bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toxicity of trifluoroacetate to aquatic organisms
Authors: Berends Albert G , Boutonnet Jean Charles , Rooij Christ G De , Thompson Roy S 
Published: March 2010

Abstract
As a result of the atmospheric degradation of several hydrofluorocarbons and hydrochlorofluorocarbons, trifluoroacetate (TFA) will be formed. Through precipitation, TFA will enter aquatic ecosystems. To evaluate the impact on the aquatic environment, an aquatic toxicity testing program was carried out with sodium trifluoroacetate (NaTFA). During acute toxicity tests, no effects of NaTFA on water fleas (Daphnia magna) and zebra fish (Danio rerio) were found at a concentration of 1,200 mg/L. A 7-d study with duckweed (Lemna gibba G3) revealed a NOEC of 300 mg/L. On the basis of the results of five toxicity tests with Selenastrum capricornutum, we determined a NOEC of 0.12 mg/L. However, algal toxicity tests with NaTFA and Chlorella vulgaris, Scenedesmus subspicatus, Chlamydomonas reinhardtii, Dunaliella tertiolecta, Euglena gracilis, Phaeodactylum tricornutum, Navicula pelliculosa, Skeletonema costatum, Anabaena flos-aquae, and Microcystis aeruginosa resulted in EC50 values that were all higher than 100 mg/L. The toxicity of TFA to S. capricornutum could be due to metabolic defluorination to monofluoroacetate (MFA), which is known to inhibit the citric acid cycle. A toxicity test with MFA and S. capricornutum revealed it to be about three orders of magnitude more toxic than TFA. However, a bioactivation study revealed that defluorination of TFA was less than 4%. On the other hand, S. capricornutum exposed to a toxic concentration of NaTFA showed a recovery of growth when citric acid was added, suggesting that TFA (or a metabolite of TFA) interferes with the citric acid cycle. A recovery of the growth of S. capricornutum was also found when TFA was removed from the test solutions. Therefore, TFA should be considered algistatic and not algicidic for S. capricornutum. On the basis of the combined results of the laboratory tests and a previously reported semi-field study, we can consider a TFA concentration of 0.10 mg/L as safe for the aquatic ecosystem.
Implications of gut purging for tissue residues determined in bioaccumulation testing of sediment with Lumbriculus variegatus
Authors: Mount David R , Dawson Timothy D , Burkhard Lawrence P 
Published: March 2010

Abstract
Bioaccumulation test procedures using the oligochaete Lumbriculus variegatus have been developed as a means of evaluating the accumulation of chemicals from freshwater sediments. To avoid including chemicals associated with gut contents as part of the measured tissue residue, a 24-h period of purging in clean water after the uptake phase of the test has been recommended. While purging acts to reduce bias from gut contents, it also has the potential to introduce bias caused by depuration of chemicals from tissues. In this paper, a series of model calculations are used to assess the expected sensitivity of measured residues of nonionic organic chemicals to the presence of sediment in the gut and to varying lengths of purging. If organisms are not purged, the predicted influence of gut contents on measured residue is not large (generally &lt;20%) when a biota-sediment accumulation factor (BSAF) of one is assumed. However, if BSAFs substantially less than one apply, projected errors increase to 30-fold or more. To derive a better estimate of the time required for L. variegatus to clear the gut of sediment, a sediment purging experiment was conducted; results indicate that &gt;98% of sediment had cleared the gut in 6 h (half-life = 0.98 h). Based on these results and model analyses, a much shorter purging period of 6 h, rather than 24 h, is suggested as a reasonable guideline for many test applications.
Facilitated transport in European soils from the Euro-soil project
Authors: Dolfing Jan , Scheltens Stieneke D 
Published: March 2010

Abstract
We studied the response of five reference soils from the European Union (a vertic cambisol, rendzina, dystric cambisol, orthic luvisol, and orthic podzol, also known as Euro-soils 1 to 5) to the addition of HCl and NaOH. For all soils, which were incubated as soil slurries, the amount of organic carbon in solution remained essentially constant upon addition of HCl but increased upon addition of NaOH; that is, it was not the pH of the soil that determined changes in the solubilization of dissolved organic carbon but ΔpH. This observation has implications for the design of active soil management strategies, because increased amounts of dissolved organic carbon in the soil solution pose a risk for leaching of contaminants to deeper soil layers and eventually to the groundwater. In the past, much attention has been paid to the reaction of soils to acidification and changing land use as practiced when agricultural land is taken out of production. The observations reported here indicate that soil alkalization is not necessarily without environmental and toxicological risks.
Reproductive ecology of tree swallows (Tachycineta bicolor) with high levels of polychlorinated biphenyl contamination
Authors: McCarty John P , Secord Anne L 
Published: March 2010

AbstractTree swallows (Tachycineta bicolor) breeding along the Hudson River forage extensively on PCB-contaminated insects that emerge from the river. We studied the reproductive ecology and behavior of tree swallows breeding at several sites along the Hudson River. Related work has shown that PCB levels in both eggs and chicks were among the highest ever reported in this species, with concentrations comparable to those found in aquatic organisms in the Hudson River. In 1994, reproductive success at PCB-contaminated sites was significantly impaired relative to other sites in New York. Reduced reproductive success was largely due to high levels of nest abandonment during incubation and reduced hatchability of eggs. In 1995, reproductive output was normal, but higher than expected rates of abandonment and supernormal clutches persisted. Growth and development of nestlings was not significantly impaired. Given the levels of contamination in this population, the success of most Hudson River tree swallows reinforces the importance of understanding interspecific differences in the effects of contaminants.
Individual and demographic responses of the gray-tailed vole to vinclozolin
Authors: Caslin Tracie M , Wolff Jerry O 
Published: March 2010

Abstract
We tested the hypothesis that vinclozolin, a fungicide that has been demonstrated in the laboratory to disrupt hormonal activity of rats and mice, would have adverse effects on a field population of voles. We conducted two field experiments to determine whether exposure to vinclozolin following a standard application rate of Curalanr̀ fungicide had adverse effects on the reproductive development and demography of the gray-tailed vole, Microtus canicaudus. In one experiment conducted during the rainy season, mean lengths of testes and seminal vesicles were smaller (p ≤ 0.08), levels of plasma testosterone were lower (p = 0.025), and proportion of pregnant females was lower (p = 0.05) in treatment than in control animals; however, this difference was not sufficient to affect juvenile recruitment, sex ratio, or population growth. In a second experiment conducted under drier conditions, no differences occurred in measurements of reproductive organs or demography of treatment and control populations. The results suggest that precipitation may have increased the potency of the chemical by washing it down to ground level and (or) by increasing the uptake of toxic metabolites by the plants, resulting in greater dietary exposure to the voles. Although our results revealed no biologically significant effects of vinclozolin at the population level under the conditions of our experiments, they do suggest that multiple applications or a higher application rate of a vinclozolin product may have negative effects on male reproductive development and demography in wild populations.
Ecotoxicological and analytical assessment of hydrocarbon-contaminated soils and application to ecological risk assessment
Authors: Saterbak Ann , Toy Robin J , Wong Diana C L , McMain Bruce J , Williams M Patty , Dorn Philip B , Brzuzy Louis P , Chai Eric Y , Salanitro Joseph P 
Published: March 2010

Abstract
Ecotoxicological assessments of contaminated soil aim to understand the effect of introduced chemicals on the soil flora and fauna. Ecotoxicity test methods were developed and conducted on hydrocarbon-contaminated soils (&lt;5,000–30,000 mg/kg total petroleum hydrocarbon) and on adjacent uncontaminated control soils from eight field locations. Tests included 7-d, 14-d, and chronic survival tests and reproduction assays for the earthworm (Eisenia fetida) and seed germination, root length, and plant growth assays for corn, lettuce, mustard, and wheat. Species-specific responses were observed with no-observed effect concentrations (NOECs) ranging from &lt;1 to 100% contaminated soil. The 14-d earthworm survival NOEC was equal to or greater than the reproduction NOEC values for numbers of cocoons and juveniles, which were similar to one another. Cocoon and juvenile production varied among the control soils. Germination and root length NOECs for mustard and lettuce were less than NOECs for corn and wheat. Root length NOECs were similar to or less than seed germination NOECs. Statistically significant correlations (p &lt; 0.05) for earthworm survival and seed germination as a function of hydrocarbon measurements were found. The 14-d earthworm survival and the seed germination tests are recommended for use in the context of a risk-based framework for the ecological assessment of contaminated sites.
Two-region linear/nonlinear sorption modeling: Batch and column experiments
Authors: Young Dirk F , Ball William P 
Published: March 2010

AbstractBatch and column experiments were conducted to assist in elucidation of the mechanism and rates of slow diffusion of 1,2,4-trichlorobenzene into Borden sand. Batch rate experiments were conducted at three concentration levels, and a full isotherm was developed over 550 d. The equilibrium isotherm showed significant nonlinearity (Freundlich exponent = 0.75). Three column experiments were conducted—two at low velocity (each at a different input concentration) and one at high velocity. The data were analyzed with four different models; the two most successful are described in detail here. These two models divided sorption between instantaneously equilibrating and diffusion-limited domains, with either a linear or nonlinear sorption isotherm assumed for the instantaneously equilibrating fraction of sorption sites. Either model could simulate any single data set by adjustment of two parameters; however, no single parameter set could simulate all data sets. The model with a linearly sorbing instantaneous fraction described the batch data better than the model with a nonlinearly sorbing instantaneous fraction; however, a nonlinearly sorbing instantaneous fraction described the slow column experiments much better than a linearly sorbing instantaneous fraction. The high-flow-rate column experiment indicated that the assumed instantaneous fraction is actually influenced by rate limitations, suggesting that more complex models are needed in order to simulate this shorter time scale behavior. Overall, our work illustrates how one needs to include a wide variety of experimental conditions in order to fully test the complex set of sorption equilibrium and rate mechanisms that are present in natural solids.
Survey of estrogenic activity in United Kingdom estuarine and coastal waters and its effects on gonadal development of the flounder Platichthys flesus
Authors: Allen Yvonne , Scott Alexander P , Matthiessen Peter , Haworth Sarah , Thain John E , Feist Steve 
Published: March 2010

Abstract
Estrogenic discharges are known or suspected to be present in many United Kingdom estuaries and are also occurring from offshore oil and gas installations. The aim of this study was to establish whether estrogens and their mimics are present in marine waters at concentrations that can produce biological responses in fish and, if so, to discover whether the effects are likely to be harmful to populations and communities through changes in reproductive and other physiological processes. Laboratory studies and extensive field surveys were carried out with the euryhaline flounder (Platichthys flesus), using the amount of yolk protein vitellogenin in the blood of free-living male fish as an indicator of exposure to estrogens. Exposure to the synthetic estrogen ethynylestradiol for 3 weeks confirmed that the vitellogenin response was made and showed that this species is about one order of magnitude less sensitive than the freshwater species rainbow trout. The fish did not respond to the estrogen mimic nonylphenol at concentrations of 30 μg/L. Wild male flounder were sampled from four contaminated United Kingdom estuaries: the Tyne, Crouch, Thames, and Mersey. Fish from one or more sites in each estuary had significantly elevated concentrations of vitellogenin in their blood when compared to concentrations in fish from the clean control estuary (Alde River). Vitellogenin concentrations in the Tyne and Mersey fish were four and six orders of magnitude greater, respectively, than control concentrations. Elevated vitellogenin concentrations were also seen in some male flounder caught in coastal areas. Approximately 20% of male fish from the Mersey estuary contained oocytes in their testes, but this intersex condition was not seen elsewhere. The implications of these findings for fish populations are discussed.
Organic chloramines in disinfected wastewaters: Rates of reduction by sulfite and toxicity
Authors: Jameel Rubina H , Helz George R 
Published: March 2010

Abstract
Peptides and protein fragments that have been monochlorinated at terminal amino-N sites are known to react sluggishly with S(IV) dechlorinating agents in wastewater treatment plants. Persistence of these chloramines may imperil downstream aquatic organisms. Reactivity of sidechain amino-N is explored in this paper, and previous kinetic information on chloramine reduction by S(IV) is summarized. Much like other chloramines, side-chain chlorinated N-chloroacetyllysine reacts with SO1/2- in borate buffer at 25°C according to the law rate = [SO2−3 [chloramine](520[H3BO3] + 5.7 × 1010[H3O+] + 4.1) (time in s, concentration in M). Apparently because of their greater basicity, aliphatic monochloramines such as Nchloroacetyllysine are reduced rapidly at near-neutral pH, in contrast to terminally chlorinated peptides. At pH &gt; 10, all monochloramines will be reduced at nearly the same, quite slow rate (t1/2 ≈ 0.1/[SO2−3]; time in s, SO2−3 in M). Microtox™ (Azur Environmental, Carlsbad, CA, USA) bioassays indicate that two terminally chlorinated N-chloropeptides as well as side-chain chlorinated N-chloroacetyllysine are much less toxic to Vibrio fisheri than NH2Cl, N-chloroglycine, and N-chloropiperidine. An astonishingly simple relationship describes the bioassay results at 5 min exposure as In(EC50) = −3.684 + 0.0221 (MW) (EC50 in mg/L as C12; molecular weight [MW] in Daltons). These exploratory data offer a basis for optimism that S(IV)-surviving N-chloropeptides will prove less toxic in natural ecosystems than rapidly reduced chloramines, but further investigations are needed.
Applicability of Tedlar™ bags to aqueous sampling for ambient toxicity testing: Adsorption of trace metals
Authors: deBruyn Adrian M H , Rasmussen Joseph B 
Published: March 2010

Abstract
Many materials commonly used to collect and store samples for ambient toxicity testing will readily sorb and/or leach contaminants. Previous work indicates that Tedlar™ (polyvinylfluoride) sampling bags are largely inert toward organics; we report here that this material is similarly inert to Co2+, Cu2+, Zn2+, Sb3+, Pb2+, and Cd2+ in neutral solution. We found no trace metal adsorption at low pH and only slight adsorption (mean loss = 2.1 ppb) at neutral pH from 100-ppb solutions held in Tedlar bags for 24 h.
Subcellular distribution and translocation of radionuclides in plants
Authors: Gouthu Satyanarayana , Weginwar Rajiv , Arie Tsutomu , Ambe Shizuko , Ozaki Takuo , Enomoto Shuichi , Ambe Fumitoshi , Yamaguchi Isamu 
Published: March 2010

Abstract
The subcellular distribution of radionuclides in Glycine max Merr. (soybean) and Cucumis sativus L. (cucumber) and translocation of plant absorbed radionuclides with growth in soybean were studied. More than 60% of cellular incorporated Rb, Sr, Mn, Co, Nb, and Se remained in the supernatant fraction; 55% and 20% of Cr was bound to soybean and cucumber cell wall fractions, respectively; 70% or more of Be, Y, and Fe was fixed in the chloroplast fraction; and approx. 10% of Sc, Fe, V, and As were fixed in the mitochondrial fraction. Translocation of nuclides within the soybean plant at different stages of growth has been determined. Vanadium, Y, Be, Se, Nb, Sc, Cr, and Zr were predominantly accumulated in the root. Although the total percentage of plant uptake of Sc, Zr, Nb, and Cr was high, because of low mobility and translocation to shoot, their accumulation in the fruit fraction was negligible. The translocation of mobile nuclides in plants was demonstrated clearly by Rb, Zn, and Fe. Data on the nuclide fraction mobilized from vegetative parts into edible parts was used to assess the percentage of accumulated radionuclides in plants that may reach humans through beans.
Accumulation and effects of aluminum smelter—generated polycyclic aromatic hydrocarbons on soft—bottom invertebrates and fish
Authors: NÆae, Kristoffer , Hylland Ketil , Oug Eivind , Föourlin Lars , Ericson Gunilla 
Published: March 2010

Abstract
An integrated study involving measurements of polycyclic aromatic hydrocarbon (PAH) levels in bottom sediments, assessments of resident soft—bottom communities, the accumulation of PAHs in soft—bottom invertebrates, and biomarker responses in invertebrates and fish was conducted to assess the impact of an aluminum reduction plant in a Norwegian fjord. The fjord sediments were heavily contaminated by PAHs in the inner reaches near the aluminum smelter, where concentrations were well above levels elsewhere reported to induce biological effects. Nevertheless, the PAH contamination in the fjord did not seem to have severe effects on the benthic biota. This conclusion can be drawn from the soft—bottom communities as well as from biomarker analyses. Presumably, contaminant speciation is important for explaining the restricted biological effects. The results support the assumption that PAHs associated with soot—like structures have limited bioavailability. They also point to the need to link various single—species approaches to measurements of effects on higher levels of organization and with an understanding of the speciation of the chemical contaminant.
Field transplantation of the freshwater bivalve Corbicula fluminea along a polymetallic contamination gradient (river Lot, France): II. Metallothionein response to metal exposure
Authors: Baudrimont Magalie , Andrès Sandrine , Metivaud Jacqueline , Lapaquellerie Yvon , Ribeyre Francis , Maillet Noelle , Latouche Claude , Boudou Alain 
Published: March 2010

Abstract
Specimens of the Asiatic clam Corbicula fluminea were transplanted from a clean lacustrine site to four stations along a polymetallic pollution gradient in the river Lot, France, downstream from an old Zn ore treatment facility (see Part I). From April to September 1996, we studied Cd and Zn bioaccumulation and the metallothionein-like metal-binding protein (MT) concentrations by subsampling the cages at t = 0, 21, 49, 85, 120, and 150 d. Marked differences were observed among the four stations. At the most polluted station Riou-Mort, MT concentrations did not increase despite very rapid metal accumulation; all mollusks died between days 49 and 85, suggesting that the metal detoxification mechanisms were overwhelmed at this station. At the next station downstream, the final levels of bioaccumulated metal after 150 d were as high as those at the Riou-Mort station (t = 21 d), but in this case the MT concentrations also increased progressively with positive correlations between MT and metal concentrations; no mortality was observed, but a significant growth inhibition was revealed in comparison to the reference site, with a lack of correlation between MT (as a stress response) and reduced growth. Subcellular metal partitioning, as determined by size-exclusion chromatography, revealed that most of the Cd was sequestered by MT (70% of cytosolic Cd). In contrast, most of the Zn was bound to low molecular weight proteins (70%, ≤ 6.5 kD), the MT fraction representing only 12% of cytosolic Zn. These data show the marked role of MT toward Cd bioaccumulation and toxic effects on this freshwater bivalve species.
Biological implications of sulfide in sediment—a review focusing on sediment toxicity
Authors: Wang Feiyue , Chapman Peter M 
Published: March 2010

AbstractThe biological implications of sulfide in sediment are poorly understood and all too often ignored despite the fact that sulfide can be extremely important in determining sediment toxicity to resident biota. Sulfide influences sediment toxicity in three major ways, which are reviewed in detail: as a toxicant in its own right; by reducing metal toxicity by forming insoluble metal sulfide solids and/or by forming metal sulfide complexes; and by affecting animal behavior, which in turn can alter the toxicity of not just the sulfide but also other sediment contaminants. Our present limited understanding of sulfide in sediments represents two major problems related to determining the toxicity of sediments, both in the laboratory and the field, and the causative agents of such toxicity. First, we do not know how important sulfide toxicity is to resident populations. Second, by not adequately considering sulfide toxicity, we risk underestimating toxicity and misidentifying the causative agents. Generic and specific recommendations related to resolving these problems are provided, including appropriate measurement and monitoring of sulfide in the laboratory and the field, determination of toxicity thresholds and tolerances for a wide range of sediment-dwelling organisms, further development of toxicity identification evaluation procedures, further research into sulfide effects on metal toxicity, and determination of the influence of sulfide on bioirrigation.