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1.
Drugs are emitted into the environment by hospitals, private households, veterinary and human practices. Remnants of these products are primarily disposed of in landfill sites. At the present, there is no information available about the behaviour of pharmaceutical drugs, like their anaerobic biodegradation or adsorption, in sanitary landfills. Some of these drugs, e.g. antineoplastic substances such as ifosfamide, are supposed to be cancerogenic, mutagenic, fetotoxic or embryotoxic. Therefore, we investigated the behaviour of ifosfamide during waste decomposition in a laboratory-scale lysimeter. Up to 50% of the ifosfamide was eliminated under methanogenic conditions; but the mechanism applying for the elimination remains unclear. As far as present day knowledge is concerned, the risk for the environment through the emission of emitting ifosfamide from sanitary landfills should be negligible.  相似文献   

2.

Goal and Scope

The information value of microbiologicalecotoxicological investigations of pesticides in soil increases if reference compounds with known biocidal effects are included. But those reference compounds used until now often are of remarkable environmental and human toxicity and therefore are difficult to handle. Inorganic neutral salts sometimes were discussed as alternatives, but their suitability needs to be tested before.

Methods

For laboratory experiments some microbial activities in soil were selected whose effects had been proved in several microbiological-ecotoxicological investigations. They include the mineralization of carbon and nitrogen (+ nitrification) as well as the biomass-related parameters dehydrogenase activity and substrate-induced short-term respiration. Several agricultural soils were used to confirm the results.  相似文献   

3.
Background, aim, and scope Determination of the rates of microbial alkylation are of interest with respect to natural attenuation of harmful selenium concentrations or selenium charges in contaminated ecosystems. Materials and methods Landfill gas and the headspace of microbial microcosm incubation vessels were sampled in Tedlar® bags. On-line hyphenation of an efficient enrichment method (cryotrapping-cryofocusing), a gaschromatographic separation technique, and the sensitive ICP-MS detection system was used for speciation of volatile organoselenium compounds. A detection limit at the ultra trace level (pg Se) was achieved with this CT-CF-GC-ICP-MS technique. Results Incubation of landfill leachate with Alternata alternata as an active methylating organism showed a production of volatile selenium compounds (DMSe, DMDSe, EMDSe, DEDSe) over the whole range of applied inorganic selenium concentrations (10?µg?L–1 to 10?mg?L–1), with volatilization rates of up to 10?mg m–3?d–1. For selenium concentrations of 1?mg?L–1 in the nutrient broth, up to 7?% of the inorganic selenium was volatilized after one week. The same volatile selenium compounds were observed in landfill gas. Discussion The amount of volatilized selenium was comparable to that found in other studies with microbial pure cultures as well as isolates from waters or soils, but at much lower initial concentrations used in the incubations. Conclusions The alkylation of selenium in the enriched mixed culture from landfill leachate at environmentally relevant concentrations indicates that the organoselenium compounds of same species composition and distribution determined in landfill gas are produced by microorganisms. Recommendations and perspectives The microbial alkylation of toxic inorganic selenium species to less toxic or non-toxic, volatile compounds is an efficient method for bioremediation of contaminated sites even at relatively low Se concentrations.  相似文献   

4.
This study is based on the theses that
  1. early diagnosis is indispensable in the context of precautionary policy for the management of environmental problems which have the character of a “creeping disaster” and that
  2. the public must play the active role that is adequate within a democratic society. In the context of the study, three existing advisory committees for environmental policy as well as two concepts which have not been put into effect are investigated.
In the fourth part the work of the oldest of the committees, the SRU, is examined with respect to the three most important environmental problems of the last 15 years. In part I, the concept of the Picht commission from 1972, which has never been realized in this form, was introduced. In part II, the concepts and the working method of the three existing advisory committees (SRU, WBGU, TAB) were presented. Part III deals with the critique of these committees and an alternative concept of early diagnosis which has not yet been put into effect.  相似文献   

5.
This study is based on the theses that
  1. early diagnosis is indispensable for the management of environmental problems in the context of precautionary policy, which have the character of a “creeping disaster” and that
  2. the public must play the active role that is adequate within a democratic society.
In the context of the study, three existing advisory committees for environmental policy as well as two concepts which have not been put into effect are investigated. In the second part of the study the concepts and the working method of the three existing advisory committees are portrayed: the Council of Experts for Environmental Questions (SRU), the German Advisory Council on Global Change (WBGU), and the Office of Technology Assessment of the Federal Parliament (TAB). In part I, the concept of the Picht commission from 1972, which has never been implemented in this form was introduced. Part III deals with the critique of these committees and with an alternative concept of early diagnosis which has not yet been put into effect. In part IV, the work of the oldest of the committees, the SRU, is examined with respect to the three most important environmental problems of the last 15 years.  相似文献   

6.
This study is based on the theses that
  1. early diagnosis is indispensable in the context of precautionary policy for the management of environmental problems, which have the character of a “creeping disaster”; and that
  2. the public must play the active role that is adequate within a democratic society. In the context of the study, three existing advisory committees for environmental policy as well as two concepts which have not been put into effect are investigated.
In the first part presented here, the concept of the Picht commission from 1972, which has never been realized in this form is introduced. In part II, the concepts and the working method of the three existing advisory committees (SRU, WBGU, TAB) are presented. Part III deals with the critique of these committees and an alternative concept of early diagnosis which has not yet been put into effect. In part IV, the work of the oldest of the committees, the SRU, is examined with respect to the three most important environmental problems of the last 15 years.  相似文献   

7.
This study is based on the theses that
  1. early diagnosis is indispensable in the context of precautionary policy for the management of environmental problems which have the character of a “creeping disaster”, and that
  2. the public must play the active role that is adequate within a democratic society.
In the context of the study, three existing advisory committees for environmental policy as well as two concepts which have not been put into effect are investigated. The third part deals with the critique of these committees and an alternative concept of early diagnosis “General Ecological Monitoring” which has not yet been put into effect. In part I, the concept of the Picht commission from 1972, which has never been realized in this form has been introduced. In part II, the concepts and the working method of the three existing advisory committees (SRU, WBGU, TAB) have been presented. In part IV, the work of the oldest of the committees, the SRU, is examined with respect to the three most important environmental problems of the last 15 years.  相似文献   

8.
To include consequences emanating from former military sites on the drinking water supply, a catalog of criteria has been developed which permits the determination and assessment of the hazards in general and their impact on human health in particular. The assessment criteria correspond to the special requirements and standards for drinking water hygiene and protection in Germany. The criterion catalog is a completion module to the usual praxis and existing conceptions, and has proved its practical value in the initial assessment of military sites in the new federal states of Germany. The scheme is a control instrument suitable for obtaining an assessment concerning the extent to which drinking-water resources are and will be affected by former waste disposal and other contaminated sites at the present and in the future.  相似文献   

9.
Background, aim, and scope In the district List of Hanover (Lower Saxony) radioactive contaminations of the ground were detected at a site of a former chemical plant. Due to the lack of an ordinance regarding intervention regulations in the case of radioactive contaminations in Germany this situation had to be assessed on the basis of scales and methods of the German regulations concerning soil protection and contaminated sites. In particular it was necessary to develop methods and levels for the assessment of radioactive contaminations. Materials and methods Because radioactivity can be considered as a carcinogenic substance the methodical approaches of the BBodSchV for this group of substances were used in order to derive test thresholds for radioactive contaminations at children’s play areas, residential areas as well as parks and recreation facilities. Results For the assessment of radioactive soil contaminations with naturally occurring radionuclides at children’s play areas and residential areas the ingestion of soil is the decisive pathway of exposure. For children’s play areas a threshold level of 0.2?Bq/g for the sum U-238,max?+?Th-232,max was obtained. At areas with only impacts of ambient radiation from the contaminated ground test thresholds of 0.5?µSv/h are recommended. A special pathway is the migration of radon from the contaminated soil into basement floors of buildings. Taking into account the natural background levels of radon a concentration of 260?Bq/m³ is suggested as a test threshold in the framework of soil protection benchmarks. Discussion and conclusions will be described in Part 2 of the paper.  相似文献   

10.
Background, aim, and scope In Part 1 of this paper test thresholds for radionuclides in soil have been derived on the basis of methods and scales of the German Ordinance on Soil Protection (BBodSchV). In this paper, these test thresholds are checked with regard to their plausibility. Materials, methods, results are described in Part 1 of this paper. Discussion This contribution demonstrates that the test thresholds derived in Part 1 are plausible and feasible according to the requirements of the established methods. The epidemiological basis for the treatment of ionizing radiation is well founded. Risks can be quantified via the knowledge of cancer risks due to radiation. As a reference value the overall fatal risk coefficient of 5?% per Sv recommended by ICRP is used. The test thresholds obtained are sufficiently far from background levels in soils of northern Germany. Consequently, the test thresholds are applicable without any background corrections. Exposures by external radiation outdoors and exposures by inhalation of radon in cellar rooms result in calculated test thresholds in the order of background levels. Nevertheless, feasible results are obtained because in the case of toxic substances without threshold levels the additional exposures are considered for determination of test thresholds. Conclusions The approach of test thresholds for radioactive soil contamination presented in Part 1 of this paper complies with the criteria of the German methods for calculation of test thresholds in soil protection regarding plausibility and feasibility. It enables the soil protection authorities to assess radioactive contaminations of the ground according to the established rules in the field of soil protection and to make decisions according to Articles 9 and 10 of the German Soil Protection Act. Part 3 of this paper discusses the application of the test thresholds and the possibilities of determining the need for remediation actions.  相似文献   

11.
Waste recycling is provided by law, e.g. the German ‘Kreislaufwirtschafts- und Abfallgesetz’. Even street sweepings can be recycled, e.g. as winter grit. But if street sweepings are repeatedly brought back on street, toxic agents as heavy metals can accumulate. What is the amount of heavy metal load? Regarding this, is it possible to recycle street sweepings? Is it possible to reduce heavy metal load with the smallest size fraction (the highest load being assumed in) is treated as disposal? Are these fractions actually highest loaded? These questions have been the framework of two studies elaborated at Schleswig-Holstein’s State Authority of Nature Protection and Environment (LANU) based on samples from cities in German state Schleswig-Holstein, particularly from its capital city Kiel. Threshold values for that very purpose do not exist in Germany. But a working group of all German states (called LAGA) suggested some approximate values for recycling of waste and other remainder0materials; the values have been fixed in state of law in Schleswig-Holstein. Our evaluation is oriented towards them. The samples taken in autumn 1998 and winter 1999 were devided in three fractions, the amount of heavy metal measured for each fraction with an ICP-AES. Normal disintegration for that purpose is aqua regia. In this case study nitric acid had been used dissolving just a part of heavy metal concentration although it is not a standard method. It is assumed that it better simulates the natural solubility, and additionally, it is less costly. Therefore we insistently recommend to discuss the application of this method. Samples taken in autumn were higher loaded than those taken in winter. It is worth of special remark that there are high values for zinc, copper, and lead in autumn samples. Regarding above mentioned approximate values samples taken in winter can be assessed for recycling, whereas samples taken in autumn were loaded too high. The finest fraction (<0.5 mm) of samples taken in winter were highest loaded as expected. Therefore the heavy metal concentration could be reduced if this fraction would be treated as disposal. The same can not be assumed for samples taken in autumn, probably due to the higher amount of organic matter.  相似文献   

12.
Since the increasing awareness of environmental damage, attention has focussed on the problems caused by the extension of car traffic. The number of cars has permanently increased over the years and is predicted to continue in the future. The number of cars registered worldwide already passed the number of 500 million in the year 1988 (OECD, 1995). Two major problems are linked to the increase in car traffic: The air pollution by engine conbustion and the so-called sealing of the ground by pavements. The streets dramatically cut into coherent areas, separate biotopes, animal and plant populations (BBR, 1998). Facts about grund sealing in Germany are presented and compared to those of other OECD-countries. Environmental consequences are discussed.  相似文献   

13.
Estimations of consumer exposure by inhalation have been calculated taking point estimates and were compared to estimates from a probabilistic approach using Monte Carlo analysis. The calculation is based on a model in which the liberation of the highly volatile substance, xylene is only limited by the velocity of administration. The loss of the substance is limited by the air exchange rate. It is also assumed that the substance is used in a single room. Other compartments were not considered. The distribution of xylene in solvent based paints was evaluated by probability analysis of the BgVV product data base. In the products there were xylene concentrations in a range between ~1 and 44% with a median concentration of 11,2%. For “normal-case” assumptions the exposure estimate differed between single-point and probabilistic calculations: The peak concentration in a room was 0,99 g/m3 taking the single-point and 0,49 g/m3 taking the distribution. The average concentration during duration of use was 0,16 g/m3 and 0,083 g/m3, respectively. Interestingly, comparison with calculations taking the EPA-SCIES programme revealed similar concentrations showing that models are comparable.  相似文献   

14.
The Water Framework Directive’s (WFD) choice of good ecological status as a metric of the immission situation in water bodies implicitly considers the exposure of biota to pollutants. However, the exposure concept lacks consequent links to food webs and substance cycles where sediments and suspended matter play an important role. This is traceable in monitoring as well as in evaluation schemes. This article identifies the major challenges towards a process-oriented approach.  相似文献   

15.
For the application of sequential extraction of heavy metals from samples that can only be obtained in amounts of a few milligrams (micro samples, e.g. airborne dust fallout), the method afterZeien &Brümmer (1989) was progressed. A down scale to 1∶100 was carried out and the accuracy of this method with variable sample amounts of about 20 mg and an extraction volume of 500 μl was proofed with standard soil samples. The influence of variable extraction ratios (ratio of sample amount and volume of extraction solvent) and the influence of intensive treatment of dust sampled by the Bergerhoff-method (VDI 2119/2, 1972) prior sequential extraction, was within the precision of measurement of our method. Thus, we showed that sequential extraction can be applied for the investigation of heavy metal mobilization in micro samples with variable sample amounts. A first application of our method for microsamples was carried out to investigate airborne dust fallout and street sediments at two urban sites where different heavy metal immission rates due to traffic influence occur. These investigations will be presented in part 2 (“Sequential extraction of heavy metals from urban dust”).  相似文献   

16.
Loads of Pb, Cd, Ni, Cu and Zn in litter from trees of representative roads in Kiel are analyzed by means of atom-absorption spectroscopy (Chapter 1). The heavy metal loads are far beyond relevant quality measures (Chapter 2). Consequently, the litter-compost could be used for horticulture and need not be stored, for instance, at waste deposits. No statistically significant correlations exists between the litter’s heavy metal loads and boundary conditions such as density of traffic, spatial structure of allocation of buldings, micro-climatic situation, tree species or allocation of streets within Kiel.  相似文献   

17.
The Federal Institute of Hydrology has developed operating strategies in order to deal with dredged material within the scope of the Waterways and Shipping Administration. Sediments will be assessed based on certain quality parameters. The potential environmental impact at the source and relocation areas has to be evaluated in respect to ecological and economical issues. A coordinated sediment management plan for the Rhine River was commissioned. The most important contaminated sedimentation areas were identified, and special sedimentation areas were classified based on ecological impact or even risk. Proposals for economical and ecological strategies are discussed. Further developments for operational instructions dealing with sediments and dredged material in federal waterways are still being processed. The objectives of the river basin commissions as well as those of the stakeholders have to be met in an appropriate manner. In the framework of the analysis and impact of climate change on both sediment quantity and quality for optimizing sediment management, one or more dimensional hydraulic models will be applied. This will help gain a better insight into the understanding of contaminant transport in freshwater bodies.  相似文献   

18.

Objectives

The second Gulf War (1991) led to the largest oil spill in human history. Over 770 km of coastline from southern Kuwait to Abu Ali Island (Saudi Arabia) were smothered with oil and tar, erasing most of the local plant and animal communities. This long term study was designed to reveal the processes of natural regeneration within the salt marsh ecosystems as well as the processes counter productive to regeneration.

Methods

Field data were collected along permanent transect lines during annual visits from 1994 to 2004. Soil analysis included grain size, carbonate, pH and total hydrocarbon (Soxhlet extraction). Heavy metals were determined by Inductively Coupled Plasma Atomic Emission Spectroscopy. Hydrocarbons were analysed by High Performance Liquid Chromatography.

Results

The dominant processes of regeneration are characterized by four types of indicators. These are 1) the composition of hydrocarbon compounds remaining in the soil, 2) the hardness of the soil surface, 3) the abundance of laminated cyanobacterial mats, and 4) the abundance and diversity of macrofauna. Cyanobacteria turned out to conserve the oil within the soil where they built laminated mats sealing the surface and thus, preventing oxygen from penetrating the substrate. On the other hand, crustaceans were the first macrofauna returning to contaminated soils. Following bioturbation by the crustaceans significantly accelerates the biodegradation of the hydrocarbons. Since the occurrence of the crabs (mainly Cleistostoma dotilliforme) is primarily restricted to tidal channels the density of the channel network between the affected salt marshes determines the time which is needed for regeneration.

Conclusions

The re-setrlement of crabs is the key process initiating fast and effective biodegradation of the oil residues in the intertidal soils. Because dense laminated cyanobacterial mats and tar covered surface substrates often delay the re-settlement of crabs — even 13 years after the impact — tidal channels are the initial paths of re-colonisation.

Recommendations and Perspectives

Therefore it is recommended that if any restoration measures are to be undertaken, it would be most effective to create a network of artificial channels within the salt marshes in order to bring the pioneer species into the most affected ecosystems.  相似文献   

19.

Background

Methane as a gas influencing our climate is of high importance according to the Kyoto-Protocol. The more precisely we can determine anthropogenic and biogenic sources, the more effective measures we can take to reduce the gas. Direct emission of methane from plants apparently contributes significantly to the total emission but has not been accounted for in emission balances until now.

Methods

A model was created to calculate methane emission for a short time period in regional resolution for Lower Austria and to relate the results to known literature.

Results and Discussion

First model results suggest that the amount of methane released from plants in relation to emissions from other known sources are of importance.

Perspectives

The uncertainties associated with both measurements and quantification require reduction by further research.  相似文献   

20.
Until now, assessment of contaminated sites is based on variable protection goals, whereby total contents and in part mobile contents are considered. Due to interactions of pollutants in soil and bound residues, total contents do not reflect the actual risk. In contrast an investigation based on availability/bioavailability of contaminants would enable a harmonization of the protection-goal-based evaluation and a closer-to-reality risk assessment for the individual location.  相似文献   

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