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Chemical stability of metallic nanoparticles: A parameter controlling their potential cellular toxicity in vitro Full text
2009
Auffan, Mélanie | Rose, Jerome | Wiesner, Mark R. | Bottero, Jean-Yves
Chemical stability of metallic nanoparticles: A parameter controlling their potential cellular toxicity in vitro Full text
2009
Auffan, Mélanie | Rose, Jerome | Wiesner, Mark R. | Bottero, Jean-Yves
The level of production of nanoparticles will inevitably lead to their appearance in air, water, soils, and organisms. A theoretical framework that relates properties of nanoparticles to their biological effects is needed to identify possible risks to human health and the environment. This paper considers the properties of dispersed metallic nanoparticles and highlights the relationship between the chemical stability of these nanoparticles and their in vitro toxicity. Analysis of published data suggests that chemically stable metallic nanoparticles have no significant cellular toxicity, whereas nanoparticles able to be oxidized, reduced or dissolved are cytotoxic and even genotoxic for cellular organisms. The ability of metallic nanoparticles to be oxidized, reduced or dissolved in biological media can be used to predict their toxicity in vitro.
Show more [+] Less [-]Chemical stability of metallic nanoparticles: A parameter controlling their potential cellular toxicity in vitro Full text
2009
Auffan, Melanie | Rose, Jérôme | Wiesner, Mark, R | Bottero, Jean-Yves | Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE) ; Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) | Duke University [Durham]
International audience | The ability of metallic nanoparticles to be oxidized, reduced or dissolved in biological media can be used to predict their toxicity in vitro. a b s t r a c t The level of production of nanoparticles will inevitably lead to their appearance in air, water, soils, and organisms. A theoretical framework that relates properties of nanoparticles to their biological effects is needed to identify possible risks to human health and the environment. This paper considers the properties of dispersed metallic nanoparticles and highlights the relationship between the chemical stability of these nanoparticles and their in vitro toxicity. Analysis of published data suggests that chemically stable metallic nanoparticles have no significant cellular toxicity, whereas nanoparticles able to be oxidized, reduced or dissolved are cytotoxic and even genotoxic for cellular organisms.
Show more [+] Less [-]Polycyclic aromatic hydrocarbon (PAH) contamination of surface sediments and oysters from the inter-tidal areas of Dar es Salaam, Tanzania Full text
2009
Gaspare, Lydia | Machiwa, John F. | Mdachi, S.J.M. | Streck, Georg | Brack, Werner
Surface sediment and oyster samples from the inter-tidal areas of Dar es Salaam were analyzed for 23 polycyclic aromatic hydrocarbons (PAHs) including the 16 compounds prioritized by US-EPA using GC/MS. The total concentration of PAHs in the sediment ranged from 78 to 25,000 ng/g dry weight, while oyster concentrations ranged from 170 to 650 ng/g dry weight. Hazards due to sediment contamination were assessed using Equilibrium Partitioning Sediment Benchmarks and Threshold Effect Levels. Diagnostic indices and principle component analysis were used to identify possible sources. Interestingly, no correlation between sediment and oyster concentrations at the same sites was found. This is supported by completely different contamination patterns, suggesting different sources for both matrices. Hazard assessment revealed possible effects at six out of eight sites on the benthic communities and oyster populations. The contribution of PAH intake via oyster consumption to carcinogenic risks in humans seems to be low. PAH contamination may pose hazards to benthos but limited risks to humans
Show more [+] Less [-]Glutathione transferase (GST) as a candidate molecular-based biomarker for soil toxin exposure in the earthworm Lumbricus rubellus Full text
2009
LaCourse, E James | Hernandez-Viadel, Mariluz | Jefferies, James R. | Svendsen, Claus | Spurgeon, David J. | Barrett, John | Morgan, A John | Kille, Peter | Brophy, Peter M.
The earthworm Lumbricus rubellus (Hoffmeister, 1843) is a terrestrial pollution sentinel. Enzyme activity and transcription of phase II detoxification superfamily glutathione transferases (GST) is known to respond in earthworms after soil toxin exposure, suggesting GST as a candidate molecular-based pollution biomarker. This study combined sub-proteomics, bioinformatics and biochemical assay to characterise the L. rubellus GST complement as pre-requisite to initialise assessment of the applicability of GST as a biomarker. L. rubellus possesses a range of GSTs related to known classes, with evidence of tissue-specific synthesis. Two affinity-purified GSTs dominating GST protein synthesis (Sigma and Pi class) were cloned, expressed and characterised for enzyme activity with various substrates. Electrospray ionisation mass spectrometry (ESI-MS) and tandem mass spectrometry (MS/MS) following SDS-PAGE were superior in retaining subunit stability relative to two-dimensional gel electrophoresis (2-DE). This study provides greater understanding of Phase II detoxification GST superfamily status of an important environmental pollution sentinel organism. This study currently provides the most comprehensive view of the Phase II detoxification enzyme superfamily of glutathione transferases within the important environmental pollution sentinel earthworm Lumbricus rubellus.
Show more [+] Less [-]Fate of linear alkylbenzenes and benzothiazoles of anthropogenic origin and their potential as environmental molecular markers in the Pearl River Delta, South China Full text
2009
Ni, Hong-Gang | Shen, Ru-Lang | Zeng, Hui | Zeng, E. Y. (Eddy Y)
The mass emissions of linear alkylbenzenes (LABs), benzothiazole (BT), and 2-[4-morpholinyl]benzothiazole (24MoBT) from anthropogenic activities within one year were estimated according to the population and the number of automobiles in the Pearl River Delta (PRD), South China. Based on the estimation, the distribution of these compounds among various environmental media was simulated with a mass balance box model established in the present study. The results showed that 79% of LABs generated in the PRD was stored in sediment while only 1.3% of LABs was presumably transported to the adjacent South China Sea (SCS). On the contrary, 47% of BT and 77% of 24MoBT generated in the region were carried with riverine runoff to the coastal ocean. The results from the present study suggest that hydrophobic compounds tend to stay in the watershed of the PRD, whereas hydrophilic ones mainly outflow to the coastal ocean. A simple mass balance box model examines the fate of linear alkylbenzenes and benzothiazoles in the Pearl River Delta, South China.
Show more [+] Less [-]Long-term air monitoring of organochlorine pesticides using Semi Permeable Membrane Devices (SPMDs) in the Alps Full text
2009
Levy, W. | Henkelmann, B. | Pfister, G. | Bernhöft, S. | Kirchner, M. | Jakobi, G. | Bassan, R. | Kräuchi, N. | Schramm, K.W.
Atmospheric sampling of organochlorine pesticides (OCPs) was conducted using Semi Permeable Membrane Devices (SPMDs) deployed in the Alps at different altitudinal transects for two consecutive exposure periods of half a year and a third simultaneous year-long period. Along all the altitude profiles, the sequestered amounts of OCPs increased in general with altitude. SPMDs were still working as kinetic samplers after half a year for the majority of the OCPs. However, compounds with the lowest octanol-air partition coefficient (Koa), reached equilibrium within six months. This change in the SPMD uptake was determined for the temperature gradient along the altitude profile influencing Koa, OCPs availability in the gaseous phase, and SPMD performance. In sum, it seems two effects are working in parallel along the altitude profiles: the change in SPMD performance and the different availability of OCPs along the altitudinal transects determined by their compound properties and concentrations in air. SPMDs were in different uptake stages regarding OCPs, as they were influenced by the temperature (season, triolein state, and altitude) and Koa.
Show more [+] Less [-]Soil burdens of persistent organic pollutants – Their levels, fate and risk. Part I. Variation of concentration ranges according to different soil uses and locations Full text
2009
Holoubek, Ivan | Dušek, Ladislav | Sáňka, Milan | Hofman, Jakub | Čupr, Pavel | Jarkovský, Jiří | Zbíral, Jiří | Klánová, Jana
Detailed soil screening data from the Czech Republic as a typical Central European country are presented here. Determination of a wide selection of organic and inorganic pollutants as well as an assessment of specific soil parameters allowed us to study the soil contamination in relation to the land use and soil properties. While HCHs and HCB were found at highest levels in arable soils, the higher concentrations of PCDDs/Fs, PCBs, PAHs and DDTs were observed in high altitude forest soils. Concentrations of these compounds strongly correlated with the soil organic carbon content. Several possible reasons have been suggested for the observed higher concentrations in mountain forest soils but the impact of each of these influencing factors remains to be identified. An inventory of the soil contamination is needed as a first step in our effort to estimate an extent to which the secondary sources contribute to the enhanced atmospheric levels of POPs. Due to its large retention capacity for hydrophobic compounds, carbon-rich mountain soil showed higher concentrations for several persistent organic pollutants.
Show more [+] Less [-]Behavior of damselfly larvae (Enallagma cyathigerum) (Insecta, Odonata) after long-term exposure to PFOS Full text
2009
Gossum, Hans van | Bots, Jessica | Snijkers, Tom | Meyer, Johan | Wassenbergh, Sam Van | Coen, Wim De | Bruyn, Luc de
Perfluorooctane sulfonic acid (PFOS) is a persistent and ubiquitous environmental contaminant that has been detected in organisms worldwide. Here, we evaluate whether long-term (1 and 4 months) exposure to PFOS contamination affects the behavioural performance of freshwater larvae of the damselfly Enallagma cyathigerum (Insecta: Odonata). Our results show reduced behavioural performance with increasing PFOS concentration. In 1 month exposed larvae, no observed effect concentrations (NOECs) were 100 μg/L for general activity. In 4 months exposed larvae, NOECs were 10 μg/L, for each behavioural trait, except swimming acceleration of male larvae where the NOEC was 100 μg/L. When faced with PFOS concentrations above the NOEC, E. cyathigerum larvae were less active, less capable to escape a simulated predator attack and less efficient in foraging. Together, our results show that damselfly larvae suffer reduced survival-related behavioural performance. Long-term laboratory exposure to perfluorooctane sulfonic acid decreases behavioural performance of damselfly larvae (Insecta: Odonata).
Show more [+] Less [-]Comparison of manufactured and black carbon nanoparticle concentrations in aquatic sediments Full text
2009
Koelmans, A.A. | Nowack, B. | Wiesner, M.R.
In this paper, we show that concentrations of manufactured carbon-based nanoparticles (MCNPs) in aquatic sediments will be negligible compared to levels of black carbon nanoparticles (BCNPs). This is concluded from model calculations accounting for MCNP sedimentation fluxes, removal rates due to aggregation or degradation, and MCNP burial in deeper sediment layers. The resultant steady state MCNP levels are compared with BCNP levels calculated from soot levels in sediments and weight fractions of nanosized fractions of these soot particles. MCNP/BCNP ratios range from 10-7 to 10-4 (w:w). This suggests that the often acclaimed effect of MCNPs on organic pollutant binding and bioavailability will likely be below the level of detection if natural BCNPs are present, even if binding to MCNP is one to two orders of magnitude stronger than to BCNPs. Furthermore, exposure and toxic effects of MCNPs in sediments and soils will be negligible compared to that of BCNPs. Concentrations of manufactured carbon-based nanoparticles in sediments and soils will be negligible compared to levels of black carbon (soot) nanoparticles.
Show more [+] Less [-]Correlations between physicochemical properties of PAHs and their distribution in soil, moss and reindeer dung at Ny-Alesund of the Arctic Full text
2009
Wang, Zhen | Ma, Xindong | Na, Guangshui | Lin, Zhongsheng | Ding, Qian | Yao, Ziwei
Concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in soil, moss and reindeer dung collected at Ny-Ålesund of the Arctic were measured to investigate their accumulation trends and distribution in the three compartments. Compared with the other regions, the proportions of 2 + 3 ring PAHs to the total PAHs were higher, whereas the proportions of 5 + 6 ring PAHs were lower in the three compartments at Ny-Ålesund. Significant log/log-linear relationship was observed between the sub-cooled liquid vapor pressure View the MathML source and the soil/moss quotient (QSM). The relation was similar to the relationship between the gas/particle partition coefficient (KP) and View the MathML source of PAHs, implying QSM would be a “mirror image” of KP. Excellent log/log-linear relationships were observed between QSM and KOA as well as between the moss/dung quotient (QMD) and KOW. The results presented here indicate the physicochemical properties are suitable for characterizing the distribution of PAHs in soil, moss and reindeer dung. The physicochemical properties of PAHs are suitable for characterizing their distribution in soil, moss and reindeer dung.
Show more [+] Less [-]VOC in an urban and industrial harbor on the French North Sea coast during two contrasted meteorological situations Full text
2009
Roukos, Joelle | Riffault, Véronique | Locoge, Nadine | Plaisance, Hervé
Two measurement campaigns of volatile organic compounds (VOC) were carried out in the industrial city of Dunkerque, using Radiello passive samplers during winter (16-23 January) and summer (6-13 June) 2007. 174 compounds were identified belonging to six chemical families. Classifying sampling sites with similar chemical profiles by hierarchical ascending classification resulted in 4 groups that reflected the influence of the main industrial and urban sources of pollution. Also, the BTEX (Benzene, Toluene, Ethylbenzene and Xylenes) quantification allowed us to map their levels of concentration. Benzene and toluene (BT) showed high concentrations in Northern Dunkerque reflecting the influence of two industrial plants. Differences among spatial distributions of the BT concentrations over contrasted meteorological conditions were also observed. An atypical ratio of T/B in the summer samples led us to investigate the BTEX origins shedding light on the contribution of pollutants transported across various zones of VOC emissions situated in Europe. This study was devoted for screening of VOC and investigation of local and regional source contributions to BTEX concentration in a French industrialized harbor.
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