Predominantly decreasing trends
Both the discharges in industrial waste water of oxygen-binding substances (BOD, COD), nutrients(nitrogen, phosphorous) and most heavy metals show a decreasing trend in the period 2000-2010. This decrease varies from 30 % for zinc to 72 % for chromium. Under the influence of policy measures (e.g. discharge standards, environmental charges on waste water), a considerable number of companies have also made substantial efforts to reduce their discharges. In 2010 the discharged waste loads for a number of substances were higher than in 2009, when the financial-economic crisis had a major effect. In 2010 there is once again increasing industrial activity (production index more than 7 % higher than in 2009).
The discharges of lead show an unstable trend. The large peak in 2010 is attributable to the discharges by a single company.
The chemical subsector has succeeded in significantly reducing the discharges of various pollutants during the last ten years (e.g. -63 % for copper, -59 % for nitrogen, -34 % for arsenic and -33 % for zinc) but still represents a major part of industrial discharges of nearly all substances. The foodstuff subsector is primarily responsible for the discharge of oxygen-binding substances and nutrients but has been able to reduce its discharges by one-third during the last ten years. The metal subsector is mainly relevant for the discharges of metals and has since 2000 been able to achieve substantial discharge reductions (-93 %, -77 %, -69 % and -67 % for cadmium, chromium, zinc and nickel respectively). The textiles subsector is responsible for a major part of the discharges of chromium but has been able to reduce them by more than 80 % in the last ten years.