Die Mathematik im Kreise der Naturwissenschaften II

The Science of Nature -     

The effect of export to the deep sea on the long-range transport potential of persistent organic pollutants

Background

Export to the deep sea has been found to be a relevant pathway for highly hydrophobic chemicals. The objective of this study is to investigate the influence of this process on the potential for long-range transport (LRT) of such chemicals.

Methods

The spatial range as a measure of potential for LRT is calculated for seven PCB congeners with the multimedia fate and transport model ChemRange. Spatial ranges for cases with and without deep sea export are compared.

Results and Discussion

Export to the deep sea leads to increased transfer from the air to the surface ocean and, thereby, to lower spatial ranges for PCB congeners whose net deposition rate constant is similar to or greater than the atmospheric degradation rate constant. This is fulfilled for the PCB congeners 101, 153, 180, and 194. The spatial ranges of the congeners 8, 28, and 52, in contrast, are not affected by deep sea export. With export to the deep sea included in the model, the spatial ranges of the heavier congener are similar to those of the lighter ones, while the intermediate congeners 101 and 153 have the highest potential for long-range transport.

Conclusions

Transfer to the deep ocean affects the mass balance and the potential for LRT of highly hydrophobic chemicals and should be included in multimedia fate models containing a compartment for ocean water.     

Diffusion von Wasser und Wasserdampf durch die menschliche Haut

The Science of Nature -     

Lessons learned for a more efficient knowledge and technology transfer to South American countries in the fields of solid waste and contaminated sites management.

The present paper describes the development, performance and conclusions derived from three know-how and technology transfer projects to South American countries. The first project comprised a collaborative study by European and South American universities to find sustainable solutions for Chilean and Ecuadorian leather tanneries which had underachieving process performances. The second project consisted of investigations carried out in a Brazilian municipality to enhance its municipal solid waste management system. The final collaborative programme dealt with the initial identification, evaluation and registration of suspected contaminated sites in an industrial region of Chile. The detailed objectives, methods and procedures applied as well as the results and conclusions obtained in each of the three mentioned projects are presented, giving special attention to the organizational aspects and to the practical approach of each programme, concluding with their main advantages and disadvantages for identifying a set of qualitative and quantitative suggestions, and to establish transferable methods for future applications.