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The significance of PCBs in the atmosphere of the southern hemisphere
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.
Show more [+] Less [-]Photodegradation of halobenzenes in water ice
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.
Show more [+] Less [-]The elaboration of the ‘Stockholm Convention’ on Persistent Organic Pollutants (POPs): A negotiation process fraught with obstacles and opportunities
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.
Show more [+] Less [-]Marine pollution in the United States
2001
Boesch, Donald F.
Book review on Integrated Weed and Soil Management by eds. J.L. Hatfield, D.D. Buhler & B.A. Steward (ISBN 1-57504-069-7; Ann Arbor press (1998) 400 pp.)
2001
Kropff, M.J.
Diffuse pollution IV | Diffuse pollution four | Diffuse pollution 4
2001
Yamada, K (Kiyoshi)
From the 86 oral and poster papers originally presented, 28 papers have been selected for these proceedings. They are in seven focus areas: urban issues; watershed analysis; agriculture and forestry; groundwater; modeling analysis and application; policy consideration; and application of geographic information systems.
Show more [+] Less [-]Agrochemical pollution of water resources
2001
Salama, Ramsis B. | Kookana, Rai S.
Papers on Malaysia -- Thailand -- Australia.
Show more [+] Less [-]Control of Water Pollution from Agriculture
2001
Hamdy, A. (Centre International de Hautes Etudes Agronomiques Méditerranéennes, Bari (Italy). Institut Agronomique Méditerranéen)
Water Quality Modelling
2001
El-Sayed, A. (Drainage Research Institute, Open Drainage Dept.)
Monitoring of Natural Hydrocarbon Release from Oilsands Deposits in a Canadian River Basin
2001
Headley, J. (National Water Research Centre, Cairo (Egypt)) | Tawfic, T. A.
Athabasca Oil Sands are found in the McMurray formation in the Athabasca River Basin in Northern Alberta, Canada. Monitoring studies conducted during 1998-1200, have indicated that there is a preponderance of oil sands-derived hydrocarbons, primarily PAHs, their C14 alkylated analogues, and biomarkers, in downstream sediment samples of the tributaries relative to the upstream samples. The relative composition of these hydrocarbons are diagnostic of a petrogenic source, and provides a fingerprint for characterization of biofilm samples, aquatic invertebrates, and sediments in northern rivers and tributaries. Results of GC-MS analyses of sediments, confirm that the tributaries passing through the Fort McMurray oil sands regions contain significant levels of naturally derived hydrocarbons (2-50 mg/g). Field activities in heavily impacted areas should therefore continue to emphasize the tributaries draining through oil sands deposits, as opposed to the main-stem of the Athabasca River where hydrocarbon levels are subject to dilution from high sedimentation rates.
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