bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of maternal exposure to tributyltin on reproduction of the pearl oyster (Pinctada fucata martensii)
Authors: Inoue Suguru , Oshima Yuji , Nagai Kiyohito , Yamamoto Takashi , Go Jyoji , Kai Norihisa , Honjo Tsuneo 
Published: November 2004

Abstract
We examined the effect of tributyltin (TBT) on reproduction of the pearl oyster (Pinctada fucata martensii). In a maternal exposure test, five female pearl oysters were exposed to TBT at measured concentrations of 0 (control), 0.092, or 0.191 μg/L at 25°C for one week, and the embryo developmental success (the ratio of normal D-larvae to all larvae) was measured. The embryo developmental success was significantly decreased in the 0.191-μg/L treatment group (65.5%) compared to that in the control group (82.5%; p = 0.031). Concentrations of TBT in the ovary reached 0.088 μg/g in the 0.191-μg/L treatment group. In a waterborne exposure test, inseminated eggs were exposed to TBT at measured concentrations of 0 (control), 0.020, 0.045, 0.091, 0.192, or 0.374 μg/L for 24 h. The embryo developmental success also was significantly decreased in the 0.192-μg/L treatment group (78.3%; p = 0.020) and no development at all was observed in the 0.374-μg/L treatment group compared with that in the control group (95.4%). These results clearly demonstrate that TBT accumulating in the bodies of bivalves has the potential to inhibit reproduction.
Physical and biochemical interactions of soil fungi with asbestos fibers
Authors: Martino Elena , Cerminara S TEFANO , Prandi Laura , Fubini Bice , Perotto Silvia 
Published: November 2004

Abstract
Iron, a structural component of most asbestos, is thought to play a crucial role in asbestos toxicity. Surface iron favors fiber uptake by mammalian cells and promotes the generation of free radicals with consequent DNA and lipid damage. In some cases, chemical removal of iron from asbestos fibers has reduced several cellular responses to asbestos. Since iron represents an essential element for soil microorganisms, many of them have developed mechanisms to scavenge this element from poorly soluble forms. We have investigated the ability of some soil fungi to produce iron chelators capable of extracting iron from crocidolite (blue asbestos). Many of the species/isolates investigated could remove significant amounts of iron from crocidolite fibers, Fusarium oxysporum being the most effective. The fungal responses following exposure to asbestos fibers also have been investigated with morphological and biochemical approaches. In liquid cultures, the fibers were visibly cleared from the suspension because they were tightly bound to the fungal hyphae. Modifications in the fungal protein profiles were observed following exposure to asbestos fibers. By binding the fibers and depriving them of iron, selected species/strains of soil fungi might represent interesting tools for the bioremediation of asbestos-contaminated soils.
Developmental toxicity of p,p′-dichlorodiphenyltrichloroethane, 2,4,6-trinitrotoluene, their metabolites, and benzo[a]pyrene in Xenopus laevis embryos
Authors: Saka Masahiro 
Published: November 2004

Abstract
Since 1995, high incidences of deformed frogs have been documented in Kitakyushu, Japan. In this area, relatively high concentrations of DDT, trinitrotoluene (TNT), their metabolites (p,p′-dichlorodiphenyldichloroethylene [DDE], p,p′-dichlorodiphenyldichloroethane [DDD], 2-amino-4,6-dinitrotoluene [2ADNT], and 4-amino-2,6-dinitrotoluene [4ADNT]), and benzo[a]pyrene [BaP]) have been identified from field samples. I used a standardized assay with Xenopus laevis embryos (frog embryo teratogenesis assay—Xenopus, FETAX) to examine the developmental toxicity of these compounds. Both DDE and BaP were considered nearly nontoxic in embryonic development because they induced low (&lt;10%) mortality and malformation incidence even at the highest concentrations tested (DDE, 393 μM; BaP, 13.2 μM). The DDD (96-h median lethal concentration [LC50] = 44.1 μM, 96-h median effective concentration [EC50] for malformation = 14.9 μM) was more lethal and teratogenic than its parent compound, DDT (96-h LC50 = 101 μM, 96-h EC50 = 41.5 μM). Predominant symptoms observed were axial malformations (DDT and DDD) and irregular gut coiling (DDT). However, DDT and DDD should not act as major lethal or teratogenic toxicants in the aquatic environment within a short-term exposure via water because their 96-h LC50 and 96-h EC50 values were extremely high, considering their low solubility in water. The TNT (96-h LC50 = 16.7 μM) was more lethal than 2ADNT (96-h LC50 = 166 μM) or 4ADNT (96-h LC50 = 115 μM). Although 4ADNT (96-h EC50 = 85.8 μM) induced various tadpole malformations, it was a weak teratogen compared with TNT (96-h EC50 = 9.78 μM) and 2ADNT (96-h EC50 = 16.9 μM). The most typical malformations observed were axial malformations, eye abnormalities (TNT), edema, and irregular gut coiling (2ADNT and 4ADNT). The 96-h LC50 and 96-h EC50 values of TNT, 2ADNT, and 4ADNT were lower than their saturated concentrations in water. Therefore, these nitroaromatic compounds may show lethal or teratogenic effects on aquatic animals if their habitats are severely contaminated with TNT.
Acute and chronic toxicity of the new explosive CL-20 to the earthworm (Eisenia andrei) exposed to amended natural soils
Authors: Robidoux Pierre Yves , Sunahara Geoffrey I. , Savard Kathleen , Berthelot Yann , Dodard Sabine , Martel Majorie , Gong Ping , Hawari Jalal 
Published: November 2004

Abstract
Monocyclic nitramine explosives such as 1 3,5-trinitro-1,3,5-triazacyclohexane (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) are toxic to a number of ecological receptors, including earthworms. The polycyclic nitramine CL-20 (2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane) is a powerful explosive that may replace RDX and HMX, but its toxicity is not known. In the present study, the lethal and sublethal toxicities of CL-20 to the earthworm (Eisenia andrei) are evaluated. Two natural soils, a natural sandy forest soil (designated RacFor2002) taken in the Montreal area (QC, Canada; 20% organic carbon, pH 7.2) and a Sassafras sandy loam soil (SSL) taken on the property of U.S. Army Aberdeen Proving Ground (Edgewood, MD, USA; 0.33% organic carbon, pH 5.1), were used. Results showed that CL-20 was not lethal at concentrations of 125 mg/kg or less in the RacFor2002 soil but was lethal at concentrations of 90.7 mg/kg or greater in the SSL soil. Effects on the reproduction parameters such as a decrease in the number of juveniles after 56 d of exposure were observed at the initial CL-20 concentration of 1.6 mg/kg or greater in the RacFor2002 soil, compared to 0.2 mg/kg or greater in the SSL soil. Moreover, low concentrations of CL-20 in SSL soil (˜0.1 mg/kg; nominal concentration) were found to reduce the fertility of earthworms. Taken together, the present results show that CL-20 is a reproductive toxicant to the earthworm, with lethal effects at higher concentrations. Its toxicity can be decreased in soils favoring CL-20 adsorption (high organic carbon content).
Adsorption of polycyclic aromatic hydrocarbons at the air-water interface and its role in atmospheric deposition by fog droplets
Authors: Valsaraj Kalliat T. 
Published: November 2004

Abstract
This review addresses the significance of air-water interfacial adsorption in the fate and transport of polycyclic aromatic hydrocarbons (PAHs) in dispersed systems, such as fog droplets in the atmosphere and air bubbles in wastewater systems. The equilibrium (partition constants) and transport (mass accommodation coefficients) parameters in dispersed systems are discussed. Specific cases where the air-water interfacial adsorption makes a significant impact, such as uptake of naphthalene by fog droplets in a falling droplet reactor and of pyrene removal on air bubbles in a solvent sublation reactor, are discussed as illustrations. The consequence of the air-water interface in atmospheric wet deposition of PAHs by fog droplets is analyzed mathematically.
Toxicokinetics of three polychlorinated biphenyl technical mixtures in rainbow trout (Oncorhynchus mykiss)
Authors: Buckman Andrea H. , Brown Scott B. , Hoekstra Paul F. , Fisk Aaron T. 
Published: November 2004

Abstract
Accumulation and depuration parameters of polychlorinated biphenyls (PCBs) in fish have been reported only for a few congeners. As well, there is little information on the ability of fish to biotransform PCBs. To address these issues, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to dietary concentrations of three Aroclor® mixtures (1248, 1254, 1260) in food for 30 d followed by an additional 160 d of nonspiked food at 8°C. Accumulation, depuration, and potential biotransformation of 92 PCB congeners were assessed. Half-lives (t1/2) of PCB congeners ranged from 79 to 182 d, assimilation efficiencies ranged from 40 to 50% and biomagnification factors (BMF) ranged from 2.9 to 6.9. No evidence of significant biotransformation of any PCB congeners was found. All 92 congeners fell on the same t1/2 to Kow relationship as 16 preselected PCB congeners previously shown to persist in fish and no hydroxylated PCB metabolites (OH-PCBs) were detected in the plasma after 30 d of exposure. These findings suggest that OH-PCBs observed in feral fish may be accumulated from sources other than internal metabolism of the parent congeners, at least for juvenile fish at cool temperatures. Because t1/2s in this experiment were slower than t1/2s reported in other work, water temperature also may be an important factor in determining the t1/2s of all PCB congeners in fish.
Testosterone and energy metabolism in the estuarine mysid Neomysis integer (Crustacea: Mysidacea) following exposure to endocrine disruptors
Authors: Verslycke Tim , Poelmans Sofie , De Wasch Katia , De Brabander Hubert F. , Janssen Colin R. 
Published: November 2004

Abstract
A diverse set of reference compounds suspected of having an endocrine-disrupting mode of action (i.e., testosterone, flutamide, ethinylestradiol, precocene, nonylphenol, fenoxycarb, and methoprene) were tested for acute toxicity to the estuarine mysid Neomysis integer (Crustacea: Mysidacea). Neomysis integer was very sensitive to all tested compounds, with 96-h median lethal concentrations in a narrow range between 0.32 and 1.95 mg/L. The pesticides methoprene and fenoxycarb, both synthetic insect juvenile hormone analogs, were most toxic to N. integer. In addition, the short-term sublethal effects of methoprene and nonylphenol (an estrogen agonist) on the energy and steroid metabolism of N. integer were evaluated. Both compounds significantly affected energy and testosterone metabolism of N. integer at concentrations below acute toxicity levels. Energy consumption in methoprene- and nonylphenol-exposed mysids was significantly induced at 100 μg/L, resulting in a lower cellular energy allocation in these animals. Testosterone phase I metabolism was affected at 10 μg/L, whereas glycosylation was the most important phase II pathway affected in mysids exposed to 100 μg/L of both compounds. Methoprene exposure resulted in a concentration-dependent increase in the metabolic androgenization ratio. Mysids exposed to nonylphenol at 10 μg/L had a significantly higher metabolic androgenization ratio. The present study indicates that energy and testosterone metabolism of mysids, as endpoints, are able to detect endocrine-disruptive activity of chemicals after short-term exposure to environmentally realistic levels of endocrine disruptors.
Degradation and sorption of selected organophosphate and carbamate insecticides in urban stream sediments
Authors: Bondarenko Svetlana , Gan Jianying 
Published: November 2004

Abstract
Monitorings studies show that urban surface streams in the United States are commonly contaminated with pesticides, and contamination by organophosphates and carbamates is of particular concern because of their aquatic toxicity. The degradation and sorption of four common organophosphate and carbamate insecticides were studied in urban creek sediments from southern California, USA. In sediment, malathion was quickly degraded under either aerobic or anaerobic conditions, with a half-life (t1/2) &lt;3 d. Diazinon and chlorpyrifos were moderately persistent under aerobic conditions (t1/2 = 14–24 d). However, persistence of chlorpyrifos increased significantly under anaerobic conditions, and t1/2 was prolonged to 58 to 223 d. The greatest effect of redox potential was found with carbaryl. Although rapid dissipation occurred under aerobic conditions (t1/2 = 1.8–4.9 d), carbaryl became virtually nondegradable under anaerobic conditions (t1/2 = 125–746 d). The sorption coefficient consistently increased with time for all pesticides, and chlorpyrifos displayed greater sorption potential than the other pesticides. This study indicates that pesticides in sediment may become less available with time because of increased sorption, and pesticide persistence in sediment may vary greatly among compounds and with redox conditions. Under anaerobic conditions, long persistence may occur even for nonpersistent compounds.
Effects of sedimentary sootlike materials on bioaccumulation and sorption of polychlorinated biphenyls
Authors: Jonker Michiel T. O. , Hoenderboom Annemarie M. , Koelmans Albert A. 
Published: November 2004

Abstract
Bioaccumulation of hydrophobic organic chemicals from sediments containing soot or sootlike materials has been hypothesized to be limited by strong sorption of the chemicals to the soot matrixes. To test this hypothesis, we quantified bioaccumulation of 11 polychlorinated biphenyls (PCBs) into the aquatic oligochaete Limnodrilus sp. exposed to spiked sediment with and without the sootlike materials coal and charcoal. In addition, sorption experiments with sediment containing varying amounts of coal or charcoal were performed to elucidate the accumulation mechanism. Results showed that coal and charcoal (at realistic levels of 1.5% on a dry-wt basis) reduced PCB accumulation in worms 1.2 to 8.5 times when expressed on a mass basis. Moreover, whereas bioaccumulation from pure sediment increased with molecular planarity of the PCBs (toxic potency), it decreased in case of sediments containing coal and charcoal. In contrast to this advantageous effect, it was hypothesized that coal and charcoal had an adverse influence on the habitat quality of oligochaetes: Organisms inhabiting sediment containing coal or charcoal had significantly reduced lipid contents as compared to organisms from pure sediment. Because of these reduced lipid contents, lipid-normalized PCB concentrations in worms and biota-to-sediment accumulation factors (BSAFs) for most PCBs were higher in sediments containing the sootlike materials as compared to those for reference sediment. Also, measured BSAFs for coal- and charcoal-containing sediments appeared to be much higher than estimated on the basis of equilibrium partitioning theory. Sorption experiments revealed that this was caused by much weaker sorption to the sediment-coal/charcoal mixture than calculated assuming linear additivity of sorption capacities of the distinct phases. It was hypothesized that this weaker sorption resulted from competition between PCBs and dissolved organic carbon molecules for sorption sites on coal/charcoal. This points to a sorption process that is much more complicated than generally assumed.
Importance of black carbon in distribution and bioaccumulation models of polycyclic aromatic hydrocarbons in contaminated marine sediments
Authors: Vinturella Amy E. , Burgess Robert M. , Coull Brent A. , Thompson Kimberly M. , Shine James P. 
Published: November 2004

Abstract
The roles and relative importance of nonpyrogenic organic carbon (NPOC) and black carbon (BC) as binding phases of polycyclic aromatic hydrocarbons (PAHs) were assessed by their ability to estimate pore water concentrations and biological uptake in various marine sediments. Sediment bioaccumulation tests were performed with the marine polychaete Nereis virens, using a polyethylene device to estimate pore water concentrations of PAHs. Using existing partitioning data for pyrene and phenanthrene, it was found that the traditional Equilibrium Partitioning model, which assumes all organic carbon is NPOC (EqPOC), overestimated the measured pore water concentrations in the test sediments by one to three orders of magnitude. Instead, the measured pore water concentrations were better predicted from a distribution scenario that uses both BC and NPOC (EqPNPOC,BC). When comparing actual worm body burdens of pyrene and phenanthrene with the two model estimates of worm tissue concentrations, the EqPOC model tended to overestimate actual body burdens by three orders of magnitude, while the EqPNPOC,BC model came much closer to the true body burden values. The observed distribution of PAHs in the test sediments was used to calculate BC partition coefficients for five PAHs, which were one to two orders of magnitude higher than their corresponding organic carbon–normalized distribution coefficients, or KOCs. Together, these results suggest that, in certain situations, adding black carbon to distribution models may be necessary to predict accurately the bioavailability of PAHs.
Ammonium perchlorate effects on thyroid function and growth in bobwhite quail chicks
Authors: Mcnabb F. M. ANNE , Larsen Calvert T. , Pooler Penelope S. 
Published: November 2004

Abstract
Bobwhite quail chicks were used to investigate ammonium perchlorate (AP; NH4ClO4) effects on thyroid function and growth. Beginning at 3 to 4 d posthatch, we evaluated organismal thyroid status (circulating hormones), activation of the hypo-thalamic-pituitary-thyroid axis (thyroid wt) and thyroidal hormone content over a wide range of AP concentrations (50 μg/L — 4,000 mg/L) in drinking water, for relatively short (2-week) and longer (8-week) exposures. Thyroidal thyroxine (T4) content, the most sensitive index of decreased thyroid function, decreased markedly in response to increasing perchlorate exposure. Thyroid weight and plasma T4 were less sensitive indicators and similar in their ability to detect thyroid changes. Growth measurements (body wt and skeletal growth) were very insensitive indices. Because thyroids contain large hormone stores, with low exposures or short time periods, these stores can be used to maintain circulating hormones, at least temporarily. Most depletion of thyroidal T4 occurred during the first two weeks of AP exposure. Subsequent decreases were at a slower rate presumably because thyrotropin stimulation of the thyroids at least partially compensated for some of the perchlorate effect. Additional studies of the interactions between AP concentration and exposure time are needed for understanding the complex nature of thyroid responses to perchlorate.
A phytoplankton growth assay for routine in situ environmental assessments
Authors: Moreira-Santos Matilde , Soares Amadeu M.V.M. , Ribeiro Rui 
Published: November 2004

Abstract
This study proposes an ecologically relevant and cost-effective phytoplankton growth assay for routine in situ toxicity assessments. Assay procedures were developed applying, to the extent possible, the rationale behind the design of standard algal assays. Chlorella vulgaris was selected as test species because it grows well immobilized in alginate beads and has a wide geographic distribution. The performance of the assay in a freshwater system impacted by acid mine drainage demonstrated the suitability of assay chambers and procedures. The test system, made of inexpensive materials, allowed the rapid and easy deployment of the assay. The deployment of extra chambers at reference sites provided the ability to periodically check whether algal growth had already reached recommended growth criteria (time at which the assay should end). By deploying chambers filled with control medium at all sites, temperature was identified to explain 95% of the variation in growth. By using an artificial nutrient source shown capable of promoting algal growth according to recommended standards, toxicity from the mine effluent was distinguish from in situ nutrient limitation effects. The very good agreement (r2 = 90%) between mean in situ growth rates estimated by microscopy and by spectrophotometry and their similar coefficient of variation showed the latter to be a suitable straightforward methodology for assay endpoint estimation.
Relationships among exceedences of metals criteria, the results of ambient bioassays, and community metrics in mining-impacted streams
Authors: Griffith Michael B. , Lazorchak James M. , Herlihy Alan T. 
Published: November 2004

Abstract
If bioassessments are to help diagnose the specific environmental stressors affecting streams, a better understanding is needed of the relationships between community metrics and ambient criteria or ambient bioassays. However, this relationship is not simple, because metrics assess responses at the community level of biological organization, while ambient criteria and ambient bioassays assess or are based on responses at the individual level. For metals, the relationship is further complicated by the influence of other chemical variables, such as hardness, on their bioavailability and toxicity. In 1993 and 1994, U.S. Environmental Protection Agency (U.S. EPA) conducted a Regional Environmental Monitoring and Assessment Program (REMAP) survey on wadeable streams in Colorado's (USA) Southern Rockies Ecoregion. In this ecoregion, mining over the past century has resulted in metals contamination of streams. The surveys collected data on fish and macroinvertebrate assemblages, physical habitat, and sediment and water chemistry and toxicity. These data provide a framework for assessing diagnostic community metrics for specific environmental stressors. We characterized streams as metals-affected based on exceedence of hardness-adjusted criteria for cadmium, copper, lead, and zinc in water; on water toxicity tests (48-h Pimephales promelas and Ceriodaphnia dubia survival); on exceedence of sediment threshold effect levels (TELs); or on sediment toxicity tests (7-d Hyalella azteca survival and growth). Macroinvertebrate and fish metrics were compared among affected and unaffected sites to identify metrics sensitive to metals. Several macroinvertebrate metrics, particularly richness metrics, were less in affected streams, while other metrics were not. This is a function of the sensitivity of the individual metrics to metals effects. Fish metrics were less sensitive to metals because of the low diversity of fish in these streams.