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Ute Feiler - One of the best experts on this subject based on the ideXlab platform.
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Sediment contact test with Myriophyllum aquaticum (ISO/DIS 16191) : results of an international ring test
2012Co-Authors: Ute Feiler, Gertie Arts, Christine Bazin, D. Belgers, U. Biermann, Frank Brauer, Carmen Casado, L. Doren, Britta Eklund, Daniel GilbergAbstract:Although they are an important part of an aquatic ecosystem, dicotyledonous macrophytes are not yet part of the risk assessment of sediments or dredged material. A sediment contact test system with the dicotyledonous watermilfoil Myriophyllum aquaticum was established by the ecotoxicological laboratory of the German Federal Institute of Hydrology. This test procedure is now in the standardisation process within ISO. In the sediment contact test, Myriophyllum aquaticum whorls are exposed to environmental samples for ten days. The growth of Myriophyllum aquaticum in a test sample is compared with its growth in the control sample. Phytotoxic effects can be quantified as growth inhibition (%) relative to the control growth. Several laboratories from academia, industries and government participated in an interlaboratory ring test organized by the German Federal Institute of Hydrology. The ring test aimed at i) investigating the practicability and reproducibility of the sediment contact test, ii) validating the chosen endpoint, and iii) determining the response range of the reference substance functioning as positive control.
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Comparing growth development of Myriophyllum spp. in laboratory and field experiments for ecotoxicological testing
Environmental science and pollution research international, 2008Co-Authors: Katja Knauer, Silvia Mohr, Ute FeilerAbstract:Background, goals and scope Risk assessment of herbicides and the evaluation of contaminated sediments based on algae and the macrophyte Lemna sp. alone may underestimate the potential hazard of certain compounds. Therefore, various test systems with Myriophyllum spp. have been developed recently to assess the phytotoxicity in surface waters and natural sediments. In the present study, experiments investigating the growth development of Myriophyllum spp. were performed in the laboratory under defined conditions and in mesocosms under environmentally realistic exposure conditions to evaluate the suitability of these species as potential standard test organisms in ecotoxicological testing. This study provides data on the endpoints biomass, plant length and root development.
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Application of a new sediment contact test with Myriophyllum aquaticum and of the aquatic Lemna test to assess the sediment quality of Lake Skadar
Journal of Soils and Sediments, 2007Co-Authors: Danijela Stešević, Ute Feiler, Danijela Sundic, S. Mijovic, Lothar Erdinger, Thomas-benjamin Seiler, Peter Heininger, Henner HollertAbstract:Situated in the transboundary belt between Montenegro and Albania, Lake Skadar is the largest freshwater reservoir in Southeastern Europe. Because of the wide range of endemic, rare or endangered plant and animal species it supports, Lake Skadar and its extensive adjacent wetlands are internationally recognised as a site of significance and importance (Ramsar site). Within the last 10 to 20 years, Lake Skadar was exposed to intensive pollution. For the assessment of the ecotoxic load of the sediments sampled in Lake Skadar, a triad approach was recently applied. Overall, a complex spectrum of ecotoxic loads was elucidated. The aim of the present study was to use plant-based bioassays for assessing the sediment quality of Lake Skadar in order to facilitate and complement the triad test battery. The newly developed sediment contact test with Myriophyllum aquaticum and the aquatic growth inhibition test with Lemna minor were applied to native sediments and pore water, respectively, allowing the investigation of different toxicity-effects caused by particle-bound pollutants as well as pollutants in the interstitial water. This investigation is the first application of the novel sediment contact test with Myriophyllum aquaticum to lake sediments. Sediment samples were taken from nine selected sites at Lake Skadar and investigated by the sediment contact assay with Myriophyllum aquaticum. The pore water was extracted from these sediment samples to be analysed in the aquatic growth inhibition test with Lemna minor. The results of the sediment contact tests were compared with each other and with those of the aquatic growth inhibition test. Both applied macrophyte biotests revealed distinct changes in the growth behaviour of the two macrophytes subsequent to the exposure to the investigated natural sediments of Lake Skadar. The Myriophyllum sediment contact test revealed significant toxicity in the sediment samples from Radus and Kamenik, whereas the aquatic Lemna test showed inhibition effects for the samples from Sterbeq, Plavnica and Kamice. Data obtained with the newly developed Danio rerio contact test and the Arthrobacter globiformis contact test confirmed the Myriophyllum results. Analyses of the heavy metal content in the sediments revealed low or moderate contamination levels. Correlation analyses between the content of heavy metals in the sediments and growth inhibition of Myriophyllum aquaticum showed a significant correlation between Cr concentrations and growth inhibition. Comparable findings are available for a German river system. In contrast, no significant correlation between inhibition rates and concentration of metals could be observed with Lemna minor. It was shown that the newly developed sediment contact test with Myriophyllum aquaticum is applicable to lake sediments. In both the sediment contact test with Myriophyllum aquaticum on whole sediments and the aquatic growth inhibition test with Lemna minor on pore water, plant growth was influenced by the natural sediments and its components. Therefore, both test systems were found to be suitable for the detection of phytotoxic effects upon exposure to sediments. Myriophyllum aquaticum as test organism of the contact test grows directly in the sediment without an additional water-layer. Thus, it is able to detect toxicity caused by particle-bound phytotoxic substances as well as pore water-related contamination, while the floating Lemna minor can only detect effects emanating from pore water. Significant differences of the results were observed between these two test systems and, accordingly, the two different exposure scenarios. Hence, none of the tests can replace the other one and, as a consequence, both should be included into a test battery for the assessment of sediment toxicity. Both plant assays were shown to be reliable tools for the evaluation of the eco-toxicological risk potentials of pore water and solid-phase sediment. They should become a complement to the standardised test battery generally used for comprehensive hazard assessment.
Keith R. Solomon - One of the best experts on this subject based on the ideXlab platform.
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Microcosm Evaluation of the Fate, Toxicity, and Risk to Aquatic Macrophytes from Perfluorooctanoic Acid (PFOA)
Archives of Environmental Contamination and Toxicology, 2005Co-Authors: Mark L. Hanson, Jeff Small, Paul K. Sibley, Tim M. Boudreau, Richard A. Brain, Scott A. Mabury, Keith R. SolomonAbstract:Perfluorooctanoic acid (PFOA) is an anthropogenic contaminant detected in various environmental and biological matrices. This compound is a fluorinated surfactant, belonging to a class of molecules known for persistence and their global distribution, but for which little ecotoxicological data are currently available, especially under field conditions. The environmental fate and toxicity of PFOA to the aquatic macrophytes Myriophyllum sibiricum and M. spicatum were investigated using 12,000 L outdoor microcosms. Replicate microcosms ( n = 3) were treated with 0.3, 1, 30, and 100 mg/L PFOA as the sodium salt, plus controls, and assessed at regular intervals over 35 days. PFOA showed no significant dissipation from the water column, except at the greatest concentration, where partitioning from the water column into other compartments is suspected. The two species of Myriophyllum were similar in their sensitivity to PFOA under these simulated field conditions. Toxicity after 14 to 35 days of exposure in the evaluated endpoints for M. spicatum was ≥5.7 mg/L PFOA for EC_10s and ≥31.8 mg/L PFOA for EC_50s and in M. sibiricum was ≥8.4 mg/L PFOA for EC_10s and ≥35.8 mg/L PFOA for EC_50s. The no observed effects concentrations (NOECs) for Myriophyllum spp . were consistently ≥23.9 mg/L PFOA. A risk assessment for these plant species estimated a negligible probability of toxicity being observed from PFOA exposure at current environmental concentrations.
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Variation, replication, and power analysis of Myriophyllum spp. microcosm toxicity data.
Environmental toxicology and chemistry, 2003Co-Authors: Mark L. Hanson, Hans Sanderson, Keith R. SolomonAbstract:Myriophyllum spp. have been proposed as a new standard laboratory aquatic macrophyte test species for the registration of pesticides. The main objectives of this investigation were to determine the power of Myriophyllum sibiricum and Myriophyllum spicatum toxicity data derived from an outdoor microcosm bioassay, to evaluate the variation of 10 different aquatic plant endpoints and to calculate the minimum detectable difference for these endpoints, to determine the replication required to detect ecologically significant changes from control for these endpoints, and to make recommendations for future field studies with Myriophyllum spp. Control data from four different studies that characterized haloacetic acid toxicity with Myriophyllum spp. for durations of three to six weeks during the summer of 1999 with five treatment levels (n = 3), including control, were examined. Endpoint coefficient of variation ranged, on average, from 6 to 28%. Node number and plant length endpoints were consistently the most statistically powerful for both plant species. It was possible to detect −30% change from control in both endpoints with high statistical power (β = 0.2, α = 0.05, n = 3). The range of minimum detectable differences was 40 to 60% for the other endpoints. Replication to detect a ≥25% change from control would require an n of 2 to 21, depending on the endpoint. Myriophyllum sibiricum had slightly lower coefficients of variation and thus required fewer replicates than M. spicatum to be statistically significantly different from control values. Variation within microcosm studies was not significantly different from that of controlled laboratory studies, implying that most of the variation observed in the field is inherent in the plants. Based on statistical sensitivity, ecological relevance, and toxicological sensitivity, we recommend using plant length and root endpoints as indicators of toxicity under field conditions.
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evaluation of monochloroacetic acid mca degradation and toxicity to lemna gibba Myriophyllum spicatum and Myriophyllum sibiricum in aquatic microcosms
Aquatic Toxicology, 2002Co-Authors: Mark L. Hanson, Paul K. Sibley, Scott A. Mabury, David A Ellis, Derek C G Muir, Keith R. SolomonAbstract:Abstract The fate of monochloroacetic acid (MCA), a common phytotoxic aquatic contaminant, and its toxicity to the aquatic macrophytes Lemna gibba ( L. gibba ), Myriophyllum spicatum ( M. spicatum ), and Myriophyllum sibiricum ( M. sibiricum ) under semi-natural field conditions was studied. Replicate 12,000 l enclosures were treated with 0, 3, 10, 30 and 100 mg/l of MCA. Each microcosm was stocked with eight individual apical shoots of M. spicatum and M. sibiricum 1 day prior to initiation of exposure. Plants were sampled after 4, 7, 14 and 28 days of exposure and their response assessed using numerous somatic and biochemical endpoints. L. gibba was introduced into the microcosms the day of MCA treatment and monitored regularly for 21 days. The half-life of MCA in the water column ranged between 86 and 523 h. The most sensitive plant species was M. spicatum , followed by M. sibiricum and L. gibba . All species demonstrated toxicity within a threefold range of each other. Endpoint sensitivity varied depending on the duration of exposure and the level of effect chosen. Most species endpoint EC x values were less than an order of magnitude different. Citrate levels in Myriophyllum spp. were not influenced by exposure to MCA. The toxicity of MCA to M. spicatum and M. sibiricum was very similar and thus highly predictive of toxicity observed for each other. The EC 10 was a more conservative estimate of toxicity than the statistically derived no observed effect concentration. Current concentrations of MCA are not likely to pose a risk to these aquatic plants in surface waters.
Mark L. Hanson - One of the best experts on this subject based on the ideXlab platform.
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Microcosm Evaluation of the Fate, Toxicity, and Risk to Aquatic Macrophytes from Perfluorooctanoic Acid (PFOA)
Archives of Environmental Contamination and Toxicology, 2005Co-Authors: Mark L. Hanson, Jeff Small, Paul K. Sibley, Tim M. Boudreau, Richard A. Brain, Scott A. Mabury, Keith R. SolomonAbstract:Perfluorooctanoic acid (PFOA) is an anthropogenic contaminant detected in various environmental and biological matrices. This compound is a fluorinated surfactant, belonging to a class of molecules known for persistence and their global distribution, but for which little ecotoxicological data are currently available, especially under field conditions. The environmental fate and toxicity of PFOA to the aquatic macrophytes Myriophyllum sibiricum and M. spicatum were investigated using 12,000 L outdoor microcosms. Replicate microcosms ( n = 3) were treated with 0.3, 1, 30, and 100 mg/L PFOA as the sodium salt, plus controls, and assessed at regular intervals over 35 days. PFOA showed no significant dissipation from the water column, except at the greatest concentration, where partitioning from the water column into other compartments is suspected. The two species of Myriophyllum were similar in their sensitivity to PFOA under these simulated field conditions. Toxicity after 14 to 35 days of exposure in the evaluated endpoints for M. spicatum was ≥5.7 mg/L PFOA for EC_10s and ≥31.8 mg/L PFOA for EC_50s and in M. sibiricum was ≥8.4 mg/L PFOA for EC_10s and ≥35.8 mg/L PFOA for EC_50s. The no observed effects concentrations (NOECs) for Myriophyllum spp . were consistently ≥23.9 mg/L PFOA. A risk assessment for these plant species estimated a negligible probability of toxicity being observed from PFOA exposure at current environmental concentrations.
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Variation, replication, and power analysis of Myriophyllum spp. microcosm toxicity data.
Environmental toxicology and chemistry, 2003Co-Authors: Mark L. Hanson, Hans Sanderson, Keith R. SolomonAbstract:Myriophyllum spp. have been proposed as a new standard laboratory aquatic macrophyte test species for the registration of pesticides. The main objectives of this investigation were to determine the power of Myriophyllum sibiricum and Myriophyllum spicatum toxicity data derived from an outdoor microcosm bioassay, to evaluate the variation of 10 different aquatic plant endpoints and to calculate the minimum detectable difference for these endpoints, to determine the replication required to detect ecologically significant changes from control for these endpoints, and to make recommendations for future field studies with Myriophyllum spp. Control data from four different studies that characterized haloacetic acid toxicity with Myriophyllum spp. for durations of three to six weeks during the summer of 1999 with five treatment levels (n = 3), including control, were examined. Endpoint coefficient of variation ranged, on average, from 6 to 28%. Node number and plant length endpoints were consistently the most statistically powerful for both plant species. It was possible to detect −30% change from control in both endpoints with high statistical power (β = 0.2, α = 0.05, n = 3). The range of minimum detectable differences was 40 to 60% for the other endpoints. Replication to detect a ≥25% change from control would require an n of 2 to 21, depending on the endpoint. Myriophyllum sibiricum had slightly lower coefficients of variation and thus required fewer replicates than M. spicatum to be statistically significantly different from control values. Variation within microcosm studies was not significantly different from that of controlled laboratory studies, implying that most of the variation observed in the field is inherent in the plants. Based on statistical sensitivity, ecological relevance, and toxicological sensitivity, we recommend using plant length and root endpoints as indicators of toxicity under field conditions.
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evaluation of monochloroacetic acid mca degradation and toxicity to lemna gibba Myriophyllum spicatum and Myriophyllum sibiricum in aquatic microcosms
Aquatic Toxicology, 2002Co-Authors: Mark L. Hanson, Paul K. Sibley, Scott A. Mabury, David A Ellis, Derek C G Muir, Keith R. SolomonAbstract:Abstract The fate of monochloroacetic acid (MCA), a common phytotoxic aquatic contaminant, and its toxicity to the aquatic macrophytes Lemna gibba ( L. gibba ), Myriophyllum spicatum ( M. spicatum ), and Myriophyllum sibiricum ( M. sibiricum ) under semi-natural field conditions was studied. Replicate 12,000 l enclosures were treated with 0, 3, 10, 30 and 100 mg/l of MCA. Each microcosm was stocked with eight individual apical shoots of M. spicatum and M. sibiricum 1 day prior to initiation of exposure. Plants were sampled after 4, 7, 14 and 28 days of exposure and their response assessed using numerous somatic and biochemical endpoints. L. gibba was introduced into the microcosms the day of MCA treatment and monitored regularly for 21 days. The half-life of MCA in the water column ranged between 86 and 523 h. The most sensitive plant species was M. spicatum , followed by M. sibiricum and L. gibba . All species demonstrated toxicity within a threefold range of each other. Endpoint sensitivity varied depending on the duration of exposure and the level of effect chosen. Most species endpoint EC x values were less than an order of magnitude different. Citrate levels in Myriophyllum spp. were not influenced by exposure to MCA. The toxicity of MCA to M. spicatum and M. sibiricum was very similar and thus highly predictive of toxicity observed for each other. The EC 10 was a more conservative estimate of toxicity than the statistically derived no observed effect concentration. Current concentrations of MCA are not likely to pose a risk to these aquatic plants in surface waters.
Henner Hollert - One of the best experts on this subject based on the ideXlab platform.
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Application of a new sediment contact test with Myriophyllum aquaticum and of the aquatic Lemna test to assess the sediment quality of Lake Skadar
Journal of Soils and Sediments, 2007Co-Authors: Danijela Stešević, Ute Feiler, Danijela Sundic, S. Mijovic, Lothar Erdinger, Thomas-benjamin Seiler, Peter Heininger, Henner HollertAbstract:Situated in the transboundary belt between Montenegro and Albania, Lake Skadar is the largest freshwater reservoir in Southeastern Europe. Because of the wide range of endemic, rare or endangered plant and animal species it supports, Lake Skadar and its extensive adjacent wetlands are internationally recognised as a site of significance and importance (Ramsar site). Within the last 10 to 20 years, Lake Skadar was exposed to intensive pollution. For the assessment of the ecotoxic load of the sediments sampled in Lake Skadar, a triad approach was recently applied. Overall, a complex spectrum of ecotoxic loads was elucidated. The aim of the present study was to use plant-based bioassays for assessing the sediment quality of Lake Skadar in order to facilitate and complement the triad test battery. The newly developed sediment contact test with Myriophyllum aquaticum and the aquatic growth inhibition test with Lemna minor were applied to native sediments and pore water, respectively, allowing the investigation of different toxicity-effects caused by particle-bound pollutants as well as pollutants in the interstitial water. This investigation is the first application of the novel sediment contact test with Myriophyllum aquaticum to lake sediments. Sediment samples were taken from nine selected sites at Lake Skadar and investigated by the sediment contact assay with Myriophyllum aquaticum. The pore water was extracted from these sediment samples to be analysed in the aquatic growth inhibition test with Lemna minor. The results of the sediment contact tests were compared with each other and with those of the aquatic growth inhibition test. Both applied macrophyte biotests revealed distinct changes in the growth behaviour of the two macrophytes subsequent to the exposure to the investigated natural sediments of Lake Skadar. The Myriophyllum sediment contact test revealed significant toxicity in the sediment samples from Radus and Kamenik, whereas the aquatic Lemna test showed inhibition effects for the samples from Sterbeq, Plavnica and Kamice. Data obtained with the newly developed Danio rerio contact test and the Arthrobacter globiformis contact test confirmed the Myriophyllum results. Analyses of the heavy metal content in the sediments revealed low or moderate contamination levels. Correlation analyses between the content of heavy metals in the sediments and growth inhibition of Myriophyllum aquaticum showed a significant correlation between Cr concentrations and growth inhibition. Comparable findings are available for a German river system. In contrast, no significant correlation between inhibition rates and concentration of metals could be observed with Lemna minor. It was shown that the newly developed sediment contact test with Myriophyllum aquaticum is applicable to lake sediments. In both the sediment contact test with Myriophyllum aquaticum on whole sediments and the aquatic growth inhibition test with Lemna minor on pore water, plant growth was influenced by the natural sediments and its components. Therefore, both test systems were found to be suitable for the detection of phytotoxic effects upon exposure to sediments. Myriophyllum aquaticum as test organism of the contact test grows directly in the sediment without an additional water-layer. Thus, it is able to detect toxicity caused by particle-bound phytotoxic substances as well as pore water-related contamination, while the floating Lemna minor can only detect effects emanating from pore water. Significant differences of the results were observed between these two test systems and, accordingly, the two different exposure scenarios. Hence, none of the tests can replace the other one and, as a consequence, both should be included into a test battery for the assessment of sediment toxicity. Both plant assays were shown to be reliable tools for the evaluation of the eco-toxicological risk potentials of pore water and solid-phase sediment. They should become a complement to the standardised test battery generally used for comprehensive hazard assessment.
Münevver Sökmen - One of the best experts on this subject based on the ideXlab platform.
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Changes in antioxidant activity, total phenolic and abscisic acid constituents in the aquatic plants Myriophyllum spicatum L. and Myriophyllum triphyllum Orchard exposed to cadmium
Ecotoxicology, 2007Co-Authors: Aysel Sivaci, E. Rıdvan Sivaci, Münevver SökmenAbstract:Changes in antioxidant activity, total phenolic and abscisic acid (ABA) constituents of Myriophyllum spicatum L. and Myriophyllum triphyllum Orchard, cadmium (Cd) aqueous macrophytes, were investigated exposed to 0, 2, 4, 6, 8, 16 mg l^-1 Cd concentrations. M. triphyllum exhibited strong antioxidant activity but not M. spicatum before and after exposure. Free radical scavenging activity of M. triphyllum was significantly affected from the Cd concentrations and a significant increase was observed at 6 mgl^-1 Cd concentration. Total phenolic constituent and ABA concentration of M. triphyllum is higher than that of M. spicatum with or without heavy metal exposure ( P
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Biosorption of cadmium by Myriophyllum spicatum L. and Myriophyllum triphyllum orchard
Chemosphere, 2004Co-Authors: E. Rıdvan Sivaci, Aysel Sivaci, Münevver SökmenAbstract:Abstract The aim of this study was to characterize the biological treatment of heavy metal-contaminated water employing Myriophyllum species, namely M. spicatum L. and M. triphyllum . Both species were found to be capable of removing cadmium (Cd) from water; the latter significantly outperformed. Myriophyllum species were treated with 0, 2, 4, 6, 8, 16 mg l −1 cadmium solutions for 24, 48, 72, 96 h, respectively. Cd uptake of both species was the lowest at 2 mg l −1 and the highest at 16 mg l −1 . Concentration related cadmium stress on both species exhibit significant difference on pigment levels (8–16 mg l −1 ). These findings contribute to the fact that submerged aquatic plants can be used for the removal of heavy metals.
