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Mobile passive samplers: Concept for a novel mode of exposure Texto completo
2011
Allan, Ian J. | Nilsson, Hans C. | Tjensvoll, Ingrid | Bradshaw, Clare | Næs, Kristoffer
Integrative passive sampling with devices such as semipermeable membrane devices generally relies on rigs for month-long static exposures in water. We evaluate here whether mobile exposures of passive samplers can provide reliable estimates of dissolved contaminant concentrations. Mobile exposures were obtained by towing samplers fastened to the end of a benthic trawl net. Significant and reproducible absorption of polycyclic aromatic hydrocarbons during 5 h-long deployments was made possible by high sampling rates resulting from high water turbulences during towing at 1.2–1.5 knots. Sampling rates (72–215 L d⁻¹) estimated from the dissipation of performance reference compounds were supported by in situ calibration with samplers exposed for a 30 days in the vicinity of the test site. Higher fluoranthene and pyrene absorption in samplers exposed to the trawling-induced sediment plume could be attributed to desorption from re-suspended sediments. This mode of exposure has the potential to be used in monitoring programmes.
Mostrar más [+] Menos [-]The effect of mercury on trees and their mycorrhizal fungi Texto completo
2011
Jean-Philippe, Sharon R. | Franklin, Jennifer A. | Buckley, David S. | Hughes, Karen
The Oak Ridge Reservation, established in 1942, was the designated site for the construction of the atomic bomb. During a 20-year period from 1944 to 1963 radioactive and toxic chemical pollutants, especially mercury compounds were released into the surrounding waterways. Tree diversity and mycorrhizal presence and abundance were analyzed in the mercury-contaminated floodplains of East Fork Poplar Creek Oak Ridge (EFPC) (Tennessee). A subsequent greenhouse study was conducted to assess the phytotoxic effects of different mercuric solutions on Platanus occidentalis (American Sycamore), inoculated with soils from EFPC. Total soil mercury in the field had no effect on tree diversity. Organic species of mercury proved to be more toxic than inorganic species of mercury and soil inoculants from EFPC had no protective effects against Hg toxicity in our greenhouse study. Comparison of the effects of mercury contamination in our field and greenhouse studies was difficult due to uncontrolled factors.
Mostrar más [+] Menos [-]Atmospheric phenanthrene pollution modulates carbon allocation in red clover (Trifolium pratense L.) Texto completo
2011
Desalme, Dorine | Binet, Philippe | Epron, Daniel | Bernard, Nadine | Gilbert, Daniel | Toussaint, Marie-Laure | Plain, Caroline | Chiapusio, Geneviève
Atmospheric phenanthrene pollution modulates carbon allocation in red clover (Trifolium pratense L.) Texto completo
2011
Desalme, Dorine | Binet, Philippe | Epron, Daniel | Bernard, Nadine | Gilbert, Daniel | Toussaint, Marie-Laure | Plain, Caroline | Chiapusio, Geneviève
The influence of atmospheric phenanthrene (PHE) exposure (160μgm⁻³) during one month on carbon allocation in clover was investigated by integrative (plant growth analysis) and instantaneous ¹³CO₂ pulse-labelling approaches. PHE exposure diminished plant growth parameters (relative growth rate and net assimilation rate) and disturbed photosynthesis (carbon assimilation rate and chlorophyll content), leading to a 25% decrease in clover biomass. The root-shoot ratio was significantly enhanced (from 0.32 to 0.44). Photosynthates were identically allocated to leaves while less allocated to stems and roots. PHE exposure had a significant overall effect on the ¹³C partitioning among clover organs as more carbon was retained in leaves at the expense of roots and stems. The findings indicate that PHE decreases root exudation or transfer to symbionts and in leaves, retains carbon in a non-structural form diverting photosynthates away from growth and respiration (emergence of an additional C loss process).
Mostrar más [+] Menos [-]Atmospheric phenanthrene pollution modulates carbon allocation in red clover (Trifolium pratense L.) Texto completo
2011
Desalme, Dorine | Binet, Philippe | Epron, Daniel, D. | Bernard, Nadine | Gilbert, Daniel | Toussaint, Marie-Laure | Plain, Caroline | Chiapusio, Geneviève | Laboratoire Chrono-environnement (UMR 6249) (LCE) ; Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) ; Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC) | Ecologie et Ecophysiologie Forestières [devient SILVA en 2018] (EEF) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Pays de Montbeliard Agglomeration (PMA)
International audience | The influence of atmospheric phenanthrene (PHE) exposure (160 mgm 3) during one month on carbon allocation in clover was investigated by integrative (plant growth analysis) and instantaneous 13CO2 pulse-labelling approaches. PHE exposure diminished plant growth parameters (relative growth rate and net assimilation rate) and disturbed photosynthesis (carbon assimilation rate and chlorophyll content), leading to a 25% decrease in clover biomass. The root-shoot ratio was significantly enhanced (from 0.32 to 0.44). Photosynthates were identically allocated to leaves while less allocated to stems and roots. PHE exposure had a significant overall effect on the 13C partitioning among clover organs as more carbon was retained in leaves at the expense of roots and stems. The findings indicate that PHE decreases root exudation or transfer to symbionts and in leaves, retains carbon in a non-structural form diverting photosynthates away from growth and respiration (emergence of an additional C loss process).
Mostrar más [+] Menos [-]Heavy metal pollution exerts reduction/adaptation in the diversity and enzyme expression profile of heterotrophic bacteria in Cochin estuary, India Texto completo
2011
Jose, Jiya | Giridhar, Rajesh | Anas, Abdulaziz | Loka Bharathi, P.A. | Nair, Shanta
Heavy metal pollution exerts reduction/adaptation in the diversity and enzyme expression profile of heterotrophic bacteria in Cochin estuary, India Texto completo
2011
Jose, Jiya | Giridhar, Rajesh | Anas, Abdulaziz | Loka Bharathi, P.A. | Nair, Shanta
Over the past three decades heavy metal pollution has increased substantially in Cochin estuary, south west coast of India. Here we studied the distribution, diversity and enzyme expression profile of culturable microbial population along a pollution gradient. The distribution of resistance against 5 mM concentration of Zn, Co, Ni and Cu was observed among 90–100% of bacterial isolates retrieved from highly polluted Eloor, whereas it was less than 40% in Vypin and Munambam. Similarly, there was a difference in the distribution and diversity of bacterial phyla with predominance of Proteobacteria in Eloor and Firmicutes in Munambam and Vypin. We observed that 75–100% of the organisms retrieved from Eloor had low levels of expression for hydrolytic enzyme. In conclusion, the heavy metal pollution in Cochin estuary brought in reduction/adaptation in the distribution, diversity and enzyme expression profile of bacteria, which may impart adverse impacts on ecosystem functioning.
Mostrar más [+] Menos [-]Heavy metal pollution exerts reduction/adaptation in the diversity and enzyme expression profile of heterotrophic bacteria in Cochin estuary, India
2011
Jose, J. | Giridhar, R. | Anas, A. | LokaBharathi, P.A. | Nair, S.
Over the past three decades heavy metal pollution has increased substantially in Cochin estuary, south west coast of India. The distribution, diversity and enzyme expression profile of culturable microbial population along a pollution gradient was studied. The distribution of resistance against 5 mM concentration of Zn, Co, Ni and Cu was observed among 90-100% of bacterial isolates retrieved from highly polluted Eloor, whereas it was less than 40% in Vypin and Munambam. Similarly, there was a difference in the distribution and diversity of bacterial phyla with predominance of Proteobacteria in Eloor and Firmicutes in Munambam and Vypin. We observed that 75-100% of the organisms retrieved from Eloor had low levels of expression for hydrolytic enzyme. In conclusion, the heavy metal pollution in Cochin estuary brought in reduction/adaptation in the distribution, diversity and enzyme expression profile of bacteria, which may impart adverse impacts on ecosystem functioning.
Mostrar más [+] Menos [-]Uranium bioaccumulation and biological disorders induced in zebrafish (Danio rerio) after a depleted uranium waterborne exposure Texto completo
2011
Barillet, Sabrina | Adam-Guillermin, Christelle | Palluel, Olivier | Porcher, Jean-Marc | Devaux, Alain
Because of its toxicity and its ubiquity within aquatic compartments, uranium (U) represents a significant hazard to aquatic species such as fish. In a previous study, we investigated some biological responses in zebrafish either exposed to depleted or to enriched U (i.e., to different radiological activities). However, results required further experiments to better understand biological responses. Moreover, we failed to clearly demonstrate a significant relationship between biological effects and U radiological activity. We therefore chose to herein examine U bioaccumulation and induced effects in zebrafish according to a chemical dose–response approach. Results showed that U is highly bioconcentrated in fish, according to a time- and concentration-dependent model. Additionally, hepatic antioxidant defenses, red blood cells DNA integrity and brain acetylcholinesterase activity were found to be significantly altered. Generally, the higher the U concentration, the sooner and/or the greater the effect, suggesting a close relationship between accumulation and effect.
Mostrar más [+] Menos [-]Assessing the recovery potential of alpine moss–sedge heath: Reciprocal transplants along a nitrogen deposition gradient Texto completo
2011
Armitage, Heather F. | Britton, Andrea J. | Woodin, Sarah J. | Wal, René van der
The potential of alpine moss–sedge heath to recover from elevated nitrogen (N) deposition was assessed by transplanting Racomitrium lanuginosum shoots and vegetation turfs between 10 elevated N deposition sites (8.2–32.9 kg ha⁻¹ yr⁻¹) and a low N deposition site, Ben Wyvis (7.2 kg ha⁻¹ yr⁻¹). After two years, tissue N of Racomitrium shoots transplanted from higher N sites to Ben Wyvis only partially equilibrated to reduced N deposition whereas reciprocal transplants almost matched the tissue N of indigenous moss. Unexpectedly, moss shoot growth was stimulated at higher N deposition sites. However, moss depth and biomass increased in turfs transplanted to Ben Wyvis, apparently due to slower shoot turnover (suggested to result partly from decreased tissue C:N slowing decomposition), whilst abundance of vascular species declined. Racomitrium heath has the potential to recover from the impacts of N deposition; however, this is constrained by the persistence of enhanced moss tissue N contents.
Mostrar más [+] Menos [-]A rapid and high-throughput quantum dots bioassay for monitoring of perfluorooctane sulfonate in environmental water samples Texto completo
2011
Zhang, Jiong | Wan, Yanjian | Li, Yuanyuan | Zhang, Qiongfang | Xu, Shunqing | Zhu, Huijun | Shu, Baihua
Currently HPLC/MS is the state of the art tool for environmental/drinking water perfluorooctane sulfonate (PFOS) monitoring. PFOS can bind to peroxisomal proliferator-activated receptor-alpha (PPARα), which forms heterodimers with retinoid X receptors (RXRs) and binds to PPAR response elements. In this bioassay free PFOS in water samples competes with immobilized PFOS in ELISA plates for a given amount of PPARα–RXRα. It can be determined indirectly by immobilizing PPARα–RXRα–PFOS complex to another plate coated with PPARα antibody and subsequent measuring the level of PPARα–RXRα by using biotin-modified PPARα–RXRα probes–quantum dots–streptavidin detection system. The rapid and high-throughput bioassay demonstrated a detection limit of 2.5 ng L⁻¹ with linear range between 2.5 ng L⁻¹ and 75 ng L⁻¹. Detection results of environmental water samples were highly consistent between the bioassay and HPLC/MS.
Mostrar más [+] Menos [-]Urban nonpoint source pollution buildup and washoff models for simulating storm runoff quality in the Los Angeles County Texto completo
2011
Wang, Long | Wei, Jiahua | Huang, Yuefei | Wang, Guangqian | Maqsood, Imran
Many urban nonpoint source pollution models utilize pollutant buildup and washoff functions to simulate storm runoff quality of urban catchments. In this paper, two urban pollutant washoff load models are derived using pollutant buildup and washoff functions. The first model assumes that there is no residual pollutant after a storm event while the second one assumes that there is always residual pollutant after each storm event. The developed models are calibrated and verified with observed data from an urban catchment in the Los Angeles County. The application results show that the developed model with consideration of residual pollutant is more capable of simulating nonpoint source pollution from urban storm runoff than that without consideration of residual pollutant. For the study area, residual pollutant should be considered in pollutant buildup and washoff functions for simulating urban nonpoint source pollution when the total runoff volume is less than 30mm.
Mostrar más [+] Menos [-]Partitioning behaviour of perfluorinated alkyl contaminants between water, sediment and fish in the Orge River (nearby Paris, France) Texto completo
2011
Labadie, Pierre | Chevreuil, Marc
This paper reports on the partitioning behaviour of 15 perfluorinated compounds (PFCs), including C₄–C₁₀ sulfonates and C₅–C₁₄ carboxylic acids, between water, sediment and fish (European chub, Leuciscus cephalus) in the Orge River (nearby Paris). Total PFC levels were 73.0±3.0ngL⁻¹ in water and 8.4±0.5ngg⁻¹ in sediment. They were in the range 43.1–4997.2ngg⁻¹ in fish, in which PFC tissue distribution followed the order plasma>liver>gills>gonads>muscle. Sediment–water distribution coefficients (logKd) and bioaccumulation factors (logBAF) were in the range 0.8–4.3 and 0.9–6.7, respectively. Both distribution coefficients positively correlated with perfluoroalkyl chain length. Field-based biota–sediment accumulation factors (BSAFs) are also reported, for the first time for PFCs other than perfluorooctane sulfonate. logBSAF ranged between −1.3 and 1.5 and was negatively correlated with the perfluoroalkyl chain length in the case of carboxylic acids.
Mostrar más [+] Menos [-]Characteristics of the event mean concentration (EMC) from rainfall runoff on an urban highway Texto completo
2011
Lee, Ju Young | Kim, Hyoungjun | Kim, Youngjin | Han, M. Y.
The purpose of this study was to investigate the characterization of the event mean concentration (EMC) of runoff during heavy precipitation events on highways. Highway runoff quality data were collected from the 7th highway, in South Korea during 2007–2009. The samples were analyzed for runoff quantity and quality parameters such as CODcᵣ, TSS, TPHs, TKN, NO₃, TP, PO₄ and six heavy metals, e.g., As, Cu, Cd, Ni, Pb and Zn. Analysis of resulting hydrographs and pollutant graphs indicates that the peak of the pollutant concentrations in runoff occurs 20 min after the first rainfall runoff occurrence. The first flush effect depends on the preceding dry period and the rainfall intensity. The results of this study can be used as a reference for water quality management of urban highways.
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