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101.
Background, Aim and Scope
Part 1: Behaviour of Polycyclic Musks in Sewage Sludge of Different Treatment Plants in Summer and Winter
Part 2: Investigation of Polycyclic Musks in Soils and Plants
- Preamble. In Part 1 of the study, screening tests were performed to investigate the occurrence of PCMs in sewage sludges.
For a preliminary risk assessment, further information is needed about their behaviour in the terrestrial environment. Hence,
Part 2 examined the adsorption of PCMs to soil, their dissipation and leaching in soil and their uptake by plants.
Background, Aim and Scope Polycyclic Musks (PCMs) enter the environment via the waste water system. Because of their persistence, they can accumulate
in different matrices like sewage sludge or biota. By the use of sewage sludge as a fertilizer, PCMs are transferred to agricultural
soils. Therefore, in Part 1 of the study, screening tests were performed to investigate the occurrence of PCMs in sewage sludge.
For a preliminary risk assessment, further information is needed about their behaviour in the terrestrial environment. Hence,
Part 2 of the study examined the adsorption of PCMs to soil, their dissipation and leaching in soil, and their uptake by plants.
Materials and Methods:
In the screening study, samples of activated sewage sludge were taken both in summer and in winter at 21 treatment plants.
In order to get an overview of the contamination situation, sampling covered different types of treatment plants (in rural,
urban, industrial areas). Analytical methods for the determination of HHCB, AHTN, ADBI, ATTN, AHDI and ATII in the sludge
samples were developed and applied.
Results:
The analytical screening of PCMs showed their presence in activated and dried sewage sludge samples. HHCB and AHTN represented
about 95% of the PCMs investigated. Their concentrations in the activated sludge samples varied between 2.9 and 10.4 mg/kg
dry mass (dm) and 1.1 to 4.2 mg/kg dm, respectively. Although different types of sewage treatment plants were investigated,
similar PCM levels were found, showing the widespread input of these compounds into domestic waste water.
Discussion:
PCM concentrations in activated sludge varied widely. The variation drops substantially when concentrations are related to
the varying dry mass. In dehydrated sludge, PCM concentrations were up to 24 mg/kg dm for HHCB and up to 6.9 mg/kg dm for
AHTN. These high values are comparable to those obtained in other investigations analysing PCMs. If the degradation of organic
mass during anaerobic decomposition is included in the evaluation, the figures obtained are comparable to those for activated
sludge. Elimination in sewage sludge was higher in summer than in winter. Therefore, the contamination of the sludges in winter
reached higher levels compared to the summer.
Conclusions:
The results show that PCMs are widespread contaminants in sewage sludge.
Recommendations and Perspectives:
PCM should be considered in a risk assessment as potential contaminants of sewage sludge destined for agricultural use.
Due to the high PCM levels in sewage sludge, further investigations into the degradation and elimination behaviour in sewage
sludge have to be carried out, including that involving PCM metabolites such as lactone derivatives. 相似文献
102.
Prange A Modrow H Hormes J Krämer J Köhler P 《Journal of agricultural and food chemistry》2005,53(17):6930-6938
Cereals contaminated by Aspergillus spp., Penicillium spp., and Fusarium spp. and their mycotoxins, for example, ochratoxin A (OTA) and deoxynivalenol (DON), are not only a risk to human and animal health but can also show poor technological properties and baking quality. The influence of these genera on the sulfur speciation of low molecular weight (LMW) subunits of glutenin was characterized by investigating suboptimally stored wheat samples in situ by X-ray absorption near edge structure (XANES) spectroscopy and baking tests. Field fungi of the genus Fusarium have hardly any influence on both the sulfur speciation of wheat gluten proteins and the baking properties, whereas storage fungi of the genera Aspergillus and Penicillium have a direct influence. An increased amount of sulfur in sulfonic acid state was found, which is not available for thiol/disulfide exchange reactions in the gluten network, and thus leads to a considerably reduced baking volume. From changes of the composition of the mould flora during suboptimal storage of wheat and from the mycotoxin contents, it can be concluded that microbial competitive interactions play an important role in the development of the mould flora and the mycotoxin concentrations during (suboptimal) storage of wheat. 相似文献
103.
Möller H Grelier S Pardon P Coma V 《Journal of agricultural and food chemistry》2004,52(21):6585-6591
To prepare composite films from biopolymers with anti-listerial activity and moisture barrier properties, the antimicrobial efficiency of chitosan-hydroxy propyl methyl cellulose (HPMC) films, chitosan-HPMC films associated with lipid, and chitosan-HPMC films chemically modified by cross-linking were evaluated. In addition, the physicochemical properties of composite films were evaluated to determine their potential for food applications. The incorporation of stearic acid into the composite chitosan-HPMC film formulation decreased water sensitivity such as initial solubility in water and water drop angle. Thus, cross-linking of composite chitosan-HPMC, using citric acid as the cross-linking agent, led to a 40% reduction in solubility in water. The water vapor transfer rate of HPMC film, approximately 270 g x m(-2) x day(-1) x atm(-1), was improved by incorporating chitosan and was further reduced 40% by the addition of stearic acid and/or cross-linking. Anti-listerial activity of films was determined on solid medium by a numeration technique. Chitosan-HPMC-based films, with and without stearic acid, inhibited the growth of Listeria monocytogenes completely. On the other hand, a loss of antimicrobial activity after chemical cross-linking modification was observed. FTIR and 13C NMR analyses were then conducted in order to study a potential chemical modification of biopolymers such as a chemical reaction with the amino group of chitosan. To complete the study, the mechanical properties of composite films were determined from tensile strength assays. 相似文献
104.
105.
Johansson L Rytkonen A Bergman P Albiger B Källström H Hökfelt T Agerberth B Cattaneo R Jonsson AB 《Science (New York, N.Y.)》2003,301(5631):373-375
The human-specific bacterial pathogen Neisseria meningitidis is a major cause of sepsis and/or meningitis. The pili of N. meningitidis interact with CD46, a human cell-surface protein involved in regulation of complement activation. Transgenic mice expressing human CD46 were susceptible to meningococcal disease, because bacteria crossed the blood-brain barrier in these mice. Development of disease was more efficient with piliated bacteria after intranasal, but not intraperitoneal, challenge of CD46 transgenic mice, suggesting that human CD46 facilitates pilus-dependent interactions at the epithelial mucosa. Hence, the human CD46 transgenic mice model is a potentially useful tool for studying pathogenesis and for vaccine development against meningococcal disease. 相似文献
106.
Sabine Augustin Jan Evers Hans-Peter Dietrich Johannes Eichhorn Thomas Haussmann Regina Icke Ansgar Isenberg Wolfgang Lux Monica Musio Hans Pretzsch Winfried Riek Thomas Rötzer Bernd Schultze Andreas Schulze Jörg Schröder Walter Seidling Nicole Wellbrock Klaus von Wilpert Barbara Wolff 《European Journal of Forest Research》2005,124(4):251-260
In the 1970s unexpected forest damages, called “new type of forest damage” or “forest decline”, were observed in Germany and
other European countries. The Federal Republic of Germany and the German Federal States implemented a forest monitoring system
in the early 1980s, in order to monitor and assess the forest condition. Due to the growing public awareness of possible adverse
effects of air pollution on forests, in 1985 the ICP Forests was launched under the convention on long-range transboundary
air pollution (CLRTAP) of the United Nations Economic Commission for Europe (UN-ECE). The German experience in forest monitoring
was a base for the implementation of the European monitoring system. In 2001 the interdisciplinary case study “concept and
feasibility study for the integrated evaluation of environmental monitoring data in forests”, funded by the German Federal
Ministry of Education and Research, concentrated on in-depths evaluations of the German data of forest monitoring. The objectives
of the study were: (a) a reliable assessment of the vitality and functioning of forest ecosystems, (b) the identification
and quantification of factors influencing forest vitality, and (c) the clarification of cause-effect-relationships leading
to leaf/needle loss. For these purposes additional data from external sources were acquired: climate and deposition, for selected
level I plots tree growth data, as well as data on groundwater quality. The results show that in particular time series analysis
(crown condition, tree growth, and tree ring analysis), in combination with climate and deposition are valuable and informative,
as well as integrated evaluation of soil, tree nutrition and crown condition data. Methods to combine information from the
extensive and the intensive monitoring, and to transfer process information to the large scale should be elaborated in future.
相似文献
Sabine AugustinEmail: |
107.
Hellal F Hurtado A Ruschel J Flynn KC Laskowski CJ Umlauf M Kapitein LC Strikis D Lemmon V Bixby J Hoogenraad CC Bradke F 《Science (New York, N.Y.)》2011,331(6019):928-931
Hypertrophic scarring and poor intrinsic axon growth capacity constitute major obstacles for spinal cord repair. These processes are tightly regulated by microtubule dynamics. Here, moderate microtubule stabilization decreased scar formation after spinal cord injury in rodents through various cellular mechanisms, including dampening of transforming growth factor-β signaling. It prevented accumulation of chondroitin sulfate proteoglycans and rendered the lesion site permissive for axon regeneration of growth-competent sensory neurons. Microtubule stabilization also promoted growth of central nervous system axons of the Raphe-spinal tract and led to functional improvement. Thus, microtubule stabilization reduces fibrotic scarring and enhances the capacity of axons to grow. 相似文献
108.
Massimiliano Cardinale Valerio Bartolino Marcos Llope Luigi Maiorano Mattias Sköld Jacob Hagberg 《Fish and Fisheries》2011,12(3):289-298
Increased knowledge on the spatial distribution of marine resources is crucial for the implementation of a true ecosystem approach to management and the conservation of marine organisms. For exploited fish species characterized by aggregation behaviour during spawning time, the identification and tracking of spawning areas is essential for a correct assessment of their productivity and population abundance. To elucidate this concept, we reconstructed the spatio‐temporal distribution of adult plaice (Pleuronectes platessa, Pleuronectidae) during spawning time along the 20th century. Historical data reveal that not only the abundance but also the former population richness was much higher than previously estimated and has declined because of protracted over‐exploitation during the last 30 years. We conclude that forecast of stock recovery to former levels of abundance neglecting spatial reorganizations might be over‐optimistic and shaded by a lost memory of the past population richness. These results reinforce the importance of managing exploited marine resources at a greater spatial resolution than has been carried out in the history of fishery management. 相似文献
109.
C. Börner 《Journal of pest science》1932,8(4):38-40
Ohne Zusammenfassung
„Mitteilungen über Blattl?use” 1–8, s. diese Zeitschrift 1931, S. 8–11; 9–11 S. 28–30; 12–13 S. 42–43; 14 S 117; 15–16 S.
128–130; 17–20, 1932, S. 32–33. 相似文献
110.
Carl Börner 《Journal of pest science》1932,8(5):52-54
Ohne Zusammenfassung 相似文献