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| 2. |
- Ek, Helene, 1976, et al.
(författare)
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Fate and effects of 2,4,6-trinitrotoluene (TNT) from dumped ammunition in a field study with fish and invertebrates
- 2006
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Ingår i: Archives of Environmental Contamination and Toxicology. - : Springer Science and Business Media LLC. - 0090-4341 .- 1432-0703. ; 51:2, s. 244-252
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- 2,4,6-Trinitrotoluene (TNT) is the major explosive ingredient in ammunition dumped into lakes and sea after World War II. The aim of the present field study was to study the fate and effect of TNT and its degradation products from dumped ammunition. Artillery shells were cleaved longitudinally to expose TNT and placed in open boxes filled with sediment, and then placed at the sea bottom. Sediment samples were taken in each box at the start and after 3, 9, 13, 20, 24, 33, and 36 months, and the sediments were tested for toxicity with bioassays using Nitocra spinipes (96 h), Hyalella azteca (96 h), and Daphnia magna (24 and 48 h). The result from the bioassays showed no impact of dumped ammunition on the survival of H. azteca and mobility of D. magna. Bioassays with N. spinipes showed significant differences in toxicity between control boxes and boxes with shells after 9 months and thereafter. The mean mortality (+/- SD) of N. spinipes in boxes with shells was 63 +/- 22%, and the mortality in control boxes was 23 +/- 17%. No continuous increase in sediment toxicity over time was found. After 3 years, cages with European flounder (Platichtys flesus) and blue mussels (Mytilus edulis) were attached to the boxes. The fish were examined for biochemical and physiological effects 8 weeks later. Exposure to ammunition, which had rested on the sea bottom 3 years, caused no significant effects on body indices, hematological variables, and detoxification and antioxidant enzymes activities in the flounder. The sediment, bile, and blood plasma of exposed fish, and hepatopancreas of exposed mussels, contained no detectable levels of TNT and its metabolites. Only minor disappearance of TNT from the shells could be detected by visual inspection on site (by scuba divers). This study suggests that the survival of sensitive benthic organisms, e.g., N. spinipes, might be negatively affected at an ammunition dumping site.
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| 3. |
- Ek, Helene, 1976, et al.
(författare)
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Tentative biomarkers for 2,4,6-trinitrotoluene (TNT) in fish (Oncorhynchus mykiss)
- 2005
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Ingår i: Aquatic Toxicology. - : Elsevier BV. - 0166-445X .- 1879-1514. ; 72:3, s. 221-230
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Tidskriftsartikel (refereegranskat)abstract
- 2,4,6-Trinitrotoluene (TNT) is the major explosive in ammunition dumped into lakes and the sea after World War II. To identify useful biomarkers of TNT-exposure for forthcoming fish monitoring studies at ammunition dumping sites, rainbow trout (Oncorhynchus mykiss) were intraperitoneal (i.p.) injected with TNT in peanut oil at doses of 0, 100, 200 or 400 mg TNT/kg body weight and sampled 72 h later. The study covered blood parameters, and hepatic antioxidant and detoxifying enzymes. Fish treated with TNT had an increased glutathione S-transferase (GST) activity and glutathione reductase (GR) activity, and a decreased percentage of oxidised glutathione (%GSSG) compared to the control group. In addition to increased methemoglobin, the increased glutathione and glutathione dependent enzyme activities indicate that TNT oxidises macromolecules and activates antioxidant defence systems which may be useful as general biomarkers of TNT-exposure. The fish bile was analysed for TNT and its metabolites by gas chromatography-mass spectrometry (GC-MS), and the toxicity of the bile was determined with the cladoceran Ceriodaphnia dubia. A dose-dependent increase in TNT, 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT) was found in the hydrolysed bile of the TNT-treated fish. These results indicate that the fish are able to detoxify and excrete TNT and suggest that the detection of TNT, 2-ADNT and 4-ADNT in bile may be suitable as a direct marker of exposure to TNT. (c) 2005 Elsevier B.V. All rights reserved.
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| 4. |
- Ek, Helene, 1976, et al.
(författare)
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TNT leakage through sediment to water and toxicity to Nitocra spinipes
- 2007
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Ingår i: Ecotoxicology and Environmental Safety. - : Elsevier BV. - 0147-6513. ; 67:3, s. 341-348
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Tidskriftsartikel (refereegranskat)abstract
- The fate and effects of 2,4,6-trinitrotoluene (TNT) at marine ammunition dumping sites are essentially unknown. The objective of this study was to examine the release from solid TNT to seawater when covered by sediment of two different types (sandy and fine-grained) and thickness (0, 1, 2, and 4 cm), under different temperatures (5, 10, and 20 °C), and light conditions (ambient daylight and darkness) in the laboratory. The water column was analysed for TNT and some of its common transformation products, and toxicity to the copepod Nitocra spinipes after 1, 2, 4, 8, 19, and 32 weeks. Leakage of TNT to seawater and the toxicity to N. spinipes was significantly reduced by sediment burial, especially in fine-grained sediment. Hence, this study suggests that adverse effects of TNT in dumped ammunition on aquatic organisms should be delayed/reduced at low temperature and when TNT is covered sediment, especially with fine-grained sediment.
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| 5. |
- Anderbrant, O., et al.
(författare)
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Intraspecific competition affecting parents and offspring in the bark beetle Ips typographus.
- 1985
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Ingår i: Oikos. - : JSTOR. - 0030-1299. ; 45:1, s. 89-98
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Tidskriftsartikel (refereegranskat)abstract
- Parents re-emerged sooner at higher densities but the total proportion that re-emerged was independent of density. Over 20 offspring per female were produced at the lowest density (0.5/100 cm2) but only 0.6 per female at the highest density (31/100 cm2). Offspring from the lowest density were about 50% heavier than those from the highest density and also the fat content increased with decreasing density. Females weighed less and contained less fat than males. Male offspring from lower densities produced larger amounts of the pheromone components cis-verbenol and 2-methyl-3-buten-2-ol than males from the higher densities. Offspring from the highest density produced about half as many progeny as those from the lowest densities, showing an effect of density acting over more than one generation. Density-induced variation of beetle 'quality' might be of importance in the population dynamics of bark beetles.-from Authors
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| 6. |
- Anderbrant, Olle, et al.
(författare)
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Pheromone of the elm bark beetle Scolytus laevis (Coleoptera Scolytidae) : stereoisomers of 4-methyl-3-heptanol reduce interspecific competition
- 2010
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Ingår i: Chemoecology. - : Springer Science and Business Media LLC. - 0937-7409 .- 1423-0445. ; 20:3, s. 179-187
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Tidskriftsartikel (refereegranskat)abstract
- Stereoisomers of 4-methyl-3-heptanol (MH) are pheromone components of several Scolytus bark beetles. The elm bark beetle Scolytus laevis (Coleoptera: Scolytidae) has in previous studies been caught in traps baited with commercial MH containing all four stereoisomers, but the lure has been considered a weak attractant. In this study, we addressed the question whether stereospecific responses by S. laevis to stereoisomers of MH might contribute to its niche separation from other sympatric Scolytus species. Using GC-MS, we analyzed extracts of hindguts and abdomens from male and female S. laevis and the sympatric S. triarmatus. We also tested all four MH-stereoisomers individually and in combinations in the field to determine their role for S. laevis. All four stereoisomers were synthesized via a boronic ester method with 1,2-dicyclohexylethanediol as chiral director. In addition, the (3S,4R)-stereoisomer of MH was prepared through enantioselective, lipase-mediated transesterification of a mixture of the four stereoisomers of MH. Females of both species contained small amounts of syn-MH, and males contained trace amounts of anti-MH. The anti stereoisomer (3R,4S)-MH was attractive to male and female S. laevis, whereas the syn stereoisomer (3S,4S)-MH acted as an inhibitor or deterrent and reduced the catch when added to the attractive isomer. The syn isomer is the main aggregation pheromone component of the larger and sympatric S. scolytus and possibly also of S. triarmatus. The avoidance response of S. laevis to the (3S,4S)-stereoisomer may reduce interspecific competition for host trees.
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| 8. |
- Andersson, Martin N, et al.
(författare)
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Characterization of olfactory sensory neurons in the white clover seed weevil, Apion fulvipes (Coleoptera: Apionidae).
- 2012
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Ingår i: Journal of Insect Physiology. - : Elsevier BV. - 1879-1611 .- 0022-1910. ; 58:10, s. 1325-1333
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Tidskriftsartikel (refereegranskat)abstract
- Seed-eating Apion weevils (Coleoptera: Apionidae) cause large economic losses in white and red clover seed production across Europe. Monitoring and control of clover weevils would be facilitated by semiochemical-based methods. Until now, however, nothing was known about physiological or behavioral responses to semiochemicals in this insect group. Here we analyzed the antenna of the white clover (Trifolium repens L.) specialist Apion fulvipes Geoffroy with scanning electron microscopy, and used single sensillum recordings with a set of 28 host compounds to characterize 18 classes of olfactory sensory neurons (OSNs). Nine of the OSN classes responded strongly to synthetic compounds with high abundance in clover leaves, flowers, or buds. Eight classes responded only weakly to the synthetic stimuli, whereas one collective class responded exclusively to volatiles released from a crushed clover leaf. The OSNs showed a remarkable degree of specificity, responding to only one or a few chemically related compounds. In addition, we recorded a marked difference in the temporal dynamics of responses between different neurons, compounds, and doses. The identified physiologically active compounds will be screened for behavioral activity, with the ultimate goal to develop an odor-based control strategy for this pest.
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| 9. |
- Bellas, Juan, et al.
(författare)
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Effects of medetomidine, a novel antifouling agent, on the burrowing bivalve Abra nitida (Muller)
- 2006
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 65:4, s. 575-582
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Tidskriftsartikel (refereegranskat)abstract
- The effects of medetomidine, a novel antifouling candidate, on the burrowing bivalve Abra nitida were studied. The burrowing behaviour, sediment reworking activity and faeces production were assessed after 24 h exposure of A. nitida to sublethal concentrations of medetomidine. Medetomidine caused a significant decrease in the burrowing response and in the sediment reworking activity. The median effective concentrations (EC50) were 430 nM (86 mu g/l) and 4.4 nM (0.9 mu g/l), respectively. No effects on the faeces production were detected. Although significant effects of medetomidine on A. nitida were registered, a reversibility of the effects was observed when 24 hexposed animals were incubated in clean seawater and sediment for 24 h. Considerations relating to the future commercialisation of medetomidine for antifouling purposes are discussed. (c) 2006 Elsevier Ltd. All rights reserved.
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| 10. |
- Binyameen, Muhammad, et al.
(författare)
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Identification of Plant Semiochemicals and Characterization of New Olfactory Sensory Neuron Types in a Polyphagous Pest Moth, Spodoptera littoralis
- 2014
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Ingår i: Chemical Senses. - : Oxford University Press (OUP). - 0379-864X .- 1464-3553. ; 39, s. 719-733
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Tidskriftsartikel (refereegranskat)abstract
- Phytophagous insects use blends of volatiles released from plants to select hosts for feeding and oviposition. To behaviorally analyze complex blends, we need efficient and selective methods for elucidating neuron types, their ligands, and specificity. Gas chromatography-combined single sensillum recordings (GC-SSRs) from antennal olfactory sensilla of female moth, Spodoptera littoralis revealed 38 physiologically active peaks in the headspace volatile blends from both larvae-damaged cotton plants and lilac flowers. Using GC-combined mass spectrometry, 9 new physiologically active compounds were identified from damaged cotton and 11 from lilac compared with earlier electrophysiological studies using antennae of female S. littoralis. We characterized 14 novel classes of olfactory sensory neurons (OSNs). Among these, we found the first 2 ligands for a frequent type of short trichoid sensillum, for which no ligands were identified earlier. By using GC-SSR, a substantial increase in functional classes of OSNs and active compounds, 40% and 34% more, respectively, compared with recent studies using GC-electroantennogram or SSR using single compounds was detected. Compared with the estimated number of corresponding antennal olfactory receptors, the OSN classes now correspond to 83% of a likely maximum. The many specialist OSNs observed may facilitate behavioral confirmation of key plant volatiles in blends.
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