumn 2002 to spring 2005 during intensive sampling during floods on the Guadalupe River downstream from the historic mines and greater San Jose. During the first two years of sampling, total Hg (HgT) was measured along with suspended sediment concentration (SSC), other trace metals, and organic carbon. The third year included total dissolved Hg (HgD), total methyl Hg (MeHgT), and dissolved methyl Hg (MeHgD). Since Hg is mostly transported with sediment particles, a turbidity sensor was used to derive 15-minute SSC data to help interpret Hg release and transport processes. Hg measured in bed load accounted for <5% of the total load. To date, 105 Hg samples have been collected during the full range of flow conditions. Maximum concentrations of HgT and MeHgT were 19,000 ng/L and 2 ng/L, respectively. These elevated concentrations reflect the dominant influence of mercury release from the mining area and exceed previously observed concentrations in river systems polluted from urbanization alone. Due to differences in climatic forcing and mercury release, annual water column HgT loads over the period of study have ranged between approximately 9 kg and 116 kg. We suggest that maximum water column HgT loads might be 10 times greater during the wettest years. These new HgT load estimates have helped refine existing perceptions about the supply of mercury to the Bay and prioritize management actions aimed at reducing water quality impairment.

P146 (DAV-1117-748925) Mercury Transport to San Francisco Bay through the Sacramento-San Joaquin River Delta.
Start time: 8:00 AM
David, N¹, Leatherbarrow, J¹, McKee, L¹, ¹ San Francisco Estuary Institute, Oakland, CA, United States
San Francisco Bay is currently listed as impaired on the Clean Water Act 303(d) list for mercury due primarily to elevated concentrations in sport fish and the issuance of current fish consumption advisories. The large magnitude of sediment and runoff entering San Francisco Bay through the Sacramento-San Joaquin River Delta makes these major rivers important transport pathways for mercury and other particle-associated contaminants. Historic gold and mercury mining in the Sierra Nevada and Coast Range Mountains as well as expanding urbanization in the Central Valley of California are ongoing sources of mercury to the Bay. Between January 2002 and January 2005, water samples were collected at a downstream location of the Sacramento River to quantify mercury concentrations and loads in surface runoff associated with large storm events and re-suspension of river sediments. Mercury concentrations ranged from 3.2 to 14 ng/L and showed a strong correlation (r2 = 0.8) to suspended sediment concentrations. The collection of continuous turbidity measurements by U.S. Geological Survey at the study location allowed for extrapolation of the suspended sediment record to estimate daily average total mercury loads. For the first two years of monitoring in water years (WYs) 2002 and 2003, daily mercury loads ranged from 3 to 1,800 g, while annual mercury loads were approximately 58 ± 20 kg in WY 2002 and 97 ± 20 kg in WY 2003. Preliminary load estimates for WYs 2004 and 2005 reflect annual mercury loads of similar magnitudes. Results from this study have helped refine current estimates of mercury loads to the Bay from the Sacramento-San Joaquin River system. In the context of other significant transport pathways and numerical models, these refined estimates will further assist in understanding the long-term fate of mercury and recovery of impaired waters of the Bay.

P148 (HEI-1115-845624) Species differences in sensitivity of birds to methylmercury.
Start time: 8:00 AM
Heinz, G¹, Hoffman, D¹, ¹ USGS Patuxent Wildlife Research Center, Laurel, MD, USA
Many species of birds live in aquatic habitats that are contaminated by mercury. Methylmercury is the predominant chemical form of mercury in the foods of aquatic birds, and this form is highly toxic to avian embryos. Therefore, avian reproduction is considered to be a sensitive indicator of mercury pollution. The reproductive success of some avian species, such as the common loon, is thought to be sensitive to mercury contamination, and estimates have been made of the levels of mercury in the diet and eggs of loons that may cause harm. Unfortunately, little information is available from the field to determine the sensitivity of other avian species to mercury contamination. More field research is need for other species, but controlled studies in which captive pairs of breeding birds are fed different levels of methylmercury is another way differences in species sensitivity can be studied. However, given the great cost and time required to conduct controlled feeding studies with wild birds, few such studies are likely to be carried out. Consequently, concentrations of mercury in eggs considered to be harmful have come mostly from controlled laboratory studies with species such as game farm mallards and ring-necked pheasants. How the sensitivity of the game farm species compares to that of wild birds is unknown. We have been using egg injections to compare the embryo sensitivities of many wild birds to methylmercury, and this technique has shown that some species are more sensitive than the game farm species. Combinations of field studies, captive feeding studies, and egg injections will be needed to arrive at a more complete picture of how birds may differ in their sensitivity to methylmercury.

P150 (NAM-1117-742059) Longitudinal monitoring of persistent organic pollutants in UK breast milk: correlation with genotoxicity.
Start time: 8:00 AM
Nam, J. J.^{1, 2}, Hewitt, R.³, Martin, F.³, Jones, K.², ¹ Department of Environmental Science, Institute of Environmental and Natural Sciences, Lancaster University, Lancaster, UK² National Institute of Agricultural Science and Technology, Suwon, Korea³ Department of Biological Sciences, Institute of Environmental and Natural Sciences, Lancaster University, Lancaster, UK
The importance of exogenous exposures in the aetiology of breast cancer remains to be established. Through environment or diet, humans are continuously and variously in contact with fat-soluble xenobiotics that may elicit effects, often damaging, either singly or in mixtures. In order to simulate in vitro the potential effects of in vivo human exposures, we employed milk fat as a surrogate tissue; persistent organic pollutants (POPs) in adipose tissue may be excreted during lactation. Longitudinal analyses for fluctuations in POP concentrations in milk-fat extracts (n = 5 UK-resident mothers) collected over a one-month period (on six different days) were conducted. Geometric means and ranges of the sum of five PBDE congeners, DDT/DDEs, 33 PCB congeners, and HCB were 2.5 (0.4-8.3), 107 (15-9260), 59 (16-220), 8.5 (5.2-12) ng/g lipid, respectively. Although information on the exact date post-partum that samples were collected was not made available, one could assume that the first sample per series was collected within one month of the start of lactation. In light of this, a general trend where POP levels were elevated towards the middle part of the collection series and began to decline towards the end was noted. The highest to lowest ratios of PBDE, DDT, PCBs, and HCB were 21, 3, 14, and 2, respectively; similar to observed ratios in air. These low ratios for DDT, PCB, and HCB suggest that these compounds are currently not being used whereas the higher PBDE ratio might be suggestive of extensive use throughout the UK due to stringent fire regulations. In parallel experiments, "low-dose" effects of such contaminant mixtures present in milk-fat extracts were examined in MCF-7 cells using the cytokinesis-block micronucleus assay and the alkaline COMET assay. Such an approach may provide evidence as to whether such exposures modulate the susceptibility of target-cell populations to pathogenic events.

P151 (JEN-1118-359910) Bioaccumulation of perfluorooctanesulfonate (PFOS) in aquatic organisms.
Start time: 8:00 AM
Jenkins, K¹, Pittinger, C², Huntley, S¹, Pawlisz, A³, Anthony, A⁴, Santoro, M⁵, ¹ BBL Sciences, Petaluma, CA, USA² BBL Sciences, Cincinnati, OH, USA³ BBL Sciences, Tampa, FL, USA⁴ BBL Sciences, Carpinteria, CA, USA⁵ 3M Research and Development, St. Paul, MN, USA
Perfluorooctanesulfonate (PFOS) and related perfluoroalkyl compounds were used extensively as chemical intermediates and as oil- and water-resistant coatings for paper, textiles, and other products. Recently, PFOS has been detected in various wildlife species and questions have been raised regarding the potential of this compound to bioaccumulate in aquatic food chains. Estimates of bioaccumulation factors (BAFs) for PFOS from field studies vary by orders of magnitude. There are several problems with using existing field data as a basis for developing BAFs. First, this approach does not account for the additional contribution of metabolite-derived PFOS to the total PFOS tissue concentration. The failure to account for metabolite-derived PFOS in the denominator results in a systematic overestimation of the BAF. Second, field derived BAFs are often based on liver tissue or blood PFOS concentrations rather than whole body tissue concentrations. BAFs derived in this manner are not useful for understanding trophic level transfer of PFOS since predator species consume whole body tissue, not individual organs. In this paper we evaluate the bioaccumulative potential of PFOS in aquatic food chains.

P152 (BAR-1117-827879) Low-dose effects of polybrominated diphenyl ethers (PBDEs) in MCF-7 cells.
Start time: 8:00 AM
Barber, J¹, Hewitt, R¹, Jones, K¹, Martin, F¹, ¹ Lancaster University, Lancaster, Lancashire, UK
The release of PBDEs to the environment is increasingly being regarded as an environmental hazard. PBDEs can bioaccumulate and biomagnify, and increasing human-tissue concentrations have been detected in the last decade. We examined in MCF-7 breast cells the ability of four PBDE congeners (PBDEs-47, -153, -183 and -209) to elevate levels of chromosomal damage, measured as micronuclei in the cytokinesis-block micronucleus assay, compared to an appropriate vehicle control. These congeners are among the most abundant congeners found in human samples. Parallel experiments examining growth kinetics, clonogenic survival and quantitative expression, using real-time RT-PCR, of cytochrome P450 isoenzymes CYP1A1, CYP1A2 and CYP1B1 were also conducted. The ability of PBDEs to induce effects over a range of concentrations (10^-12 M to 10^-6 M) was explored. Marked elevations (2- to 5-fold) in micronucleus formation were observed following 24-h treatment with 10^-12 M, 10^-11 M, 10^-10 M or 10^-9 M PBDE congener; often not in a dose-response fashion but as a characteristic bell-shaped curve, the extent of PBDE-induced micronucleus formation appeared to be modulated between experiments by background levels i.e. the lower the background level the more profound the induced effect. While clonogenic survival was not altered, growth kinetics over 72-h incubation was up to 30% elevated. Reductions in CYP1A1, CYP1A2 and CYP1B1 expression occurred after 24-h PBDE treatment i.e. PBDE-153 reduced CYP1A1 expression to 10% compared to the calibrator control. Currently, the micronucleus origin (aneuploid Vs. clastogenic) using kinetochore antibody probes, and intra-cellular conformation changes using near-field micro-spectroscopy, are being investigated to further characterise these effects. Our results suggest that PBDEs are capable of inducing effects at low-dose levels that would be close to environmental exposures. Whether such effects in an oestrogen receptor-positive breast carcinoma immortalised cell line translate into a potential to modify susceptibility in relevant target cells remains to be explored.