Waste water treatment plants

The sewage water is treated in waste water treatment plants (WWTP) before it is discharged to surface waters (rivers, lakes). A part of the surface water infiltrates to groundwater. Conventional WWTP technologies vary greatly in their ability to eliminate pharmaceutical residues from sewage water, implying that the WWTP effluent also contains pharmaceutical residues. The effective elimination is possible only when applying a rather costly tertiary treatment.

Another way how pharmaceutical residues from WWTP pollute surface water and groundwater is by spreading the WWTP stabilized sewage sludge as fertilizer on agricultural land, resulting in soil pollution and infiltration of pharmaceutical residues into groundwater (also absorption in plants, as part of the food chain).