Municipal waste water treatment. Discharges, treatment efficiencies and sludge disposal

5   Content of heavy metals in sewage sludge. The whole country. 2001. Milligrams per kilo dry weight
  Average content Maximum registered content Limit value for agricultural areas Limit value for parks etc. Change in average content 2000-2001
  Milligrams per kilo dry weight Per cent
Cadmium (CD) 1.0 5.9 2 5 0.0
Chromium (CR) 24.5  552.0  100  150 -0.3
Copper (CU)  227.0 2 200.0  650 1 000 -17.1
Mercury (HG) 0.8 41.0 3 5 -0.1
Nickel (NI) 12.7  912.0 50 80 -1.8
Lead (PB) 16.4  130.0 80  200 -4.2
Zinc (ZN)  302.8 1 720.0  800 1 500 -14.6

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