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Archives of Environmental Contamination and Toxicology (v.60, #1)
Environmental Factors Affecting Ultraviolet Photodegradation Rates and Estrogenicity of Estrone and Ethinylestradiol in Natural Waters by Susanna K. Atkinson; Vicki L. Marlatt; Lynda E. Kimpe; David R. S. Lean; Vance L. Trudeau; Jules M. Blais (pp. 1-7).
The environmental fate and persistence of steroidal estrogens is influenced by their photodegradation. This can potentially occur both in the presence of the ultraviolet (UV) portion of solar radiation and in tertiary wastewater treatment plants that use UV radiation for disinfection purposes. To determine patterns of UV photodegradation for estrone (E1) and 17α-ethinylestradiol (EE2), water samples containing these compounds were exposed to levels of UVB radiation that would simulate exposure to ambient sunlight. E1 degraded with a pseudo-first-order rate law constant that was directly proportional to UVB radiation intensity (R 2 = 0.999, P < 0.001) and inversely proportional to dissolved organic carbon (DOC) concentration (R 2 = 0.812, P = 0.037). DOC acted as a competitive inhibitor to direct photolysis of E1 by UV. In contrast to E1, EE2 was more persistent under similar UVB treatment. A reporter gene assay showed that the estrogenicity of UVB-exposed estrogens did not decrease relative to non-UVB-exposed estrogens, suggesting that some of the photoproducts may also have estrogenic potency. These results show that environmental degradation rates of steroidal estrogens are predictable from the UV intensity reaching surface waters, and the DOC concentrations in these surface waters.
Assessment of Geochemical Mobility of Metals in Surface Sediments of the Santa Rosalia Mining Region, Western Gulf of California by Evgueni Shumilin; Vyacheslav Gordeev; Griselda Rodríguez Figueroa; Liudmila Demina; Konstantin Choumiline (pp. 8-25).
To asses the geomobility of cadmium, copper, iron, manganese, nickel, lead, and zinc in marine sediments near the Santa Rosalía copper smelter, which is located on the eastern coast of the Baja California Peninsula, sequential leaching was applied to sediment samples containing different levels of Cu: (1) uncontaminated or slightly contaminated (<55 mg kg−1 Cu); (2) moderately contaminated (55–500 mg kg−1 Cu); and (3) heavily contaminated (>500 mg kg−1 Cu). Concentrations of Cd, Cu, Fe, Mn, Ni, Pb, and Zn in four fractions of the leachate (mobile fraction F1, relatively mobile fraction F2, associated with organic matter/sulphides fraction F3, and residual fraction F4) were measured by atomic absorption spectrophotometry (AAS). The sediments with Cu concentration <500 mg kg−1 displayed prevalence of mobile acid-leachable fraction F1 and reducible fraction F2 for Cd, Cu, Mn, and Pb, whereas the relative contribution of fraction F3 was relatively low for all of the examined metals. Residual fraction F4 was highest (>65%) for Fe and Ni because both metals are associated with the crystalline matrix of natural sediments. The sediments heavily contaminated with Cu (>500 mg kg−1) had dramatically increased percentages of Cu, Mn, Pb, and Zn, ranging on average from 63 to 81%, in the residual fraction. In the case of Cu, for example, the relative abundances of this element in the different fractions of such sediments followed this sequence: residual fraction F4 (76 ± 5%) >absorbed form and carbonates fraction F1 (15 ± 5%) >Fe and Mn oxyhydroxides fraction F2 (5 ± 2%) >fraction associated with organic matter and sulphides F3 (4.5 ± 3.9%). Copper, Pb, and Zn contents in each geochemical fraction of all samples were compared with sediment-quality guideline values (“effects range low” [ERL] and “effects range medium” [ERM]) to assess their possible negative effects on biota. Copper contents in mobile fractions F1 and F2, which were moderately contaminated with Cu, were higher than ERL but lower than ERM guideline values. For heavily contaminated sediments, Zn contents of mobile fractions F1 and F2 were higher than ERL but lower than ERM guideline values. The Cu content of fraction F1 was higher than ERM guideline values, whereas for fractions F2 and F3 copper content was higher than ERL guidelines but still lower than ERM guideline values.
Mercury Accumulation in Sediment Cores from Three Washington State Lakes: Evidence for Local Deposition from a Coal-Fired Power Plant by Chad V. Furl; Callie A. Meredith (pp. 26-33).
Mercury accumulation rates measured in age-dated sediment cores were compared at three Washington state lakes. Offutt Lake and Lake St. Clair are located immediately downwind (18 and 28 km, respectively) of a coal-fired power plant and Lake Sammamish is located outside of the immediate area of the plant (110 km). The sites immediately downwind of the power plant were expected to receive increased mercury deposition from particulate and reactive mercury not deposited at Lake Sammamish. Mercury accumulation in cores was corrected for variable sedimentation, background, and sediment focusing to estimate the anthropogenic contribution (HgA,F). Results indicated lakes immediately downwind of the power plant contained elevated HgA,F levels with respect to the reference lake. Estimated fluxes to Lake Sammamish were compared to measured values from a nearby mercury wet deposition collector to gauge the efficacy of the core deconstruction techniques. Total deposition calculated through the sediment core (20.7 μg/m2/year) fell just outside of the upper estimate (18.9 μg/m2/year) of total deposition approximated from the wet deposition collector.
Effects of Monosulfuron on Growth, Photosynthesis, and Nitrogenase Activity of Three Nitrogen-Fixing Cyanobacteria by Jianying Shen; Wei Luo (pp. 34-43).
Application of monosulfuron, a new sulfonylurea herbicide, produced a simulative effect on heterocyst formation and nitrogenase activity but an inhibitory effect on photosynthesis, i.e., a lower net photosynthetic rate, fewer photosynthetic pigments, and a smaller Fv/Fm ratio at increasingly higher monosulfuron concentrations (0.001–10 mg/l) for three nonspecific filamentous nitrogen-fixing cyanobacteria: Anabaena azollae, A. flos-aquae, and A. azotica. The decrease in biliprotein of algal cells was less than that of carotenoid and chlorophyll-a. Monosulfuron was more readily degraded and less accumulated in A. azotica compared with A. azollae and A. flos-aquae. The three algae exhibited varying degrees of sensitivity to monosulfuron: Calculated 50% inhibition concentrations (IC50s) of algal growth and no observed-effect concentration (NOEC) values after 4 days of treatment were 0.014 and 0.005, 0.029 and 0.019, and 0.22 and 0.075 mg/l for A. flos-aquae, A. azollae, and A. azotica, respectively. Normal agricultural use of monosulfuron at postemergence rates of 0.3–0.8 mg/l in rice fields will likely be toxic to these three ubiquitous nitrogen-fixing cyanobacteria. Low-dose monosulfuron application (<0.1 mg/l) enables growth of the more tolerant A. azotica as biofertilizer, and the use of photosynthetic efficiency and growth rates as sensitive-indicator indexes of toxicity to nitrogen-fixing cyanobacteria are recommended.
Construction of River Model Biofilm for Assessing Pesticide Effects by Shohei Hayashi; Ji Eun Jang; Kazuhito Itoh; Kousuke Suyama; Hiroki Yamamoto (pp. 44-56).
Due to the high importance of biofilms on river ecosystems, assessment of pesticides’ adverse effects is necessary but is impaired by high variability and poor reproducibility of both natural biofilms and those developed in the laboratory. We constructed a model biofilm to evaluate the effects of pesticides, consisting in cultured microbial strains, Pedobacter sp. 7-11, Aquaspirillum sp. T-5, Stenotrophomonas sp. 3-7, Achnanthes minutissima N71, Nitzschia palea N489, and/or Cyclotella meneghiniana N803. Microbial cell numbers, esterase activity, chlorophyll-a content, and the community structure of the model biofilm were examined and found to be useful as biological factors for evaluating the pesticide effects. The model biofilm was formed through the cooperative interaction of bacteria and diatoms, and a preliminary experiment using the herbicide atrazine, which inhibits diatom growth, indicated that the adverse effect on diatoms inhibited indirectly the bacterial growth and activity and, thus, the formation of the model biofilm. Toxicological tests using model biofilms could be useful for evaluating the pesticide effects and complementary to studies on actual river biofilms.
Sediment Toxicity in Mid-Continent Great Rivers (USA) by Herman J. Haring; Karen A. Blocksom; Mark E. Smith; Theodore Angradi; Melissa C. Wratschko; Brandon Armstrong; David Bolgrien; James M. Lazorchak (pp. 57-67).
As part of the Environmental Monitoring and Assessment Program for Great River Ecosystems (EMAP-GRE), sediment samples were collected from 447 randomly selected littoral sites along the main channels of the Ohio, Missouri, and Upper Mississippi Rivers between 2004 and 2006. Toxicity of these sediment samples was measured using a 7-day Hyalella azteca survival and growth test. Sixty-five sites (14.5%) exhibited lethal toxicity, and 130 sites (29.1%) exhibited decreased growth. In the EMAP-GRE probabilistic sampling design, each sampled site had a weight associated with it that determined the length (and proportion) of the river represented by that sample point in the population. Weighted whole-river estimates indicated that of the 4721 river km sampled, sediment from 15.9 ± 3.0% of the river (752 ± 50 km) were lethally toxic, 27.4 ± 3.5% (1289 ± 57 km) were toxic by way of growth inhibition, and 40.0 ± 3.7% (1887 ± 68 km) exhibited either lethal or growth toxicity. Selected toxic samples were analyzed for 21 pesticides, 20 polychlorinated biphenyl congeners, and 6 polybrominated diphenyl ether congeners. For all of the samples tested, the concentration levels of these analytes were mostly lower than known toxicity thresholds, and neither unionized ammonia concentration nor osmotic stress (as measured by conductivity) could account for the toxicity found in sediments. The spatial pattern of sediment toxicity cannot be readily explained by urbanization or agricultural land use at the subcatchment scale. We speculate that the distribution of toxic sediment is more likely due to a combination of localized sources, including polluted tributaries, and the redistribution of contaminated sediments from upriver. The sediment toxicity results from this study will be used, in combination with other sediment, biologic, and habitat metrics and indicators collected in the EMAP-GRE study, to help interpret and assess the condition of the Ohio, Upper Mississippi, and Missouri Rivers.
Protective Response of 28-Homobrassinolide in Cultivars of Triticum aestivum with Different Levels of Nickel by Mohammad Yusuf; Qazi Fariduddin; Shamsul Hayat; Syed Aiman Hasan; Aqil Ahmad (pp. 68-76).
Seeds of five wheat (Triticum aestivum) cultivars (PBW-373, UP-2338, DL-LOK-01, DL-373, and HD-2338) were sown in earthen pots and 10-day-old seedlings were exposed to 0, 50, and 100 μM of nickel (Ni) in the form of nickel chloride. At the 20-day stage, seedlings were sprayed with 0.01 μM of 28-homobrassinolide (HBL). The results of the experiment at the 30-day stage revealed a decline in the dry mass per plant, leaf area, leaf water potential, and net photosynthetic rate with concomitant decline in the activities of various enzymes (viz. carbonic anhydrase and nitrate reductase) with an increasing concentration of Ni. However, an increase in proline content and the activities of catalase, peroxidase, and superoxide dismutase was observed as a result of an increase in Ni concentration. Moreover, the treatment of these stressed plants with HBL enhanced the activities of carbonic anhydrase and nitrate reductase, catalase, peroxidase, and superoxide dismutase. The proline content in the leaves also increased, which is known to act as an osmolyte and reactive oxygen species scavenger. The toxic effects generated by Ni were ameliorated by HBL through an improved antioxidant system and osmolyte. Moreover, improvement of photosynthetic parameters and growth characteristics further strengthen our belief that HBL acted as a potent stress alleviator.
Effects of the Veterinary Pharmaceutical Ivermectin in Indoor Aquatic Microcosms by Harry Boonstra; Erik P. Reichman; Paul J. van den Brink (pp. 77-89).
The effects of the parasiticide ivermectin were assessed in plankton-dominated indoor microcosms. Ivermectin was applied once at concentrations of 30, 100, 300, 1000, 3000, and 10,000 ng/l. The half-life (dissipation time 50%; DT50) of ivermectin in the water phase ranged from 1.1 to 8.3 days. The lowest NOECcommunity that could be derived on an isolated sampling from the microcosm study by means of multivariate techniques was 100 ng/l. The most sensitive species in the microcosm study were the cladocerans Ceriodaphnia sp. (no observed effect concentration, NOEC = 30 ng/l) and Chydorus sphaericus (NOEC = 100 ng/l). The amphipod Gammarus pulex was less sensitive to ivermectin, showing consistent statistically significant reductions at the 1000-ng/l treatment level. Copepoda taxa decreased directly after application of ivermectin in the highest treatment but had already recovered at day 20 posttreatment. Indirect effects (e.g., increase of rotifers, increased primary production) were observed at the highest treatment level starting only on day 13 of the exposure phase. Cladocera showed the highest sensitivity to ivermectin in both standard laboratory toxicity tests as well as in the microcosm study. This study demonstrates that simple plankton-dominated test systems for assessing the effects of ivermectin can produce results similar to those obtained with large complex outdoor systems.
Alteration of Heart Tissue Protein Profiles in Acute Cadmium-Treated Scallops Patinopecten yessoensis by Qing-Yu Huang; Cai-Wang Fang; He-Qing Huang (pp. 90-98).
Cadmium (Cd) is an extremely toxic metal that induces a wide spectrum of toxic responses in organisms in the environment. In the present study, scallops (Patinopecten yessoensis), after acclimation for 1 week in the laboratory, were subjected to acute Cd chloride (CdCl2) toxicity, and ultramorphological and proteomic changes in their heart tissues were analyzed and compared with those of the nonexposed control group. Electron microscopy showed that ultrastructures of the cytoplasm and mitochondria in scallop hearts were badly damaged, and two-dimensional gel electrophoresis showed 32 protein spots that were differentially expressed after exposure to 10 mg/l CdCl2 for 24 h. Of these spots, 8 were upregulated, 16 were downregulated, and 8 showed low expression. Proteins from these spots were identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry and database searching. The results indicated that these proteins are involved in the regulation of cell structure, transport, signal transduction, and metabolism. Among other things, four proteins―identified as amino acid adenosine triphosphate (ATP)–binding cassette transporter, glycerol-3-phosphate dehydrogenase (nicotinamide adenine dinucleotide phosphate), nicotinamide adenine dinucleotide oxidase, and ATPase―were demonstrated to be especially associated with Cd toxicity. Some of the other proteins observed in this work are of particular interest in terms of their responses to Cd, which have not been reported previously. These data may provide novel biomarkers for monitoring the Cd contamination level of flowing seawater as well as provide useful insights into the mechanisms of Cd toxicity.
Hazardous Effects of Eight Years of Application of Four Organic Waste Materials on Earthworm Numbers and Biomass in Field Lysimeters by Young Eun Na; Hea Son Bang; Soon Ik Kwon; Myung Hyun Kim; Young-Joon Ahn (pp. 99-106).
The hazardous effects on the earthworm numbers and biomass of eight consecutive yearly applications of three levels (12.5, 25, and 50 tons of dry matter/ha/y) of four different organic sludges (municipal sewage, industrial sewage, alcohol fermentation processing, and leather processing) to earthworm-free soils were examined using field lysimeters. Results were compared with those of pig manure compost (PMC)-treated soil. Of five species (Amynthas agrestis, A. sangyeoli, A. hupeiensis, Drawida koreana, and D. japonica) from 390 adult specimens collected 4 and 8 years after treatment, the number of species appeared to be lower in sludge-treated soils than in PMC-treated soils. Earthworm populations and biomass were correlated negatively with the pollution index [∑(heavy-metal concentration in soil/tolerable level)/number of heavy metal] 4 and 8 years after treatment. These results suggest that the long-term application of these sludges, particularly from industrial sewage and leather processing, might affect adversely the establishment of Megascolecid and Moniligastrid earthworms in field conditions.
Assessment of Pyrene Bioavailability in Soil by Mild Hydroxypropyl-β-Cyclodextrin Extraction by Muhammad Imran Khan; Sardar Alam Cheema; Chaofeng Shen; Congkai Zhang; Xianjin Tang; Zaffar Malik; Xincai Chen; Yingxu Chen (pp. 107-115).
Bioavailability of organic pollutants in soil is currently a much-debated issue in risk assessment of contaminated sites. Ecorisk of an organic pollutant in soil is strongly influenced by the properties of the soil and its contamination history. To evaluate the effect of aging on the availability of pyrene, earthworm (Eisenia fetida) accumulation and chemical extraction by exhaustive and nonexhaustive techniques in soil spiked with a range of pyrene levels (1.07, 9.72, 88.4, 152, and 429 μg g−1 dry soil) were measured in this study using both unaged (i.e., 0 days) and aged (i.e., 69, 150, and 222 days) soil samples. The results showed that the amount of pyrene accumulated by earthworms did not change greatly with aging time under different high-dose contamination levels, but changed significantly at lower concentrations. Moreover, aging (after 222 days) significantly decreased biological and chemical availability of pyrene. Furthermore, the relationship between earthworm bioaccumulation, hydroxypropyl-β-cyclodextrin (HPCD), and organic solvent extraction was investigated in order to find a suitable and rapid method to predict pyrene bioavailability. Results showed that, at different levels of pyrene, the mean values of earthworm uptake and HPCD extractability were 10–40% and 10–65%, respectively. Correlation (r 2 = 0.985) and extraction results for pyrene suggested that mild HPCD extraction was a better method to predict bioavailability of pyrene in soil compared with organic solvent extraction.
In Vivo and In Vitro Mixed-Function Oxygenase Activity and Vitellogenin Induction in Fish and in Fish and Rat Liver Cells by Stilbenes Isolated from Scotch Pine (Pinus sylvestris) by Joanne L. Parrott; Jagmohan Kohli; James P. Sherry; L. Mark Hewitt (pp. 116-123).
Many types of pulp and paper mill effluents have the ability to induce mixed-function oxygenase (MFO) activity and vitellogenin (VTG) protein in exposed male fish. The search for the compounds responsible for MFO induction has led to several classes of compounds, among them retene and stilbenes. The objective of this study was to investigate the biological activities of candidate stilbene compounds. Three stilbenes, 3,5-dihydroxystilbene (pinosylvin; P1), 3-hydroxy-5-methoxystilbene (P2), and 3,5-dimethoxystilbene (P3), were extracted from Scotch pine (Pinus sylvestris) and purified to evaluate their ability to induce MFO activity in vitro using ethoxyresorufin-O-deethylase (EROD) activity in a rat hepatoma cell line (H4IIE). As these compounds may be chlorinated during pulp bleaching, chlorination of P2 was undertaken, producing di- and trichlorinated isomers (Cl-P2), which were also tested. Compounds were tested for EROD-inducing ability in vivo by exposing juvenile rainbow tout (Oncorhynchus mykiss) to waterborne concentrations (0.010 to 1.0 mg/L) for 4 days. Compounds were also tested for their ability to induce VTG in trout primary liver cells in vitro. The stilbenes were weak inducers of EROD and VTG. H4IIE EROD was induced by all four compounds, with the most potent induction by P3, followed by P1, the Cl-P2 mixture, and then P2. Induction for all four stilbenes was from 3.13 × 10−3 to 3.57 × 10−4 as potent as retene and about 1.11 × 10−5 to 1.20 × 10−6 as potent as TCDD. Juvenile rainbow trout did not show EROD induction after exposures to P1, P2, or the Cl-P2 mixture, whereas P3 caused activity fourfold above that of controls. P1, P3, and Cl-P2 all weakly induced VTG in rainbow trout hepatocytes. The most potent inducer of VTG was Cl-P2, followed by P3 and P1. The results show the ability of wood-derived stilbenes to cause weak MFO induction in fish and in rat liver cells and to weakly induce vitellogenin in fish liver cells.
Mixture Toxicity Assessment of Nickel and Chlorpyrifos in the Sea Bass Dicentrarchus labrax by Mohamed Banni; Jamel Jebali; Hamadi Guerbej; Francesco Dondero; Hamadi Boussetta; Aldo Viarengo (pp. 124-131).
The present research work was designed to study Dicentrarchus labrax biotransformation and detoxification responses to acute exposure to nickel (Ni) and chlorpyrifos (CHP). Sexually immature sea bass were treated by intraperitoneal injection of nickel chloride (500 μg kg−1), chlorpyrifos (10 mg kg−1), and their binary mixture for 1, 3, and 7 days. Ni and CHP accumulation was quantified in liver after the exposure periods. The following biological responses were measured: (1) NADPH cytochrome P450 reductase (NCR) activity, as phase I biotransformation parameter; (2) gluthathione S-transferase (GST) activity as a phase II conjugation enzyme, acetylcholinesterase activity, and metallothionein (MT) content. Ni bioaccumulation in the liver resulted in an increasing uptake up to 15.48 μg g−1 wet weight (Ni-treated animals) and 16.73 μg g−1 wet weight (mixture-treated animals) after 7 days of exposure. CHP accumulation showed a distinct pattern in animals exposed to the mixture of chemicals in comparison with CHP-treated animals. NCR activity exhibited a marked activation in CHP and mixture-treated animals. GST activity was significantly increased starting from 1 day exposure in CHP-treated animals and after 3 days in Ni-treated animals. MT accumulation increased in all conditions, with a marked synergetic effect after 7 days of exposure. These data should be carefully considered in view of the biological effects of mixture pollutants, particularly in fish farming conditions.
Metal Levels in Fish Captured in Puerto Rico and Estimation of Risk from Fish Consumption by Imar Mansilla-Rivera; Carlos J. Rodríguez-Sierra (pp. 132-144).
Exposure to metals through fish consumption may represent a health risk, especially for high-fish-consumption populations such as fishing communities in the Jobos Bay and La Parguera areas in Puerto Rico. This study determined levels of As, Cd, Cu, Pb, Hg, Se, and Zn in muscle tissues of fish from the Jobos Bay and La Parguera (reference site) areas and estimated the health risk posed by fish ingestion to local fishermen and their children. Fish collected included S. cavalla (“sierra”; n = 14), M. undulatus (“roncón”; n = 21), L. synagris (“arrayado”; n = 18), and L. analis (“sama”; n = 11) in the Jobos Bay area and S. regalis (sierra; n = 10) and L. synagris (arrayado; n = 8) in La Parguera. Only As and Hg were detected at levels of human health concern. Average As and Hg levels (μg/g, wet wt) in the four species of Jobos Bay were 0.74 and 0.10 for roncón, 0.83 and 0.09 for sama, 1.00 and 0.26 for sierra, and 2.49 and 0.15 for arrayado, respectively. In La Parguera, average As and Hg levels (μg/g, wet wt) were 0.61 and 0.12 for sierra and 1.27 and 0.20 for arrayado, respectively. At both sites, the species with the highest As levels was arrayado, while for Hg, sierra obtained the highest concentrations. A risk estimation using U.S. Environmental Protection Agency standard exposure factors, and assuming that 10% of total As is the inorganic form and 100% of the total Hg is methyl Hg, predicted adverse health effects (cancer and noncancer) from fish consumption, being higher for children than for adults. However, speciation of As in fish muscle is recommended for better risk estimates. Sierra fish from Jobos Bay triggered the most restricted consumption advisories for Hg noncancer effects, where a child should not consume >1 fish meal (0.1135 kg)/month and adults should not have >3 fish meals (0.227 kg)/month. Fish consumption advisories, particularly for Hg, should be established by the local government to protect the health of susceptible populations such as children and pregnant or childbearing-age women.
Effects of Technical-Grade Active Ingredient vs. Commercial Formulation of Seven Pesticides in the Presence or Absence of UV Radiation on Survival of Green Frog Tadpoles by Holly J. Puglis; Michelle D. Boone (pp. 145-155).
Commercial formulations of pesticides contain both active and other ingredients. In some instances, the other ingredients have detrimental effects on nontarget species. Other factors such as UV radiation and predator cues have been shown to modify the toxicity of pesticides. In a laboratory study we compared the effects of technical-grade active ingredients to commercial formulations of seven common pesticides in the presence or absence of UV radiation on the survival of Rana clamitans (green frog) tadpoles over 96 h. We found a significant difference in the survival of tadpoles in technical-grade active ingredients versus commercial formulations in all of the pesticides tested. We also found that either the presence or the absence of UV radiation affected the survival of tadpoles in five of the seven pesticides tested. These results suggest that there is a need to test the effects of both active ingredients and commercial formulations of pesticides and, also, to include relevant abiotic factors like UV radiation treatments in the testing of pesticides because they can have a dramatic impact on the toxicity of some chemicals.
Concentrations of Heavy Metals in American Woodcock Harvested in Connecticut by Brian J. Hiller; John S. Barclay (pp. 156-164).
The American woodcock is an important migratory species to both consumptive and nonconsumptive users throughout the species range. Woodcock populations have been declining steadily since surveys began in 1968. Laboratory and field studies have demonstrated several adverse effects associated with metals in other species, which has led to their inclusion as potential contributing factors to the woodcock population decline. We investigated the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), and selenium (Se) in pectoral muscle (n = 100), livers (n = 108), and kidneys (n = 104) and Pb in wing bones (n = 53) from woodcock harvested in Connecticut. Cd concentrations were elevated in 99% of woodcock livers and kidneys; 30% of kidneys were above 100 μg/g dry weight, a Cd level of reported adverse tissue and reproductive effects in other species. Hg and Cr concentrations were below current biologically significant thresholds. Asc, Pb, and Se in soft tissues were associated with lead shot use in collection. Se in 24% of livers was above 10 μg/g dry weight, the reported threshold for avian health. Wing-bone Pb was elevated above 20 μg/g in 61% of adults and 23% of juveniles examined. Our findings indicate that woodcock are being exposed to potentially damaging levels of at least two metals with known effects in other species.
Dynamic Changes of Heme Oxygenase-1 in the Hippocampus of Rats After Acute Carbon Monoxide Poisoning by Li Guan; Yan-Lin Zhang; Tao Wen; Xi-Fu Wang; Ming-Xia Zhu; Jin-Yuan Zhao (pp. 165-172).
Heme oxygenase-1 (HO-1), an inducible enzyme, degrades heme to carbon monoxide (CO), iron, and bilirubin. We have investigated the relationship among HO-1 protein expression, HO activity, and CO concentrations in the hippocampus of CO-exposed rats. Western blotting and immunohistochemistry revealed that the enzyme is predominantly localized in hippocampal CA1 and CA3 pyramidal cells and in granule cells of the dentate gyrus. HO enzyme activity was reduced immediately following CO exposure, while expression of HO-1 protein was consistently upregulated in a time-dependent manner. Local CO concentrations in hippocampus rose immediately following exposure, but the elevation was maintained for ~20 h despite the decline in blood carboxyhemoglobin levels toward baseline. We suggest that CO initially inhibits HO enzyme activity, whereas at later time points the inhibition is released and local CO generation is maintained by the activity of the endogenous HO enzyme. And the noninducible form of heme oxygenase, HO-2, was not altered following CO administration. Together these results indicate that the HO/CO pathway in the rat hippocampus is induced by acute CO exposure; local CO production may play a regulatory role in brain injury following CO poisoning.
Correlational Sperm Motility Analysis: Wild Rodent Progressive Sperm Motility as a Potentially Improved Reproduction-Assessment Parameter in Mammals by Lawrence V. Tannenbaum; Robyn B. Lee (pp. 173-181).
Progressive sperm motility, describing the directed or linear movement of sperm, is infrequently reported in reproductive studies conducted with rodents. This is a curious circumstance given that progressive motility can be easily reported with current computer-assisted sperm-analysis equipment, and because progressively motile sperm seemingly display a greater likelihood of fertilizing ova than do sperm that move in a random or undefined pattern. This study presents a comparison of the routinely reported total motility (i.e., the percentage of moving sperm cells in a sample) and the progressive motility of sperm from rodents captured at soil-contaminated sites and at habitat-matched noncontaminated reference locations. Progressive motility’s trending with total motility at all areas, in terms of direction of shift, magnitude of change, and degree of correlation, was extremely high. Based on these results and in the interest of assisting ecological health assessments at contaminated sites, it would seem prudent to conduct the empirical research to determine progressive sperm motility’s threshold-for-effect, which may be lower than that for total motility.
Occurrence of Synthetic Musks in Indoor Dust from China and Implications for Human Exposure by Yan Lu; Tao Yuan; Se Hun Yun; Wenhua Wang; Kurunthachalam Kannan (pp. 182-189).
Synthetic musk compounds are used in a wide range of personal care and other consumer products. Despite this fact, few studies have reported the occurrence of synthetic musks in house dust or exposure of humans through the ingestion of indoor dust. In the present study, we determined the concentrations and profiles of two polycyclic musks (PCMs; Galaxolide® [HHCB] and Tonalide®), three nitro musks (NMs; musk ketone [MK], musk moskene [MM], and musk xylene [MX]), and one metabolite of HHCB (HHCB-lactone), in 88 indoor-dust samples from homes, dormitories, offices, and laboratories in China. In addition, we analyzed 12 dust samples collected from inside the housings of electrical/electronic devices that were located in 10 of the houses. Synthetic musks were detected in all of the dust samples analyzed, with total concentrations (sum of PCM and NM concentrations) varying from 4.42 to 688 ng g−1 (mean ± SD: 126 ± 16.2 ng g−1; median: 82.7 ng g−1). HHCB was the predominant compound in all of the dust samples analyzed accounting on average for 42.2% of the total musk concentrations. Concentrations of synthetic musks in dust samples from homes and offices were higher than the concentrations found in samples from dormitories and laboratories. Concentrations of synthetic musks in dust samples increased with the increasing number of occupants in homes. Based on the concentrations, levels of exposure to musks by way of dust ingestion were calculated to be up to 25.8 ng d−1 for adults and 138 ng d−1 for toddlers.