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Levels and distribution of dissolved hydrophobic organic contaminants in the Morava river in Zlín district, Czech Republic as derived from their accumulation in silicone rubber passive samplers
2012
Prokeš, Roman | Vrana, Branislav | Klánová, Jana
Dissolved waterborne polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed over a period of one year at five sampling sites in a model industrial region in the Czech Republic using silicone rubber passive samplers. The spatial variability of POPs in the studied region in water was small and diffusive pollution sources predominate. Concentrations of the most volatile PAHs decreased with increasing water temperature in the whole region, which reflects the seasonality in atmospheric deposition. The dissolved concentrations of more hydrophobic PAHs, PCBs and OCPs in and downstream the industrial zone are related to desorption from suspended particles. Upstream the industrial area, a positive correlation of dissolved and particle-bound contamination was observed only for DDT metabolites and hexachlorobenzene. Calculated fugacities in water and bottom sediment indicated a fair degree of equilibrium between these compartments for OCPs and PCBs, whereas sediment represented a potential source of PAHs.
Afficher plus [+] Moins [-]Induction of mouthpart deformities in chironomid larvae exposed to contaminated sediments
2012
Di Veroli, Alessandra | Goretti, Enzo | Paumen, Miriam Leόn | Kraak, Michiel H.S. | Admiraal, Wim
The aim of the present study was to improve the cause–effect relationship between toxicant exposure and chironomid mouthpart deformities, by linking induction of mouthpart deformities to contaminated field sediments, metal mixtures and a mutagenic polycyclic aromatic compound metabolite (acridone). Mouthpart deformities in Chironomus riparius larvae were induced by both the heavy metal mixture and by acridone. A clear correlation between metal concentrations in the sediment and deformities incidence was only observed when the contaminated field sediments were left out of the analysis, probably because these natural sediments contained other toxic compounds, which could be responsible for a higher incidence of deformities than predicted by the measured metal concentrations only. The present study clearly improved the cause–effect relationship between toxicant exposure and the induction of mouthpart deformities. It is concluded that the incidence of mouthpart deformities may better reflect the potential toxicity of contaminated sediments than chemical analysis.
Afficher plus [+] Moins [-]Dechlorination of p,p′-DDTs coupled with sulfate reduction by novel sulfate-reducing bacterium Clostridium sp. BXM
2012
Bao, Peng | Hu, Zheng-Yi | Wang, Xin-Jun | Chen, Jian | Ba, Yu-Xin | Hua, Jing | Zhu, Chun-You | Zhong, Min | Wu, Chun-Yan
A novel non-dsrAB (without dissimilatory sulfite reductase genes) sulfate-reducing bacterium (SRB) Clostridium sp. BXM was isolated from a paddy soil. Incubation experiments were then performed to investigate the formation of reduced sulfur compounds (RSC) by Clostridium sp. BXM, and RSC-induced dechlorination of p,p′-DDT in culture medium and soil solution. The RSCs produced were 5.8mM and 4.5mM in 28mM sulfate amended medium and soil solution respectively after 28-day cultivation. The p,p′-DDT dechlorination ratios were 74% and 45.8% for 5.8mM and 4.5mM RSCs respectively at 6h. The metabolites of p,p′-DDT found in the two reaction systems were identified as p,p′-DDD and p,p′-DDE. The dechlorination pathways of p,p′-DDT to p,p′-DDD and p,p′-DDE were proposed, based on mass balance and dechlorination time-courses. The results indicated that RSC-induced natural dechlorination may play an important role in the fate of organochlorines.
Afficher plus [+] Moins [-]High nitrogen and elevated [CO₂] effects on the growth, defense and photosynthetic performance of two eucalypt species
2012
Novriyanti, Eka | Watanabe, Makoto | Kitao, Mitsutoshi | Utsugi, Hajime | Uemura, Akira | Koike, Takayoshi
Atmospheric nitrogen deposition and [CO₂] are increasing and represent environmental problems. Planting fast-growing species is prospering to moderate these environmental impacts by fixing CO₂. Therefore, we examined the responses of growth, photosynthesis, and defense chemical in leaves of Eucalyptus urophylla (U) and the hybrid of E. deglupta × E. camadulensis (H) to different CO₂ and nitrogen levels. High nitrogen load significantly increased plant growth, leaf N, net photosynthetic rate (Agᵣₒwₜₕ), and photosynthetic water use efficiency (WUE). High CO₂ significantly increased Agᵣₒwₜₕ, photosynthetic nitrogen use efficiency (PNUE) and WUE. Secondary metabolite (SM, i.e. total phenolics and condensed tannin) was specifically altered; as SM of U increased by high N load but not by elevated [CO₂], and vice versa for SM of H.
Afficher plus [+] Moins [-]Regional variation and possible sources of brominated contaminants in breast milk from Japan
2012
Fujii, Yukiko | Ito, Yoshiko | Harada, Kouji H. | Hitomi, Toshiaki | Koizumi, Akio | Haraguchi, Koichi
This study focuses on the regional trends and possible sources of brominated organic contaminants accumulated in breast milk from mothers in southeastern (Okinawa) and northwestern (Hokkaido) areas of Japan. For persistent brominated flame retardants, polybrominated diphenyl ethers (PBDEs; major components, BDE-47 and BDE-153) were distributed at higher levels in mothers from Okinawa (mean, 2.1 ng/g lipid), while hexabromobenzene (HeBB) and its metabolite 1,2,4,5-tetrabromobenzene were more abundantly detected in mothers from Hokkaido (0.86 and 2.6 ng/g lipid), suggesting that there are regional differences in their exposure in Japan. We also detected naturally produced brominated compounds, one of which was identified as 2′-methoxy-2,3′,4,5′-tetrabromodiphenyl ether (2′-MeO-BDE68) at higher levels in mothers from Okinawa (0.39 ng/g lipid), while the other was identified as 3,3′,4,4′-tetrabromo-5,5′-dichloro-2,2′-dimethyl-1,1′-bipyrrole in mothers from Hokkaido (0.45 ng/g lipid). The regional variation may be caused by source differences, i.e. southern seafood for MeO-PBDEs and northern biota for halogenated bipyrroles in the Japanese coastal water.
Afficher plus [+] Moins [-]Removal of the antiviral agent oseltamivir and its biological activity by oxidative processes
2012
Mestankova, Hana | Schirmer, Kristin | Escher, Beate I. | von Gunten, Urs | Canonica, Silvio
The antiviral agent oseltamivir acid (OA, the active metabolite of Tamiflu®) may occur at high concentrations in wastewater during pandemic influenza events. To eliminate OA and its antiviral activity from wastewater, ozonation and advanced oxidation processes were investigated. For circumneutral pH, kinetic measurements yielded second-order rate constants of 1.7 ± 0.1 × 10⁵ and 4.7 ± 0.2 × 10⁹ M⁻¹ s⁻¹ for the reaction of OA with ozone and hydroxyl radical, respectively. During the degradation of OA by both oxidants, the antiviral activity of the treated aqueous solutions was measured by inhibition of neuraminidase activity of two different viral strains. A transient, moderate (two-fold) increase in antiviral activity was observed in solutions treated up to a level of 50% OA transformation, while for higher degrees of transformation the activity corresponded to that caused exclusively by OA. OA was efficiently removed by ozonation in a wastewater treatment plant effluent, suggesting that ozonation can be applied to remove OA from wastewater.
Afficher plus [+] Moins [-]Long-term persistence of various ¹⁴C-labeled pesticides in soils
2012
Jablonowski, Nicolai D. | Linden, Andreas | Köppchen, Stephan | Thiele, Björn | Hofmann, Diana | Mittelstaedt, Werner | Pütz, Thomas | Burauel, Peter
The fate of the ¹⁴C-labeled herbicides ethidimuron (ETD), methabenzthiazuron (MBT), and the fungicide anilazine (ANI) in soils was evaluated after long-term aging (9–17 years) in field based lysimeters subject to crop rotation. Analysis of residual ¹⁴C activity in the soils revealed 19% (ETD soil; 0–10 cm depth), 35% (MBT soil; 0–30), and 43% (ANI soil; 0–30) of the total initially applied. Accelerated solvent extraction yielded 90% (ETD soil), 26% (MBT soil), and 41% (ANI soil) of residual pesticide ¹⁴C activity in the samples. LC-MS/MS analysis revealed the parent compounds ETD and MBT, accounting for 3% and 2% of applied active ingredient in the soil layer, as well as dihydroxy-anilazine as the primary ANI metabolite. The results for ETD and MBT were matching with values obtained from samples of a 12 year old field plot experiment. The data demonstrate the long-term persistence of these pesticides in soils based on outdoor trials.
Afficher plus [+] Moins [-]Occurrence and persistence of organic emerging contaminants and priority pollutants in five sewage treatment plants of Spain: Two years pilot survey monitoring
2012
Bueno, M.J Martínez | Gomez, M.J. | Herrera, S. | Hernando, M.D. | Agüera, A. | Fernández-Alba, A.R.
This work summarized all results obtained during almost two-years of a monitoring programme carried out in five municipal sewage treatment plants (STPs) located in the north, centre and south-east of Spain. The study evaluated the occurrence and persistence of a group of 100 organic compounds belonging to several chemical groups (pharmaceuticals, personal care products, pesticides and metabolites). The average removal efficiencies of the STPs studied varied from 20% (erythromycin) to 99% (acetaminophen). In analysed samples, we identified a large number of compounds at mean range concentrations between 7–59,495 ng/L and 5–32,720 ng/L for influent and effluent samples, respectively. This study also identified 20 of the mostly detected and persistent compounds in wastewater effluent, of which hydrochlorothiazide, atenolol, gemfibrozil, galaxolide and three metabolites (fenofibric acid, 4-AAA and 4-FAA), presented the highest average contribution percentages, in relation to the total load of contaminants for the different STPs effluent studied.
Afficher plus [+] Moins [-]Increased levels of 8-hydroxy-2′-deoxyguanosine are attributable to organophosphate pesticide exposure among young children
2012
Ding, Guodong | Han, Song | Wang, Pei | Gao, Yu | Shi, Rong | Wang, Guoquan | Tian, Ying
Oxidative damage has been proposed as an important mechanism linking pesticide exposure to health effects. A study of 268 young Shanghai children was conducted to examine the relationship between organophosphate pesticide (OP) exposure and a biomarker of oxidative DNA damage. Urine samples were analyzed for five nonspecific dialkyl phosphate (DAP) metabolites [dimethyl phosphates (DMs) and diethyl phosphates (DEs)] and 8-hydroxy-2′-deoxyguanosine (8-OHdG). The creatinine-adjusted median of 8-OHdG in urine samples was 3.99ng/mg. Increased exposure to OPs was associated with greater levels of urinary 8-OHdG [total DAPs: ß (adjusted)=0.46 per log₁₀ unit increase, 95% confidence interval (CI)=0.40–0.53, p=0.000; DMs: ß (adjusted)=0.34, 95% CI=0.28–0.41, p=0.000; DEs: ß (adjusted)=0.48, 95% CI=0.42–0.54, p=0.000]. Thus, the 8-OHdG biomarker is useful for increasing our understanding of the link between childhood exposure to OPs and health outcomes.
Afficher plus [+] Moins [-]Biomarker responses in Atlantic cod (Gadus morhua) exposed to produced water from a North Sea oil field: Laboratory and field assessments
2012
Sundt, Rolf C. | Ruus, Anders | Jonsson, Henrik | Skarphéðinsdóttir, Halldóra | Meier, Sonnich | Grung, Merete | Beyer, Jonny | Pampanin, Daniela M.
Biological markers of produced water (PW) exposure were studied in Atlantic cod (Gadus morhua) in both laboratory and field experiments, using authentic PW from a North Sea oil field. In the laboratory study, the PW exposure yielded significantly elevated levels of metabolites of polycyclic aromatic hydrocarbons (PAHs) and alkylphenols (APs) in bile even at the lowest exposure dose (0.125% PW). Other biomarkers (hepatic CYP1A induction and DNA adduct formation) responded at 0.25% and 0.5% PW concentrations. In the field study, bile metabolite markers and hepatic CYP1A were clearly increased in fish caged close to the PW outfall. Induction of plasma vitellogenin was not found in laboratory or field exposures, suggesting that the levels of oestrogen agonists (such as APs) might not have been sufficient to elicit induction, under the present conditions. The applicability of the biomarkers for use in water column biomonitoring programs is discussed.
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