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Environmental risks of chemicals and genetically modified organisms: A comparison 全文
2001
Steinhäuser, K. G. (Klaus Günter)
The principles of precaution and sustainability require more consideration in the assessment of environmental risks posed by chemicals and genetically modified organisms. Instead of applying risk reduction measures when there are serious indications for damage, full scientific certainty is often waited for before taking action. The precautionary principle particularly should be applied in those cases in which the extent and probability of damage are uncertain, e.g. in the case of persistent chemicals which are additionally bioaccumulative or highly mobile. Based on these principles, environmental action targets for risks associated with GMOs and chemicals can be developed. Risk management not only includes statutory measures but also instruments designed to influence behaviour indirectly are important to achieve the goals. Particularly for risks of GMOs which provoke fear, risk communication is important. Some rules to which attention should be paid in communication with the public are presented.
显示更多 [+] 显示较少 [-]BETR North America: A regionally segmented multimedia contaminant fate model for North America 全文
2001
Macleod, Matthew | Woodfine, David G. | Mackay, Donald | McKone, Tom | Bennett, Deborah | Maddalena, Randy
We present the Berkeley-Trent North American contaminant fate model (BETR North America), a regionally segmented multimedia contaminant fate model based on the fugacity concept. The model is built on a framework that links contaminant fate models of individual regions, and is generally applicable to large, spatially heterogeneous areas. The North American environment is modeled as 24 ecological regions, within each region contaminant fate is described using a 7 compartment multimedia fugacity model including a vertically segmented atmosphere, freshwater, freshwater sediment, soil, coastal water and vegetation compartments. Inter-regional transport of contaminants in the atmosphere, freshwater and coastal water is described using a database of hydrological and meteorological data compiled with Geographical Information Systems (GIS) techniques. Steady-state and dynamic solutions to the 168 mass balance equations that make up the linked model for North America are discussed, and an illustrative case study of toxaphene transport from the southern United States to the Great Lakes Basin is presented. Regionally segmented models such as BETR North America can provide a critical link between evaluative models of long-range transport potential and contaminant concentrations observed in remote regions. The continent-scale mass balance calculated by the model provides a sound basis for evaluating long-range transport potential of organic pollutants, and formulation of continent-scale management and regulatory strategies for chemicals.
显示更多 [+] 显示较少 [-]Photodegradation of halobenzenes in water ice 全文
2001
Klán, Petr | Del Favero, David | Ansorgová, Alena | Klánová, Jana | Holoubek, Ivan
Results from the photolysis ofo, p-dichlorobenzene, bromobenzene, andp-dibromobenzene in water ice are reported. All phototransformations appeared to be based on dehalogenation, coupling, and rearrangement reactions in ice cavities. No photosolvolysis products, i.e. products from intermolecular reactions between organic and water molecules, were found. Many of the products were very toxic substances of a high environmental risk, such as PCBs. The results support our model, in which secondary, very toxic, pollutants can be formed in ice, snow, and atmospheric ice particles from primary pollutants through the action of solar irradiation. The photoproducts may be released to the environment by ice melting and evaporation.
显示更多 [+] 显示较少 [-]The spatial scale of organic chemicals in multimedia fate modeling : Recent developments and significance for chemical assessment 全文
2001
Scheringer, Martin | Hungerbühler, Konrad | Matthies, Michael
In the last years, the spatial range (SR) or characteristic travel distance (CTD) of organic chemicals has found increasing scientific interest as an indicator of the long-range transport (LRT) potential and, in combination with persistence, as a kind of ‘hazard’ indicator on the exposure level. This development coincides with European debates about more effective and more preventive approaches to the chemicals assessment, and about an international, legally-binding instrument for the phase out of persistent organic pollutants (POPs). Persistence and LRT potential are important issues in these debates. Here, the development of the concept of assessing the spatial scale from early ideas in the 1970s and 1980s to recent studies in the field of multimedia fate and transport modeling is summarized. Different approaches to the modeling of environmental transport (advective and dispersive) and different methods for quantifying the SR or CTD are compared. Relationships between SR or CTD and different persistence measures are analyzed. Comparison of these relationships shows that conclusions for chemical assessment should be based on an evaluation of different persistence and spatial scale measures. The use of SR or CTD and persistence as hazard indicators in the chemicals assessment is illustrated.
显示更多 [+] 显示较少 [-]Environmental policies for agricultural pollution control 全文
2001
Shortle, J. S. (James S) | Abler, David Gerrard
This book provides a review and guide to environmental policy options for the control of agricultural pollution (particularly water pollution) and the economic, administrative and political merits of such policies. The principal focus is on the developed world, particularly North America and Europe. The book covers: the issues concerning agriculture and water quality; the voluntary and indirect approaches for reducing externalities and satisfying multiple objectives; the estimation of the benefits and costs of pollution control policies; the pollution control policies in the USA and EU; and the decomposition of the effects of trade on the environment. The book contains 7 chapters and a subject index.
显示更多 [+] 显示较少 [-]The significance of PCBs in the atmosphere of the southern hemisphere 全文
2001
Ockenden, Wendy A. | Lohmann, Rainer | Shears, John R. | Jones, K. C. (Kevin C.)
Air monitoring stations were set up at 2 sites in the southern hemisphere — Moody Brook, Falkland Islands (51° 25′ S, 57° 56′W) and Halley, Research Station, Antarctica (75° 35′ S, 26° 30′ W). PCBs were monitored at the stations throughout 1999. Highest concentrations were observed when temperatures were greater. In general, concentrations were greater at Moody Brook than at Halley, although the difference in concentrations between sites was less for more chlorinated congeners. Air concentrations at both sites were compared with samples collected nearby over-water. Over water air concentrations were found to be greater than over land air concentrations. Concentrations were also compared with literature data for air concentrations at a remote site in the Canadian Arctic. Atmospheric concentrations of tri-chlorinated biphenyls were found to be approximately double those reported for Ellesmere Island in the Canadian Arctic, whilst concentrations in samples from Antarctica were very similar to those found in the high Arctic. Most other PCBs were a factor of 2–4 greater in the Canadian Arctic.
显示更多 [+] 显示较少 [-]Development of continental scale multimedia contaminant fate models: Integrating GIS 全文
2001
Woodfine, David G. | Macleod, Matthew | Mackay, Donald | Brimacombe, Jennifer R.
The incentives and approaches for modelling chemical fate at a continental scale are discussed and reviewed. It is suggested that a multi-media model consisting of some 20–30 regions, each of which contains typically seven environmental compartments represents a reasonable compromise between the issues of the need for detailed resolution, avoidance of excessive data demands and inherent complexity and transparency. Strategies adopted in compiling the Berkley-Trent (BETR) model for North America are discussed and used to illustrate the issues of selecting appropriate number and nature of segments, treatment of air and water flows and the acquisition of environmental data. It is suggested that GIS software can play a valuable role in gathering and processing such data and in the display and interpretation of the results of the model assessment. The BETR model will be a useful tool for describing the nature of persistence and long-range transport of chemicals of concern in the North American environment.
显示更多 [+] 显示较少 [-]The elaboration of the ‘Stockholm Convention’ on Persistent Organic Pollutants (POPs): A negotiation process fraught with obstacles and opportunities 全文
2001
Karlaganis, Georg | Marioni, Renato | Sieber, Ivo | Weber, Andreas
The conclusion in December 2000 of the negotiations for the ‘Stockholm Convention’ can clearly be labeled as a success. The Convention text was negotiated in merely five sessions of the Intergovernmental Negotiating Committee (INC) and accomplished after its fifth session despite the fact that numerous controversial issues, such as the inclusion of new substances under the ambit of the Convention, the acknowledgement of the precautionary principle or — clearly most controversial the financing mechanisms, remained to be resolved. This paper attempts to provide a somewhat impressionistic account of the negotiations leading to the conclusion of the ‘Stockholm Convention’ as experienced by the members of the Swiss delegation participating in the negotiations of the INC. Besides a brief overview on the ‘history’ of the negotiations, it will focus on some issues of special interest — and controversy — to the negotiators, and finally attempt to provide an outlook on the future of the work performed by the INC and the implementation of the Convention. Issues of special interest are environmental policy issues, capacity building and financing, trade-related issues, precautionary principles, and technical and scientific issues.
显示更多 [+] 显示较少 [-]Marine pollution in the United States 全文
2001
Boesch, Donald F.
Agrochemical pollution of water resources
2001
Salama, Ramsis B. | Kookana, Rai S.
Papers on Malaysia -- Thailand -- Australia.
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