bluuebunny/crossref_metadata_2025_split huggingface dataset:
Growth of fathead minnows in oilsand-processed wastewater in laboratory and field
Authors: Siwik Paula L , Van Meer Terry , MacKinnon Michael D , Paszkowski Cynthia A 
Published: March 2010

AbstractTwo waste products of Syncrude Canada Ltd. (SCL) oilsands mine are mature fine tailings (MFT), a toxic aqueous suspension of particles, organic acids, bitumen, and metals, and tailings pond water (TPW), a saline solution containing organic and inorganic contaminants. The chemical profiles of MFT interstitial water and TPW are very similar. Syncrude Canada has proposed disposing of MFT in constructed lakes, which would be lined with MFT and capped with clean water. As the MFT consolidates, MFT-associated water would be released into the overlying watercap. Prototype ponds support fathead minnows (Pimephales promelas), but the long-term viability of these populations is unknown. This study attempts to determine if exposure to MFT and TPW, a related waste product, affected growth of fathead minnow larvae in the laboratory and field. Laboratory larval growth bioassays (7 and 56 d) on whole effluent from numerous prototype ponds yielded no significant differences in dry weight, but one 7-d bioassay showed reduced survival in two SCL sites. A 56-d growth bioassay showed significant increases in length of fish exposed to SCL wastewater at 7 d but not at 28 or 56 d. Larvae exposed as embryos and then introduced into field mesocosms did display significant differences in dry weight. In this instance, fish exposed to wastewater were significantly larger during the laboratory portion of the test (initial), but after 21 d in a field mesocosm (final), they were similar in size or smaller than fish growing in nonprocessed water.
Development of sediment toxicity test with tropical peneid shrimps
Authors: Moraes Rosane B C , Pfeiffer Wolfgang C , Guimarães Jean R D , Borges Alexandre Luiz N. , Campos Alexandre N 
Published: March 2010

Abstract
A methodology to test the toxicity of marine and estuarine sediments was developed using postlarval organisms of the marine shrimp Penaeus schmitti and P. paulensis. The tests were conducted in aquariums with a water feedback system and a sediment layer of 2 cm. The postlarvae exposure time to the sediments was 10, 28, and 52 d. The tested sediments were collected in contaminated sites of Guanabara and Sepetiba Bays and at the reference site of Ilha Grande inlet in Rio de Janerio, Brazil. The toxicity of the sediments was evidenced with exposures of 28 d or longer. The sediment from Saco do Engenho (Sepetiba Bay) was the most toxic, affecting the survival of both P. schmitti and P. paulensis. The sediment from Guanabara Bay was toxic to P. schmitti, affecting its survival after 28 d of exposure.
Kinetic analysis of zinc accumulation in the gills of juvenile rainbow trout: Effects of zinc acclimation and implications for biotic ligand modeling
Authors: Alsop Derek H , Wood Chris M 
Published: March 2010

Abstract
Juvenile rainbow trout were acclimated to hard water (Ca2+ = 1.0 mM, Mg2+ = 0.2 mM; hardness = 120 mg CaCO3/L) and hard water plus 250 μg/L Zn (3.8 μM). After 30 d of exposure, there was no difference in the total Zn levels of the gills of Zn-exposed and control fish (˜70 μg Zn/g gill). Exposure of both groups to a range of Zn concentrations (0–2,900 μg/L Zn) for up to 7 d also had no effect on the measured total Zn levels in the gills. However, using radiolabeled 65Zn, measurement of new Zn appearance in the gills was possible. Trout were exposed to a range of Zn concentrations (with 65Zn) and the gills were sampled at times ranging from 0.5 to 72 h. The fast turnover pool of Zn in the gills increased with increasing acute Zn exposure concentration, while the maximum size of the fast pool was about ninefold larger in Zn-acclimated fish (4.14 μg Zn/g gill) versus control fish (0.45 μg Zn/g gill). At all sampling times, gill 65Zn accumulation exhibited saturation kinetics, allowing calculation of binding capacity (Bmax) and affinity (Kd). In both control and Zn-acclimated trout, Kd decreased rapidly (affinity increased) from 0.5 to 3 h and then remained constant up to 72 h. Bmax increased rapidly from 0.5 to 3 h in both groups, then the rate of increase began to subside but was still increasing from 24 to 72 h. At all times, the Kd of Zn-acclimated fish was higher (i.e., lower affinity) and Bmax was greater than controls. The stabilized Kds (&gt;3 h) were approximately 280 μg/L total Zn (log K = 5.6 as Zn2+) and 575 μg/L total Zn (log K = 5.3 as Zn2+) in control and Zn-acclimated fish, respectively. The Bmax of control fish at 0.5 h was 0.37 μg Zn/g gill and increased to 8.63 μg Zn/g gill by 72 h. The Bmax of Zn-acclimated fish increased from 0.70 to 11.61 μg Zn/g gill over the same time period. Preexposure to 250 μg/L Zn appeared to have little effect on acute zinc toxicity, though the 96-h LC50s for both groups were relatively high (˜3,000 μg/L Zn) in comparison to previous measurements. The relationship between gill binding constants for different metals and relative toxicity is critically assessed with respect to biotic ligand modeling.
Acute toxicity data: A comprehensive comparison of results of fish, daphnia, and algae tests with new substances notified in the European Union
Authors: Weyers Arnd , Sokull-Klüttgen Birgit , Baraibar-Fentanes Joaquin , Vollmer Gerald 
Published: March 2010

Abstract
Acute toxicity data from the New Chemicals Database of the European Chemicals Bureau were compared for fish, Daphnia, and algae. The algal growth inhibition test was the most sensitive. Correlation between fish and Daphnia toxicity values was better than the correlation with algae. Toxicity values among the three organisms correlated more strongly than any with log Pow.
Evaluation of methods to remove ammonia interference in marine sediment toxicity tests
Authors: Ferretti James A , Calesso Diane F , Hermon Tonia R 
Published: March 2010

AbstractAmmonia naturally accumulates to high concentrations in nonsurficial marine sediments. It can also interfere and confound interpretation of toxicity from persistent anthropogenic chemicals in tests with laboratory amphipods. Renewal of overlying water has become a standardized procedure to decrease pore-water ammonia. Our objective was to propose an alternative technique for decreasing pore-water ammonia concentrations. Sediment samples with ammonia concentrations of 70 and 155 mg/L were purged of toxic concentrations in pore-water ammonia using the existing procedure of performing two renewals of overlying water per day. A thin-layer technique, which involved increasing the sediment surface area during the purging period, decreased the ammonia concentration by as much as 4.5-fold faster than the conventional purging protocol. Minimal decreases in concentrations of polycyclic aromatic hydrocarbons, heavy metals, and total organic carbon were found among all the purging techniques. Toxicity tests with the marine amphipod Ampelisca abdita suggest that minimizing the time required to purge a sediment of ammonia is critical in maintaining the integrity of the sample. The thin-layer purging technique appears to be an effective method of decreasing pore-water ammonia concentrations in sediments before laboratory toxicity testing with amphipods.
Pesticide residues in the aquatic environment of banana plantation areas in the North Atlantic Zone of Costa Rica
Authors: Castillo Luisa E. , Ruepert Clemens , Solis Efrain 
Published: March 2010

Abstract
A study of pesticide residues in surface waters and sediments was undertaken in the Suerte River Basin, Costa Rica, that drains into the Tortuguero conservation area. Samples were collected in streams, packing plants, and the Suerte River. The most frequently measured compounds in surface water samples were the fungicides thiabendazole, propiconazole, and imazalil; the nematicides terbufos and cadusafos; and the insecticide chlorpyrifos. At the conservation area, propiconazole was detected in 43% of the samples at concentrations ranging from 0.05 to 1.0 μg/L. In 25% of the samples collected at this site, a nematicide (cadusafos, carbofuran, or ethoprophos) was detected (0.06–6.2 μg/L). According to this study, most of the insecticide-nematicides analyzed pose a risk for acute or chronic toxicity to aquatic organisms based on the exposure levels and toxicity values from the literature. Ametryn, imazalil, and thiabendazole also exceeded the calculated chronic risk ratio. The most frequently detected compounds in sediments were thiabendazole, chlorpyrifos, imazalil, and propiconazole. The occurrence was higher in the packing plants and streams. Pesticides in waters and sediments of Tortuguero conservation area could pose a threat to this wetland and an additional stress to the endangered species that inhabit this area. More information is needed regarding the distribution and stability of pesticides in the lagoon system as well as of the effects of mixtures of low levels of pesticides and their degradation products on representative species of the Tortuguero ecosystem. Meanwhile, all measures to reduce the emissions of pesticides from the banana plantations and the packing plants should be taken.
Competitive displacement reactions of cadmium, copper, and zinc added to a polluted, sulfidic estuarine sediment
Authors: Simpson Stuart L , Rosner Joanne , Ellis John 
Published: March 2010

AbstractThe competitive displacement reactions occurring after the addition of Cd, Cu, and Zn to a polluted, sulfidic estuarine sediment were studied. Pore-water metal measurements indicated that added Cd and Zn reacted quantitatively with the acid-volatile sulfide (AVS) fraction (primarily FeS) of the sediments to form CdS and ZnS, whereas Cu reacted to form Cu2S, not CuS as is often assumed. The titration of a synthetic FeS phase, with Cu(II) in a strictly oxygen-free environment was used to provide a mechanistic illustration of the formation of Cu2S involving the reduction of Cu(II) to Cu(I) by Fe(II). Although this reduction reaction is not thermodynamically favorable in acidic solutions, in near-neutral pH environments the dual precipitation of Cu2S (reduced phase) and FeOOH (oxidized phase) is the driving force for the reaction. Only when the sedimentary AVS (FeS) phase had been exhausted did the added Cu displace Zn and Cd ions from their respective binding phases. Likewise, Cd added in excess of the molar AVS (FeS) concentration displaced Zn from less stable solid phases. These observations, although commonly predicted by thermodynamics, have seldom been demonstrated in real sediments and provide evidence that AVS (FeS) is the most reactive phase in anoxic sediments. The metal additions caused large disturbances to the sediment redox potential. This was attributed to disruption of the HS-/SO 42− redox equilibrium position by precipitation of HS− as metal sulfide phases. Although these redox changes did not seem to affect the partitioning of Cd, Cu, or Zn to the reactive sulfide phase (AVS), significant changes to the pore-water metal speciation may be expected. The effects of these observations on metal bioavailability for sediment toxicology studies that utilize metal-spiked sediments during method development are discussed.
Diffusion and degradation of atrazine in a water/sediment system
Authors: Mersie Wondi , McNamee Clyde , Seybold Cathy A , Tierney Dennis P 
Published: March 2010

Abstract
This study determined the effects of temperature and residence time on diffusion and degradation of [14C]atrazine applied to the surface of sterilized and nonsterilized river water over a sediment. Water and sediment were placed in glass columns and incubated at 5 or 24°C. Samples were collected at 0, 7, 14, 28, 42, 56, and 112 d before and after disturbance. The warmer temperature (24°C) initially increased the rate of 14C distribution in the aqueous phase. Disturbance caused approximately 15% of the total 14C to be removed from the aqueous phase by sterile or unsterile sediment incubated at 5°C. At 24°C, the level of 14C in disturbed sediments incubated for more than 28 d gradually increased. This increased retention of 14C by sediment coincided with greater detection of the polar metabolite hydroxyatrazine (HA). More HA was recovered in nonsterilized than in sterilized sediments, indicating the contribution of biological processes to the production of this metabolite. In undisturbed sediments at 24°C, approximately 32% and 10% of the applied 14C permeated the top and bottom 1-cm segments, respectively. In columns incubated at 5°C, less than 5% of the 14C reached the surface of the submerged sediment. The potential impact of atrazine on biota associated with sediment would diminish with time because of dilution in the aqueous phase, transformation to HA, and bound residue formation.
Association of organotin compounds with aquatic and terrestrial humic substances
Authors: O'Loughlin Edward J , Traina Samuel J , Chin Yu-Ping 
Published: March 2010

Abstract
Organotin-humic substance (OT-HS) binding constants ( Kdoc) were determined by equilibrium-binding studies using dialysis techniques. The OT-HS binding was characterized by linear isotherms. The Kdoc values measured in this study were several orders of magnitude greater than would be predicted based only on nonpolar interactions with HS (as estimated by Kow). Binding of tri-n-butyltin (TBT) by Aldrich humic acid decreased with increasing salinity and pH, indicating that ionic interactions predominate in TBT-HS binding. Thus, the binding of OT by HS observed in this study occurs primarily through complexation, with secondary contributions from nonpolar interactions. The effects of the physicochemical properties of HS (e.g., molecular weight, % aromaticity, oxygen content) on TBT-HS binding was examined with HS from a range of sources, including a commercial humic acid and HS from aquatic and terrestrial sources. Although binding of organic contaminants by HS has been correlated with various structural features of HS, no meaningful relationship between any of the HS properties examined in this study and the extent of TBT-HS binding was found.
Differential binding of endogenous steroids and chemicals to androgen receptors in rainbow trout and goldfish
Authors: Wells Kelly , Van Der Kraak Glen 
Published: March 2010

Abstract
Androgen receptors (ARs) from fish were characterized in order to evaluate differences in the binding affinities of steroids and environmental chemicals between mammals and fish, among species offish, and among target tissues within a species of fish. High-affinity, low-capacity ARs were identified in cytosolic fractions of rainbow trout brains (Oncorhynchus mykiss) and the brains, ovaries, and testes of goldfish (Carassius auratus) using [3H]testosterone. The binding specificities of endogenous steroids to the ARs did not differ between goldfish tissues but did differ between goldfish and rainbow trout. Interspecies differences in binding specificities were also seen using cyproterone acetate, which bound to the ARs in the goldfish tissues, but not in the rainbow trout brains. The mammalian antiandrogens flutamide, vinclozolin and its metabolites 2-(((3,5)-dichlorophenyl-carbamo-yl)oxy)-2-methyl-3-butenoic acid and 3′,5′-dichloro-2-hydroxy-2-methylbut-3-enanilide, along with procymidone did not bind to the ARs in any of the fish tissues tested. However, other mammalian antiandrogens including methoxychlor and its metabolite 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane, o,p′-DDT, o,p′-dichlorodiphenyldichloroethylene (DDE) and p,p′-DDE did bind to the fish ARs, but only in the goldfish testes, demonstrating tissue differences in AR binding specificities of environmental chemicals. These results may be due to the presence of multiple AR isoforms in the different fish species and tissues. This study supports the growing evidence of species differences in the potency and actions of endocrine-disrupting chemicals and suggests that multiple species need to be tested when screening the receptor binding ability of potential endocrine-disrupting chemicals.
Implication of polymer toxicity in a municipal wastewater effluent
Authors: Rowland Carolyn D , Burton G Allen , Morrison Stephen M 
Published: March 2010

AbstractThe use of cationic polymers as flocculants and coagulant aids to control suspended solid levels in the water and wastewater treatment industry is widespread in most developed countries. Today, the most frequently used clarification polymers, polyacrylamides, are often proprietary, and little information exists on the ecological impacts of these products. Following standard U.S. Environmental Protection Agency (U.S. EPA) whole effluent toxicity testing (WET) protocols, effluent toxicity can be detected via organism response, yet methods to positively characterize cationic polymers in effluents are not provided in U.S. EPA Phase I toxicity identification evaluation (TIE) protocols. Implication of cationic polymer toxicity in a municipal wastewater effluent was achieved through a series of Ceriodaphnia dubia toxicity testing with toxicant elimination steps that included extensive effluent characterization and effluent manipulation. Key in the identification was a discrepancy in effluent toxicity with respect to the type of container in which the effluents were stored. All effluent toxicity was lost within 48 h of storage in plastic containers, while on the contrary, effluent toxicity persisted in glass-contained samples for up to 4 weeks of 4°C storage. A weight-of-evidence approach suggested that the cationic polyacrilamide polymer, Hyperfloc®, was the primary source of acute toxicity in the effluent. Removal of this polymer significantly reduced effluent toxicity. This study suggests that cationic polymer-related toxicity might not be detected if effluent samples are stored in plastic containers.
Results of an interlaboratory evaluation of an analytical screening method for assessing persistent bioaccumulative toxic chemicals in sediment samples
Authors: Silva-Wilkinson Robin A , DeGraeve G Michael , Burkhard Lawrence P , Tholen Daniel W , Sheedy Barbara R 
Published: March 2010

Abstract
An inter- and intralaboratory evaluation was performed on a recently developed sediment screening method designed to detect a wide range of persistent bioaccumulative toxins (PBTs). Ten participating laboratories analyzed sediment samples, and their results were evaluated. The analyses demonstrated that laboratories that were better prepared to perform the screening method generally characterized each of the sediment samples in a similar fashion and had 80% average interlaboratory agreement in reporting the presence or absence of chemical classes in the samples. The results of this study suggest that the sediment screening method for PBTs is reasonably reproducible when performed by properly prepared and experienced laboratories.
Environmental contaminants in Texas, USA, wetland reptiles: Evaluation using blood samples
Authors: Clark Donald R , Bickham John W , Baker Denise L , Cowman Deborah F 
Published: March 2010

Abstract
Four species of reptiles (diamondback water snake [Nerodia rhombifer], blotched water snake [N. erythrogaster], cottonmouth [Agkistrodon piscivorus], and red-eared slider [Trachemys scripta]) were collected at two contaminated and three reference sites in Texas, USA. Old River Slough has received intensive applications of agricultural chemicals since the 1950s. Municipal Lake received industrial arsenic wastes continuously from 1940 to 1993. Blood samples were analyzed for organochlorines, potentially toxic elements, genetic damage, and plasma cholinesterase (ChE). Dichlorodiphenyldichloroethylene (DDE) concentrations reached as high as 3.0 ppm (wet weight) in whole blood of a diamondback water snake at Old River Slough, a level probably roughly equivalent to the maximum concentration found in plasma of peregrine falcons (Falco peregrinus) in 1978 to 1979 when DDE peaked in this sensitive species. Possible impacts on diamondback water snakes are unknown, but at least one diamondback water snake was gravid when captured, indicating active reproduction. Arsenic was not found in red-eared sliders (only species sampled) from Municipal Lake. Red-eared sliders of both sexes at Old River Slough showed declining levels of ChE with increasing mass, suggesting a life-long decrease of ChE levels. Possible negative population consequences are unknown, but no evidence was found in body condition (mass relative to carapace length) that red-eared sliders at either contaminated site were harmed.
Biomarker response and health of polychlorinated biphenyl- and chlordane-contaminated paddlefish from the Ohio River Basin, USA
Authors: Gundersen Deke T , Miller Ruthellen , Mischler Amy , Elpers Krista , Mims Steve D , Millar Jody G , Blazer Vicki 
Published: March 2010

Abstract
Fifty paddlefish (Polyodon spathula) collected from two sites on the Ohio River and from one site on the Cumberland River, USA, were examined to determine gonad polychlorinated biphenyl (PCB) and chlordane concentrations, amounts of plasma sex steroids (testosterone and estradiol), hepatic microsomal ethoxyresorufin-O-deethylase (EROD) activity, and the presence of immunoreactive cytochrome P450 1A (CYP1A) protein. Percent hatch and liver, spleen, and kidney histology were also determined. Gonad PCB and chlordane concentrations were significantly higher in Ohio River paddlefish than in Cumberland River paddlefish. Gonad PCB and chlordane concentration and gonad percent lipid were correlated in Ohio River paddlefish. Five of 10 Ohio River egg samples exceeded the Food and Drug Administration's action limit for chlordane (0.30 μg/g). Polychlorinated biphenyl congener-specific analysis detected predominantly the tetra-, penta-, and hexachlorobiphenyls in paddlefish testes. Plasma testosterone levels were significantly lower in males collected from the upper Ohio River site than those collected from the lower part of the river. There was no measurable hepatic microsomal EROD activity in any of the 50 paddlefish collected from the three sites. Western blotting analysis confirmed that a rabbit antitrout CYP1A1 IgG antibody did not recognize a CYP1A protein in paddlefish liver microsomes. Percent hatch was not significantly different in eggs collected from the Cumberland (88–96%) and Ohio Rivers (90–95%). Histological analysis of liver, spleen, and kidney detected the presence of hepatic steatosis and hemosiderosis, splenic lymphoid cell depletion, and hyperplasia of interrenal and chromaffin tissues. Immunosuppression, hepatic metabolic disorders, and altered neuroendocrine function may be occurring in Ohio River paddlefish. Results presented here suggest that organochlorine exposure may be jeopardizing the long-term health of Ohio River paddlefish and that additional investigation of contaminant effects on immune system function and hormone levels in paddlefish is warranted.