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Lead concentration increase in the hepatic and gill soluble fractions of European chub (Squalius cephalus)—an indicator of increased Pb exposure from the river water Full text
2012
Dragun, Zrinka | Krasnići, Nesrete | Strižak, Željka | Raspor, Biserka
PURPOSE: To examine if chronic exposure of feral fish to elevated Pb concentrations in the river water (up to 1 μg L−1), which are still lower than European recommendations for dissolved Pb in surface waters (7.2 μg L−1; EPCEU (Official J L 348:84, 2008)), would result in Pb accumulation in selected fish tissues. METHODS: Lead concentrations were determined by use of HR ICP-MS in the gill and hepatic soluble fractions of European chub (Squalius cephalus) caught in the Sutla River (Croatia–Slovenia). RESULTS: At the site with increased dissolved Pb in the river water, soluble gill Pb levels (17.3 μg L−1) were approximately 20 times higher compared to uncontaminated sites (0.85 μg L−1), whereas the ratio between contaminated (18.1 μg L−1) and uncontaminated sites (1.17 μg L−1) was lower for liver (15.5). Physiological variability of basal Pb concentrations in soluble gill and hepatic fractions associated to fish size, condition, sex, or age was not observed, excluding the possibility that Pb increase in chub tissues at contaminated site could be the consequence of studied biotic parameters. However, in both tissues of Pb-exposed specimens, females accumulated somewhat more Pb than males, making female chubs potentially more susceptible to possible toxic effects. CONCLUSIONS: The fact that Pb increase in gill and hepatic soluble fractions of the European chub was not caused by biotic factors and was spatially restricted to one site with increased dissolved Pb concentration in the river water points to the applicability of this parameter as early indicator of Pb exposure in monitoring of natural waters.
Show more [+] Less [-]Detection and quantitative analysis of 21 veterinary drugs in river water using high-pressure liquid chromatography coupled to tandem mass spectrometry Full text
2012
Dinky, | Nebot, Carolina | Miranda, Jose M. | Vázquez, Beatriz I. | Cepeda, Alberto
INTRODUCTION: The use of veterinary drugs in food production focuses on the control and improvement of animal health. The disadvantage of this practice is that pharmaceuticals and their metabolites are released into the environment, finding their way to natural water systems and becoming a potential risk to non-target organism. METHODS: This paper reports the development and validation of a quantitative method, based on high-performance liquid chromatography coupled to tandem mass spectrometry, for the simultaneous analysis of 21 veterinary drugs, antimicrobials, corticosteroids, coccidiostats and antifungal agents, in surface water. RESULTS: The precision of the method was established by calculating the mean recoveries, which were in the range of 94–101%. The developed method was employed to conduct the first monitoring study on the presence of veterinary drugs in the Galicia region, Northwest of Spain and was applied to 235 surface water samples. Eleven veterinary drugs were detected at concentrations from below the limit of quantification to 2,978.6 ng L−1. Limits of detection and quantification were in the range of 6.2 (betamethasone, cortisone, decoquinate, dexamethasone, maduramycin, monensin, narasin, salinomycin, sulfachloropyridazine, sulfamethoxypyridazine and trimethoprim) to 12.5 ng L−1 (for the rest of the selected drugs) and 12.5 (betamethasone, cortisone, decoquinate, dexamethasone, maduramycin, monensin, narasin, salinomycin, sulfachloropyridazine, sulfamethoxypyridazine and trimethoprim) to 25.0 ng L−1 (for the remaining pharmaceuticals), respectively. CONCLUSION: Sulfonamides were the group most frequently found, which are widely used in veterinary medicine.
Show more [+] Less [-]Performance evaluation of a tailor-made passive sampler for monitoring of tropospheric ozone Full text
2012
Özden, Özlem | Döğeroğlu, Tuncay
INTRODUCTION: This study presents the performance evaluation of a tailor-made passive sampler developed for the monitoring of tropospheric ozone. METHODS: The performance of the passive sampler was tested in the field conditions in terms of accuracy, precision, blank values, detection limit, effects of some parameters such as sampling site characteristics and sampling period on the field blanks, self-consistency, experimental and theoretical uptake rates, shelf life and comparison with commercial passive samplers. RESULTS: There was an agreement (R 2 = 0.84) between the responses of passive sampler and the continuous automatic analyser. The accuracy of the sampler, expressed as percent relative error, was obtained lower than 15%. Method precision in terms of coefficient of variance for three simultaneously applied passive samplers was 12%. Sampler detection limit was 2.42 μg m−3 for an exposure period of 1 week, and the sampler can be stored safely for a period of up to 8 weeks before exposure. Satisfactory self-consistency results showed that extended periods gave the same integrated response as a series of short-term samplers run side by side. The uptake rate of ozone was found to be 10.21 mL min−1 in a very good agreement with the theoretical uptake rate (10.32 mL min−1). The results of the comparison study conducted against a commercially available diffusion tube (Gradko diffusion tube) showed a good linear relationship (R 2 = 0.93) between two passive samplers. CONCLUSIONS: The sampler seems suitable to be used in large-scale measurements of ozone where no data are available or the number of existing automated monitors is not sufficient.
Show more [+] Less [-]Using a two site-reactive model for simulating one century changes of Zn and Pb concentration profiles in soils affected by metallurgical fallout Full text
2012
Mallmann, Fábio Joel Kochem | Rheinheimer, Danilo dos Santos | Labanowski, Jérôme | Cambier, Philippe | Lamy, Isabelle | Santanna, Maria Alice | Tessier, Daniel | Van Oort, Folkert
Using a two site-reactive model for simulating one century changes of Zn and Pb concentration profiles in soils affected by metallurgical fallout Full text
2012
Mallmann, Fábio Joel Kochem | Rheinheimer, Danilo dos Santos | Labanowski, Jérôme | Cambier, Philippe | Lamy, Isabelle | Santanna, Maria Alice | Tessier, Daniel | Van Oort, Folkert
Predicting the transfer of contaminants in soils is often hampered by lacking validation of mathematical models. Here, we applied Hydrus-2D software to three agricultural soils for simulating the 1900–2005 changes of zinc and lead concentration profiles derived from industrial atmospheric deposition, to validate the tested models with plausible assumptions on past metal inputs to reach the 2005 situation. The models were set with data from previous studies on the geochemical background, estimated temporal metal deposition, and the 2005 metal distributions. Different hypotheses of chemical reactions of metals with the soil solution were examined: 100% equilibrium or partial equilibrium, parameterized following kinetic chemical extractions. Finally, a two-site model with kinetic constant values adjusted at 1% of EDTA extraction parameters satisfactory predicted changes in metal concentration profiles for two arable soils. For a grassland soil however, this model showed limited applicability by ignoring the role of earthworm activity in metal incorporation.
Show more [+] Less [-]Using a two site-reactive model for simulating one century changes of Zn and Pb concentration profiles in soils affected by metallurgical fallout Full text
2012
Mallmann , Fábio Joel Kochem (Universidade Federal de Santa Maria, Santa Maria(Brésil). Departamento de Solos) | Rheinheimer , Danilo dos Santos (Universidade Federal de Santa Maria, Santa Maria(Brésil). Departamento de Solos) | Labanowski , Jérôme (Centre National de la Recherche Scientifique, Poitiers(France). UMR 6008, LCME, Université de Poitiers-ESIP) | Cambier , Philippe (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés) | Lamy , Isabelle (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés) | Santanna , Maria Alice (Universidade Federal de Santa Maria, Santa Maria(Brésil). Departamento de Física) | Tessier , Daniel (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés) | Van Oort , Folkert (INRA , Versailles (France). UR 0251 Physico-chimie et Ecotoxicologie des Sols d'agrosystèmes contaminés)
Predicting the transfer of contaminants in soils is often hampered by lacking validation of mathematical models. Here, we applied Hydrus-2D software to three agricultural soils for simulating the 1900–2005 changes of zinc and lead concentration profiles derived from industrial atmospheric deposition, to validate the tested models with plausible assumptions on past metal inputs to reach the 2005 situation. The models were set with data from previous studies on the geochemical background, estimated temporal metal deposition, and the 2005 metal distributions. Different hypotheses of chemical reactions of metals with the soil solution were examined: 100% equilibrium or partial equilibrium, parameterized following kinetic chemical extractions. Finally, a two-site model with kinetic constant values adjusted at 1% of EDTA extraction parameters satisfactory predicted changes in metal concentration profiles for two arable soils. For a grassland soil however, this model showed limited applicability by ignoring the role of earthworm activity in metal incorporation.
Show more [+] Less [-]Using a two site-reactive model for simulating one century changes of Zn and Pb concentration profiles in soils affected by metallurgical fallout Full text
2012
Kochem Mallmann, Fábio Joel | Rheinheimer dos Santos, Danilo | Cambier, Philippe | Labanowski, Jérôme | Lamy, Isabelle | Santanna, Maria Alice | Tessier, Daniel | van Oort, Folkert
Predicting the transfer of contaminants in soils is often hampered by lacking validation of mathematical models. Here, we applied Hydrus-2D software to three agricultural soils for simulating the 1900–2005 changes of zinc and lead concentration profiles derived from industrial atmospheric deposition, to validate the tested models with plausible assumptions on past metal inputs to reach the 2005 situation. The models were set with data from previous studies on the geochemical background, estimated temporal metal deposition, and the 2005 metal distributions. Different hypotheses of chemical reactions of metals with the soil solution were examined: 100% equilibrium or partial equilibrium, parameterized following kinetic chemical extractions. Finally, a two-site model with kinetic constant values adjusted at 1% of EDTA extraction parameters satisfactory predicted changes in metal concentration profiles for two arable soils. For a grassland soil however, this model showed limited applicability by ignoring the role of earthworm activity in metal incorporation.
Show more [+] Less [-]Mycoremediation—a prospective environmental friendly technique of bioseparation and dewatering of domestic wastewater sludge Full text
2012
Molla, Abul Hossain | Fakhru’l-Razi, Ahmadun
INTRODUCTION: Environmental safe and friendly management and disposal of wastewater sludge is a problem of every treatment plant throughout the world. Bioseparation and dewaterability of raw domestic wastewater sludge were evaluated for proper management and disposal by mycoremediation, i.e., using prior grown 2% (v/v) spore suspension of filamentous fungal (Mucor hiemalis Wehmer) broth inoculation, which were grown in 2% (w/v) solution of malt extract and wheat flour for 48–60 h in orbital shaker. DISCUSSION: Within 2–3 days of treatment application, encouraging results were achieved in total dry solids (TDS), total suspended solid (TSS), turbidity, chemical oxygen demand (COD), specific resistance to filtration (SRF), and pH due to fungal treatment in recognition of bioseparation and dewaterability of wastewater sludge compared to control. The significant reduction of TDS was remarked at fungal biomass (FB) in wheat flour (WF) treatment. The removal of TSS, turbidity, COD, and SRF were observed 96.0%, 99.4%, 92.6%, and 97.6%, respectively, in supernatant at 5 days by FB in WF. The SRF measuring the dewaterability was decreased with maximum (0.26 × 10−12 mg/kg) equivalent to 95.5% at 2 days in FB in WF also. FB in WF broth is a potential, environmental friendly, comparatively low-cost biological technique which might play the significant role for bioremediation and bioseparation of domestic wastewater sludge. The present technique may bring a dynamic change in treatment of wastewater in future.
Show more [+] Less [-]Personal monitoring of exposure to particulate matter with a high temporal resolution Full text
2012
Broich, Anna V. | Gerharz, Lydia E. | Klemm, Otto
BACKGROUND: Continuous monitoring of air quality is implemented by government institutions at fixed ambient sites. However, the correlation between fixed site measurements and exposure of individual persons to air contaminants is likely to be weak. MATERIALS AND METHODS: We measured particulate matter both outdoors and indoors by following the spatial movement of individuals. Sixteen test persons took part and carried a measurement backpack for a 24-h period. The backpack was comprised of a Grimm Aerosol Spectrometer model 1.109, a GPS device, and a video camera for tracking of human behavior. The spectrometer provided information about particle numbers and mass in 32-size classes with a high temporal resolution of 6 s. RESULTS: The personal exposure of individuals during 24 h could significantly exceed the outdoor particulate matter (PM)₁₀ concentrations measured at the fixed sites. The average 24-h exposure of all test persons for PM₁₀ varied from 27 to 322 μg m⁻³. Environmental tobacco smoke and cooking emissions were among the main indoor sources for PM. The amount of particulate matter a test person was exposed to was highly dependent on the spatial behavior and the surrounding microenvironment conditions. DISCUSSION: Large-scale experiments including personal measurements might help to improve modeling approaches to approximate the actual exposure on a statistically sound basis.
Show more [+] Less [-]Organochlorine pesticides and polychlorinated biphenyls in air and soil across Azerbaijan Full text
2012
Aliyeva, Gulchohra | Kurkova, Romana | Hovorkova, Ivana | Klánová, Jana | Halsall, Crispin
Concentrations of selected organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) are reported in air and surface soil in an extensive spatial survey across Azerbaijan, a country bordering the Caspian Sea with a history of OCP production and extensive use. Polyurethane foam disc passive air samplers (PAS) were deployed during October–November 2008 with soil samples collected in July 2009. Levels of Σ7PCB in ambient air were generally low (mean of 0.046 ng m−3, n = 13) and comparable to concentrations reported in countries within Eastern Europe and similar to or lower than concentrations reported in urban air in the UK and other western countries. Surprisingly, PCB concentrations in rural/background soil fell below the method detection limits at most sites, although concentrations were 0.209 and 0.071 ng Σ7PCB g−1 dry weight (dw) for two urban sites, again comparable to PCB levels measured at background sites in Europe. Levels of α-HCH, β-HCH, γ-HCH and p,p′-DDT/E were elevated in ambient air across Azerbaijan in comparison to PAS-derived concentrations reported elsewhere, with concentrations of α-HCH in air ranging from 0.085 to 2.699 ng m−3 and p,p′-DDE, 0.037–2.290 ng m−3. High concentrations of OCPs occurred at several of the urban sites and at sites in proximity to old pesticide storage facilities with concentrations in soil >0.1 μg g−1 dw for p,p′-DDE and p,p′-DDT at several sites. The ratio of p,p′-DDT/p,p′-DDE was close to unity in the soil at these sites, but elsewhere, the ratio was <1, indicating a weathered DDT pattern, which was also reflected in the air at all sites. A fugacity approach revealed the strong likelihood of net soil-to-air transfer at the majority of sites for all OCPs. The calculated annual fluxes or loading to the atmosphere from a rural/agricultural area (representing land as vineyards and cotton cultivation) were estimated to be on the order of ≈10–100 kg year−1 for the HCH isomers (including the β -isomer) and p,p′-DDE. The high levels of OCPs in soils, particularly in the vicinity of obsolete-pesticide storage facilities and at select urban sites are of concern and warrant regular monitoring activities and the development of containment or mitigation strategies.
Show more [+] Less [-]Comparison of methods for evaluation of activity of photocatalytic films Full text
2012
Simonsen, Morten E. | Sørensen, Martin B. | Søgaard, Erik G.
OBJECTIVE: This work aims to investigate the correlation between the photocatalytic activity determined by methylene blue bleaching (DIN 52980), stearic acid degradation, and degradation of acetone in gas phase. METHOD: The photocatalytic TiO2 coatings included in this investigation ranged from thin commercially available coatings (ActivTM and BioCleanTM) and ready to use suspensions (Nano-X PK1245) to lab-produced PVD and sol–gel coatings. XRD analysis of the photocatalytic coatings showed that all the coatings consisted of nanocrystalline anatase, although the thickness and porosity varied considerably. RESULTS: The study showed that the reproducibility of the activity measurements was good. However, more importantly, the investigation showed that there is a good correlation between the activities determined by the different methods even though the characteristics of the photocatalytic coatings and the organic probe molecules varied considerably. CONCLUSION: The overall findings of this work suggest that there is a good correlation between the investigated methods. These results are promising for the future work concerning standardization of methods for determination of the activity of photocatalytic films.
Show more [+] Less [-]Microbial structure and chemical components of aerosols caused by rotating brushes in a wastewater treatment plant Full text
2012
Han, Yunping | Li, Lin | Liu, Junxin | Zhang, Mengzhu
PURPOSE: Bacterial community structure and the chemical components in aerosols caused by rotating brushes in an Orbal oxidation ditch were assessed in a Beijing municipal wastewater treatment plant. METHODS: Air samples were collected at different distances from the aerosol-generating rotating brushes. Molecular culture-independent methods were used to characterize the community structure of the airborne bacteria in each sample regardless of cell culturability. A clone library of 16S rDNA directly amplified from air DNA of each sample was constructed and sequenced to analyze the community composition and diversity. Insoluble particles and water-soluble ions emitted with microorganisms in aerosols were analysis by a scanning electron microscope together with energy dispersive X-ray spectroscopy and ion chromatogram analyzer. RESULTS: In total, most of the identified bacteria were Proteobacteria. The majority of sequences near the rotating brushes (the main source of the bioaerosols) were Proteobacteria (62.97 %) with β-(18.52 %) and γ-(44.45 %) subgroups and Bacteroidetes (29.63 %). Complex patterns were observed for each sampling location, suggesting a highly diverse community structure, comparable to that found in water in the Orbal oxidation ditch. Accompany with microorganisms, 46.36 μg/m3 of SO 4 2− , 29.35 μg/m3 of Cl−, 21.51 μg/m3 of NO 3 − , 19.76 μg/m3 of NH 4 + , 11.42 μg/m3 of PO 4 3− , 6.18 μg/m3 of NO 2 − , and elements of Mg, Cl, K, Na, Fe, S, and P were detected from the air near the aerosols source. CONCLUSIONS: Differences in the structure of the bacterial communities and chemical components in the aerosols observed between sampling sites indicated important site-related variability. The composition of microorganisms in water was one of the most important sources of bacterial communities in bioaerosols. Chemical components in bioaerosols may provide a media for airborne microorganism attachment, as well as a suitable microenvironment for their growth and survival in the air. This study will be benefit for the formulation of pollution standards, especially for aerosols, that take into account plant workers’ health.
Show more [+] Less [-]Molecular cloning and expression of novel metallothionein (MT) gene in the polychaete Perinereis nuntia exposed to metals Full text
2012
Won, Eun-Ji | Rhee, Jae-Sung | Ra, Kongtae | Kim, Kyung-Tae | Au, Doris W. T. | Shin, Kyung-Hoon | Lee, Jae-seong
To report a novel metallothionein (MT) gene and evaluate its potency as a biomarker, we clone this MT gene and measured the expression levels in the metal-exposed polychaete Perinereis nuntia. Accumulated metal contents and metallothionein-like proteins (MTLPs), which have been recognized as potential biomarkers, were compared with the relative mRNA expressions of the MT gene of P. nuntia (Pn-MT). In addition, the metal-binding affinity was estimated by recombinant Pn-MT protein. Pn-MT having high cysteine residues with three metal response elements in the promoter region closely clusters with those of other invertebrates. The accumulation patterns of metals were dependent on the exposure times in lead (Pb), cadmium (Cd), and copper (Cu) exposure. Particularly, both MTLP levels and relative mRNA expressions of MT were increased with accumulated metal contents and exposure time in P. nuntia exposed to Pb and Cd. There was no significant modulation of the Pn-MT gene in polychaetes exposed to Zn and As. However, the metal-binding ability of the recombinant Pn-MT protein provides a clear evidence for a high affinity of MT to several metal elements. These results suggest that Pn-MT would play an important role in the detoxification and/or sequestration of specific metals (e.g., Pb and Cd) in P. nuntia and have potential as a molecular biomarker in the monitoring of the marine environment using a polychaete.
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