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Archives of Environmental Contamination and Toxicology (v.48, #4)
The Development of Marine Toxicity Identification Evaluation (TIE) Procedures Using the Unicellular Alga Nitzschia closterium by A. C. Hogan; J. L. Stauber; F. Pablo; M. S. Adams; R. P. Lim (pp. 433-443).
Unicellular algae are highly sensitive to a wide range of toxicants and have been used extensively in ecotoxicological testing. This, along with their ability to grow in very small test volumes over short test durations, make them ideal test organisms for use in Toxicity Identification Evaluations (TIEs). Despite this, microalgae have not previously been used in marine TIE studies. In this study, the marine diatom Nitzschia closterium was shown to be a highly suitable test organism after modification of the standard test protocol to reduce test volumes to 6 mL and test duration to 48 h. The alga was tolerant to the chemicals used in phase I of the standard USEPA TIE protocol, and physical TIE manipulations had no effect on algal growth. The cation exchange procedure, however, inhibited algal growth, while the anion exchange procedure stimulated growth, making these two procedures unsuitable for use with this species. Of the buffers trialed for the graduated pH procedure, 0.01 M PIPES buffer was found to be suitable for buffering at pH 7 because it maintained the required pH over the duration of the test and did not affect the growth or sensitivity of the algae to one reference toxicant (copper). A trial TIE on a secondary-treated sewage effluent for discharge into coastal waters showed that the developed protocols could successfully be used to identify ammonia as the major toxicant in the effluent.
Toxicity of the Crude Oil Water-Soluble Fraction and Kaolin-Adsorbed Crude Oil on Daphnia magna (Crustacea: Anomopoda) by F. Martínez-Jerónimo; R. Villaseñor; G. Ríos; F. Espinosa-Chavez (pp. 444-449).
Crude oil is a complex mixture of hydrocarbons entering aquatic environments from accidental or normal marine and transportation activities. Toxicologic crude oil analysis is usually performed on the basis of the water-soluble fraction. However, this yields only a partial estimate of the damage caused by these contaminants because a substantial hydrophobic amount can be adsorbed onto suspended solids (biotic and abiotic), which directly affects filter-feeding species and permits bioaccumulation through trophic relationships. This study determined the acute toxic damage sustained after 48 hours caused by seven types of crude oil from Tabasco, Mexico on the cladoceran Daphnia magna. Comparisons were documented based on the responses of D. magna from application of the water-soluble fraction and exposure to entire crude oil samples adsorbed on kaolin clay. Oil-sorbed kaolin was more toxic than the water-soluble fraction in acute exposure. This confirms that tests of the water-soluble fraction tend to underestimate the toxic damage that can be produced in natural environments. Furthermore, chronic toxicity (21 days) was evaluated for crude oil samples adsorbed on kaolin at sublethal concentrations as established from Application Factors (AF) criteria. Results showed that in most cases, it is impossible to predict safe concentrations on the basis of LC50 values because samples with lower acute toxicity exercised a greater influence on D. magna reproduction and survival when subjected to chronic exposure.
Effects of Acid Mine Drainage and Acidity on the Activity ofChoroterpes picteti (Ephemeroptera: Leptophlebiidae) by A Gerhardt; L Janssens de Bisthoven; A M V M Soares (pp. 450-458).
Survival and behavior of the mayfly Choroterpes picteti (Leptophlebiidae) exposed to acid mine drainage (AMD: pH 3.3–6.4) and a reservoir polluted with arsenic (pH 6.8) from São Domingos mine (Portugal) were studied in laboratory and in situ bioassays (48 h) with the Multispecies Freshwater Biomonitor, and compared with water from a reference river and acidified reference water (acid only). Metal body-burdens showed a negative pH dependency for Mn and As, a positive one for Pb, and for Zn, Cu, Co, and Cd a decrease at pH < 4.4. Generally, survival decreased with decreasing pH. The 48-h LC50 (pH) for AMD and for acid only were similar (pH 4.8–4.9); however, the LT20 (h) at pH 3.3 revealed AMD to be less toxic than acid only. C. picteti show diurnal rhythm with increased locomotor activity in the night. The circadian rhythm was weakened by acid exposure, but less so by AMD exposure. Compared to reference river water, ventilation was stimulated at pH < 6.0 in acid only and in reservoir water. Locomotion was stimulated at pH 5 in acid only and reservoir; however, it was reduced in all other treatments, when compared to reference river water. Under acid-only exposure, both locomotion and ventilation were significantly higher compared to AMD exposure at the corresponding pH values. The laboratory results were field validated.
Bisphenol A in Ambient Air Particulates Responsible for theProliferation of MCF-7 Human Breast Cancer Cells and Its ConcentrationChanges over 6 Months by H. Matsumoto; S. Adachi; Y. Suzuki (pp. 459-466).
To survey the estrogenic activity of the organic extracts from particulate matter of urban ambient outdoor air, samples were collected on glass fiber filters using a high-volume air sampler on the rooftop of our institute for 6 months (six filters/month). After extracting the organic materials and separating them into three fractions, i.e., acidic, neutral, and basic, we applied a cell-growth assay using MCF-7 human breast cancer cells to the original extract and the extracts of the fractions. Only the extract in the acidic fraction showed cell proliferation activity in a dose-response manner. To survey the chemical(s) responsible for the activity, a gas chromatography/mass spectrometry (GC/MS) analysis was conducted after silylating the extract. The presence of bisphenol A (BPA) was confirmed, because the retention times and the MS fragment patterns between the silylated derivative of a component in the sample and that of BPA itself were the same. By using a GC/MS-SIM (selective ion monitoring) technique, the average value was found to be 0.51 ng/m3 of air (range: 0.02 ∼ 1.92 ng/m3 of air). The trend of the residual levels in air particulates showed seasonal variation, increasing from autumn to winter and decreasing from winter to spring. The only exception was that the value in January was lower than those in December and February. Considering the content of BPA in the extract of the acidic fraction and the strength of the activities with the extract and BPA itself, the estrogenic activity due to BPA in the fraction seemed to decrease. In spite of this decline, the possibility remains that the estrogenic activity mainly originated from BPA.
Nonylphenol and Nonylphenol Ethoxylates in River Water, Drinking Water,and Fish Tissues in the Area of Chongqing, China by Bing Shao; Jianying Hu; Min Yang; Wei An; Shu Tao (pp. 467-473).
Little attention has been paid to the estrogenic-like compounds, such as 4-nonylphenol (4-NP) and its potential precursor nonylphenol ethoxylates (NPEOs), in China although its usage is huge. Water samples and corresponding drinking water samples were seasonally collected at five sites of each of the two main rivers in Chongqing Area. Individual nonylphenol ethoxylates (NPEOs) and 4-NP in the Changjiang River and Jialingjiang River were detected by normal-phase liquid chromatography electrospray ionization mass spectrometry and gas chromatography-mass spectrometry. The results indicated that of the five sampling points in the two rivers, NPEOs were the dominant pollutant in April and December with the similar distribution profile, and total NPEOs with different ethylene oxide lengths were 6.9–97.6 μg/L in April and 2.5–52.7 μg/L in December. However, NP was the dominant pollutant in July with a concentration of 1.7–7.3 μg/L. Corresponding drinking water samples derived from river water as source suggested that the conventional water treatment process used in the five waterworks could remove NPEOs from the source water with high removal efficiency (>99%). The 4-NP removal efficiency, however, varied in a range of 62% to 95%, leaving a significantly high concentration of NP (0.1 to 2.7 μg/L) in drinking water in July. Fish samples taken in December 2000 contained 4-NP of ∼1.9μg/g and NPEOs of 0.4–48.3μg/g, with the highest concentration level found in liver.
Organochlorine Concentrations in Bonnethead Sharks (Sphyrna tiburo) from Four Florida Estuaries by J Gelsleichter; C. A. Manire; N. J. Szabo; E. Cortés; J. Carlson; L. Lombardi-Carlson (pp. 474-483).
Because of their persistence in aquatic environments and ability to impair reproduction and other critical physiological processes, organochlorine (OC) contaminants pose significant health risks to marine organisms. Despite such concerns, few studies have investigated levels of OC exposure in sharks, which are fish particularly threatened by anthropogenic pollution because of their tendency to bioaccumulate and biomagnify environmental contaminants. The present study examined concentrations of 29 OC pesticides and total polychlorinated biphenyls (PCBs) in the bonnethead shark (Sphyrna tiburo), an abundant species for which evidence of reproductive impairment has been observed in certain Florida populations. Quantifiable levels of PCBs and 22 OC pesticides were detected via gas chromatography and mass spectrometry in liver of 95 S. tiburo from four estuaries on Florida’s Gulf coast: Apalachicola Bay, Tampa Bay, Florida Bay, and Charlotte Harbor. In general, OC concentrations were significantly higher in Apalachicola Bay, Tampa Bay, and Charlotte Harbor S. tiburo in relation to the Florida Bay population. Because the rate of infertility has been shown to be dramatically higher in Tampa Bay versus Florida Bay S. tiburo, the present findings allude to a possible relationship between OC exposure and reproductive health that requires further investigation. Pesticide and PCB concentrations did not appear to significantly increase with growth or age in S. tiburo, suggesting limited potential for OC bioaccumulation in this species compared with other sharks for which contaminant data are available. Concentrations of OCs in serum and muscle were not correlated with those in liver, indicating that these tissues are poor surrogates for measuring internal OC burden in this species via nonlethal sampling procedures.
Metal Kinetics and Respiration Rates in F1 Generation of Carabid Beetles (Pterostichus oblongopunctatus F.) Originating From Metal-Contaminated and Reference Areas by M. Lagisz; P. Kramarz; M. Niklinska (pp. 484-489).
We investigated resistance to metals in carabid beetles inhabiting metal-polluted and reference areas. Chronic multigeneration exposure to toxic metal concentrations may potentially result in adaptation through decreased metal uptake rate and/or increased excretion rate. The cost of resistance to pollution could be associated with increased metabolic rate. To test these predictions, laboratory cultured F1-generation beetles originating from metal-polluted and reference sites were exposed to food contaminated with zinc and/or cadmium for 10 weeks. After that, uncontaminated food was offered to the animals for another 3 weeks. During the experiment, internal concentrations of Cd and Zn were measured as were respiration rates of the animals. The results obtained show no significant differences in metal accumulation and excretion patterns or respiration rates between the populations. This may suggest that adaptation has not occurred in the beetles chronically exposed to toxic metal concentrations. The possible explanations for the lack of differences between the populations are discussed.
Using Transgenic Caenorhabditis elegans in Soil Toxicity Testing by Amber L. Graves; Windy A. Boyd; Phillip L. Williams (pp. 490-494).
Soil bioassays are important tools for evaluating toxicological effects within the terrestrial environment. The American Society for Testing and Materials E2172-01 Standard Guide outlines a method for conducting laboratory soil toxicity tests using the nematode Caenorhabditis elegans. This method is an efficient tool for extracting C. elegans from soil samples and can be carried out after a 24-h exposure period using relatively small amounts of soil. Drawbacks of this method include problems with (1) recovery of nematodes from soils containing a high percentage of organic matter, and (2) distinguishing indigenous nematode species from nematodes added for the laboratory test. Due in part to these issues, C. elegans has not been extensively accepted for use in soil testing. To address these concerns and improve upon the American Society for Testing and Materials method, this project focused on using transgenic strains of C. elegans carrying a GFP-expressing element. Lethality and behavior tests revealed that the transgenic nematodes respond similarly to the wild-type N2 strain, indicating that they can be used in the same manner in soil testing. The GFP marker is easily identifiable not only within soils containing a large amount of organic matter, but also in field-collected soils containing indigenous nematodes. These results support the use of transgenic GFP C. elegans in soil bioassays as a tool to further the reliability of laboratory toxicity tests.
Toxic Effects of Bisphenol A on Sexual and Asexual Reproduction in Hydra oligactis by N. Fukuhori; M. Kitano; H. Kimura (pp. 495-500).
Hydra oligactis, an evolutionarily primitive invertebrate, produced eggs or testes (sexual reproduction) when starved at 10°C, and produced buds (asexual reproduction) when fed at 20°C. Bisphenol A (BPA) at 2–4 mg/L given to male or female hydra had adverse effects on both sexual and asexual reproduction. Despite the estrogenic nature of BPA, testis formation and egg formation were similarly affected. The doses causing these acute toxicities were comparable to those reported earlier in aquatic invertebrates and were much higher than environmentally detected doses, at which the disruption of the endocrine system has been reported in fishes. All these facts indicate that the adverse effects are the results of general toxicity and may not be due to the estrogenic function of the compound. On the other hand, we found that BPA at 1 mg/L (a dose still much higher than environmental doses) stimulated asexual reproduction. No such stimulation of sexual reproduction was seen. When male hydras were fed at 10°C, they produced both buds and testes simultaneously. BPA at 0.5 and 1 mg/L under this condition also stimulated asexual reproduction, whereas it suppressed sexual reproduction more severely than BPA at 2–3 mg/L. There may be some interaction between processes involved in sexual and asexual reproduction under this condition, and the stimulation of asexual reproduction by BPA may cause suppression of sexual reproduction.
Differences in DDT and PCB Residues Between Common and Striped Dolphins from the Southwestern Mediterranean by A. Borrell; A. Aguilar (pp. 501-508).
Organochlorine concentrations (OCs) and stable isotopes were investigated in the blubber of common dolphins (Delphinus delphis) and striped dolphins (Stenella coeruleoalba) from the southwestern Mediterranean. Samples were obtained from dolphins entangled in fishing nets during the 1992–1994 fishing season and from biopsies taken in 1992. Intrapopulation variations were studied, but because most of the dolphins were juveniles or calves (90%), no significant differences were found on the basis of reproductive condition or sex. Only mature male common dolphins showed significantly higher levels of most of the compounds studied than immature individuals did. There were quantitative and qualitative interspecific differences in organochlorine compounds profile. As compared to common dolphins, striped dolphins carried higher concentrations of organochlorine concentrations (OCs), their %DDE/tDDT and PCB/tDDT ratios were significantly higher, and recalcitrant PCB congeners were more abundant. Distribution and information on composition of stomach contents would in principle support a higher exposure to OCs in common dolphins as compared to striped dolphins, thus apparently contradicting the observed results. However, stable isotopes showed that striped dolphins exploit a higher trophic level, thus explaining observed differences. Interspecific dissimilarities in metabolic capacity to handle OCs may be an added factor. Although in the two species OC concentrations exceeded levels considered to be ineffective in marine mammals, pollution-induced effects on populations could not be properly assessed.
Antioxidant Enzymes and Tissue Regeneration in Eurythoe complanata (Polychaeta: Amphinomidae) Exposed to Used Vehicle Crankcase Oil by O. Nusetti; E. Zapata-Vívenes; M. M. Esclapés; A. Rojas (pp. 509-514).
Polychaetes, Eurythoe complanata, from the Gulf of Cariaco,Venezuela, were exposed to 0.3, 1.6, and 3.3% water-soluble fraction (WSF) of used crankcase oil during 15 and 21 days. The antioxidant enzymes glutathione peroxidase (GPX), glutathione reductase (GR), catalase (CAT), and glutathione-S-transferase (GST) were assayed in the body wall tissue. Furthermore, after chemical exposure, the polychaetes were cut into equal halves; then wound healing and the number of regenerated body segments were recorded periodically. GST activity was affected by all the experimental treatments, with activity increasing with WSF concentrations. GPx activity was altered for the contamination period. GR and CAT activities rose in response to increasing WSF concentrations, and were higher for long-term than for short-term exposures. The wound healing of the transected body regions was retarded by WSF exposure. WSF affected the tissue regeneration, which was almost abolished at 3.3% WSF. The exposure period did not affect the tissue-repairing responses. Alteration of GST in contaminated organisms suggested equivalent changes in detoxication of bioaccumulated organic contaminants. The variation of GR and CAT suggests induction of oxidative stress that could reduce the ability of WSF-exposed worms to repair damaged tissue.
Urinary 8-Hydroxydeoxyguanosine in Belarussian Children Relates to Urban Living Rather Than Radiation Dose After the Chernobyl Accident: A Pilot Study by M. Tondel; A. Arynchyn; P. Jönsson; B. Persson; C. Tagesson (pp. 515-519).
As a result of the Chernobyl accident in 1986, exposure to radioactive cesium is still a concern in the contaminated regions of Belarus. We tested the hypothesis that long-term radiation exposure from the Chernobyl accident might increase the urinary excretion of the oxidative stress marker, 8-hydroxydeoxyguanosine (8-OHdG), in Belarussian children. Urinary 8-OHdG was determined in two groups of children (—n = 31 and n = 46) —living in contaminated and uncontaminated areas of Belarus, respectively (the majority of the unexposed children lived in the capital Minsk). The children from the contaminated areas had a significantly higher annual summary effective dose but significantly lower urinary 8-OHdG levels than the children from the uncontaminated areas. Unexpectedly, children living in uncontaminated urban areas had significantly higher urinary 8-OHdG levels than children living in uncontaminated rural areas. There was no statistically significant effect of sex or body mass index on urinary 8-OHdG, but there was a weak significant inverse correlation to age as well as to the annual summary effective dose. These findings suggest that radiation from the Chernobyl accident is now a less important contributor to oxidative stress in Belarussian children than urban living.
Measures of Resting Immune Function and Related Physiology in Juvenile Rainbow Trout Exposed to a Pulp Mill Effluent by M. R. van den Heuvel; K. O’Halloran; R. J. Ellis; N. Ling; M. L. Harris (pp. 520-529).
Juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 0, 10, 30, and 70% (v/v) of a secondary-treated, integrated thermomechanical-bleached kraft pulp and paper mill effluent. The immunological parameters oxidative burst and phagocytosis of head kidney macrophages and total and differential circulating leukocytes were measured after 21 d of exposure. General parameters of stress and exposure including erythrocyte counts, numbers of degenerating erythrocytes, splenic pigmented macrophage aggregates (PMAs), spleen size, bile chemistry, and hepatic EROD activity were also assessed. Contrary to parallel chronic studies on the same effluent, EROD induction did not occur. Analyses of bile indicated uptake and accumulation of resin acids and some sterols. There was no measurable macrophage-related immunological dysfunction. However, circulating leukocytes, specifically lymphocytes, were reduced. The density of splenic PMAs increased over the exposure period, possibly in association with degenerating blood cells. There were statistical differences between staggered days of sampling in head kidney oxidative burst, white and mature red blood cell counts, and spleen size, indicating that relatively minor capture and handling stress could result in rapid changes in some parameters. Overall, it was concluded that the observed minor, indirect alterations in the immune response were likely the result predominantly of a nonspecific mechanism such as a cortisol-mediated stress response.
Heavy Metal Levels in Fish from Coastal Waters of Uruguay by F Viana; R Huertas; E Danulat (pp. 530-537).
Copper, mercury, and zinc levels were determined in muscle and liver (N = 163) of seven fish species caught in coastal waters off Montevideo and Piriápolis (control site): Odontesthes spp., Mugil platanus, Micropogonias furnieri, Urophycis brasiliensis, Cynoscion guatucupa, Menticirrhus americanus, and Mustelus schmitti. The local population commonly uses these species for consumption. Heavy metal concentrations determined in this study were generally below those obtained for fish caught in Argentinean and Brazilian coastal waters, with some exceptions in the case of mercury and zinc. Based on copper, mercury, and zinc levels in muscle tissue, we conclude that the fish studied here are acceptable for human consumption. Nevertheless, it is recommended not to consume the fish liver (up to 466 μg Zn g−1 dry weight in liver) nor large specimens of the investigated species. Regional programs involving the neighboring countries should be established to assess the fisheries resources and potential risks for human health.
Analysis of UNEP Priority POPs Using HRGC-HRMS and Their Contamination Profiles in Livers and Eggs of Great Cormorants (Phalacrocorax carbo) from Japan by Kurunthachalam Senthil Kumar; Kiyohiko Watanabe; Hiroaki Takemori; Naomasa Iseki; Shigeki Masunaga; Takumi Takasuga (pp. 538-551).
The present investigation demonstrates establishment of United Nations Environment Programme (UNEP) priority Persistent Organic Pollutants (POPs) using high-resolution gas chromatography–high-resolution mass spectrometry. Particularly, POPs analytical methods were established using native and 13C-labeled internal standards of HCHs, HCB, cyclodienes, chlordanes, DDTs, mirex, dioxin-like PCBs, PCDDs, and PCDFs by isotope dilution technique. The relative response factor for 6-point calibration curve native standards (18 replicate analysis) were in the ranges of 0.93–1.43 with relative standard deviation ranges from 1.68 to 4.96%. Instrument detection limit and instrument quantification limit was established for various POPs at femtograms. Concentrations of UNEP-POPs were measured in liver (n = 10) and egg (n = 10) of great cormorants and their major diet, gizzard shad (n = 2), collected in and around Tokyo, Japan. DDTs (ranges in liver and egg, respectively) were predominant accumulants (9800–310,000 and 9600–73,000) followed by dioxin-like PCBs (4500–69,000 and 7900–150,000), chlordanes (2600–16,000 and 700–4,800), cyclodienes (650–4600 and <1–1000), HCB (680–2800 and 180–590), HCHs (230–1800 and 120–490), PCDD/DFs (3.2–27 and 1.7–5.7) on nanogram per gram lipid basis. Concentrations (ranges) of POPs in gizzard shad were in the following order: DDTs (3900–16,000), chlordanes (3400–14,000), cyclodienes (340–1300), HCB (110–480), and HCHs (140–360) on nanogram per gram lipid basis.
Isolation, Cryopreservation, and Mitogenesis of Peripheral Blood Lymphocytes from Chickens (Gallus domesticus) and Wild Herring Gulls (Larus argentatus) by E. T. Lavoie; K. A. Grasman (pp. 552-558).
Monitoring the toxicity of environmental contaminants on the physiologic function of wild birds often includes measures of immune function. The purpose of this study was to apply methods of isolation, cryopreservation, and cell culture of chicken lymphocytes to blood samples from herring gulls, which are a sentinel species for biomonitoring studies in the Great Lakes and northern North America. Slow-spin centrifugation and density gradient isolation of lymphocytes were compared using chicken blood. Significant thrombocyte contamination of density gradient isolated samples (40% to 77% thrombocytes) led to the use of slow-spin centrifugation (2% thrombocytes) for blood from herring gulls. Cryopreserved blood samples were collected from adult and prefledgling herring gulls at sites of low environmental contamination around the Great Lakes and the Bay of Fundy between 1999 and 2002. Cryopreservation decreased the viability of lymphocytes from wild birds, but a high proportion of samples yielded enough live lymphocytes to assess function in culture. Cryopreserved lymphocytes from herring gulls proliferated in response to phytohemagglutinin (PHA), concanavalin-A, phorbol myristate acetate (PMA), PHA plus PMA, and lipopolysaccharide stimulation. Weber and Roswell Park Memorial Institute medium (RPMI) 1640 media were compared for culture of lymphocytes. Weber medium better supported chicken B-lymphocyte proliferation than RPMI 1640 and supported chicken T-lymphocyte proliferation of a similar magnitude as RPMI. Proliferation responses for lymphocytes from prefledgling herring gulls were stronger in Weber medium than RPMI medium, especially for PHA, for which there was no stimulation in RPMI. Proliferation responses of lymphocytes from adult herring gulls were up to twofold greater than that for prefledgling herring gulls. The magnitudes of proliferation responses were similar to that for chicken lymphocytes. These methods have subsequently proven useful in ecotoxicology studies that involve species in remote locations.
Perfluorinated Compounds in Aquatic Organisms at Various Trophic Levels in a Great Lakes Food Chain by Kurunthachalam Kannan; Lin Tao; Ewan Sinclair; Stephanie D Pastva; Dave J Jude; John P Giesy (pp. 559-566).
Trophic transfer of perfluorooctanesulfonate (PFOS) and other related perfluorinated compounds was examined in a Great Lakes benthic foodweb including water–algae–zebra mussel–round goby–smallmouth bass. In addition, perfluorinated compounds were measured in livers and eggs of Chinook salmon and lake whitefish, in muscle tissue of carp, and in eggs of brown trout collected from Michigan. Similarly, green frog livers, snapping turtle plasma, mink livers, and bald eagle tissues were analyzed to determine concentrations in higher trophic-level organisms in the food chain. PFOS was the most widely detected compound in benthic organisms at various trophic levels. Concentrations of PFOS in benthic invertebrates such as amphipods and zebra mussels were approximately 1000-fold greater than those in surrounding water, which suggested a bioconcentration factor (BCF; concentration in biota/concentration in water) of 1000 in benthic invertebrates. Concentrations of PFOS in round gobies were two- to fourfold greater than those in their prey organisms such as zebra mussels and amphipods. Concentrations of PFOS in predatory fishes (Chinook salmon and lake whitefish) were 10 to 20-fold greater than those in their prey species. Concentrations of PFOS in mink and bald eagles were, on average, 5- to 10-fold greater than those in Chinook salmon, carp, or snapping turtles. Because of the accumulation of PFOS in liver and blood, the biomagnification factor (BMF) of perfluorinated compounds in higher trophic-level organisms such as salmonid fishes, mink, and eagles were based on the concentrations in livers or plasma. Overall, these results suggest a BCF of PFOS of approximately 1000 (whole-body based) in benthic invertebrates, and a BMF of 10 to 20 in mink or bald eagles, relative to their prey items. Eggs of fish contained notable concentrations of PFOS, suggesting oviparous transfer of this compound. PFOA was found in water, but its biomagnification potential was lower than that of PFOS.
Residues of Toxaphene in Insectivorous Birds (Petrochelidon spp.) From the Rio Grande, Texas by K. A. Maruya; K. L. Smalling; M. A. Mora (pp. 567-574).
Although it has been documented that wildlife in the Rio Grande Valley (RGV) contain increased concentrations of organochlorine (OC) contaminants, particularly DDE, little has been published on residues of toxaphene throughout this major North American watershed. In this study, 28 liver composites from adult swallows (Petrochelidon spp.) collected along the Rio Grande from 1999 through 2000 were analyzed for toxaphene residues using congener-specific gas chromatography–electron-capture negative ionization–mass spectrometry. Estimated total toxaphene concentrations ranged from 12 to 260 ng/g wet wt and were highest in samples from the lower RGV near Llano Grande Lake in Hidalgo and Cameron counties (Texas). Toxaphene congener profiles were relatively invariant throughout the watershed and were dominated by 2,2,5-endo,6-exo,8,8,9,10-octachlorobornane (P-42a or B8-806) with lesser amounts of several other Cl7-Cl9 compounds, many of which remain unidentified. Petrochelidon spp. liver profiles appear to be intermediate in complexity between those in invertebrates and fish (more complex) and mammals (less complex) and differs somewhat from those reported for other avian species. In addition to other legacy OC contaminants, toxaphene residues were most concentrated in the lower RGV and accumulated at up to hundreds of parts per billion in these insect-eating birds, underscoring their utility as avian bioindicators of persistent organic pollutants.
Estrogenic and Dioxin-like Activities and Cytotoxicity of Sediments and Biota from Hong Kong Mudflats by H. L. Wong; J. P. Giesy; W. H. L. Siu; P. K. S. Lam (pp. 575-586).
Persistent organic pollutants, such as organochlorine insecticides and polychlorinated biphenyls (PCBs), were measured in several environmental matrices including aerial deposition, seawater, sediment, and biota in two important coastal wetlands of Hong Kong, China. Specifically, samples were collected from within the Mai Po Marshes Nature Reserve (Mai Po), an internationally acclaimed wetland situated in the northwestern part of the New Territories of Hong Kong, and A Chau in Starling Inlet, a relatively remote island on the eastern side of Hong Kong. Hexachlorobenzene, dichlorodiphenyltrichloroethanes, and hexachlorocyclohexanes were detected in all samples collected from Mai Po. Environmental endocrine disruptors (including dioxin-like compounds and estrogenic chemicals), measured by the use of cell-based chemical activated luciferase expression assays, were found to occur at concentrations that might pose a risk to the ecologic systems in Mai Po. Dioxin-like PCBs were detected at small concentrations in some of the samples. Concentrations of 2,3,7,8 tetrachlorodibenzo-p-dioxin equivalents (TEQs) were primarily related to the relatively great concentrations (>100 ng/g dry weight) of high molecular–weight polycyclic aromatic hydrocarbons in sediments, whereas the relative proportion of TEQs contributed by nonortho-substituted PCBs was small. Polar compounds primarily contributed estrogen equivalents, which were measured in sediments. Significant concentrations of cytotoxic compounds were detected in fish samples collected from the Mai Po but not in fish collected from A Chau.