The
pollution of the Wadden Sea derives mainly from external sources,
i.e. the major rivers Elbe, Weser, Ems and the IJssel, the North Sea
and the atmosphere. Although long-time downward trends are observed
for most hazardous substances, there are no significant differences
between the situation described in QSR 2004 and the present
situation described in QSR 2009. Cleaning-up the Wadden Sea
obviously is a slow process.
