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Evidence of lead biomagnification in invertebrate predators from laboratory and field experiments 全文
2011
Rubio Franchini, Isidoro | Rico Martínez, Roberto
This report includes atomic absorption data from water column, elutriates and zooplankton that demonstrate that lead biomagnifies at El Niágara reservoir, Mexico. Results include field data (bioaccumulation factors) (BAFs) and laboratory data (bioconcentration factors) (BCFs). Two findings: high BAFs for invertebrate predator like Acanthocyclops robustus, Asplanchna brightwellii, Culex sp. larvae, and Hyalella azteca, compared to grazer species Moina micrura and Simocephalus vetulus; low BCF’s found for some predators, suggested that lead biomagnifications were taking place. The presence of Moina micrura in the gut of Asplanchna allowed us to design experiments where A. brightwellii was fed lead-exposed M. micrura neonates. The BAF of Asplanchna was 123,684, BCF was 490. Asplanchna individuals fed exposed Moina had 13.31 times more lead than Asplanchna individuals just exposed 48-h to lead, confirming that lead biomagnification occurs. Results of two fish species showed no lead biomagnification, suggesting that lead biomagnification might be restricted to invertebrate predators.
显示更多 [+] 显示较少 [-]Cell size dependence of additive versus synergetic effects of UV radiation and PAHs on oceanic phytoplankton 全文
2011
Echeveste, Pedro | Agustí, Susana | Dachs, Jordi
Cell size dependence of additive versus synergetic effects of UV radiation and PAHs on oceanic phytoplankton 全文
2011
Echeveste, Pedro | Agustí, Susana | Dachs, Jordi
Polycyclic Aromatic Hydrocarbons’ (PAHs) toxicity is enhanced by the presence of ultraviolet radiation (UVR), which levels have arisen due to the thinning of the ozone layer. In this study, PAHs’ phototoxicity for natural marine phytoplankton was tested. Different concentrations of a mixture of 16 PAHs were added to natural phytoplankton communities from the Mediterranean Sea, Atlantic, Arctic and Southern Oceans and exposed to natural sunlight received in situ, including treatments where the UVR bands were removed. PAHs’ toxicity was observed for all the phytoplankton groups studied in all the waters and treatments tested, but only for the pico-sized group a synergetic effect of the mixture and UVR was observed (p=0.009). When comparing phototoxicity in phytoplankton from oligotrophic and eutrophic waters, synergy was only observed at the oligotrophic communities (p=0.02) where pico-sized phytoplankton dominated. The degree of sensitivity was related to the trophic degree, decreasing as Chlorophyll a concentration increased.
显示更多 [+] 显示较少 [-]Cell size dependence of additive versus synergetic effects of UV radiation and PAHs on oceanic phytoplankton 全文
2011
Echeveste, Pedro | Agustí, Susana | Dachs, Jordi
Polycyclic Aromatic Hydrocarbons' (PAHs) toxicity is enhanced by the presence of ultraviolet radiation (UVR), which levels have arisen due to the thinning of the ozone layer. In this study, PAHs' phototoxicity for natural marine phytoplankton was tested. Different concentrations of a mixture of 16 PAHs were added to natural phytoplankton communities from the Mediterranean Sea, Atlantic, Arctic and Southern Oceans and exposed to natural sunlight received in situ, including treatments where the UVR bands were removed. PAHs' toxicity was observed for all the phytoplankton groups studied in all the waters and treatments tested, but only for the pico-sized group a synergetic effect of the mixture and UVR was observed (p = 0.009). When comparing phototoxicity in phytoplankton from oligotrophic and eutrophic waters, synergy was only observed at the oligotrophic communities (p = 0.02) where pico-sized phytoplankton dominated. The degree of sensitivity was related to the trophic degree, decreasing as Chlorophyll a concentration increased. © 2011 Elsevier Ltd. All rights reserved. | Peer Reviewed
显示更多 [+] 显示较少 [-]Enhanced removal of pentachlorophenol by a novel composite: Nanoscale zero valent iron immobilized on organobentonite 全文
2011
Li, Yimin | Zhang, Yun | Li, Jianfa | Zheng, Xuming
Nanoscale zero valent iron (NZVI) was immobilized on the organobentonite (CTMA-bent), so as to enhance the reactivity of NZVI and prevent its aggregation. This novel composite (NZVI/CTMA-Bent) was characterized by transmission electron microscope and X-ray diffraction. Good dispersion of NZVI particles on the bentonite was observed. Its performance on removing pentachlorophenol (PCP) was investigated by batch experiments. Results showed NZVI/CTMA-Bent could rapidly and completely dechlorinate PCP to phenol with an efficiency of 96.2%. It was higher than the sum (54.5%) of reduction by NZVI (31.5%) and adsorption by CTMA-Bent (23.0%) separately. The kinetic studies indicated the removal rate of PCP was positively related to the adsorption. We proposed that the adsorption of PCP by CTMA-Bent enhanced the mass transfer of PCP from aqueous to iron surface. Besides, NZVI/CTMA-Bent exhibited good stability and reusability, and CTMA-Bent could also reduce the amount of iron ions released into the solution.
显示更多 [+] 显示较少 [-]Assessing estrogenic activity in surface water and sediment of the Liao River system in northeast China using combined chemical and biological tools 全文
2011
This paper investigated some selected estrogenic compounds (4-t-octylphenol: 4-t-OP; 4-nonylphenols: 4-NP; bisphenol-A: BPA; diethylstilbestrol: DES; estrone: E1; 17β-estradiol: E2; 17α-Ethinylestradiol: EE2; triclosan: TCS) and estrogenicity in the Liao River system using the combined chemical and in vitro yeast screen bioassay and assessed their ecological risks to aquatic organisms. The estrogenic compounds 4-t-OP, 4-NP, BPA, E1, E2 and TCS were detected in most of the samples, with their concentrations up to 52.1 2065.7, 755.6, 55.8, 7.4 and 81.3ng/L in water, and up to 8.6, 558.4, 33.8, 7.9, <LOQ and 33.9ng/g in sediment, respectively. However, DES and EE2 were not detected in the Liao River. The estrogen equivalents (EEQ) of the water and sediment samples were also measured by the bioassay. High estrogenic risks to aquatic organisms were found in the river sections of metropolitan areas and the lower reach of the river system.
显示更多 [+] 显示较少 [-]Contrasting effects of black carbon amendments on PAH bioaccumulation by Chironomus plumosus larvae in two distinct sediments: Role of water absorption and particle ingestion 全文
2011
Wang, Fan | Bu, Qingwei | Xia, Xinghui | Shen, Mohai
Two sediment matrices with different characteristics were amended with chars from different sources for bioaccumulation assay with filter-feeding Chironomus plumosus larvae. Chars greatly decreased porewater concentrations of PAHs (Cᵢw) measured using polyethylene devices in sediments. In organic rich sediment matrix-based systems where suspended char particles were absent, PAH concentrations in larvae (CᵢB) were significantly correlated with Cᵢw, and there was no difference in water-based bioaccumulation factors (BAFs) between different treatments, suggesting that water absorption was the main contaminant uptake route for larvae. In organic poor sediment matrix-based systems where suspended char particles were present, poor Pearson correlation between CᵢB and Cᵢw was found, but there was a significant linear increase of BAF values with char contents, which indicated that ingestion of suspended char particles could also be important for PAH bioaccumulation. Therefore, we need to rethink of the effectiveness and risks for the application of black carbon to sediment/soil remediation.
显示更多 [+] 显示较少 [-]Distribution and accumulation of endocrine-disrupting chemicals and pharmaceuticals in wastewater irrigated soils in Hebei, China 全文
2011
Chen, Feng | Ying, Guang-Guo | Kong, Ling-Xiao | Wang, Li | Zhao, Jian-Liang | Zhou, Li-Jun | Zhang, Li-Juan
This study investigated the occurrence of 43 emerging contaminants including 9 endocrine-disrupting chemicals and 34 pharmaceuticals in three sites in Hebei Province, north China. Each site has a wastewater irrigated plot and a separate groundwater irrigated plot for comparison purpose. The results showed that the concentrations of the target compounds in the wastewater irrigated soils were in most cases higher than those in the groundwater irrigated soils. Among the 43 target compounds, nine compounds bisphenol-A, triclocarban, triclosan, 4-nonylphenol, salicylic acid, oxytetracycline, tetracycline, trimethoprim and primidone were detected at least once in the soils. Preliminary environmental risk assessment showed that triclocarban might pose high risks to terrestrial organisms while the other detected compounds posed minimal risks. Irrigation with wastewater could lead to presence or accumulation of some emerging contaminants to some extent in irrigated soils.
显示更多 [+] 显示较少 [-]Effects of farm heterogeneity and methods for upscaling on modelled nitrogen losses in agricultural landscapes 全文
2011
Dalgaard, T. | Hutchings, N. | Dragosits, U. | Olesen, J.E. | Kjeldsen, C. | Drouet, J.L. | Cellier, P.
Effects of farm heterogeneity and methods for upscaling on modelled nitrogen losses in agricultural landscapes 全文
2011
Dalgaard, T. | Hutchings, N. | Dragosits, U. | Olesen, J.E. | Kjeldsen, C. | Drouet, J.L. | Cellier, P.
The aim of this study is to illustrate the importance of farm scale heterogeneity on nitrogen (N) losses in agricultural landscapes. Results are exemplified with a chain of N models calculating farm-N balances and distributing the N-surplus to N-losses (volatilisation, denitrification, leaching) and soil-N accumulation/release in a Danish landscape. Possible non-linearities in upscaling are assessed by comparing average model results based on (i) individual farm level calculations and (ii) averaged inputs at landscape level. Effects of the non-linearities that appear when scaling up from farm to landscape are demonstrated. Especially in relation to ammonia losses the non-linearity between livestock density and N-loss is significant (p > 0.999), with around 20–30% difference compared to a scaling procedure not taking this non-linearity into account. A significant effect of farm type on soil N accumulation (p > 0.95) was also identified and needs to be included when modelling landscape level N-fluxes and greenhouse gas emissions.
显示更多 [+] 显示较少 [-]Effects of farm heterogeneity and methods for upscaling on modelled nitrogen losses in agricultural landscapes 全文
2011
Dalgaard, T., T. | Hutchings, N., N. | Dragosits, U., U. | Olesen, J.E., J.E. | Kjeldsen, C., C. | Drouet, Jean-Louis | Cellier, Pierre, P. | Department of Agroecology ; Aarhus University [Aarhus] | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech
no sp. Assessment of Nitrogen Fluxes to Air and Water from Site Scale to Continental Scale | The aim of this study is to illustrate the importance of farm scale heterogeneity on nitrogen (N) losses in agricultural landscapes. Results are exemplified with a chain of N models calculating farm-N balances and distributing the N-surplus to N-losses (volatilisation, denitrification, leaching) and soil-N accumulation/release in a Danish landscape. Possible non-linearities in upscaling are assessed by comparing average model results based on (i) individual farm level calculations and (ii) averaged inputs at landscape level. Effects of the non-linearities that appear when scaling up from farm to landscape are demonstrated. Especially in relation to ammonia losses the non-linearity between livestock density and N-loss is significant (p > 0.999), with around 20-30% difference compared to a scaling procedure not taking this non-linearity into account. A significant effect of farm type on soil N accumulation (p > 0.95) was also identified and needs to be included when modelling landscape level N-fluxes and greenhouse gas emissions.
显示更多 [+] 显示较少 [-]Effects of farm heterogeneity and methods for upscaling on modelled nitrogen losses in agricultural landscapes 全文
2011
Dalgaard, Tommy | Hutchings, Nicholas J. | Dragosits, U. | Olesen, J.E. | Kjeldsen, Chris | Drouet, J.L. | Cellier, P.
The aim of this study is to illustrate the importance of farm scale heterogeneity on nitrogen (N) losses in agricultural landscapes. Results are exemplified with a chain of N models calculating farm-N balances and distributing the N-surplus to N-losses (volatilisation, denitrification, leaching) and soil-N accumulation/release in a Danish landscape. Possible non-linearities in upscaling are assessed by comparing average model results based on (i) individual farm level calculations and (ii) averaged inputs at landscape level. Effects of the non-linearities that appear when scaling up from farm to landscape are demonstrated. Especially in relation to ammonia losses the non-linearity between livestock density and N-loss is significant (p > 0.999), with around 20-30% difference compared to a scaling procedure not taking this non-linearity into account. A significant effect of farm type on soil N accumulation (p > 0.95) was also identified and needs to be included when modelling landscape level N-fluxes and greenhouse gas emissions.
显示更多 [+] 显示较少 [-]Effects of farm heterogeneity and methods for upscaling on modelled nitrogen losses in agricultural landscapes 全文
2011
Dalgaard, T., T. | Hutchings, N., N. | Dragosits, U., U. | Olesen, J.E., J.E. | Kjeldsen, C., C. | Drouet, Jean-Louis | Cellier, Pierre, P. | Department of Agroecology ; Aarhus University [Aarhus] | Environnement et Grandes Cultures (EGC) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech
no sp. Assessment of Nitrogen Fluxes to Air and Water from Site Scale to Continental Scale | The aim of this study is to illustrate the importance of farm scale heterogeneity on nitrogen (N) losses in agricultural landscapes. Results are exemplified with a chain of N models calculating farm-N balances and distributing the N-surplus to N-losses (volatilisation, denitrification, leaching) and soil-N accumulation/release in a Danish landscape. Possible non-linearities in upscaling are assessed by comparing average model results based on (i) individual farm level calculations and (ii) averaged inputs at landscape level. Effects of the non-linearities that appear when scaling up from farm to landscape are demonstrated. Especially in relation to ammonia losses the non-linearity between livestock density and N-loss is significant (p > 0.999), with around 20-30% difference compared to a scaling procedure not taking this non-linearity into account. A significant effect of farm type on soil N accumulation (p > 0.95) was also identified and needs to be included when modelling landscape level N-fluxes and greenhouse gas emissions.
显示更多 [+] 显示较少 [-]Interspecies and spatial trends in polycyclic aromatic hydrocarbons (PAHs) in Atlantic and Mediterranean pelagic seabirds 全文
2011
Roscales, Jose L. | González-Solís, Jacob | Calabuig, Pascual | Jiménez, Begoña
PAHs were analyzed in the liver of 5 species of pelagic seabirds (Procellariiformes) from the northeast Atlantic and the Mediterranean. The main objective was to assess the trophic and geographic trends of PAHs in seabirds to evaluate their suitability as bioindicators of chronic marine pollution by these compounds. Although higher levels of PAHs have been described in the Mediterranean compared to other oceanic regions, we did not find significant spatial patterns and observed only minor effects of the geographic origin on seabird PAHs. However, we found significant higher PAH levels in petrel compared to shearwater species, which could be related to differences in their exploitation of mesopelagic and epipelagic resources, respectively, and the vertical dynamic of PAHs in the water column. Overall, although this study enhances the need of multi-species approaches to show a more comprehensive evaluation of marine pollution, seabirds emerged as poor indicators of pelagic chronic PAH levels.
显示更多 [+] 显示较少 [-]Organochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation 全文
2011
Coat, Sophie | Monti, Dominique | Legendre, Pierre | Bouchon, Claude | Massat, Félix | Lepoint, Gilles
Organochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation 全文
2011
Coat, Sophie | Monti, Dominique | Legendre, Pierre | Bouchon, Claude | Massat, Félix | Lepoint, Gilles
Concentrations of organochlorine pesticides and stable isotope ratios of nitrogen and carbon were measured in a tropical freshwater ecosystem to evaluate the contamination level of biota and examine the bioaccumulation patterns of pollutants through the food web. Chemical analyses showed a general and heavy contamination of the entire food web. They revealed the strong accumulation of pollutants by juveniles of diadromous fishes and shrimps, as they re-enter the river. The role of ecological factors in the bioaccumulation of pesticides was evaluated. Whereas the most persistent pollutants (chlordecone and monohydro-chlordecone) were related to the organisms diet and habitat, bioaccumulation of β-HCH was only influenced by animal lipid content. The biomagnification potential of chlordecone through the food chain has been demonstrated. It highlighted the importance of trophic transfer in this compound bioaccumulation process. In contrast, bioconcentration by passive diffusion from water seemed to be the main exposure route of biota to β-HCH.
显示更多 [+] 显示较少 [-]Organochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation 全文
2011
Coat, Sophie | Monti, Dominique | Legendre, Pierre | Bouchon, Claude | Massat, Félix | Lepoint, Gilles
Direction Régionale de l’Environnement de la Guadeloupe | Centre Interfacultaire de Recherches en Océanologie - MARE | Concentrations of organochlorine pesticides and stable isotope ratios of nitrogen and carbon weremeasured in a tropical freshwater ecosystem to evaluate the contamination level of biota and examinethe bioaccumulation patterns of pollutants through the food web. Chemical analyses showed a generaland heavy contamination of the entire food web. They revealed the strong accumulation of pollutants byjuveniles of diadromous fishes and shrimps, as they re-enter the river. The role of ecological factors in thebioaccumulation of pesticides was evaluated. Whereas the most persistent pollutants (chlordecone andmonohydro-chlordecone) were related to the organisms diet and habitat, bioaccumulation of b-HCH wasonly influenced by animal lipid content. The biomagnification potential of chlordecone through the foodchain has been demonstrated. It highlighted the importance of trophic transfer in this compound bioaccumulationprocess. In contrast, bioconcentration by passive diffusion from water seemed to be themain exposure route of biota to b-HCH. | Linked papers: Coat et al. 2009 and Lefrançois et al. 2010
显示更多 [+] 显示较少 [-]Organochlorine pollution in tropical rivers (Guadeloupe): Role of ecological factors in food web bioaccumulation 全文
2011
Coat, Sophie | Monti, Dominique | Legendre, Pierre | Bouchon, Claude | Massat, Félix | Lepoint, Gilles | MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège | Dynecar - Université Antilles Guyane
peer reviewed | Concentrations of organochlorine pesticides and stable isotope ratios of nitrogen and carbon were measured in a tropical freshwater ecosystem to evaluate the contamination level of biota and examine the bioaccumulation patterns of pollutants through the food web. Chemical analyses showed a general and heavy contamination of the entire food web. They revealed the strong accumulation of pollutants by juveniles of diadromous fishes and shrimps, as they re-enter the river. The role of ecological factors in the bioaccumulation of pesticides was evaluated. Whereas the most persistent pollutants (chlordecone and monohydro-chlordecone) were related to the organisms diet and habitat, bioaccumulation of b-HCH was only influenced by animal lipid content. The biomagnification potential of chlordecone through the food chain has been demonstrated. It highlighted the importance of trophic transfer in this compound bioaccumulation process. In contrast, bioconcentration by passive diffusion from water seemed to be the main exposure route of biota to b-HCH.
显示更多 [+] 显示较少 [-]Influence of fly ash aided phytostabilisation of Pb, Cd and Zn highly contaminated soils on Lolium perenne and Trifolium repens metal transfer and physiological stress 全文
2011
Lopareva-Pohu, Alena | Verdin, Anthony | Garçon, Guillaume | Lounès-Hadj Sahraoui, Anissa | Pourrut, Bertrand | Debiane, Djouher | Waterlot, Christophe | Laruelle, Frédéric | Bidar, Géraldine | Douay, Francis | Shirali, Pirouz
Due to anthropogenic activities, large extends of soils are highly contaminated by Metal Trace Element (MTE). Aided phytostabilisation aims to establish a vegetation cover in order to promote in situ immobilisation of trace elements by combining the use of metal-tolerant plants and inexpensive mineral or organic soil amendments. Eight years after Coal Fly Ash (CFA) soil amendment, MTE bioavailability and uptake by two plants, Lolium perenne and Trifolium repens, were evaluated, as some biological markers reflecting physiological stress. Results showed that the two plant species under study were suitable to reduce the mobility and the availability of these elements. Moreover, the plant growth was better on CFA amended MTE-contaminated soils, and the plant sensitivity to MTE-induced physiological stress, as studied through photosynthetic pigment contents and oxidative damage was lower or similar. In conclusion, these results supported the usefulness of aided phytostabilisation of MTE-highly contaminated soils.
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